WO2009045023A2

WO2009045023A2 - Compositions of increasing microbial populations on surfaces and their uses

Info

Publication number: WO2009045023A2
Application number: PCT/KR2008/005701
Authority: WO
Inventors: Dal Soo Kim
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-10-05
Filing date: 2008-09-26
Publication date: 2009-04-09
Anticipated expiration: 2010-04-05
Also published as: JP2010540622A; EP2207878A2; US20100234224A1; WO2009045023A3; CN101883849A; KR20090035162A; KR100954297B1; EP2207878A4

Abstract

The present invention relates to compositions that can improve biological activity or can increase population density of natural or beneficial microorganisms on surfaces. By proper use of the compositions, the present invention provides uses of protecting plants from plant pathogen, harmful insects or weedy plants or of promoting plant growth. By proper use of the compositions in the present invention, biological activity or population density of natural or beneficial microorganisms can be increased and the improved biological activity or population density of the microorganisms can protect plants from harmful organisms including plant pathogens, harmful insects or weedy plants or can promote plant growth.

Description

COMPOSITIONS OF INCREASING MICROBIAL POPULATIONS ON SURFACES AND THEIR USES

TECHNICAL FIELD The present invention relates to compositions to increase biological activity or po pulation density of microorganisms on surface. Compositions of the present invention c an be used to protect plants from harmful organisms such as plant pathogens, insects o r weedy plants, or to promote plant growth.

BACKGROUND ART

There are various natural microorganisms living on plant surfaces including leaf, stem, branch, flower or fruit, on soil surface of lawn, or surfaces of an animal such as c ockroaches, snails or ants (hereafter referred as "surfaces"). These microorganisms exi st together with saprophytic, symbiotic or parasitic interactions. On plant surfaces, para sitic plant pathogens cause plant diseases usually by increasing their populations under favorable environmental conditions, and harmful insects also increase their population s resulting in damages to plants. Weed plants also results in reduced growth of cultivati ng crops or plants due to competition among plants for nutrition or space. The plant pat hogens, harmful insects and weeds (hereafter referred as "harmful organisms") have be en threats of human efforts to secure stable production of foods for mankind. Currently, humans mainly rely on use of chemical pesticides to protect plants from these harmful organisms. Up to now, chemical pesticides have been used as the most effective mean s for protecting crops from plant pathogens, insects and weeds. Current market size is approximately 30 US billion dollars in the world and 1 US billion dollars in Korea. Howev er, chemical pesticides are known with many adverse problems of causing ecological di sorders by suppressing not only harmful organisms but also other natural beneficial org anisms as an adverse side effect. Residues or metabolites of chemical pesticides may also have a toxic effect to producers of chemical pesticides, farmers or consumers. In a ddition, repeated use of chemical pesticides may induce resistance to plant pathogens, insects or weeds, resulting in their reduced sensitivity to chemical pesticides. Sometime s, leakage of chemical pesticides may cause air, water or soil contamination of our envi i ronment.

Human efforts have been keeping to supplement or to replace chemical pesticid es that have potential risks as described above. One alternative is use of certain microo rganisms to manage harmful organisms. These microorganisms (hereafter referred as " plant protection microorganisms") have their biological activity to inhibit certain harmful organisms under favorable environment conditions for their growth. This microbial meth od has been socially needed mainly due to its safety profile to mammals and environme nts in comparison to chemical pesticides. Recently, many countries including the United

States, European countries, Japan and Korea have launched regulations to encourage research, development and registration of industrial products of "plant protection micro organisms" to manage "harmful organisms". "Plant protection microorganisms" are deve loped usually by being isolated from nature, artificially cultivated in their own media and formulated before use. However, this microbial method also has technical limitations an d has not been successful in industrial viewpoints compared to chemical pesticides due to the technical limitations, although it is known to be safe to humans and environment . The microbial method is usually not sufficient to protect plants from "harmful organism s" or highly variable in its efficacy that highly depends on environmental conditions. Ano ther limitation is relatively higher cost of microbial products, compared to chemical pesti cides. "Plant protection microorganisms" usually require stricter conditions for their survi val or biological activity during manufacturing, transportation, storage or after applicatio n by farmers in fields, and requirement of these strict conditions often results in higher c osts than chemical pesticides. Especially, unstable or unreliable efficacy depending on environmental conditions often requires growers of taking economic risks from damage s by "harmful organisms". These problems are considered main reasons why microbial method has not been adopted widely in industry, although it is generally known to be sa fe to humans and environment.

People have been using chemical fertilizers for long time to enhance agricultural productivity. However, repeated use of chemical fertilizers has caused reduced producti vity of agricultural land by salt accumulation in soils and other negative problems such a s water pollution. In order to overcome these problems, people have been trying to reco ver productivity of agricultural land by using natural organic materials instead of chemic al fertilizers. Natural organic materials are known to exhibit fertilizer effect by their meta bolites including small organic molecules and minerals. These organic materials are ma inly degraded by natural microorganisms. These microorganisms (hereafter referred as "plant growth promotion microorganisms") exist in nature in a great amount, and proper use of these microorganisms can replace or supplement chemical fertilizers. However, " plant growth promotion microorganisms" have similar technical limitations as in the micr obial method with "plant protection microorganisms" such as lower efficacy, unstable or unreliable efficacy by being sensitive to environment conditions, higher price than chemi cal fertilizers. These technical limitations also lead to limited use of microbial method in industrial applications.

The above-described unstable or insufficient effect of the methods based on "pla nt protection microorganisms" and "plant growth promotion microorganisms" (hereafter r eferred as "beneficial microorganism") is caused by the fact that biological activities of p lant protection or growth promotion on plant surfaces often largely depends on environ mental conditions for their survival. More specifically, biological activities of microorgani sms on plant surface are known to be affected by factors such as moisture, temperatur e, UV light, nutrients and so on (Steven E. Lindow and Maria T. Brandl. 2003. Microbiol ogy of the phyllosphere. Applied and Environmental Microbiology 69:1875-1883). Benef icial microorganisms applied to plant surface for plant protection or plant growth promoti on are also generally affected for their survival or biological activities by these environm ental factors. Especially, under environment conditions that cause dryness of plant leaf and then reduced availability of nutrients in leaf or that expose plant leaves direct to sun light, population of these beneficial organisms significantly decreases or their biologica I activities are lowered.

The present invention was focused on developing compositions for strengthenin g availability of water and microbial nutrients on plant surfaces, and therefore resulting i n increased population or biological activities of microorganisms on surfaces. Water on plant surfaces is provided by natural precipitation or artificial irrigation, and water amou nt is fluctuating on plant surfaces in terms of time and space. Generally microorganisms are more sensitive to water for their biological activities than plants. More specifically, water on plant surface is dropped off leaves down to ground surface by gravity or vanis hed from plant surfaces by evaporation. And water remaining on plant surfaces is also v ariably distributed by surface structures on leaves. For example, water remaining on pla nt surfaces is mainly found along leaf veins or around trichomes, and results in uneven distribution of water that leads limited availability of water to microorganisms living on Ie aves. This may be one of reasons why microorganisms are found along leaf veins or ar ound trichomes. Limited water availability for microorganisms (hereafter referred as "av ailable water") on plant surfaces generally leads to reduced microbial population or redu ced biological activity and transformation into resting structures like spores. Therefore, " available water" is considered highly important to increase or maintain microbial populat ions or their biological activities. Furthermore, "available water" is also important for avai lability of microbial nutrients on surfaces to be accessible to microorganisms on plant su rfaces. Microorganisms usually do not have means for active movement on plant surfac es and thus tend to get moved passively by water stream existing on plant surfaces. Th erefore, limited water availability also means limited availability of microbial nutrients tha t are dissolved or suspended in water. As such, "available water" also plays a role to del iver microbial nutrients to microorganisms on plant surfaces.

Among microbial nutrients, carbon and nitrogen sources are utmost important for microorganisms to maintain their population or to express their biological activities. Ge nerally, within a certain space and time point, various natural microorganisms exist on p lant surface in a great amount. This coexistence of various microorganisms results in hi gh competition among microorganisms for microbial nutrients (Steven E. Lindow and M aria T. Brandl. 2003. Microbiology of the phyllosphere. Applied and Environmental Micr obiology. VoI 69:1875-1883). Especially, "beneficial microorganisms" that are introduce d artificially by human for plant protection or plant growth promotion are usually position ed unfavorable for their survival or biological activities on plant surfaces that are already occupied by natural microorganisms with superior ecological fitness. Most "beneficial microorganisms" are grown artificially in culture media to optimize their maximum growt h in population and then introduced to natural field conditions. Because of this reason, t hese "beneficial microorganisms" cannot be considered positioned competitive in natur al ecological conditions. In addition, these "beneficial microorganisms" are generally ma nufactured in their resting structures like spores that are biologically less active than the ir vegetative structures. These manufacturing processes of growing them in artificial cult ure media and storing in resting structures can be the reasons of low competitiveness o f "beneficial microorganisms" on plant surfaces compared to natural microorganism that are ecologically already fit for their survival.

Natural microorganisms that live on plant surfaces compete with plant pathogeni c microorganisms for water, microbial nutrients or space, and this competition may resul t in reduced plant disease development. Therefore, increased competition between nat ural saprophytic microorganisms and plant pathogenic microorganisms can be consider ed desirable in terms of plant protection from plant pathogens. Moreover, in order to pro tect certain plants from certain plant pathogens, use of certain microorganisms that are selected for the competition, artificially cultured on media and to have increased populat ion can be more desirable than simple increase of natural saprophytic microorganisms. On the other hand, plant protections from harmful insects or weedy plants by using natu ral microorganisms are fairly difficult because their population density or biological activi ty is not high enough to inhibit harmful insects or to suppress weedy plants. In this case , beneficial microorganisms that are artificially grown in culture media are more desirabl e. Therefore, certain beneficial microorganisms that specifically inhibit certain harmful in sects or specifically inhibit certain weeds are needed to be artificially introduced to plant surfaces. For promotion of plant growth by using beneficial microorganisms, artificial in troduction is desirable than use of natural saprophytes.

It has not been technically well established to provide microbial nutrients that can be used selectively by beneficial microorganisms but not by natural microorganism po pulation. In nature, microorganisms on plant surfaces keep dynamically changing their s pedes and numbers in given times and spaces. On plant surfaces, it is known that man y different microorganisms exist together simultaneously. For example, 37 genera and 8 5 species of microorganisms are reported in phyllosphere of oat, olive, sugarcane and wheat (Ching-Hong Yang, David E. Crowley, James Borneman and Noel T. Keen. 2001 . Microbial phyllosphere populations are more complex than previously realized. PNAS. Vol. 98:3889-3894). Such diversity of microorganisms may be similarly applied to other plants. Therefore, when beneficial microorganisms are artificially introduced on plant su rfaces, they have to compete with other natural microorganisms within the same space under various environmental conditions. This dynamic competition makes beneficial mic roorganisms difficult to occupy a dominant position in given spaces for long time. One method to overcome this limitation can be use of microbial nutrients that are selectively used by certain beneficial microorganisms. For example, certain beneficial microorganis ms can use oils as their carbon sources, whereas most natural microorganisms cannot use oils as nutrients. Another method is use of antimicrobial agents that are not inhibitor y to one or some of beneficial microorganisms but inhibitory to most natural microorgani sms. With this method, beneficial microorganisms can establish their population securel y in their early application stage while natural microorganisms are selectively controlled. If needed, beneficial microorganisms can be induced to be resistant to certain antimicr obial agents in the laboratory and may be used for this purpose. Some chemical bacteri cides or fungicides can be used as the antimicrobial agents. However, even in this case , these antimicrobial agents are used at much lower application rates, due to the differe nt purpose of their use and low use concentration.

A key concept of the present invention is to use super absorbent polymer (hereaf ter referred as "SAP") to increase population density or biological activity of microorgani sms on plant surfaces. SAP in the present invention is defined as all polymers that have hydrophilic function and that can hold tap water at least for several ten times of their o wn weight for a certain period of time. SAP was introduced by USDA in 1970s and indu strially used since 1980s. Their main applications are for sanitation purposes including disposable diapers and hygienic bands for women. In agriculture and forestry, SAP also has been used in soil to provide plant roots with water for longer time in arid area or to increase aeration in soil (Sang-Bum Park. 1994. Characteristics of Super Absorbent Pol ymer and State of the Art. Mokchae Konghak 22(1 ): 91-112). Although SAP can be clas sified into natural and synthetic SAP based on source of its raw skeleton materials, it w as obtained by crosslinking soluble raw polymer materials into non-soluble forms, which consequently can hold water several ten times of water of its own weight in a gel form. (Sang-Bum Park. 1994. Characteristics of Super Absorbent Polymer and State of the Ar t. Mokchae Konghak 22(1 ):91 -112).

USP No. 9,009,020 describes manufacturing process of SAP for agricultural appl ication. It is disclosed in this patent that SAP can be used in soil, on seed or root to impr ove aeration in soil, to improve germination and emergence of seeds, to improve plant growth and yield, and to reduce cost of water irrigation. For this purpose, inventors desc ribe convenient use by manufacturing SAP having the size in range of 5-24 meshes. Ko rean Patent Application Laid-Open No. 2002-0002852 describes use of SAP on seeds pelleted with ectomycorrhizae to increase storage period, help germinated root to come out of epidermis of pelleted seeds and to reduce water stress of plant seedlings. Anoth er research was conducted in Korea using 2% SAP of soil by weight in potting soil to im prove suppression activity of Serratia plymutica A21-4 that is effective against soil born plant disease. By this application, emergence and growth promotion of red-pepper seed lings were reported to be significantly enhanced (Shun-Shan Shen, Won-il Kim and Cha ng-Seuk Park. 2006). Effect of hydrogel on survival of Serratia plymuthica A21-4 in soils and plant disease suppression. Plant Pathology Journal Vol. 22:364-368). In addition, population density of Serratia plymutica A21-4 was reported to be significantly increase d on roots and rhizosphere whereas population density of Phytophthora capsici, a caus al pathogen of red-pepper blight, was reduced.

However, all of these reports are directed to the use of SAP in soil that is worki ng under soil surface. There has been no report about the use of SAP that is applied o n plant surfaces to increase population density or biological activities of natural or ben eficial microorganisms. In addition, there has been no report of using SAP to protect pi ants from harmful microorganisms or to promote plant growth by increasing population density or biological activities of microorganisms on plant surfaces.

DETAILED DESCRIPTION OF THE INVENTION Technical Problem

The present invention was based on an idea of protecting plants from harmful or ganisms or promoting plant growth by increasing population densities or biological activi ty of saprophytic or beneficial microorganisms on plant, soil and organism surfaces, in c ombination with SAP to increase water availability needed for microorganisms on surfac es. Therefore, the present invention provides compositions containing SAP (hereafter r eferred as "SAP composition") which can be used for increasing population densities or biological activity of microorganisms on surface, and can be used to protect plants from harmful organisms, to promote plant growth or others.

Technical Solution

The present invention provides SAP compositions to increase microbial populati on or biological activities on plant surfaces. Also the present invention describes applica tions of SAP compositions on plant surfaces including leaves, stems, branches, flowers and fruits, soil surface where grasses grow, or animal surfaces of snails, cockroaches o r ants. Using SAP compositions, the present invention describes how effectively SAP co mpositions can protect plants from harmful organisms or promote plant growth.

Advantageous Effects

SAP compositions of the present invention may provide additional water or micro bial nutrients needed for natural or beneficial microorganisms living on surfaces of plant s, soil and animals. This additional water or microbial nutrients may increase microbial p opulation on surfaces and improve biological activity of the microorganisms. More speci fically, the SAP compositions of the present invention provide additional water or microb ial nutrients that extend supplying time of water or microbial nutrients to increase microb ial population on surfaces. SAP compositions added with microbial nutrients are more e ffective to increase microbial populations on surfaces. The SAP compositions of the pre sent invention, which comprise SAP, microbial nutrients and specific beneficial microorg anisms, are prepared to increase the population of artificially-introduced beneficial micr oorganisms rather than natural saprophytic beneficial microorganisms. When the SAP c ompositions comprise beneficial microorganisms that are inhibitory to growth of natural saprophytic microorganisms, these SAP compositions may inhibit natural microorganis ms, thus resulting in reduction of population density of the natural microorganisms. In a ddition, by adding some specific beneficial microorganisms that are selectively growing on specific microbial nutrients or that are resistant to certain specific antimicrobial agent s in the SAP compositions, the SAP composition of the present invention can be used t o increase specific beneficial microorganisms rather than natural saprophytic beneficial microorganisms. In summary, the SAP compositions of the present invention provide may be used to increase natural saprophytic or added beneficial microorganisms, to reduce populati on density of natural microorganisms by inhibitory activity of secondary metabolites pro duced by added beneficial microorganisms or by antimicrobial agents that are selectivel y added in the SAP compositions. Natural saprophytic or added beneficial microorganis ms that are increased in population by using the SAP composition of the present inventi on may compete more effectively with plant pathogenic microorganisms for microbial nu trients and spaces that result in reduced disease development. When the SAP composi tions added with certain microorganisms that have insecticidal activity, the insecticidal microorganisms may have higher chance of suppressing harmful insects on surfaces w hen applied properly to plant surfaces. When the SAP compositions added with herbici dal microorganisms, the herbicidal microorganisms may have higher chances of suppre ssing weedy plants in selective ways when applied properly to surfaces of weedy plants . When the SAP compositions added with specific beneficial microorganisms that are in hibitory to growth of snails, cockroaches or ants, the beneficial microorganisms may als o have higher chances of suppressing or eliminating harmful animals when applied pro perly to animal surfaces.

BEST MODE FOR CARRYING OUT THE INVENTION

To achieve the above-described purpose of the invention, the present invention provides compositions comprising SAP to increase microbial population or biological act ivities of beneficial microorganisms on plant, soil or animal surfaces of plant, soil and an imal.

The SAP composition of the present invention additionally may contain at least o ne nutrient that can be used by natural saprophytic or added beneficial microorganisms.

The SAP composition of the present invention additionally may contain at least o ne beneficial microorganism that can inhibit plant pathogens, harmful insects or weedy plants or that can promote plant growth.

The SAP composition of the present invention additionally may contain at least o ne beneficial microorganism that can inhibit harmful animals.

The SAP composition of the present invention additionally may contain at least o ne surfactant to achieve even spreading of the composition on surfaces.

The SAP composition of the present invention additionally may contain at least o ne single or multiple mineral salt to improve wettability of the composition in water.

The SAP composition of the present invention is characterized in that SAP is star ch-based SAP. The SAP composition of the present invention is characterized in that the SAP c ontent ranges from 20% to 95% by weight.

The SAP composition of the present invention is characterized in that the SAP c ontent ranges from 0.02% to 1.0% by weight in a given water volume, when the compos ition is diluted with water.

The SAP composition of the present invention is characterized in that the surface s are surfaces of plant leaves, stems, branches, flowers or fruits, surfaces of ground soi I, or surfaces of animals.

The SAP composition of the present invention is characterized in that the microbi al nutrient is PLNT powder of culture broth that consists of potato dextrose broth, Luria broth base, nutrient broth and tryptic soy broth each comprised in an equal amount by weight.

The SAP composition of the present invention is characterized in that the plants are selected from cucumber, red pepper, potato, rice, tomato, barley, wheat, pear or ros e.

The SAP composition of the present invention is characterized in that the benefic ial microorganisms are selected from bacterial genera of Bacillus, Paenibacillus or Stre ptomyces, fungal genera of Trichoderma, Ampelomyces or Acremonium.

The SAP composition of the present invention is characterized in that the plant p athogens are selected from Magnaporthe ghsea, Thanatephorus cucumeris, Phytophth ora capsici, Botrytis cinerea, Puccinia graminis, Blumeria graminis = Erysiphe graminis or Sphaerotheca fusca.

The SAP composition of the present invention is characterized in that the harmfu I insect is genus Plutella.

The SAP composition of the present invention is characterized in that the weedy plants are the plants that are growing in field in a given time and space that are not inte nded by plant growers. The SAP composition of the present invention is characterized in that the harmfu I animals are cockroaches, ants or snails.

The present invention provides use of the SAP compositions on plant surfaces or soil surfaces.

The present invention provides use of the SAP compositions to suppress harmful organisms on surfaces or to promote plant growth.

Hereafter, more specific descriptions of the present invention are given.

The present invention is about compositions of increasing biological activities or population density of natural saprophytic or added beneficial microorganisms on surfac es and their uses. The compositions of the present invention comprise SAP that is supe r absorbent polymer of water. Depending on application and necessity, the composition s of the present invention may contain microbial nutrients or beneficial microorganisms.

Furthermore, wetting agents or surfactants may be added to improve wettability in wa ter and spreadability on surfaces, respectively. In the present invention, a key material u sed to increase water amount and to extend supply time of water available for microorg anisms are super absorbent polymer (hereafter referred as "SAP"). Microbial nutrients were composed of culture broth that is widely used by microbiologists in laboratory for research. Beneficial microorganisms were obtained from a commercial provider or obt ained from researchers who study the corresponding microorganisms. In the compositio ns of the present invention, mineral salts and surfactants are selected and properly use d to improve wettability in water, and spreadability of the composition on surfaces, resp ectively.

1. SAP (super absorbent polymer)

The SAP used mainly in the present invention is starch-based, specifically Zeba ( product brand name), comprising a major component starch-g-poly(2-propenamide-co- 2-propenoic acid) potassium salt (CAS Registry No. 107830-79-5) that is manufactured by Absorbent Technologies, Inc. The SAP content was 50% of the compositions by wei ght prior to dilution in water, and 0.02%-1.0% by weight in a given water volume when d iluted in water. The SAP content in said SAP compositions and examples, the SAP cont ent was 0.5% by weight in a given water volume. For comparison purpose, an acrylamid e-based SAP (GS-3000), manufactured by Kolon Industries Inc., was used instead of Z eba, which resulted in similar effects of increasing microbial population when tested on cucumber leaves. In the present invention, SAP was milled into fine powders to have a diameter the same or less than 0.1 mm. Smaller the SAP particles, better the SAP susp ension after dilution spreads over wide range of plant surfaces. However, the above-de scribed kinds, contents and diameters of SAP were given to exemplify the present inve ntion and does not restrict kinds and a method of preparing SAP that are comprised in compositions of the present invention.

2. Microbial nutrients

In the present invention, a microbial nutrient, named as PLNT powder medium, was used. The PLNT powder medium consists of potato dextrose broth, Luria broth bas e, nutrient broth and tryptic soy broth that are all manufactured by Difco Laboratories, U SA. One quarter of recommended use of each medium was combined to prepare the P LNT powder medium. Good growth of various microorganisms was confirmed on PLNT agar medium. The PLNT powder medium was used with 5% by weight in the compositi on of the present invention. However, the PLNT powder broth was used as an example of the present invention and kinds or contents of microbial nutrients are not limited ther eto. Rather, other microbial nutrients that provide carbon, nitrogen, amino acids, mine rals or vitamins required for microbial growth can be also used.

3. Beneficial microorganisms

All beneficial microorganisms used in the present invention were obtained from a commercial provider or from researchers. Beneficial microorganisms used for plant pro tection from plant pathogens belong to bacterial genera of Bacillus, Paenibacillus or Str eptomyces or fungal genera of Trichoderma, Ampelomyces or Acremonium. Beneficial microorganism used for plant protection from harmful insect belongs to bacterial genus of Bacillus thuringiensis, and that used for plant protection from weedy plant belongs t o bacterial genus of Botrytis cinerea. Beneficial microorganism used for growth promoti on of plants belongs to bacterial genus of Bacillus vallismortis. References of each ben eficial microorganism are given below.

<Reference for beneficial microorganisms > 1. Beneficial microorganisms used for plant protection from plant pathogens

(1 ) Paenibacillus elgii (SD17)

A. Kim, D. S., Bae, C. Y., Jeon, J. J., Chun, S. J., Oh, H. W., Hong, S. G., Baek, K. S., Moon, E. Y., and Bae, K. S. 2004. Paenibacillus elgii sp. nov., a novel species with broa d antimicrobial activity. International Journal of Systemic and Evolutionary Microbiology 54:2031-2035.

B. Kim, D. S., Bae, C. Y., Kim, D. H, Chun, S. J., Choi, S. W., and Choi, K. H. 2005. Pa enibacillus elgii SD17 as a biocontrol agent against soil-borne turf diseases. Plant Path ology Journal 21 :328-333.

C. Korean Patent No. 0457025

(2) Bacillus subtilis (QST713)

A. USP No. 6060051

(3) Bacillus subtilis (GB-0365)

A. Korean Patent No. 294023

(4) Streptomyces sp. (A020645)

A. Lee, H. B., Cho, J. W., Park, D. J., Li, C. T., Ko, Y. H., Song, J. H., Koh, J. S., Kim, B . J. Kim, C. J. 2004. In vivo screening for biocontrol agents (BCAs) against Streptomyce s scabiei causing potato common scab. Plant Pathology Journal 20: 110-114.

B. Korean Patent No. 0563298

(5) Trichoderma harzianum (YC459) A. Lee, S. K., Sohn, H. B., Kim, G. G. and Chung, Y. R. 2006. Enhancement of biologic al control of Botrytis cinerea on cucumber by foliar sprays and bed potting mixes of Trie hoderma harzianum YC459 and its application on tomato in the greenhouse. Plant Path ology Journal 22:283-288.

B. Korean Patent No. 0417632

(6) Ampelomyces quisqualis (AQ94013)

B. Korean Patent No. 0332480

(7) Acremonium strictum (BCP)

A. Kim, J. C₁ Choi, G. J., Kim, H. J., Kim, H. T., Ahn, J. W. and Cho, K. Y. 2002. Verla melin, an antifungal compound produced by a mycoparasite, Acremonium strictum. PIa nt Pathology Journal 18:102-105.

B. Korean Patent No. 0299768

2. Beneficial microorganisms used for plant protection from harmful insects

(8) Bacillus thuringiensis subsp. aizawai (NT0423)

A. Korean Patent No. 0280380

3. Beneficial microorganisms used for plant growth promotion

(9) Bacillus vallismortis (EXTN-1) A. Park, K. S., Paul, D. and Yeh, W. H. 2006a. Bacillus vallismortis EXTN-1- mediated growth promotion and disease suppression in rice (Oryza sativa L). Plant Pathology Jo urnal 22:278-282.

B. Park, K. S., Paul, D., Ryu, K. R., Kim, E. Y, and Kim, Y. K. 2006b. Bacillus vallismorti s strain EXTN-1 mediated systemic resistance against Potato Virus X and Y (PVX & PV

Y) in the field. Plant Pathology Journal 22:360-363.

C. Park, K. S., Paul, D., Kim, Y. K., Nam, K. W., Lee, Y. K., Choi, H. W. and Sang Y. L. 2007. Induced systemic resistance by Bacillus vallismortis EXTN-1 suppressed bacteria I wilt in tomato caused by Ralstonia solanacearum. Plant Pathology Journal 23:22-25.

D. Korean Patent No. 0379022

In the present invention, for experimental purpose, microorganisms obtained from one Ii ter of water shaken vigorously in a 250 ml of Erlenmeyer flask with 100 g of fresh cucu mber leaves sampled from adult cucumber plants, left statically for 30 minutes, shaken vigorously again, and then filtered through two layers of sterile cheese cloths (hereafter referred as "leaf wash water") were used as natural microorganisms. In the present inve ntion, plant pathogens were artificially cultured. For plant pathogens that are not cultura ble due to their intrinsic obligate parasitism, inoculum was obtained from plants which a re infected with the pathogen and show typical symptom of the infection. In the present i nvention, larva of Plutella species was used as a harmful insect. In principle, most bac teria or fungi listed on "The manual of biocontrol agent" published by BCPC in 2004 can be considered as beneficial microorganisms. In the manual, beneficial microorganisms that are established on plant surface or soil surface in advance to arrival of plant patho gens compete with plant pathogens for nutrition or space that results in plant protection. In case of plant protection from harmful insects, beneficial microorganisms are taken i nto inside harmful insects and results in death or inactivation of harmful insects. In case of plant protection from weedy plants, beneficial microorganisms cause diseases that are pathogenic specifically only to the weedy plants. Therefore, the experiments in the present invention are only to illustrate the present invention and do not limit kinds of be neficial microorganisms or harmful organisms.

4. Preparation of microbial compositions Microbial compositions in the present invention was prepared by milling and mixing of e ach component as powder with particle size that is the same or less than 0.1 mm in ave rage. Among the components of the present invention, SAP was the starch-based SA P. Microbial nutrient was the PLNT. Beneficial microorganisms were obtained from a c ommercial provider or obtained, isolated for pure culture in laboratory, cultured and pre pared as powder by a freeze-drying technique. In addition, 5% of surfactant in powder was used to accomplish even spreading of the composition on plant surface. In the pre sent invention, the surfactant was softanol (CAS Registry No. 68131-40-8) manufacture d by lneos Oxide Ltd., UK. Sofanol was adsorbed to white carbon supplied by Jungwoo Chemical, Korea, with 1 :1 ratio by weight. More specifically, softanol is a non-ionic sur factant obtained by adding ethylene oxide to linear secondary alcohol with 12-14 alkyl c arbons. Complex mineral salts were used in the microbial composition to improve wetta bility of the composition in water. Mirigun powder, manufactured by Daeyoo, Korea, was added as a wetting agent with 30% ratio by weight to microbial compositions. Mirigun i s a fertilizer to provide minerals required for plant growth. In the present invention, Mirig un was used as carrier and to improve wettability in water based on its high solubility in water and high specific gravity. A single mineral salt such as calcium chloride can be al so applied to microbial compositions in the present invention. For compositions without containing beneficial microorganisms, Mirigun powder was used with 40% ratio by weig ht. Content of each component in 100 g composition was described in Table 1.

Table 1.

Composition

^A) Population density of microorganism was expressed as logarithmic value of the colon y forming unit per gram powder (i.e., log cfu).

^B) Surfactant: Powder of softanol adsorbed to white carbon with 1 :1 ratio by weight.

^C) Carrier: Mirigun powder These compositions are only examples and do not limit kinds of SAP, beneficial microor ganisms, microbial nutrients, surfactants or carriers that can be used for the compositio ns of the present invention.

The present invention will now be described in greater detail with reference to th e following examples. However, it is only to specifically exemplify the present inventio n and in no case the scope of the present invention is limited by these examples.

Example 1 : Dynamics of microbial populations

In this Example, effect of each composition on population density of natural or ad ded beneficial microorganisms present on plant surface was monitored with time. For e xperimental purpose, natural microorganisms were defined as microorganisms obtained from one liter of water shaken vigorously in a 250 ml of Erlenmeyer flask with 100 g of fresh cucumber leaves sampled from adult cucumber plants, maintained undisturbed fo r 30 minutes, shaken vigorously again, and then filtered through two layers of sterile ch eese cloths (hereafter referred as "leaf wash water"). When cultured on LB agar mediu m, approximately 2x10⁵cfu/ml (=5.3 log cfu/ml) of natural microorganisms were detecte d. Of these, bacteria were present in a dominant amount of 90% of the total population. Each composition from the present invention at 0.5% by weight was added to the leaf w ash water to become 10 ml in total volume. Seven discs of cucumber leaf in 3 cm diam eter were soaked for 30 min and placed on a Petri dish at room temperature. In addition

, for comparison purpose, each beneficial microorganism was added to 10 ml of the leaf wash water at the same rate and prepared as above. Composition without microbial n utrient or beneficial microorganism was also prepared for comparison purpose. Each pr eparation was incubated for 0, 1 , 2, 3, 5 and 7 day after treatment on LB agar media at room temperature. Microbial population was properly counted 3-7 days after incubation by dilution plating method. Beneficial microorganisms were differentiated by their uniqu e colony form on the media, and all the others were considered as natural microorganis ms. These results are summarized in Table 2.

Table 2.

Population dynamics of beneficial or natural microorganisms on discs of cucumber leaf

^A) Mcirobial population density was counted on basis of colony forming unit and transfor med into logarithmic number.

^B) NM = Natural microorganisms

^C) BM = Beneficial microorganisms that were artificially added to the leaf wash water

^D) WLR = Leaf wash water

As shown in Table 2, most of the beneficial or natural microorganisms were incr eased in their population when properly used with the compositions of the present inven tion. Population density of natural microorganism was increased up to 100-fold at certai n time point for some compositions. However, in case with composition 3 containing be neficial microorganism 1 and composition 4 containing beneficial microorganism 2, the density of the natural microorganisms was decreased or their increase rate was reduce d. This observation may be explained by antibiosis of the beneficial microorganisms 3 a nd 4 that have antimicrobial activity by producing secondary metabolites. For example, Paenibacillus elgii SD17 was reported with its broad antimicrobial activity (Kim, D. S., B ae, C. Y., Kim, D. H, Chun, S. J., Choi, S. W., and Choi, K. H. 2005. Paenibacillus elgii SD17 as a biocontrol agent against soil-borne turf diseases. Plant Pathology Journal 21 :328-333). Based on results in Table 1 , it was found that compositions of the present in vention provides more water and microbial nutrients to microbial population on cucumb er leaf and results in increased population density of natural or beneficial microorganis ms. In addition, in case with beneficial microorganisms with antimicrobial activity, the be neficial microorganisms were well established by decreased population density of natur al microorganisms or by reduced increase of population density of natural microorganis ms in accordance with the application of the composition of the present invention.

Example 2: Plant protection activity of compositions on plant seedlings from pla nt pathogens In this Example, compositions of the present invention were tested in growth cha mber for their plant protection activity against plant pathogens; Magnaporthe grisea, Th anatephorus cucumeris, Phytophthora capsici, Botrytis cinerea, Puccinia graminis and Blumeria graminis (i.e., Erysiphe graminis). The experiments were conducted on basis of general screening methods of chemical fungicides (Choi, G. J, Kim, J. -C₁ Lee, S. - W., Jang, K. S., Kim, J. -S., and Cho, K. Y. 2002. Antifungal activities of several plant e xtracts against wheat leaf rust. The Korean Journal of Pesticide Science 6(2): 87-95. In Korean). One main difference was that each plant pathogen was inoculated 3 days afte r treatment of the plant with each composition with 200-fold dilution by spraying on plant surfaces. Treated plants were maintained by general practice, and plant protection acti vity was estimated by control value. Control value (CV) is estimated by the following for mula; CV(%)= {1 -(diseased area ratio of treatment group/diseased area ratio of non-tre atment group)}x100.

Table 3.

Protection activity of each composition and beneficial microorganism against plant dise ases

RCB^A) Rich blast caused by Maganaporthe grisea

RSB^B) Rich sheath blight caused by Thanatephorus cucumeris

TGM^C) Tomato gray mold caused by Botrytis cinerea

TLB^D) Tomato late blight caused by Phytophthora infestans

WLR^E) Wheat leaf rust caused by Puccinia recondita

BPM^F) Barley powdery mildew caused by Blumeria graminis f. sp. Hordei

In Table 3, SAP compositions of the present invention in general showed protecti on activity against the plant diseases that resulted in increased control value. More spe cifically, overall increase in control value by the composition 1 was observed for all the diseases. Overall increase of control value by the composition 2 was also observed for all the diseases. The composition 2 resulted in somewhat higher control values than the composition 1. Overall increase of control value was also observed with the compositio n 3 to composition 11. Especially, control value was improved for the compositions that showed protection activity against plant diseases only with each of beneficial microorga nisms. The beneficial microorganism 1 by itself showed protection activity against tomat o late blight (TLB) and tomato gray mold (TGM) whereas the composition 3 containing t he beneficial microorganism 1 showed improved protection activity against the same dis eases and additionally showed a certain protection activity against rice blight (RCB), ric e sheath blight (RSB), wheat leaf rust (WLR) and barley powdery mildew (BPM). The b eneficial microorganism 2 by itself showed protection activity against TLB and BPM, wh ereas the composition 4 containing the beneficial microorganism 2 showed improved pr otection activity against TLB and BPM and additionally showed a certain protection acti vity against other diseases. The beneficial microorganism 3 by itself showed protection activity against RCB, RSB, TGM and TLB, whereas the composition 5 containing the be neficial microorganism 3 showed improved protection activity against RCB, RSB, TGM and TLB and additionally showed a certain protection activity against other diseases. T he beneficial microorganism 4 by itself showed protection activity against WLR and BP M, whereas the composition 6 containing the beneficial microorganism 4 showed impro ved protection activity against WLR and BPM and additionally showed a certain protecti on activity against other diseases. The beneficial microorganism 5 by itself showed prot ection activity against TGM and RSB, whereas the composition 7 containing the benefic ial microorganism 5 showed improved protection activity against TGM and RSB and ad ditionally showed a certain protection activity against other diseases. The beneficial mic roorganism 6 by itself showed protection activity against BPM and WLR, whereas the c omposition 8 containing the beneficial microorganism 6 showed improved protection act ivity against BPM and WLR and additionally showed a certain protection activity against other diseases. The beneficial microorganism 7 by itself showed protection activity aga inst TLB and RSB, whereas the composition 9 containing the beneficial microorganism 7 showed improved protection activity against TLB and RSB and additionally showed a certain protection activity against other diseases. The beneficial microorganism 8 that h as protection activity against insect larva of Plutella species did not show any protection activity against the plant diseases, whereas the composition 10 showed containing the beneficial microorganism 8 showed a certain protect activity similar to the composition

2 against the plant diseases. The beneficial microorganism 9 that induces disease resis tance by itself showed protection activity against BPM and WLR, whereas the compositi on 11 containing the beneficial microorganism 9 showed improved protection activity ag ainst BPM and WLR and additionally showed a certain protection activity against other diseases. As described above, each of the compositions of the present invention in gen eral showed higher control value than each of the microorganisms. The composition 1 o r composition 2 not comprising the beneficial microorganisms also showed a certain lev el of increased control value.

However, considering the Example 2 that was conducted in a system which is u sually employed for the evaluation of chemical pesticides for short periods in growth ch amber that was established with stable conditions including temperature, humidity and Ii ghting for disease development or insect growth, there was a certain limitation to confir m protection activity. Thus, in order to confirm protection activity of the compositions of t he present invention against plant disease, natural condition is considered more desira ble because of plant surfaces to be exposed to fluctuating moisture, temperature and Ii ghting in day and night. Plants can be also grown for longer period. Therefore, for better confirmation of the effect of the present invention, by using adult plants under general conditions for cultivation or similar conditions, an experiment was further carried out rep eatedly to confirm the efficacy of the composition of the present invention.

Example 3: Protection activity against cucumber powdery mildew and populatio n dynamics of microbial population

Of the compositions of the present invention, some compositions were confirmed for their protection activity against cucumber powdery mildew caused by Sphaerotheca fusca that naturally occur on adult plants in a green house. Cucumber seedlings grown for 1 month after seeding were transplanted into pots (15 cm in diameter, 20 cm in dep th) that were filled with a fertile soil (Bunong Sangto No. 5) manufactured by Biomedia, Korea, and additionally grown until cucumber plants grew up to the fifth or sixth leaf sta ges by general practice in the green house. Then, water suspension of the composition s 1 , 2, 3 and 4, the beneficial microorganisms 1 and 2, and a chemical fungicide with ac tive ingredient azoxystrobin were respectively sprayed on cucumber surfaces and leave s with 7 days of application interval for comparative studies. The experiments were prep ared by randomized complete block design with three replications. Four cucumber plant s were included for each replication. Spray suspension comprises each composition of t he present invention or the beneficial microorganisms that are 200-fold diluted with wat er. Each beneficial microorganism was prepared to have similar number of beneficial mi croorganisms when diluted with the same amount of water. Spray suspension was suf ficiently applied on cucumber leaves and surfaces by hand-held sprayer until the suspe nsion drops off plants. Cucumber powdery mildew was induced to occur naturally on a f ew cucumber plants in the green house. In fact, the occurrence of the disease was obs erved when cucumbers reached the fifth or sixth leaf stage. Protection activity was est imated on the day of each application according to a guideline of Rural Development A dministration, Korea. Additional estimations were made on the seventh and fourteenth days after treatment 3 (7 DAT 3 and 14 DAT 3). The protection activities against cucum ber powdery mildew were given in Table 4.

Table 4.

Protection activity against cucumber powdery mildew

^A) Chemical fungicide with azoxystrobin as active ingredient

^B)The same letters in each column are not significantly different by Duncan's multiple ra nge test at P=0.05. As shown in Table 4, the compositions 1 and 2 resulted in a certain level of protection a ctivity. The compositions 3 and 4 showed improved protection activities when compared with each beneficial microorganism. The chemical fungicide, azoxystrobin, did not sho w good protection activity for this test. This was considered due to resistance of pathog en to fungicide azoxystrobin.

In parallel, microbial populations on cucumber leaves were also monitored. On th e same day prior to each application using a cork borer, three leaf discs (3 cm in diamet er) were collected from the third main leaf of cucumber plant for each treatment. The co llected leaf discs were put into 10 ml of sterile water for 30 minutes and shaken hard by hand to prepare the leaf wash water. Microbial population was measured by 10-fold seri al dilution plating method or using LB agar medium. The beneficial microorganisms wer e counted on the basis of their own unique colony forms on the LB agar media. The res ult is given in Table 5.

Table 5.

Population dynamics of microorganisms on cucumber leaf surface

^B) NM = Natural microorganisms

^C) BM = Beneficial microorganisms

In Table 5, microbial population density when treated with the compositions was significantly increased when compared to the treatments only with each beneficial micr oorganism. Especially, for the composition 2, population density of natural microorganis ms was increased 100 times, when compared with the non-treatment. Also microbial po pulation of the composition 2 was in overall higher than that of the composition 1. Furth er, the composition 3 containing the beneficial microorganism 1 and the composition 4 c ontaining the beneficial microorganism 2 showed a certain activity to reduce population density of natural microorganisms. This trend indicates that the protection activities in T able 4 were due to increased population density of each beneficial microorganism. This experiment also confirms that population dynamics of microorganisms shown in Table 5 was similarly reproduced with adult cucumber plants in the green house.

Example 4: Protection activity from harmful insects

Composition 10 of the present invention was tested in a laboratory to evaluate in secticidal activity to diamondback moth (Plutella xylostella) that harms plants belonging to Cruciferae. Cabbage seedlings were grown in a green house, and their leaf discs (5 c m in diameter) were sampled and soaked for 30 seconds in suspension of the composit ion 10 that was 2000-fold diluted. Those leaf discs were taken out and dried in shade in a hood. Ten larvae of Plutella xylostella that had been grown up to the third stage larv ae were placed on the leaf discs and assessed for insecticidal activity at 24, 48, 72, 96 and 120 hours after the placement. The experiment was prepared by randomized block design with three replications. The insecticidal activity was assessed according to a gui deline of Rural Development Administration (Korea). The result is given in Table 6.

Table 6.

Insecticidal activity against diamondback moth (Plutella xylostella)

^A) lnsecticidal activity (%) is percentage of dead larvae at each time.

^B) Hours after placement on the leaf discs

^C)The same letters in each column are not significantly different by Duncan's multiple ra nge test at P=0.05.

As shown in Table 6, the composition 10 of the present invention resulted in 100 % of insecticidal activity at 72 hour after the treatment. The insecticidal activity was sign ificantly higher than the case in which the beneficial microorganism 8 was used alone. F urthermore, time to reach 100% of insecticidal activity was shorter for the composition 1 0 than for the beneficial microorganism 8.

This example indicates that the compositions of the present invention can be ap plied not only for the plant protection from plant pathogens but also for the plant protecti on from harmful insects. In a similar approach, the compositions of the present inventio n are considered to be useful for extended use by increasing population of beneficial mi croorganisms to suppress harmful organisms such as cockroaches, ants, snails and so on.

Example 5: Herbicidal activity

When some plant pathogens specifically infect limited number of weedy plants, c ompositions of the present invention that contain these plant pathogens can be used to suppress or control weedy plants. In this example, tomato was taken as an example of weedy plants. The compositions 1 and 2 of the present invention that contain spores of

Botrytis cinerea at 8.00 log cfu/ml were respectively diluted at 200-fold rate and sufficie ntly sprayed with 50 ml for each tomato seedling until dropping off. Herbicidal activity w as estimated with a similar method used in the Example 2. Herbicidal activity was estim ated at 3 and 7 days after inoculation (3 DAI and 7 DAI) based on percentage of infecte d leaf area. The result is given in Table 7.

Table 7.

Herbicidal activity against tomato seedlings

As shown in Table 7, compositions of the present invention can be used to supp ress weedy plants. More specifically, the treatment of the compositions 1 and 2 resulted in more severe occurrence of the disease to the tomato seedlings than the treatment o nly with Botrytis cinerea. However, in the case of using weed pathogens, weedy plants need to be defined specifically and the weed pathogens need to have high selectivity in pathogenesis. If not, weed pathogens may cause diseases to crops or plants because weeds are also plants. Lee et al. reported a similar result (Boyoung Lee, Dalsoo Kim, a nd Choong-Min Ryu. 2008. A super-absorbent polymer combination promotes bacterial aggressiveness uncoupled from the epiphytic population. Plant Pathology Journal 24:28 3-288). Inventors of the present invention showed that a composition of the present inv ention can improve aggressiveness of a bacterial plant pathogen to tomato seedlings. INDUSTRIAL APPLICABILITY

The present invention is industrially valuable in that it provides a composition that can supplement or replace chemical pesticides or chemical fertilizers and the use ther eof.

Claims

1.

A composition comprising SAP (super absorbent polymer) to improve biological activity or to increase microbial population of microorganisms that exist on surfaces.

2.

The composition according to Claim 1 , characterized in that it additionally compr ises at least one microbial nutrient that can be utilized by the microorganisms.

3.

The composition according to Claim 1 , characterized in that it additionally compr ises at least one beneficial microorganism that can inhibit growth of plant pathogens, ha rmful insects or weedy plants or can promote plant growth.

4.

The composition according to Claim 1 , characterized in that it additionally compr ises at least one beneficial microorganism that can inhibit growth of harmful animals.

5.

The composition according to any one of Claims 1 to 4, characterized in that it a dditionally comprises at least one surfactant to improve spreadability of the composition on surfaces.

6.

The composition according to any one of Claims 1 to 4, characterized in that it a dditionally comprises at least one single or complex mineral salt to improve wettability o f the composition in water.

7.

The composition according to any one of Claims 1 to 4, characterized in that sai d SAP is SAP made from starch.

8.

The composition according to any one of Claims 1 to 4, characterized in that the content of SAP is the range of 20% to 95% by weight of the composition.

9.

The composition according to any one of Claims 1 to 4, characterized in that the content of SAP is the range of 0.02% to 1.0% by weight per water volume when the co mposition is diluted with water.

10.

The compositions according to any one of Claims 1 to 4, characterized in that sai d surface is selected from plant surfaces such as leaf, stem, branch or fruit surface, soil surfaces or animal skin surfaces.

1 1 .

The composition according to Claim 2, characterized in that said microbial nutrie nts are composed of PLNT media that includes potato dextrose broth, Luria broth base, nutrient broth and tryptic soy broth each in the amount of 25% by weight based on thei r standard use amount.

12.

The composition according to Claim 3, characterized in that said plants are selec ted from the group consisting of cucumber, pepper, potato, rice, tomato, barley, wheat, pear and rose.

13.

The composition according to Claim 3, characterized in that said beneficial micro organisms are selected from the group consisting of genus Bacillus, genus Paenibacillu s, genus Streptomyces, genus Trichoderma, genus Ampelomyces and genus Acremoni urn.

14. The composition according to Claim 3, characterized in that said plant pathogens are selected from the group consisting of Magnaporthe grisea, Thanatephorus cucume ris, Phytophthora capsici, Botrytis cinerea, Puccinia graminis, Blumeria graminis( = Erys iphe graminis) and Sphaerotheca fusca.

15.

The composition according to Claim 3, characterized in that said harmful insects are selected from genus Plutella.

16.

The composition according to Claim 3, characterized in that said weedy plants ar e selected from plants that grow at time and place that plant growers do not desire.

17. The composition according to Claim 4, characterized in that said harmful animals are selected from the group consisting of cockroach, ants and snails.

18.

Use of the composition according to any one of Claims 1 to 4 on plant surfaces i ncluding leaf, stem, branch, flower or fruit, or soil surfaces on which lawn grasses grow.

19.

Use of the composition according to any one of Claims 1 to 4 to inhibit harmful or ganisms on surfaces or to promote plant growth.