Agricultural product microscreen method and apparatus

Abstract

Methods and apparati for screening compounds for agricultural activity has now been developed which employ e.g., intact plants grown in microtiter plates on very small amounts of plant growth media containing a test compound. In comparison to the standard greenhouse screen, the microscreen requires vastly less space, labor, and test compound. However, unlike in vitro screens, responses of intact plants are assayed. Using the microscreen, high-throughput screening of test compounds can be accomplished using whole plant responses as the assay.

What is claimed is: 
     
       1. A method for evaluating at least one compound for its pre-emergent or post-emergent biological activity on plants, the method comprising (a) placing a plant growth medium and at least one seed into contact with each other and into a container having a cross-sectional area measured in the horizontal direction of not greater than 1 cm 2 , the at least one seed being a seed which will germinate into a plant of the genus selected from the group consisting of Ageratum, Alopecurus, Alternifolius, Arabidopsis, Arabis, Artemisia, Asrostis, Browallia, Capsella, Coleus, Cortaderia, Cynodon, Cyperus, Digitalis, Digitaria, Eragrostis, Festuca, Inula, Ipomopsis, Laevis, Lemna, Lolium, Nicotiana, Oxalis, Panicum, Petunia, Pilifera, Platycodon, Poa, Recta, Sagina, Santolina, Thymophylla, and Thymus;   (b) maintaining the container with the medium and at least one seed under conditions such that in the absence of the at least one compound the at least one seed would germinate and the resulting plant would grow,   (c) contacting the at least one compound to be evaluated with the at least one seed before germination thereof or with the plant resulting from the germination of the at least one seed, and   (d) evaluating the subsequent germination or plant growth.   
     
     
       2. The method of claim 1 wherein the evaluation is pre-emergent, said method comprising (a) placing a plant growth medium, at least one compound to be evaluated, and at least one seed into contact with each other and into a container having a cross-sectional area measured in the horizontal direction of not greater than 1 cm 2 , the at least one seed being a seed which will germinate into a plant of the genus selected from the group consisting of Ageratum, Arabidopsis, Arabis, Artemisia, Asrostis, Browallia, Capsella, Coleus, Cortaderia, Cynodon, Cyperus, Digitalis, Digitaria, Eragrostis, Inula, Ipomopsis, Laevis, Lemna, Nicotiana, Oxalis, Panicum, Petunia, Platycodon, Recta, Sagina, Santolina, Thymophylla, and Thymus;   (b) maintaining the container with the medium, at least one compound and at least one seed under conditions such that in the absence of the at least one compound the at least one seed would germinate and the resulting plant would grow, and   (c) evaluating the resulting germination and plant growth.   
     
     
       3. The method of claim 2 wherein the at least one seed is a seed which will germinate into a plant of the genus selected from the group consisting of Arabidopsis, Asrostis, Browallia, Coleus, Digitalis, Digitaria, Eragrostis, Inula, Nicotiana, Oxalis, Panicum and Petunia. 
     
     
       4. The method of claim 3 wherein the at least one seed is a seed which will germinate into a plant selected from the group consisting of Arabidopsis thaliana, Browallia speciosa, Coleus blumei, Digitaria sanguinalis, Nicotiana tabacum, and Petunia hybrida. 
     
     
       5. The method of claim 1 wherein the cross-sectional area of the container is not greater than 1 mm 2 . 
     
     
       6. The method of claim 1 wherein the cross-sectional area of the container is not greater than 4 mm 2 . 
     
     
       7. The method of claim 2 wherein the cross-sectional area of the container is not greater than 0.5 cm 2 . 
     
     
       8. The method of claim 5 wherein the container is one of a plurality of containers substantially the same dimension as each other arranged in a rectangular matrix on a single supporting plate, and wherein the method comprises placing into substantially all of the plurality of containers a growth medium and at least one seed. 
     
     
       9. The method of claim 6 wherein the container is one of a plurality of containers substantially the same dimension as each other arranged in a rectangular matrix on a single supporting plate, and wherein the method comprises placing into substantially all of the plurality of containers a growth medium and at least one seed. 
     
     
       10. The method of claim 7 wherein the container is one of a plurality of containers substantially the same dimension as each other arranged in a rectangular matrix on a single supporting plate, and wherein the method comprises placing into substantially all of the plurality of containers a growth medium and at least one seed. 
     
     
       11. The method of claim 8 wherein the plurality of containers is 9600 in number and they are arranged in a 80 by 120 matrix on a plate having substantially the same footprint as a standard microtiter plate. 
     
     
       12. The method of claim 9 wherein the plurality of containers is 2400 in number and they are arranged in a 40 by 60 matrix on a plate having substantially the same footprint as a standard microtiter plate. 
     
     
       13. The method of claim 10 wherein the plurality of containers is 96 in number and they are arranged in an 8 by 12 matrix on a standard microtiter plate. 
     
     
       14. The method of claim 2 wherein the container having the medium, the at least one compound and the at least one seed are maintained in an atmospheric environment having an elevated carbon dioxide level of at least about 2200 ppm. 
     
     
       15. The method of claim 2 wherein the container having the medium, the at least one compound and the at least one seed are maintained in an atmospheric environment having an elevated carbon dioxide level of at least about 5000 ppm. 
     
     
       16. The method of claim 1 wherein the at least one compound to be evaluated is impregnated on a microsphere and said impregnated microsphere and the growth medium are placed in the container and mixed with each other prior to the at least one seed being placed into the container and into contact with the mixture of the medium and the compound. 
     
     
       17. The method of claim 2 wherein the growth medium and the at least one compound to be evaluated are placed in the container and mixed with each other prior to the at least one seed being placed into the container and into contact with the mixture of the medium and the compound. 
     
     
       18. The method of claim 2 wherein the results of the evaluation were obtained by visual assay taking into consideration germination of the seed, and size, morphology and color of the plant resulting from the germinated seed. 
     
     
       19. The method of claim 2 wherein the results of the evaluation were obtained by using an assay which measures chlorophyll content. 
     
     
       20. The method of claim 2 wherein the results of the evaluation were obtained by using an assay which measures biomass.