Seed priming with plant gum biopolymers enhances efficacy of metalaxyl 35 SD against pearl millet downy mildew
- 197 Downloads
‘Priming’ the plant and seed induces a physiological state in which plants are able to activate defense responses. Plant-based exudates are excellent gum biopolymers which contain plant growth-regulating hormones with priming potential without any side effects. In this study, gum exudates of Acacia arabica, Moringa oleifera, Carica papaya and Azadirachta indica were evaluated for synergistic effects of seed priming with exuded gum biopolymer combined with metalaxyl (Apron 35 SD) on pearl millet seed quality, growth parameters, and resistance to Sclerospora graminicola. Seeds of 7042S were primed with gum biopolymers and metalaxyl 35 SD and evaluated under laboratory and greenhouse conditions. Seed germination and vigor were synergistically enhanced using gum biopolymers solution (1:2 w/v) with 3 g kg−1 metalaxyl 35 SD. A. arabica and A. indica gum biopolymers alone or with 3 g kg−1 of metalaxyl 35 SD resulted in seed germination of >91%. Seed priming with 6 g kg−1 of metalaxyl 35 SD gave 89% seed germination and was not significantly different from control. A similar trend in vigor was observed among treatments. Seed priming with gum biopolymers alone provided varied disease protection levels when compared with the control. A. arabica or A. indica gum with 3 g kg−1 of metalaxyl 35 SD was the superior treatment, offering significant 86% disease reduction while exhibiting a growth-promoting effect. Synergistic use of gum biopolymers and metalaxyl 35 SD by seed priming is highly effective in growth promotion and management of pearl millet downy mildew disease.
KeywordsBiopolymer gums Downy mildew management Pearl millet growth promotion Seed pelleting
- Agarwal, V. K., & Sinclair, J. B. (1997). Principles of seed pathology. Boca Raton, FL, USA: CRC.Google Scholar
- Ali, N. I., Siddiqui, I. A., Shaukat, S. S., & Zaki, M. J. (2001). Survival of Pseudomonas aeruginosa in various carriers for the inhibition of root rot–root knot disease complex of mungbean. Phytopathologia Mediterranea, 40, 108–112.Google Scholar
- Anonymous (1993). International rules for seed testing. Seed Science and Technology, 13, 309–333.Google Scholar
- Elzein, A., Fen, B., Avocanh, A., Kroschel, J., Marley, P., & Cadisch, G. (2007). Compatibility of Striga-mycoherbicides with fungicides delivered using seed treatment technology and its implication for Striga and cereal fungal diseases control. Abstracts Tropentag (Witzenhausen, Germany).Google Scholar
- Maude, S. J. (2002). The effects of surfactant and water volume on the coverage of seed surface by a seed treatment formulation. Brighton Crop Protection Conference Pests and Diseases, 2, 507–514.Google Scholar
- Mohanan, C., & Sharma, J. K. (1991). Seed pathology of forest tree species in India—present status, practical problems and future prospects. Commonwealth Forestry Review, 70, 133–151.Google Scholar
- Prakash, K. J., Suresh, N., & Babu, C. R. (2007). Development of an inexpensive legume-Rhizobium inoculation technology which may be used in aerial seeding. Journal of Basic Microbiology, 34, 231–243.Google Scholar
- Safeeulla, K. M. (1976). Biology and control of the downy mildews of pearl millet, sorghum and finger millet. Mysore, India: Wesley.Google Scholar
- Singh, S. D., & Gopinath, R. (1985). A seedling inoculation technique for detecting downy mildew resistance in pearl millet. Plant Disease, 69, 425–428.Google Scholar
- Singh, S. D., & Shetty, H. S. (1990). Efficacy of systemic fungicide metalaxyl for the control of downy mildew (Sclerospora graminicola) of pearl millet (Pennisetum glaucum). Indian Journal of Agricultural Science, 60, 575–581.Google Scholar
- Sudisha, J., Roopa, K. S., Pushpalatha, H. G., & Shekar Shetty, H. (2008). Evaluation of plant growth-promoting rhizobacteria for their efficiency to promote growth and induce systemic resistance in pearl millet against downy mildew disease. Archives of Phytopathology and Plant Protection. doi: 10.1080/03235400701806377.
- Williams, R. J., Singh, S. D., & Pawar, M. N. (1981). An improved field screening technique for downy mildew resistance in pearl millet. Plant Disease, 65, 239–241.Google Scholar