Studies on Management of Seed Borne Inoculum of Bakanae (Fusarium Moniliforme Sheld.) of Rice

Abstract

Rice ( Oryza sa~iva), is th~ mos~ wide~y consumed staple food for a large part of the world's human pop~lati~n, especially m Asia. Among various varieties of rice grown in India Basmati v?IIety Is. on~ of the most popular variety with its characteristic texture and arom<.· The low yield ~f nee IS associated w~th poor management practices, unavailability of quali~ s~eds and s~ecially lack of.proper disease management. Diseases play an important role in yield reduction. Bakanae disease of rice is among such diseases which are responsible f01 considerable yield reduction of rice including in Basmati variety also. This disease of rice is basically a seed borne disease and causes severe loss in the field. Increase in height of infected seedlings and rotting of the foot region of the infected tillers are the typical sypmptoms of this disease. For estimation of infection percentage of Bakanae in different varieties of rice blotter method was used in which variety PB1121 showed the highest infection percentage (19%) while PS5 showed only 3.33% infection. Biopriming of seeds with talc formulation of Trichoderma viridae, Pseudomonas j/uroscence and T. harzianum was found to be significantly effective in controlling the seed borne inoculums and othe• seedling growth parameters in rolled paper towel and grow on test. T. viridae @of I Ogmlk/ for 12 hrs treatment gave the best result in .all parameters like germination percentage' infection percentage, seedling vigor index, shoot length, root length , shoot weight and roo! weight which was followed by T. harzianum.@ 10 gmlkg for 12 hrs. The results showed that higher dose of treatment for longer duration were able to have good impact on seedlings as compared to lower dose for short duration. Out of 7 fungicides tested for their efficacy against F. moniliforme in vitro by poisoned food technique, propiconazole, hexaconazole, Tebuconazole and carbendazim @ 0.1 %, and vitavex @ 0.2% completely inhibited the growth of pathogen while thiram and captan@ 0.2% were able to inhibit by 75.93% and 74.07% respectively. In comparison of effect of different fungicides and biopriming agents against pathogen infection and seedling growth, the biopriming agent T .. viri~ae @ 10 grn/ kg for 12 hrs was found to be superior in increasing germinatio~, s~ed.lmg ~Igor, root ar.. shoot length as well as root and shoot weight but in case of redUction m Infection percentag~ the seed treated with fungicide propiconazole was lowest followed by hexaconazole