VARIETAL SCREENING AND MANAGEMENT OF UFRA DISEASE OF RICE

Abstract

A total of 52 rice entries were tested, 4 entries, namely FUKUHONAMI, MATSUHONAMI, AKIYU TAKA, HA YAKlKARI and showed highly resistance (HR) reactions to ufra, 9 entries viz. IR30, AOKAZI, KOSHINISHINI,' KINONISHIKI, AKINISHlKI, SHINANOKOGANE, HUNENW ASE, RA YEDA4849 and RA YEDA4851 showed resistant (R) reactions, 30 showed intermediate or moderate resistance (IRJMR) reactions and 9 showed susceptible (S) reactions to ufra. The entries belonging to the HR· and R groups had a low number of infested tillers with or without symptoms. Effectiveness of Furadan 5G in soil was evaluated against ufra disease of rice at different intervals of application. The ufra infestation was lower and the number of healthy panicle was higher at the application of Furadan 5G just at transplanting. The infestation was significantly reduced at the application of Furadan 5G up to 20 days before transplanting. The length of effectiveness of Furadan 5G in soil was 20 days approximately. Therefore, in controlling ufra and increase yield, Furadan 5G @ 1kg ai/ha should be incorporate into the soil at transplanting. Three granular nematic ides namely Cemifuran 5G, Edfuran 5G and Brifar 5G @ 1kg ai/ha were evaluated against ufra disease of rice in comparison with Furadan 5G. In T. Aman and Boro, 2005-2006, the damaged tillers and total ufra were significantly higher in the control (diseased) plots compared to control (healthy) or nematicidal treatments. Accordingly, Cemifuran 50, Edfuran 5G and Brifar 5G treated plots had 37.53-52.74% apparently healthy panicles with 3.56-4.02 t/ha yield in T. Aman while those nernaticides had 31.66-52.98% healthy panicles with 3.37-3.59 t/ha yield in Boro season. The obtained yields of three nematicides (3.56-4.02) were close to control (healthy) treatment (4.48 t/ha) in T. Aman. A considerable yield increase (3.37-4.02 t/ha) was also observed in three new nematicides over the control (diseased) treatment in both seasons. However, the test nematic ides could be used in controlling ufra disease incidence and also increasing yield of rice.