Studies on Leaf Crinkle Disease of Greengram and Blackgram

Abstract

Leaf crinkle is an important viral disease reduces yield and quality of seeds. newlineRoving survey showed the highest mean PDI in Yadagir (45.20% and 42.50%) and newlinelowest in Haveri (17.17% and 16.89%) in greengram and the highest mean PDI in Bidar newline(39.13% and 42.87%), lowest mean PDI recorded in Haveri (21.20% and 19.60%) in newlineblackgram during 2011 and 2012, respectively. newlineVirus was transmitted mechanically (26.66% and 20.00%), by insect vector newlineAphis craccivora (20.00% and 13.33%) and seed (19.89% and 14.97%) in blackgram newlineand greengram, respectively. EM revealed the small isometric virus particles of size 28 - newline32 nm. The recorded TIP, DEP and LIV were between 55 °C -60 °C, 1:1000-1:10000 newlineand 48-60 hr, respectively. Raised polyclonal antiserum was cross adsorbed and titre of newlinethe antiserum was 1:16 against antigen at 1:8 dilutions. Antibody dilution of 1:5 and newlinesample dilution of 1:1 were successfully standardized by DAC-ELISA and further it newlinewas employed to test in different field samples. A separate faint RNA band in infected newlinesamples indicated RNA natured casual agent. TSV, BCMV, SYMMV and Deng newlineprimers not amplified the crinkle disease samples. Hence casual agent of leaf crinkle newlinedisease was distinct from above. newlineIn greengram weather parameters correlated with PDI and aphids nonsignificantly newlineexcept aphids with RH 1 and in blackgram except PDI with RH 1 and newlineaphids with Tmin and RH 1, all other parameters were non-significant during kharif newline2011 and 2012. In both without and with border crop experiment in greengram and newlineblackgram, among the treatments T6 (heat therapy of seeds + seed treatment with newlineImidacloprid 600 FS + spray with Imidacloprid 17.8 SL at 25 DAS) was the best newlinetreatment with highest yield, B:C ratio and net profit. During screening some of the newlinelines showed moderately resistant reaction to leaf crinkle virus in greengram and newlineblackgram. newline