Association of important resistance contributing parameters for shoot fly, stem borer and aphid on Rabi sorghum cultivars

Abstract

Sorghum [Sorghum bicolor (L.) Moench] is an important cereal crop in India popularly known as ‘Jawar’ or ‘Great millet’. In Maharashtra about 18 important insect pests have been recorded on sorghum crop. In sorghum major incidence of shootfly, stem borer and sorghum aphid are observed. In screening programme in all thirty two sorghum genotypes including three checks were replicated twice under Randomized Block Design for resistance to mention insect pest. The study, leaf glossiness ranged from 1.0 to 4.0, lower the score higher was the glossiness and vice versa. The resistant check entry IS-18551 (1.0) and IS-2205 (1.6) recorded significantly lower values than values of all other entries. significantly maximum vigour was recorded in resistant check IS-18551 (1.33) and IS-2205 (1.45) which was at par with Surgaon L., IS-40838, Pop sorg-158, IS-24308, Pbn ent.5, IS-17666, PVR-660, Pop sorg-19. The chlorophyll content index at 21 DAE ranged between 27.70 and 37.30 in different sorghum lines. Among the sorghum lines screened, the least chlorophyll content index score recorded in resistant check IS-18551 (27.0) and IS-2205 (27.80), which was at par with lines viz., IS-13721 (28.42), Pop sorgh-158 (28.42), IS-17666 (29.98), Pbn ent.5 (30.15). The maximum height recorded in resistance checks IS-18551 (182 cm) and IS-2205 (179.0 cm). It was however at par with line Tandur-2, IS-17757, IS-26998, IS-17666, SPV-1411 Surgaon L., PVR-660, IS-31420, Pop Sorgh.19 and Pbn.ent.4. The minimum stem tunnelling percentage was recorded in resistant lines IS-18551 (6.40) and IS-2205 (7.20), which were par lines viz.,IS-26998 (7.40), Pop Sorg.-19 (8.40),IS-30970 (8.90), PVR-660 (9.20), Tandur-2 (9.29). Among the followed lines were SPV-1411 (9.60), IS-24308 (10.0), IS-31123 (11.20), IS-17666 (11.80), IS-31420 (12.40), Pop Sorg.-220 (13.60).