Spotted pod borer is one of the major biotic constraint for pulses production which can cause damage to the economic plant parts such as flower buds, flowers and pods. The larvae feeds on 39 host species of legume crops. The seasonal incidence of spotted pod borer differed from crop to crop and season to season. However, the peak incidence of larvae was observed at flowering and pod development stage in different pulse crops. Female moths lays flat scaly eggs on floral buds, flowers, leaves, leaf axils, terminal shoots and tender pods. Larvae are translucent with dark brown spots on each segment and larval period lasted from 11 to 21 days and the duration of total life cycle varied from 27 to 36 days on different hosts. The efficacy of chemical insecticides belonging to different groups against spotted pod borer was well established on different pulse crops. Neem products such as neem seed kernel extract (NSKE) or neem oil and biocides like <italic>Bacillus thuringiensis</italic> (Bt) showed different levels of efficacy on different crops.

Background: Mungbean yellow mosaic virus (MYMV) is economically most important disease of greengram reducing grain yields by 20-70%. Whiteflies and thrips are the most important insect pests which transmit the viral diseases MYMV and LCV respectively. The host plant resistance to MYMV disease in greengram genotypes has a great importance. The morpho-physiological and biochemical traits play an important role in host plant resistance against MYMV disease through insect vector resistance.Methods: A field experiment was conducted during rabi 2017-18 and 2018-19 at RARS Lam Guntur in a randomized block design with eight greengram genotypes and replicated thrice under receding soil moisture condition. The experiment was conducted using eight greengram varieties (WGG 42, Pusa Vishal, LGG 607, LGG 630, LGG 601, LGG 610, LGG 460 and LGG 450) obtained from RARS Lam Guntur and the genotype LGG 450 was considered as a susceptible check. The estimation of sugars, phenols, tannins, trichome density and SCMR was done at vegetative and reproductive stages of crop growth.Result: A significant variation was observed among the varieties for all the traits observed at vegetative and reproductive growth stages during both rabi 2017-18 and 2018-19. The total sugar content of the greengram varieties varied from 25.55 to 47.32 mgg-1 FW; the leaf phenolic content values ranged from 12.09 to 26.83 mg g-1 FW and the tannins content of the dried leaf samples ranged from 0.020 to 0.055 mgg-1 DW. The Trichome density of the greengram varieties varied from 75 to 162/cm2 of leaf area and the SCMR values ranged from 35.12 to 58.67. Higher seed yield was recorded in the variety LGG 630 followed by WGG 42 and the lower seed yield was recorded in the variety LGG 450 during rabi 2017-18 and 2018-19. The MYMV resistant varieties showed relatively higher phenolic, tannins content and trichome density and lower total sugar content in the leaf. The total sugar content showed a significant negative correlation with the seed yield. The SCMR value was significantly lower in the susceptible varieties of greengram with higher disease scores.

No abstract

The insect pests and diseases of blackgram continue to pose a serious threat to the plant growth and yield. The sucking pests in blackgram are economically most important that not only cause the direct damage by feeding but also by transmission of different viral diseases. Sucking pest complex in blackgram include an array of sucking pests out of which thrips, whitefly and aphids are the most important. The leaf curl disease caused by GBNV in blackgram is transmitted through thrips. A study was conducted involving 25 blackgram genotypes to screen them against leaf curl disease. The results obtained from the study indicated that the leaf curl disease incidence (%) and thrips population (Number plant -1 ) varied significantly among the genotypes. Late sowing of the crop coincided with higher temperatures, lower relative humidity and high vector population resulting in higher leaf curl disease incidence. The correlation studies indicated that the leaf curl disease incidence (%) was negatively associated with the mean and morning relative humidity (%) and positively associated with mean, maximum and minimum temperatures.

No abstract