Combining ability for seed cotton yield and attributing traits in American cotton (Gossypium hirsutum L.)

The present study were conducted in SKUAST-K, Srinager during 2010, and investigations revealed that Common Bacterial Blight was prevalent in all bean growing areas with disease incidence and intensity ranging from 38.55 to 47.69 per cent and 15.05 to 23.84 per cent, respectively. The highest disease incidence of 42.72 per cent and intensity of 23.80 per cent was observed in district Srinagar, while as least incidence and intensity of 39.89 per cent and 17.69 per cent was observed in district Bandipora. Based on the DMRT, the disease intensity and severity recorded were statistically significant across all experimental locations. Symptomatic expression of disease was recorded on leaves, pods, stem, petioles and seeds. Disease initially manifested as minute water-soaked spots on underside of the leaves which gradually enlarged. Later resulting in the coalescing of enlarged spots into brown necrotic patches. The symptoms on pods initially appeared as small water-soaked spots which later enlarged into reddish brown spots and were slightly sunken with raised edges. Symptoms on stem and petiole were initially reddish brown spots, which enlarged along their length in the form of longitudinal streaks. In case of severe infection the streaks girdled the stem. Irregular blotches of various sizes were observed on diseased seed. Such seeds were smaller and appeared dull. Host range studies of bacterium revealed that it successfully infected mung bean, pea, cowpea, lentil, soybean, moth bean, snap bean and lima bean under conditions of artificial inoculation. Infected seeds could harbour the pathogen beyond the next sowing season. The viability of pathogen on infected seeds decreased with time.