Management of stem necrosis disease in potato under South Eastern Rajasthan

Abstract

Field experiments were conducted during 2018-19 and 2019-20 to evaluate the efficacy of seven different insecticides against thrips vector and stem necrosis disease in potato. The results based on pooled analysis of two years data, revealed that two sprays of fipronil 5%SC @ 15ml/10L of water recorded minimum per cent disease incidence (PDI) of stem necrosis (9.3%) with maximum reduction in thrips population (93.5%), maximum number of tubers (307) and tuber yield (16.6 t/ha). Fipronil 5%SC @ 15ml/10L water was found at par with two sprays of diafenthiuron 50 WP @ 10 g/10L of water i.e. 14.0 PDI, 86.6 per cent reduction in thrips population, number of tubers (296) and tuber yield 17.0 t/ha. Whereas the lowest tuber yield was recorded in untreated control (11.7 t/ha). Highest net return (41552 Rs/ha) with 31.2 per cent yield increase over control and benefit cost ratio (1.46) was obtained with application of diafenthiuron 50 WP @ 10 g/ 10L of water followed by fipronil 5%SC @ 15 ml /10L water (40002 Rs/ha and BC ratio 1.46) with 29.5 per cent yield increase over control.