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All the cultivated Brassica species exhibited powdery mildew severity with highest (43.2%) on Brassica juncea followed by B. rapa (28.0%) which is widely cultivated in India. Yield losses from 10-90 per cent with reduction in 6.47 per cent oil content have been estimated from different Brassica species. Hence, the present study was carried out to evaluate different oils to manage powdery mildew disease and aphids in an organically grown mustard crop. Five oils (castor, groundnut, sunflower, neem and mustard oil) and ghee were evaluated against powdery mildew (Erysiphae cruciferarum) and aphid (Lipaphis erysimi) of Indian mustard (Brassica juncea). Castor oil 50 EC, neem oil 50 EC and mustard oil 50 EC and deshi ghee 50 EC (@ 100 ml/10 litre water) were effective over untreated control in reducing powdery mildew disease severity when applied as foliar spray (@ 5 ml/litre) in the experiment carried out in organic field (plot No. B-2 at Agronomy Instruction Farm, S. D. Agricultural University, Sardarkrushinagar). Maximum reduction in germinated conidia (66.0%) over control, disease severity (50.0%), area under disease progress curve (AUDPC) values (51.8%) and maximum increase over control in 1000 seed weight (16.7%) and seed yield (10.3%) was observed with neem oil. This was followed by the application of ghee which exhibited reduced disease severity (22.9%) and AUDPC values (30.6%) and increased seed yield (8.1%) and the application of castor oil 50 EC which exhibited an increased in seed yield (8.0%) and reduced powdery mildew severity (20.8%). Shortest log phase was observed with neem oil during 10th std. week. All the oils tested (castor, groundnut, sunflower, neem and mustard oil) and deshi ghee were effective in reducing aphid population (39.5 to 65.9%) and damage index (6.1 to 25.1%). A maximum reduction in aphid population (65.9%) over control and lowest aphid damage index (3.70) was observed with neem oil 50 EC 6 days after 2nd spray. Application of neem oil

Field experiment was conducted at Regional Research station, Samargopalpur, Rohtak (Haryana) during Rabi season of the year 2015-2016 to evaluate bioefficacy of various treatments against mustard aphid, Lipaphis-erysimi on Indian mustard. Treatments were: T1–Verticillium lecanii @ 108 CS/ml, T2–Beauveria bassiana @ 108 CS/ml, T3 - Neem seed kernel extract @ 5%, T4 - Neem seed methanol extract @ 5%, T5 - V. lecanii @ 108 CS/ml + Clipping of infested twigs, T6 - B. bassiana @ 108 CS/ml + Clipping of infested twigs, T7 - NSKE @ 5% + Clipping of infested twigs, T8 - V. lecanii @ 108 CS/ml + NSKE @ 5%, T9 - B. bassiana @ 108 CS/ml + NSKE @ 5%, T10 - Dime-thoate 30EC @ 250 ml/acre. Dimethoate was found to be most effective in reducing the aphid population (95.03 %) followed by V. lecanii @ 108 CS/ml + NSKE @ 5% (88.52 %), NSKE @ 5% + Clipping of infested twigs (87.77 %) and B. bassiana @ 108 CS/ml + NSKE @5% (86.91 %) after ten days of spray. The highest seed yield was recorded in treatment dimethoate 30EC (1702 kg/ha) followed by V.lecanii @ 108 CS/ml +NSKE @ 5% (1635 kg/ha), NSKE @ 5% + Clipping of infested twigs (1626 kg/ha) and B.bassiana @ 108 CS/ml + NSKE @ 5% (1617 kg/ha). Dimethoate was found to be highly cost effective with highest cost benefit ratio (1:14.92) followed by NSKE @ 5% + clipping of infested twigs (1:13.81) and NSKE @ 5% (1:11.41).

Four bioagents, viz., Coccinella septempunctata L., Menochilus sexmaculatus (F.), Chrysoperla carnea (Stephens) and Verticillium lecanii (Zimmerman), were evaluated against mustard aphid, Lipaphis erysimi (Kaltenbach), on single plants covered with muslin cloth in the field at National Research Centre on Rapeseed-Mustard, Sewar, Bharatpur (Rajasthan) during 2005-06 and 2006-07. C. septempunctata @ two adults/plant was found to be the most effective, reducing 96.19% of the aphid population in 10 days followed by C. septempunctata @ two larvae per plant (93.42%), V. lecanii @ 108 spores-ml (84.90%), M. sexmaculatus @ two adults (84.62%) and C. carnea @ four larvae-plant (82.98%). C. septempunctata @ one adult per plant reduced the aphid population by 77.49% and M. sexmaculatus by 69.08%.

Three bio-agents viz., Coccinella septempunctata (Linnaeus), Chrysoperla carnea (Stephens) and Verticillium lecanii (Zimmerman) were evaluated against mustard aphid Lipaphis erysimi (Kaltenbach) under net covered condition in the field at National Research Centre on Rapeseed-Mustard, Sewar, Bharatpur (Rajasthan), during 2005-06 and 2006-07. C. septempunctata @ 5,000 beetles/ha was found to be most effective by reducing 88.17 percent aphid population after 10 days of release, followed by V. lecanii @ 108 spores/ml (75.79 percent) and C. septempuactata @ 3,000 beetles/ha (65.46 percent), Maximum yield was recorded with the release of C. septempunctata @ 5,000 beetles/ha followed by V. lecanii @ 108 spores/ml and C. septempunctata @ 3,000 beetles/ha.