Efficacy of Different Pesticides against Mustard Aphid, Lipaphis Erysimi in Selected Mustard Cultivars

Abstract
| Mustard Aphid ( Lipaphis erysimi ) (Homoptera: Aphididae) is a destructive insect pest that causes significant losses in the yield of canola crops. It is essential to find out the management strategies of this pest for higher canola production. Synthetic insecticides and bio-pesticides are used to control L. erysimi . The present study evaluated the efficacy of different pesticides against mustard aphids in selected mustard cultivars under field conditions. The experiment was carried out in Split Plot Design with four treatments and three replications. The results showed that Thiamethoxam, Fipronil and Neem oil were effective against mustard aphids. After the first spray, the minimum mean numbers of aphids were recorded (8.49) on a variety of China in a plot treated with Thiamethoxam. In contrast, the maximum mean number of aphids was observed (28.80) in the control plot. In the case of cultivar, Swabi the highest mean numbers of aphids were noted (53.86) in an untreated plot, whereas the lowest mean numbers of aphids were found (19.72) in Thiamethoxam treated plot, respectively. After 2 nd spray in cultivar China the lowest aphid was (7.45) in the thiamethoxam treated plot, while the maximum mean numbers of aphids were (29.97) in the check plot, respectively. Compared with cultivar Swabi more numbers of aphids were recorded (47.94) on the control plot, while the least numbers of aphids were recorded (23.80) in a plot treated with thiamethoxam, respectively. In cultivar, China the maximum yield (1064.6) kg/ha was obtained from a thiamethoxam treated plot, while the minimum yield was recorded (562.5) kg ha -1 in control plots. Compared with cultivar, Swabi maximum yield (8.16.7) kg/ha was obtained from a thiamethoxam treated plot, and minimum yield (327.1) kg/ha was also recorded in the control plot. Thus overall results indicated that chemical, thiamethoxam along with resistant variety (China) were superior over rest of the all treatments that reduced the aphid and increased the yield productions, whereas regression of the slop of the tested insecticides based IPM strategy is to be applied for aphids control measure in canola crop.