SURVEY AND OCCURENCE OF SYRPHID FLY, X. scutellare ONDIFFERENT CROPS

摘要

Survey and occurence of syrphid fly,X scutellare on different crops was carried out in the Department of Entomology, C. P. College of Agriculture, S. D. Agricultural University, Sardarkrushinagar during 2011-12. In mustard, the aphid appeared on the crop from second week of December (5,h week after sowing), while syrphid fly during last week of December (8th week after sowing). The aphid population reached the peak level(3.80 aphid index/plant) during first week of February (13th week after sowing).Where, syrphid fly population was also recorded maximum (2.33 larva/plant). In cabbage, aphid and syrphid fly starts their activity after mid December (6th week after sowing) and reached the peak during last week of January (12th week after sowing) and first week of February (13th week after sowing).ln potato, the aphid infestation commenced from first week of January (9th week after sowing) and reached at maximum during end of the January (12th week after sowing), while syrphid fly became active from 2nd week of January (10th week after sowing) and showed maximum population during first week of February (13th week after sowing).The Indianbean aphid showed its activity in crop from first week of January (9th week after sowing) while the syrphid fly appeared two weeks later (11th week after sowing). Though, maximum population of the pest and predator was noted during second week of February (14th week after sowing).In Lucerne, the aphid and the syrphid fly appeared on the crop during first and 3rd weekof January (9th and 11th week after sowing) and both the predator and prey reached the peak level during 2nd week of February (14th week after sowing).