Department of Entomology, Punjab Agricultural University, Ludhiana
Emulsifiable concentrate (EC) and Low volume concentrate (LVC) formulations of malathion and fenitrothion were applied from the ground in high volume (HV), low volume (LV) and ultra-low volume (ULV) sprays for the control of aphids, jassids and whitefly on potato. ULV sprays proved most promising for the control of aphids and whitefly. In case of jassids, however, these sprays did not prove significantly better than LV and HV sprays. Malathion and fenitrothion largely did not differ in their effectiveness and persistence in controlling pests on potato. Low dosages of fenitrothion (0.1 kg A.I./ha) and malathion (0.3 kg A.I./ha) than their medium dosages (0.3 kg A.I./ha and 0.5 kg A.I./ha, respectively) proved significantly inferior in controlling aphids and jassids. The differences in the mortality of pests with the medium dosages and high dosages of fenitrothion (0.5 kg A.I./ha) and malathion (0.7 kg A.I./ha) were non-significant. However, in case of whitefly, the high dosages were significantly better than medium dosages which in turn were more effective than low dosages.
