Whitefly (Aleurolobus Barodensis Mask.) Population Dynamics on Sugarcane in Pakistan

In the present study, three farmer's fields of sugarcane of 10–15 km radius in the vicinity of Chinar, Ashraf and Jamal Din Wali sugar Mills in Faisalabad, Bahawalpur and Rahim Yar Khan, respectively were selected to evaluate the whitefly Aleurolobus barodensis Mask., population dynamics. The distance between these localities was 450 to 500 km. The population (nymphs and adults) was recorded at fortnight intervals during 2008 and 2009 from April to December. The data were also correlated with the weather factors (temperature, humidity and rainfall). The results revealed that populations varied significantly (P<0.05) between periods and locations, it appeared during 2^nd fortnight of June in district Faisalabad and Bahawalpur, while in district Rahim Yar Khan it appeared during 1^st fortnight of July. The peak mean population was recorded on 1^st fortnight of November in district Faisalabad (7.96/leaf) and Rahim Ya r Khan (14.94/leaf), while on 2^nd fortnight of October in district Bahawalpur (15.81/leaf). The district Rahim Yar Khan showed maximum population (4.61/leaf), while in the district Faisalabad it was low (2.48/leaf). The relative humidity had positive and significant (P<0.05) correlation with the population and it increased the population up to 42.3%, 43.8% and 35.9% in Faisalabad, Bahawalpur and Raheem Ya r Khan districts, respectively and the trend of occurrence was found similar in 2008 and 2009.