Effect of date of sowing and seasonal variations on the incidence of yellow mite (Hemitarsonemus latus Bank) infesting different varieties of jute

Field trials were conducted during two years (1991–92 and 1993–94) with olitorius varieties, viz., JRO 524, JRO 632 and JRO 36E, and capsularis varieties, viz., JRC 212, JRC 7447 and Hyb. C. These were sown during the 4th week of March, and 2nd and 4th week of April. Earlier date of sowing, in general, showed higher infestation, whereas the third date of sowing invariably had the lowest incidence. In the case of olitorius varieties, there was no difference in the pest incidence between the first and second date of sowing. The yield was higher in the second date of sowing in all the varieties, except the olitorius variety JRO 524. Considering the yield as well as mite infestation, the second week of April sowing appeared to be the most suitable for all the varieties, except JRO 524 for which fourth week of March was suitable. Differences in the incidence of mite as also yield may be attributed to variations in weather parameters in two seasons.