Department of Agriculture, Government of Madhya Pradesh, Gwalior.
At Gwalior, both in the laboratory and in the field, Galerucella birmaniea Jacoby the most serious pest of Singhara (Trapa bispinosa or water-nut) continued to breed throughout the off-season i.e. December to May. Enough Singhara plants (remnants of the previous year's crop and volunteer plants) were seen in the field during the entire off-season for the carry-over of this pest. Without food the beetles died quickly. The beetles may hide in the cracks etc. during short spells of severe cold. There was no diapause or hibernation. It is concluded that hibernation may not be necessary for the carry-over of this pest from one crop season to another at Gwalior or elsewhere in the Indian plains. This conclusion is at variance with that of Khatib (1934) and Srivastava (1956).
Studies on the rate of development of G. birmaniea during the different months and the effect of temperature on the rate of development have also been completed and will be reported upon elsewhere.
