Biology, morphology, and varietal distribution of Saw-toothed grain beetle, Oryzaephilus surinamensis (L) on date palm dry and semi-dry dates at district: Khairpur, Sindh - Pakistan

Abstract

The biology of saw-toothed grain beetle, O. surinamensis was assessed on two different dry and semi-dry dates (Aseel and Dadhi) varieties under laboratory conditions at Date Palm Research Institute, SALU-Khairpur during, 2019-20. The results showed that the overall mean of eggs was observed at (60.6310.41) on both varieties and the eggs incubation period (4.090.50), hatching (82.084.42) % which was almost found higher on dry dates. The duration of various larval stages was also observed from 1 st stage larvae to 4 th stage (2.95 to 7.09) in days thus, the mortality and survival rate with % at (4.78 to 46.32) and (3.56 to 88.34) with the pupae period was (12.24). While as; an adult male (10.84) and female (15.91) days consumption and total life spawn (46.78) and (51.86) with a sex ratio (0.90) and (1.11) was remained fluctuated, thereof the maximum infestation on Dadhi dry fruit was observed (9.451.28), semi-dry (9.016.44) and Aseel dry fruit (5.650.73) and semi-dry dates (4.973.02), respectively. The result of the present work indicates that this insect pest frequently relay a negative effect on both types of fruits but the high peak of infestation observed during September and October. It was calculated that 3 rd and 4 th larvae found a voracious feeder that gently hits dates fruit. The present investigation suggested that there is a vital need to introduce environment-friendly integrated pest management techniques and sufficient measures to secure this golden industry of this region.