Effect of X-ray irradiation on the F1 generation of Sitophilus zeamais Motschulsky and the germination rate of maize grain

Abstract

Abstract Background The use of X-ray irradiation in the control of the maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) infesting stored maize was tested at 60, 70 and 80 KeV as part of the international concerted efforts to save maize production and enhance food security. Investigations were done in the laboratory at mean temperature and relative humidity of 29.2 °C and 75.7%, respectively using three varieties of maize. The possibility that X-ray irradiation can affect the viability of maize grains when planted after weevil control process was also evaluated in the laboratory. Standard methods were used to achieve the specific objectives, and X-ray machine snap constituted the exposure time for each dose. Results The results revealed 10% mortality of adult weevils after 24 h and 40% mortality after a period of 7 days. The result indicates moderate effect on mortality. Progressive increase in mortality was recorded as dose increased from 60 to 80 KeV. X-ray irradiation at the doses tested did not significantly (P > 0.05) restrict S. zeamais emergence from maize grains and did not also significantly protect grains against damage and flour production. There was no difference in the pattern of daily emergence of new progenies and pattern of accumulated emergence. The relationship between X-ray irradiation doses and weight of emerging progenies require more specific analysis. Absence of significant difference between the viability of irradiated grains and un-irradiated grains strongly suggests that X-ray irradiation did not adversely affect seed viability, and this gives irradiation technique an opportunity of higher acceptability in agriculture. Conclusions We recommend > 80 KeV of X-ray irradiation or its incorporation into integrated pest management system in order to achieve effective post-harvest control of the pest.