A novel method for conserving cowpea germplasm and breeding stocks using solar disinfestation

Abstract

Experiments conducted in Maroua, Cameroon, demonstrated that a large 50-kg-capacity solar heater can be used to successfully eradicate infestations of Callosobruchus maculatus from cowpea seeds kept in small, transparent Minigrip ® ziplock plastic bags. Differences in temperature were noted in ziplock bags from different locations within the solar heater, but these were slight and not significant. Temperatures produced inside the heater were sufficient to kill all developing insects living within infested cowpea seeds. Small, transparent ziplock plastic bags are useful seed storage containers for short-term cowpea germplasm collections and are easily inspected during storage following solar disinfestation. Published reports indicate that temperatures of up to 85 °C do not adversely affect seed germination, germination rates, or seedling viability. These temperature and biological experiments provide evidence that the solar heater technique can serve as an effective and practical means to improve the short-term storage of cowpea seeds in developing country national agricultural research programs