Difficulties with cross-pollinating five cowpea lines: technique development

Abstract

Five lines of cowpea, Vigna unguiculata (L.) Walp., selected for evaluation in a forage trial, proved difficult to cross-pollinate. Pot trials were executed in glasshouses at controlled temperatures and relative humidities. A pot trial was also done outside the glasshouses under field conditions. Six different pollen transfer techniques were tested under high relative humidity condition. Results showed that high relative humidity benefits pod production following cross-pollination using technique 1. Technique 6, using a small soft paint brush for pollen transfer at sunrise, proved the most successful. Controlled glasshouse conditions were more beneficial to successful cross-pollination than the variable field conditions.