Effect of Megachile sp, an insect flower visitor on nutrient content of progenies of cowpea [Vigna anguiculata (L.) Walp].

Abstract: Though cowpea (Vigna unguiculata (L.)Walp) possess several nutritional values its mode of pollination is fraught with some forms of confusion. Attempt to ascertain the role of insect visitors on the plant led to collection of seeds from flowers visited by bee species known as Megachile (experimental plants) and flowers not visited by any organism (control plants). The seeds were re-sown to determine the influence of Megachile on nutrient contents of the seeds of the progenies. Nutrient analysis of the seeds from the progenies was done. Mean values were compared with paired t-test and Pearson correlation. Higher starch (carbohydrate) (362.6±0.40mg/Kg to 374.4±0.28 mg/Kg) values were recorded for progenies of control than the experimental plants (340.4±0.44mg/Kg to 352.9±0.27 mg/Kg). Differences between means were highly significant (t = 16.91; P < 0.00; df = 17). Mean calcium, phosphorus and protein values of seeds of the progenies of experimental plants were higher than that of the control plants. There was very strong positive correlation between protein and starch (r = 0.727; p < 0.01) for the progenies of control, but negative correlation between protein and starch (r = -0.476; P<.05) for experimental plants. In conclusion, visitation of Megachile to a cowpea flower may cause cross-pollination which may induce seeds of the progenies to develop higher calcium, phosphorus and protein values. It is recommended that cowpea farmers should adopt the best pest control measures in order to preserve useful insects to cause cross-pollination. Keywords: Megachile, fibre, cross-pollination, nutrient, calcium, cowpea.