Effect Of Food Plant On Development, Reproductive Performance, Survival And Nutritional Profile Of The Desert Locust, Schistocerca Gregaria Forskal (orthoptera: Acrididae)

Abstract

Protein insecurity in the 21st century is an emerging issue in most developing and under developed countries which has prompted search for alternative protein sources such as edible insects. The desert locusts, Schistocerca gregaria, Forskal (Orthoptera: acrididae) has been identified as a potential source of cheap protein and consequently mass rearing attempts are underway. The present study evaluated the effect of different food plants on the developmental, reproduction parameters and nutritional composition of S. gregaria with a view to mass production and enhancing its protein content. Nymphs and adults of S. gregaria were reared on Zea mays, Phaseoulus vulgaris, Sorghum bicolor and Triticum aestivum seedlings in the laboratory. Results revealed that development time of nymphs (first instar – young adult) was shortest (16.95 days) when reared on P. vulgaris and longest on Z. mays (45.06 days). Survival of nymphs to adulthood was highest when maintained on P. vulgaris (98.33%), followed by T. aestivum (93.33%) and S. bicolor (86.67%). No nymphs reared on Z. mays survived up to adult. Longevity and reproduction performance of S. gregaria was greater for insects reared on P. vulgaris, followed by T. aestivum as compared to S. bicolor. Nutritional profiling revealed significant differences in the crude protein content of S. gregaria reared on the different food plants at different adult phases. Ovipositing females raised on P. vulgaris contained the highest level of crude protein (86.10%) whereas the lowest was recorded in adults reared on S. bicolor (70.47%). These results suggest that S. gregaria is a nutrient rich food source for human and animal diets. Its life cycle and nutritional composition can be altered by the type of food plant fed on. P. vulgaris is therefore a suitable food plant for mass rearing S. gregaria and that this insect species is a good protein source.