ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 77 Number 2
Yield losses caused by blister beetle, Mylabris sp. (Coleoptera:Meloidae) in pigeon pea and its economic injury level in cowpea. (133)
In experiments conducted at the National Pulses Research Centre (Tamil Nadu Agricultural University), Vamban, yield losses caused by Mylabris sp. in two short-duration pigeon pea cultivars (Vamban 1 and ICPL86012) at three beetle densities (50, 100, and 150 per 50 plants) were assessed under caged conditions in the field. In Vamban 1, the reduction in pod numbers was 27.9, 69.0, and 91.7%, respectively, at the above beetle densities. The corresponding seed reduction levels were 18.7, 70.6, and 91.5%, respectively. Similarly, in ICPL86012, the pod numbers were reduced to 38.8, 54.5, and 85.1%, while the seed numbers were reduced to 47.7, 65.2, and 90.4%. The grain yield losses at the above three beetle densities were 21.5, 51.0, and 81.0%. In cowpea, grain yield loss caused by M. pustulatus Thunb. was assessed by introducing 2, 4, 6, 8, and 10 beetles per plant at flowering and assessing grain yields. Yield losses were positively correlated with beetle numbers (r = 0.87). An Economic Injury Level (EIL) of 3 beetles per 10 plants was established at flowering.
Keywords: Pigeon pea; Blister beetle; Yield loss; Cowpea; Economic Injury Level