Biological and Histological Effects of Metarhiziumanisopliae on the Cotton Leafworm, Spodoptera Littoralis (Boisd.) (Lepidoptera: Noctuidae)

Abstract

oxicological, biological and histological effects of the isolated entomopathogenic fungus Metarhizium anisopliae from the red palm weevil adult on the newly molted 2 nd and 4 th instar larvae of the Egyptian cotton leaf worm, Spodoptera littoralis (Boisd.), were investigated under laboratory conditions at 27º ± 2º and 60% ± 5% R.H. Results revealed a decrease in the mean larval, pupal, and adult durations for the 2 nd and 4 th instar larvae surviving treatment with the LC 50 of 2.8x10 8 and 2.8x10 9 spore/ml for the two tested instar larvae, respectively. Treatment also caused a reduction in the pupation and adult emergence percentage. There was also a great reduction in the mean number of eggs/female and the mean number of hatched eggs; The histological changes in the mid gut tissues in 6 th instar surviving treatment with LC 50 of M. anisopliae as newly ecdysed 3 rd instar larvae was investigated. Sections in mid gut of untreated S. littoralis showed linning with columnar cells surrounded by cross longitudinal muscles fiber, the epithelial cells linning mid gut with its brush border and goblet cells. While, in mid gut of treated S. littoralis some epithelial cells which linning mid gut have lost their brush border, others were completely destructed.

Effects Different Biomaterials on Biological and Histopathological Aspects of Cotton Leafworm, Spodoptera littoralis (Boisd)

“…While in figures (3 & 4) we found that within the midgut lumen, there is a thin membrane surrounding food mass, a musculosa surrounds the epithelial layer, composed an inner and out layer of longitudinal muscle. His with agree Lofty, Dalia et al, (2016) which reported that midgut containing different cell (i) A majority of columnar cells, (ii) Goblet cells are seen between columnar cells. (iii) Regenerative cells are small in size and are round or elongated.…”