Growth inhibitor effects of bermuda grass, Cynodon dactylon (L.) on Schistocerca gregaria (Forsk.) (Orthoptra: Acrididae) [electronic resource].

Includes reference.

During the last plague of the desert locust, Schistocerca gregaria in the winter season of 2004 - 200S to Egypt, it was observed that Bermuda grass, CYlJodon dactylolJ (L.) argued to resist the infestations of this insect. To explore this observation, the present study was carried out in the laboratory in Locust and Grasshoppers Research Department, Plant Protection Res. Institute, Agriculture Res. Center, Ministry of Agriculture, Dokki, Giza, Egypt by feeding the 4th and 5th instar nymphs, Sclzistocerca gregaria on treated maize leaves with different extracts from leaves and roots of Bermuda grass in the solvents, methanol, acetone and etheoxyethanol. Results revealed that growth rate and metamorphosis of the treated nymphs were inhibited. Feeding of the 4th instar nymphs on the treated leaves of maize by methanol leaves extracted from grass leaves resulted in 8.3% mortality and 91.7% malformation of Sth instar nymphs which died after ecdysis. Also, treatment with methanol grass leaves extracts induced 40% mortality in the treated 4th instar nymphs, while the other 60.0% were molted to weak and small Sth instar nymphs. Feeding of Sth instar nymphs on the treated leaves of maize with methanol, acetone and ethoxyethanol leaves and roots of Bermuda grass resulted in different percentages of mortality ranged from 11.1% to 90.0%. the high mortality percent was obtained by ethoxyethanol leaves extract (90.0%). The lower one resulted after feeding on methanol leaves extract which induced the higher percent of adultoid insect (86.7%) followed by methanol and acetone root extracts (60.0%). The adultoid insects have had the intermediate features of the 5th instar and the adult stage.

Summary in Arabic.

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