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Abstract - 115 - SUM 1:.1A. R Y· The present study was conducted at Bahteem Agriculture Research Station in order to have better under- ,.•~” standing on the effect of intensive agriculture on the rate of infestation of different cotton insects. Four treatments ( hill spacing , row spacing t design during 1981, 1982 seasons. ” Giza-67” cotton variety was planted in an area of two feddan. divided into 4 equal parts. Each part representing an experimental unit. The following results were obtained, 1 - Aphids and Thrips: A- Hill spacingl- ~he tested treatment showed that in 15 em. hill spae;ng was severely attacked while the lowest damage was recorded in 35 cm. hill spacing .Analysis of variance showed highly significant dlfferance between the four treatment .” B- Row spacingl- Thr: maximum rate of infestation by Aphids and Thrips in 14 Tows/2Kassaba while 10 rows/2Ka. were less attacked .”Analysis of variance gaTe highly significant difference in the tested treatments • -- - ------- - ...116 - c- Planting on both sides of row Planting on bQ,th sides of row showed higher infestation than the control treatment but ”t” tested was insignificant between the two treatments • 2 - Cotton leafworm infestation z A - Hill spacing : Results showed that 15 em. treatment attracted the highest number of egg-masses while 35 em , hill spacing’ . gave the lowest number of egg-masses • Analysis of variance showed highly significant defferenee between the tested treatments • B - Row spacing : Results obtained showed that 14 row/ 2 kassaba harboured the highest number of egg-masses while 10 rows/ 2 kassaba harboured the lowest egg-masses Analysis of variance showed highly sign~icant difference between tested treatments • c - Planting on both side$of row: Planting en both sideS of row harboured’ high numbers of egg-masses that the control treatment tit” test showed that no significant differe~ce betwee~ exists the two treatments • ----~-- - -- --”---- - 117 - J - Pink and spiny bollworm infestation z The population cf pink bollworm was higher than the spiny bollwolm • The degree of spiny bollworm infestation of tested treatment was very low • It was no·i;icec. that it attacked the green bolla during the end of the season • Analysis of variance of the data obtained during 1981 and 1982 seaSOl~ showed that no signifioant differences between the number of pink. bollworm in the different tes’~ed treatments • It was noticed that the highest number of pink bollworm wes observed in 35 hill spacing and 10 row spaoing. Yield loss : ’j The yield loss percentages generally increased by the inorease of the distance separating the ootton hills or rows. The planting on both sides of row treatment gave the least yield loss. |