الفهرس 
Physical factorsOnly 14 pages are availabe for public view
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Abstract
The purple lined borer, Chilo a&unemnon Bles. is one of the major i n s t c t pests t h a t i n f e s t r i c e , maize and sugar cane plmts in Egypt. Nany programs for controlling this pest require laboyat ory mass product ion during the whole year. Hence, the main object of the present study is t o detect the optimum conditions of some physical factors under laboratory conditions and t o obtain more informations about some of the bialogical aspects of the pest. The obtained results we!re s~mmardzed as follows: 1- Effsct of certain photopericds: a- -D- aring the egg-o: -- The incubat ion period gradually increased by decreasing the light period, The lowest percentage of larval mcrtality was obtained when eggs incubated a t contixu.o??~lsi g h t , vihile the highest percentage of larval mortality was rc2orded at 6 hr. of light or less. The longest larval pried . vtas obtained when eggs were incubated a t c.ont2r-r~.1ousi llumiraiion, while the shor tes t one wa s found at 12 : 12 L D hr, ’b- -D-.---.L?u rin. the l a r v-a-l stage: When the l a r v a l stage w a s expcaed t o continuous illumination, the lowest percentage of larval mcrtaliky was obtained, The average larval period was cbviouzXy pmlciiged by increasing the period of dark, while a full-day light caused acceleration for the larval growth.