INFLUENCE OF RED GUM PLANT EXTRACT,
EUCALYPTUS CAMALDULENSIS, AND / OR GAMMA IRRADIATION ON THE NUTRITION
AND UTILIZATION OF THE FOOD
OF THE COTTON LEAF WORM SPODOPTERA
LITTORALIS (BOISD.)
*
HAZAA, M.A.M.
Biological Application Department, Nuclear
Research Center,
Atomic Energy Authority, Egypt.
Key words: Gamma radiation, Inherited
sterility, Spodoptera littoralis,
Plant extract, Food consumption, Eucalyptus camaldulensis.
تأثير مستخلص نبات الكافور و/أو اشعة جاما على التغذية ومدى
الاستفادة منها فى حشرة دودة ورق القطن
مجدية عبد الرحمن محمد هزاع
خلاصـــة
ABSTRACT
The effect of gamma radiation (75, 100 and 125 Gy) and/or leaf extract of the red gum, Eucalyptus camaldulensis (Family: Myrtaceae), on different food consumption aspects of the third and fourth instar larvae of F1 generation of Spodoptera littoralis was studied. The amount of consumed food was significantly reduced especially in 3rd instar while in fourth instar this decrement was non-significant. In spite of increment in the C.I, A.D, G.R and decrement of feces quantity, the food balance, mean weight and weight gain values were decreased as compare to control. Also, the combined effect of gamma irradiation and plant extract clearly decreased the utilization of food as indicated by determining both efficiency of conversion of ingested food (E.C.I) and digested food (E.C.D) to body matter than treatment of each of them alone. The consumption percentage followed the same manner while the antifeedant percentage was mostly increased in combined treatment in the two successive instars.
The effects of separated or combined treatments on different developmental aspects were also studied. Gamma irradiation and combined treatment delayed larval duration, reduced pupation, emergence and survival. On the other hand, the percentage of development per day, the indices of growth, survival and assimilation were obviously reduced.
