Larviposition by the Tachinid fly, Sturmiopsis inferens Tns. on sugarcane shoot borer larvae was studied. One adult female laid on an average 285 maggots (range 126-521). More than 90% of the maggots extruded were free of the enveloping chorion. Less than 4% were found to be unfertilized and undeveloped. The mean number of maggots laid per host was 1.21 and more than 70% were laid at the bore hole, the remaining being larviposited near the bore hole. Larviposition began on the sixth day after emergence of the female and mating, reached its peak during seventh to eleventh days and declined thereafter. Over 90% of the total number of maggots were deposited by the thirteenth day. Some maggots (9.52%) were not extruded but remained in the fly's uterus. The number of maggots laid at a bore hole varied from one to nine, but in more than 50% of the shoots only a single maggot was deposited. The flies preferred third, fourth and fifth instar larvae and shoots having only wet frass for larviposition, although larviposition did occur in shoots having second instar larvae and freshly formed pupae.

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Seven species of moth borers are known to cause heavy losses in sugarcane production in different parts of the country. Because of their concealed habits, the control of these borers becomes complex and hence a number of methods have been tried to suppress their field population. The sell behaviour of four species of these borers viz., internode borer, stalk borer, shoot borer and top borer have been studied in recent years and among these the internode borer and stalk borer have been found to have potent sex attractants.Mass trapping may be useful in the management of internode borer while disruption technique is likely to be useful in the case of stalk borer. In both the borer species, the synthetic pheromones will be highly useful in monitoring their activity.

Four pheromonal components have been detected in ovipositor washings and volatiles from female sugarcane stalk borers,Chilo auricilius Dudgeon (Lepidoptera: Pyralidae), using combined gas chromatography-electroantennography. The components have been identified as (I) (Z)-7-do-decenyl acetate, (II) (Z)-8-tridecenyl acetate, (III) (Z)-9-tetradecenyl acetate, and (IV) (Z)-10-pentadecenyl acetate by comparison of their gas chromatographic behavior with that of synthetic standards. In field tests carried out in northern India during 1982-1984, a combination of II, III, and IV in their naturally occurring ratio (8∶4∶1) was shown to provide a highly attractive synthetic source for trap use. (Z)-7-Dodecenyl acetate was found to reduce catches of maleC. auricilius, both when dispensed with the other three components and when released from dispensers surrounding a trap baited with the other three components.

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