Effect of sub-lethal concentrations of lufenuron on growth, development and reproductive performance of tribolium castaneum (herbst) (coleoptera: tenebrionidae).

The effect of the chitin synthesis inhibitor lufenuron on the various developmental stages of red flour beetle Tribolium castaneum was determined by exposing them to different sub-lethal concentrations (LC10, LC20 and LC40) of lufenuron through diet for 24 hrs. There was a dose dependent effect on the larval weight, time taken for pupation, and adult emergence, percentage pupation and percentage adult emergence. When two day old larvae were fed on sublethal concentrations through diet a small proportion of pupal –adult intermediates were observed at LC20 and LC40. Adults emerging from the larvae fed on diet containing LC10, LC20 and LC40 of lufenuron did not show any variation in the fecundity and hatchability of eggs from that of control. The fecundity of adults fed with sub-lethal concentration of lufenuron (obtained against two day old larvae through diet) was not affected, however, percentage hatching and survival was affected. Interestingly there was a reversal of the effect within ten days of treatment with respect to percentage hatching and survival. When eggs were exposed to treated diet hatching was not affected. The present data suggest that lufenuron even at sub-lethal concentrations has a very good larvicidal and ovicidal activity in T. castaneum.

Role of hysterectomy and its alternatives in benign uterine diseases.

There is a rising trend of hysterectomy rate as too frequently it is being performed now for conditions like symptomatic fibroids and dysfunctional uterine bleeding which can be treated alternatively. Hysterectomy, as with all other major surgeries, is also associated with increased mortality and morbidity risks. Various medical and surgical lines of management, other than hysterectomy, are presently accessible for the above conditions. Availability of safer and newer treatment options is great boon for women with changing attitudes towards child-bearing and uterine conservation.

Performance of Spodoptera litura Fabricius on different host plants: influence of nitrogen and total phenolics of plants and mid-gut esterase activity of the insect.

Five host plants [castor, Ricinus communis (Carolus Linnaeus); cotton, Gossypium hirsutm (Carolus Linnaeus); tomato, Lycopersicum esculentum (Philip Miller); mint, Mentha arvensis (Carolus Linnaeus) and cabbage, Brassica oleracea (Carolus Linnaeus)] belonging to different families were used to study the performance of the Asian armyworm, Spodoptera litura larvae. Highest consumption of food and dry weight gain was observed in larvae fed on castor. Mint did not support optimum larval growth because of low digestibility and low efficiency of conversion of digested food to body matter. Dry weight gain ranged from 26.64 mg on mint to 86.80 mg in castor. These differences tend to be related to nitrogen and total phenolics content of the leaf tissues; however, the most clear-cut correlation is an inverse one between the host plant preference and the ratio of total phenolics to nitrogen in the leaf tissues. Mid-gut esterase activity in larvae showed an increasing trend with the increase in total phenolics: nitrogen ratio in the test plants and the order of mid-gut esterase activity in larvae was mint > cabbage > cotton > tomato > castor.

An apparatus for the experimental demonstration of behavioural responses of the cyclopoid copepod, Mesocyclops leuckarti sensu lato to light and temperature.

To demonstrate the behavioural responses of Mesocyclops leuckarti sensu lato to light and temperature, an apparatus was designed and fabricated. It was found that light did not effect the orientational response significantly (p > 0.05) compared to the control. However, temperature gradient definitely influenced the orientational response (p < 0.05). The suitability of this apparatus for studying the behavioural response of other aquatic organisms are also discussed.

Effect of azadirachtin on Mesocyclops leuckarti sensu lato, vector of dracunculiasis.

Extension or otherwise of characteristic insect development inhibitory effects of the neem sesquiterpenoid azadirachtin have been examined on eggs and nauplii of the crustacean cyclops, M. leuckarti sensu lato, a major vector of guineaworm disease at 0.1 ppm and above doses. Azadirachtin reduced survival of early nauplii (N1 to N3) at 0.1 ppm and above doses. No such effect was observed when eggs and late nauplii (N4 to N5) were exposed. Azadirachtin did not affect the moult cycle when late nauplii (N4 to N5) were exposed continuously till adulthood. At all concentrations tested, adult cyclops exhibited normal mating.