| The oriental fruit moth, Grapholita molesta Busck, a major pest in orchard of China, is widely distributed nationwide except Tibet area.The larva of G. molesta is small and can bore into twigs or fruits, with the feature of generation overlapping, about 2-7 generations per year. All the features result in the difficulty of forecasting and control. In recent years, with the increasing of fruit planted, the damage caused by G. molesta is aggravated year by year in many areas of our country, and causes devastating impacts on the commercial fruit production. Laboratory studies were designed to examine the effects of six kinds of nutriments for adults feeding and short-term heat treatment of 26℃, 29℃, 32℃, 35℃, 38℃on the longevity and reproduction of G. molesta. The main results are as follows.All of the six kinds of nutriments had obvious effects on the reproduction of G. molesta, and the 5% honey-water had the largest promotion effect on the reproduction of G. molesta. Compared with the distilled water, the pre-oviposition period of female feeding with nutriments was shorter and the oviposition period was longer. The female feeding with 5% honey-water solution had the shortest pre-oviposition period, and the one feeding with mixed liquids of sugar-aceticacid-ethanol had the longest period of oviposition. Compared with the distilled water, the female fed on nutriments had higher egg laying amount and hatching rate. The maximum egg laying amount and appeared in the treatment of adults feeding with 5% honey-water solution, reached 71.20/♀and 95.56% respectively, but egg laying amount was 24.27/♀and the hatching rate was 75.56% in the treatment of adults feeding with distilled water. Laying peak appeared earliest in the treatments of mixed liquids of sugar-aceticacid-ethanol and 5% brown sugar solution.The longest longevity of adults was the one fed on distilled water. The longevity of female and male was 16.7d and 13.07d respectively; while the shortest longevity of adults was the one fed on 5% brown sugar solution. The longevity of female and male was 9.98d and 8.10d respectively.There was a high mortality for adults at the treatment of 38℃for 48h. Under this condition the mortality of female and male was 91.67% and 95%. There was a significant influence on the pre-oviposition period of adults when the male suffering a short-term heat treatment, but not for female adults. With the increasing of temperature, the spawning period was shorter. The longest spawning period was 12 d at 26℃, the shortest spawning period was 6.67 d for male at 35℃.Short-term heat treatment had significant influence on the egg laying amount of G. molesta. With the rising of the processing temperature, the single female egg laying amount decreased. Single female egg laying amount was 74.83/♀under the condition of 26℃, which was significantly higher than others. The lowest single female egg laying amount was 2.58/♀when male suffering a Short-term heat treatment at 35℃. Under the same temperature, single female egg laying amount of female suffering heat shock was higher than male.Short-term heat treatment had significant influence on egg hatching rate of G. molesta. The egg hatching rate decreased as the rise of temperature. Under the condition of 26℃, egg hatching rate was highest, which reached 98.89%; Egg hatching rate was zero when male suffering a short-term heat treatment at 35℃. Except 35℃, under the same temperature, eggs hatching rate had no significant difference between male and female, but eggs hatch rates of high-temperature female processing was more than 10% higher than male processing.Spawning peak of G. molesta appeared from 5d to 14 d after eclosion. The earliest spawning peak appeared at 7th day after eclosion at 26℃. The emergence of spawning peak delayed, the peak of egg laying amount per day and the longevity of adults decreased as the rise of temperature. Adults had the longest longevity at 26℃, which reached 14.64d for female and 14.35d for male. Adults had the shortest longevity at 35℃, which reached 10.14d for female and 9.87d for male.
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