| In this paper, we studied the relationship between temperature and growth development of Locusta migratoria manilensis (Meyen), also with the physiological parameter changes of locusts when they were infected by M. anisopliae. The results showed that the developmental duration shortened with the temperature increased, the hatching phase of eggs was 38.0d, 28.6d, 17.0d, 12.1d and 8.4d from 15℃to 35℃. There was a clear positive correlativity between temperature and the growth rate of L. m. manilensis which was the same instar. Also the growth rate increased linearly when the instar growed up at the same temperature.Also we analyzed the relationship between temperature and eating, efficiency of food conversion of L. m. manilensis by contrast weighing methods. The result showed that the accumulated developmental duration was 56.9d, 34.0d, 21.3d, 17.2, 15.0d and the total food consumption was 0.85g, 0.88g, 0.82mg, 0.99g, 0.99g respectively at 18, 21, 24, 27 and 30℃, from 3rd to 5th instar nymphs. The longevity of male adult was 90.3d, 62.8d, 47.0d, 38.7d, and total food consumption was 3.62g, 4.67g, 4.25g, 4.26g respectively at 21, 24, 27 and 30℃. The longevity of female adult was 95.8d, 63.0d, 46.3d and 40.8d, the total food consumption was 6.97g, 10.48g, 10.41g and 11.90g respectively at 21, 24, 27 and 30℃. With increasing of the temperature, the approximate digestibility reduced, and the efficiency of conversion of ingested food increased from 3rd to 5th instar nymphs. While the approximate digestibility at 18℃was higher than at 30℃, because the digested food was not only for body weight increasing, but also for drinking water. But the efficiency of conversion of ingested food was no significant difference at different temperatures in developmental stages of adult. According to the analyzing of the mating and ovipositing behavior of L. m. manilensis at 18,21,24,27 and 30℃, the results showed that temperature had significant influence on mating and ovipositing behavior. There was no mating behavior at 18℃and the mating rate was only 20% at 21℃, also there was no eggs laid by female adults. At the other hand, when temperature was no less than 24℃, the mating rate was 100% and the effective mating rate was 77.80%,122.09%,146.43. The pre-oviposition period of female adults was 14.6d, 13.1d and 12.7d at 24, 27, 30℃, but there was no significant difference.While the weight of each oocyst at 27 and 30℃was higher than 24℃.When the locusts were infected by M. anisopliae, the total food consumption of 3rd-5th nymphs was 96.4, 108.3, 131.9, 103.2 and 249.5mg at different temperatures; At 21, 24, 27 and 30℃, the total food consumption of male adults was 93.1, 121.8, 109.0 and 237.5mg, while for the female adults was 108.7,195.5,234.7,114.7mg. The approximate digestibility of nymphs was going down, while the conversion efficiency was going up with temperature increased, and the latter was a negative value at lower temperature. There were no significant differences for the approximate digestibility of male adults, but it decreased after arising for female adults at different temperatures. For the conversion efficiency of male adults, they were going down when temperature arose from 24 to 30℃, but not for female adults. Compared to CK, the infected locusts were much less than CK for the total food consumption. We studied the food consumption changes for the different developmental stage, it showed that the day food consumption of CK nymphs went up when nymphs grew up at the same temperature, and the female adults were higher than male adults; the total food consumption changes of the CK locusts as the same as the changes of the day food consumption. But there was no significant regularity for locusts when they were infected by M. anisopliae.Also we found that L. m. manilensis had thermoregulation ability for the locust. The body temperature changes of 3rd nymphs were 7.4, 5.6, 5.2, 3.8 and 3.5℃at different environmental temperatures which were 18, 21, 24, 27 and 30℃, which showed that the locust had higher thermoregulation ability at the same developmental stage when it was at lower temperature. But for different developmental stage, the changes of 3rd, 4th, 5th nymphs, male adults and female adults were 7.4, 6.8, 5.4, 2.1 and 1.6℃, when the environmental temperature was 18℃. It showed that the thermoregulation ability of young nymphs was more than old nymphs and adults. When it was infected by M. anisopliae, compared to CK nymphs, the infected locusts'thermoregulation ability was lower, but it was opposite for the adults, because the locust had the strongest ability when it was infected 24h later. For different developmental stage, when nymphs were at lower temperatures, as adults were at higher temperatures, who had higher thermoregulation ability.
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