ABSTRACT
Periplaneta americana is an important medicinal insect. A series of new drugs developed from it have remarkable clinical effects and are in great demand in the market. Because of unclear biology, the quality and yield of P. americana are affected. Understanding the developmental threshold temperature and effective accumulated temperature of P. americana can provide theoretical basis for standardized culture of P.americana. Under climate chamber, the threshold temperature and effective accumulated temperature for egg development of P. americana to were determined through effective accumulated temperature law. The threshold temperature was （15.8±0.71）°C, the effective accumulated temperature was 415.8±38.05 degree days. A model of the relationship between temperature and developmental rates was established.
Subject(s)
Animals , Ovum , Physiology , Periplaneta , Physiology , TemperatureABSTRACT
Objective To determine the de ve lopmental zero and effective accumulated temperature of Oncomela nia eggs under con stant temperature. Methods The eggs were cultur ed under different constant temperature, and their development duration and effe ctive accumulated temperature were studied. The zero accumulated temperature (℃ ) was obtained by using an estimation mode, and the effective accumulated temp erature was obtained by effective accumulated mode of K=N(T-C). [WT5”H Z] Results The average development duration was (27.29?17 .2 9) d under 15-30 ℃, the development zero temperature was 11.79 ℃ and 38.22 ℃ u nder low and high temperature respectively, and the average development temperat ure and effective accumulated temperature were (557.76?198.95) DD and(236 .02 ?68.20) DD.Conclusion The suitable developme nt temperature of eggs is 27 ℃, the development speed and effective accumulated t e mperature of eggs increases with the temperature under given condition, but too high temperature may have negative impact on the development of eggs. The resul t can be considered as the basic biological parameter of the snail.
ABSTRACT
Objective To determine the effective accumulated temperature of Oncomelania hu-pensis during the period of development of generations in the natural environment. Methods The snails, Oncumelania hupensis, were raised in natural breeding site, the developing duration and accumulated temperature for .snails' development from eggs to adult that began to lay eggs were estimated based on the formula T=?(Ti-C). Results The average developing duration was (334.22?7. 52) days, average accumulated temperature was (5 821.38?70.05) day degree, and average effective accumulated temperature was (3 846.28?32. 59) day degree. Conclusion The method to estimate the effective accumulated temperature is quite accuracy, which provides theoretical parameters in developing the prediction model on transmission of schistosomiasis japonica affected by weather warming.