【作者】 陈艳艳；

【导师】 朱道弘；

【作者基本信息】 中南林业科技大学 ， 动物学， 2012， 硕士

【摘要】 为探讨中华稻蝗Oxya chinensis Thunberg一化性种群滞育卵适应策略的地理变异,以铁岭、济南、开封和信阳种群为材料,检测了其子代卵滞育的发生、滞育强度、发育起点温度、有效积温及发育起点以下低温对不同地理种群卵滞育解除的影响。主要结果归纳如下：(1)中华稻蝗四地理种群的滞育率均为100%。开封与信阳种群卵粒在25℃条件下观察期100d内未见有卵粒孵化,而铁岭与济南种群则分别61d和78d开始零星孵化,结果表明四地理种群均为完全滞育,但其滞育程度存在差异。(2)中华稻蝗一化性地理种群的卵滞育强度存在显著的地理变异,高纬度的铁岭种群滞育强度最弱,中间纬度的济南和开封种群较强,低纬度的信阳种群滞育强度最强,铁岭、济南、开封和信阳种群的滞育强度呈随纬度的降低而增强的趋势。(3)同一地理种群中华稻蝗发育历期随着温度的升高逐渐缩短,但四地理种群中华稻蝗的发育历期存在地理变异。以最小二乘法计算得出铁岭、济南、开封和信阳四地理种群发育起点温度分别为14.1士0.5℃,15.8±0.5℃,14.9±0.6℃和15.1士0.9℃。铁岭、济南、开封和信阳四地理种群的有效积温分别为179.1±8.6日·度、187.8士10.1日·度、197.7士10.2日·度和208.2士8.9日·度。结果表明,各地理种群的发育起点温度与有效积温随地理随纬度升高而降低。(4)发育起点温度以下、0℃以上低温能够明显促进四地理种群中华稻蝗卵滞育的解除,同一温度条件下,随着低温处理时间的延长,滞育解除效果愈加明显,但低温对四地理种群卵滞育的解除显现出明显的地理变异。高纬度的铁岭种群在各个温度处理孵化率显著高于较低纬度的济南、开封和信阳种群,低纬度的信阳种群在各个温度处理其孵化率均显著低于开封、济南和铁岭种群,随着处理时间的延长,各地理种群孵化率的差异逐渐变小。中华稻蝗铁岭种群滞育发育的适温范围为1-13℃,最适温度为10℃；济南和开封种群滞育发育的适温范围为4-13℃,最适温度为10℃；信阳种群滞育发育的适温范围为7-13℃,最适温度为13℃。(5)0℃以下低温处理能够明显促进中华稻蝗卵滞育的解除,但其促进效果在不同地理种群间存在明显的地理差异,0℃以下低温对低纬度的信阳、开封种群只能促进其零星孵化,但能明显促进铁岭种群孵化。对铁岭种群而言,不同的低温促进效果也存在明显差异,其中以-3℃的促进效果最为明显。更多还原

【Abstract】 To investigate the strategy of the overwintering egg in Oxya chinensis Thunberg, incidence of embryonic diapause, diapause intensity, threshold temperature, effective temperature and the influence of low temperature on diapause termination were compared among four univoltine populations collected from Tieling, Jinan, Kaifeng and Xinyang cities. The main results are as followed:(1) The percentages of diapause of four populations were100%when eggs incubated at25℃. A part of eggs of Tieling and Jinan populations were hatched, but no eggs of Kaifeng and Xinyang populations were hatched during an observation period of100days. The first hatching occured on day61and78for the Jinan and Tieling pupulations respecitively.(2) The intensity of egg diapause was lowest in the Tieling population with a highest latitude, followed by the Kaifeng and Jinan populations with intermediate latitude, and highest in Xinyang population with a lowest latitudes. The results indicated that diapause intensity increase with the decrease of latitude.(3) The development period of O. chinensis decreased with the increase of incubation temperature, but there was a geographical variation among these four populations. The developmental threshold temperature and effective accumulated temperature of the four populations were analyzed by the least square method. The developmental threshold temperature were14.1±0.5℃,15.8±0.5℃,14.9±0.6℃,15.1±0.9℃and the effective accumulated temperature were179.1±8.6,187.8±10.1,197.7±10.2,208.2±8.9day degree for Tieling, Jinan, Kaifeng and Xinyang populations respectively. The results indicated that the developmental threshold temperature and effective accumulated temperature increased with the decrease of latitude.(4) Low temperature between0℃and developmental threshold temperature had strong effect on diapause termination and the longer of the time of low-temperature treatment, the more obvious of its effect on diapause termination. Hatching rate was the highest in the Tieling population and the lowest in Xinyang population. The suitable temperature ranged from1℃to13℃for Tieling population,4℃to13℃ for Jinan and Kaifeng populations, and7℃to13℃for Xinyang population, and the optimum temperature for diapause development was10℃for Tieling population,10℃for Jinan and Kaifeng populations, and13℃for Xinyang population.(5) Low temperature under0℃showed obvious influence on diapause termination rate of these four populations, but the influence showed obvious geographical variation among them. Low temperature under0℃didn’t show obvious influence on the hatching rate of diapausing eggs in Jinan, Kaifeng and Xinyang populations, but the hatching rate of Tieling population could be obviously enhanced. The hatching rate of Tieling population was different when exposed to different temperature, and low temperature (-3℃) had the most strong effect on diapause termination.更多还原