大猿叶虫夏滞育的诱导：基于定量的光周期反应

为了探明大猿叶虫Colaphellus bowringi Baly夏滞育诱导的光周期时间测量特性, 我们通过室内实验系统比较了该虫在25℃、 不同长光照条件下,夏滞育的发生以及诱导50%个体进入夏滞育所需求的光 暗循环数。结果表明：不同长光照诱导的夏滞育比率有显著差异, 其中15 h或16 h光照诱导的滞育比率最高, 短于或长于这两个光照其滞育率均明显下降。在不同光 暗循环实验中, 14 h诱导的滞育比率均低于50%, 诱导50%个体进入夏滞育所需求的光 暗循环数在L15∶D9, L16∶D8, L17∶ D7和L18∶D6分别为2.61, 3.72, 4.64和5.92 d, 处理间存在显著差异。这些结果提示该虫夏滞育的诱导是基于定量的光周期反应。     

Immunohistochemical Analysis of IAA in Anthers of the Photoperiod-sensitive Genic Male-sterile Rice

The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) after long-day and short-day treatments. The distribution of free-IAA in anthers and its dynamic variation could be reflected by this method. The results showed that the IAA level in the anthers of Nongken 58S after long-day treatment was much lower than that in short-day-treated Nongken 58S and those in wild type Nongken 58 in five stages from pistil and stamen primordia formation to late uninucleate stage. The possible reasons for IAA deficiency in Nongken 58S-LD anthers and its relationship with fertility alteration were also discussed.     

中红侧沟茧蜂滞育临界光周期和敏感光照虫态的测定

室内对中红侧沟茧蜂Microplitis mediator滞育诱导的光周期反应及敏感光照虫态进行了研究。结果表明：在16℃和18℃温度下,当光周期为10L∶14D时,中红侧沟茧蜂的滞育率最高为98%和87.8%;其次是光周期为8L∶16D时,滞育率为78.7%和73%;光周期为12L∶12D时,滞育率为55.8%和50.8%;而在全光照LL, 光周期22L∶2D,20L∶4D,18L∶6D,16L∶8D,14L∶10D ,2L∶22D和全黑暗DD时的滞育率均为0。中红侧沟茧蜂属于典型的长日照发育型,在16℃时诱导滞育的临界光周期是7.03L∶16.97D和12.21L∶11.79D;在18℃时是6.75L∶17.25D和12.03L∶11.97D。16℃时中红侧沟茧蜂对光照反应最敏感时期为2龄幼虫第5～8天,2龄幼虫第1～4,9～12和13～16天及3龄期次之,卵期和1龄幼虫不敏感。     

Historical and projected interactions between climate change and insect voltinism in a multivoltine species

Climate change can cause major changes to the dynamics of individual species and to those communities in which they interact. One effect of increasing temperatures is on insect voltinism, with the logical assumption that increases in surface temperatures would permit multivoltine species to increase the number of generations per year. Though insect development is primarily driven by temperature, most multivoltine insect species rely on photoperiodic cues, which do not change from year‐to‐year or in response to climate warming, to initiate diapause. Thus, the relationship between climate change and voltinism could be complex. We use a phenology model for grape berry moth, Paralobesia viteana (Clemens), which incorporates temperature‐dependent development and diapause termination, and photoperiod‐dependent diapause induction, to explore historical patterns in year‐to‐year voltinism fluctuations. We then extend this model to predict voltinism under varying scenarios of climate change to show the importance of both the quality and quantity of accumulated heat units. We also illustrate that increases in mean surface temperatures > 2 °C can have dramatic effects on insect voltinism by causing a shift in the ovipositional period that currently is subject to diapause‐inducing photoperiods.     

光周期和温度对枯叶蛱蝶幼虫生长发育的影响

在人工气候箱中研究不同光周期和温度条件下枯叶蛱蝶Kallima inachus Doubleday幼虫的生长发育情况。结果表明,20℃时,光周期对枯叶蛱蝶幼虫发育历期影响明显,25℃和30℃时无明显影响。20,25和30℃,12.5~14h光照下,幼虫发育历期分别为31.7~36.0,26.3~27.4和21.0~21.5d,最长和最短历期分别相差4.3,1.1和0.5d。随着温度升高,在相同光照下,幼虫发育历期缩短。20,25和30℃12.5~14h光照下幼虫存活率分别为80%~92%、75%~95%和55%~85%,随温度上升,不同光周期下幼虫存活率差异加大。30℃时大部分光周期下存活率较低,已对幼虫生长发育不利,人工养殖时温度不宜超过30℃。     

光周期对菊花花芽分化及其叶片和芽内源多胺含量的影响

以切花菊品种神马为材料,研究不同光周期(16h昼/8h夜;12h昼/12h夜;8h昼/16h夜)对菊花花芽分化过程中叶片和芽内腐胺(Put)、亚精胺(Spd)和精胺(Spm)含量的影响.结果显示:(1)16h/8h处理植株始终没有花芽分化,8h/16h处理的花芽分化开始和完成分别在处理后第13.9天和第23.1天出现,比12h/12h处理的分别提前1.7d和2.8d.(2)16h/8h处理叶片和芽中Put、Spd和Spm含量始终都没有明显变化,而8h/16h和12h/12h处理的叶片和芽中Put、Spd、Spm含量都比16h/8h处理的明显增加,而且8h/16h和12h/12h处理的叶片Put和Spd含量在处理第10天和第20天时出现2个高峰,芽中Put和Spd含量在处理第15天时出现一个高峰;另外,8h/16h处理的叶片和芽中Put、Spd含量比12h/12h处理的有所增加,但差异不显著.结果表明,菊花神马是质型短日照植物,短日照可诱导神马叶片和芽内合成多胺,而且日照时数越短,越有利于叶片和芽内Put、Spd、Spm的积累和促进花芽分化.     

矮牵牛(Petunia hybrida)开花过程中的可溶性蛋白质分析

在进行矮牵牛(Petunia hybrida)光周期诱导开花的过程中,对叶子中的可溶性蛋白质进行了分析,其中有4条与开花有关的特异蛋白,分子量分别为49.45 kD(a)、35.45 kD(b)、17.98 kD(c)和11.74 kD(d).在不开放的花苞中不含有蛋白质a和d,只有这4种蛋白质全出现时,才能形成花苞并且开放.花开了以后,蛋白质c和d就消失.即使在开花的植株中,各组织中的蛋白质也是不同的.茎中完全不含有蛋白质c和d,叶子和花中的蛋白质组成也是不同的.     

Dark pretreatment improves adventitious shoot organogenesis from cotyledons of diploid watermelon

The influence of light incubation during embryo germination on shoot organogenesis from cotyledons of four diploid watermelon [Citrullus lanatus (Thumb.) Matsum. & Nakai cultivars was examined. Germinating embryos in darkness significantly improved the number of explants that produced harvestable shoots during the 6 week incubation period on shoot regeneration medium under a 16-h photoperiod. The percentage of explants with shoots more than doubled for `Crimson Sweet' and was about 1.5-fold greater for `Sweet Gem' and `Yellow Doll' when embryos were germinated in darkness. The percentage of explants with shoots was not significantly improved for `Minilee' by pretreating seedlings in darkness. This study demonstrates that optimal shoot regeneration can be obtained by germinating embryos in darkness before preparing cotyledon explants. This revised version was published online in June 2006 with corrections to the Cover Date.     

The effect of temperature on the photoperiodic 'counters' for female morph and sex determination in two clones of the black bean aphid, Aphis fabae

Experiments were performed on two clones of the black bean aphid, Aphis fabae Scopoli – one from Aberdeen, Scotland (57°N), the other from Cambridge, England (52°N) ? to determine the number of long- or short-night cycles required for 50% induction of winged versus wingless females on the one hand and males versus females on the other (i.e. required day number, RDN), at three temperatures, 12.5, 15 and 17.5°C. In the case of female morph determination, the RDN for long-night cycles was temperature compensated, whereas that for short-night cycles was highly temperature dependent. For sex determination, the RDN for long-night cycles was again temperature compensated, whereas, due to the mechanism of sex determination, male production was close to 100% in our protocol, even with a maximal number of short-night cycles, and the RDN could therefore not be assessed. Model-generated response curves, using the recently developed ‘double circadian oscillator model’ for photoperiodic time measurement in insects and mites, closely resembled the observations. It could also be shown that differences observed between response curves of female morph and sex determination in the Scottish clone were due, according to the model, to differences in their photoperiodic ‘counters’, rather than to differences in their clocks.