大豆基因组GmRAV同源基因的生物信息学分析

利用Phytozome数据库、NCBI网站,和MEGA4.0、ClustalX软件对大豆(Glycine max)基因组中RAV同源基因进行了生物信息学分析,发现大豆RAV基因有4个拷贝,分别分布于第1、2、10和20号染色体上;RAV蛋白含有AP2/ERF (53～ 108)和B3( 172～ 286)结构域.豆科植...     

不同光周期条件下绿色型豌豆蚜性蚜分化规律研究

为了明确豌豆蚜随光周期变化时的种群繁殖策略以及性蚜分化规律,在4个光周期(8L∶16D、10L∶14D、12L∶12D和14L∶10D)条件下,研究了绿色型豌豆蚜经光周期连续诱导2代后(G_1和G_2),后代(G3)中的性蚜分化情况。结果表明:兰州地区豌豆蚜性雌蚜均为无翅型,而雄蚜均为有翅型。光周期对豌豆蚜性蚜分化有显著影响(P0.05)。在14L∶10D光周期条件下,豌豆蚜后代中无性蚜分化;在12L∶12D、10L∶14D和8L∶16D 3个光周期条件下均有性蚜分化,而且随着光照时间的变短,豌豆蚜G_3中雄蚜所占百分比逐渐减小,性雌蚜所占百分比逐渐升高。在12L∶12D光周期条件下,雄蚜比例最高(30.39%),而性雌蚜比例最低(55.67%);在10L∶14D光周期条件下,G_3中胎生蚜比例最高,而性蚜比例最低;在8L∶16D光周期条件下,无雄蚜分化,而性雌蚜比例最高(90.76%)。在同一短光照条件下,G_1产仔日龄对G_3中性蚜分化具有显著影响(P0.05),同时性蚜分化具有一定的时间顺序,即先产性雌蚜,后产雄蚜,由性雌蚜向雄蚜过渡过程中伴随产生胎生蚜。表明绿色型豌豆蚜性蚜产生的临界光照时长介于12~14 h,相对较长的光照条件下有利于雄蚜产生,而光照时间越短性雌蚜比例越高。说明光周期变化是豌豆蚜生殖模式转变和性蚜分化的重要因子,而且豌豆蚜亲代经历光周期处理时间的长短影响后代中性蚜的分化。     

水稻光周期敏感雄性不育性的遗传学研究——F#-2分离群体育性分布的多态性

笔者考察了光敏不育晚熟粳稻与北方早粳杂交F#-2群体的个体育性频率分布,共考察了可在北京自然长日照条件下抽穗的6个群体。直观方柱图可见均为偏态连续分布,双峰型：过渡型：单峰型=3∶1∶2。只有半数群体呈双峰分布型,而且它们的峰（或谷）值所在区间自交结实率小于10%（尤其是自交完全不结实）个体的频率亦不相同。当然,在其它分布类型的群体间这类个体的频率也不相同,而且数值更小。利用Kruskal-Wallis法,成对比较这些群体,尤其是自交结实率在0-40%区间的子群体,检验结果表明,来源于同母异父组合的群体分布是不同的。即使同为双峰或单峰型,其间也有显著的差异。考察F#-3世代株系群的结果证明,单峰分布型的群体象双峰型群体一样,分离出不育基因纯合体。据F#-3世代不育株系的数目可推测,这类F#-2个体约有4%。它们并不都集中在低值区间;有不少存在于自交结实率大于40%的中、高值区间。另一方面,双峰分布型群体中的低值个体只有约50%形成 F#-3不育株系。笔者推测,F#-2世代表现型值除取决于不育主基因型和环境条件外,还受亲本育性基因组成及状态的深刻影响。     

Interactions of photoperiod,temperature, duration of short-day treatment and plant age on flowering of Fragaria x ananassa Duch. cv. Korona

The effects of photoperiod (10, 12, 16, 20 or 24 h), day-temperature (12, 15, 18, 24 or 30 °C), the number of short days (14, 21 or 28 days), plant age (4, 8 or 12 weeks) and their interactions on flower and inflorescence emergence were investigated in strawberry cv. Korona. No flowers emerged in plants exposed to photoperiods of 16, 20 or 24 h or to a short-day treatment for 14 days. All plants exposed to short days at daily photoperiods of 10 or 12 h for 21 days or longer, emerged flowers at temperatures between 12 and 18 °C. A further increase in temperature led to a drastic decrease in the total number of flowers per plant. A short-day treatment (10 or 12 h photoperiod) of 28 days resulted in highest numbers of inflorescences and flowers per plant, while a short-day treatment of 21 days resulted in the highest numbers of flowers per inflorescence. Complete flower induction was observed in only 4-week-old runner plants. The number of inflorescences and the number of flowers per inflorescence increased with plant age. However, the start of flowering was delayed with increasing plant age.     

Reproductive responses of rabbit does to a supplemental lighting program

The objective was to investigate whether the productivity of rabbit does can be improved, when natural photoperiod is decreasing, by adopting a supplemental lighting program. Three experiments were conducted involving two groups: control, submitted to the natural decreasing photoperiod, and supplemented with a lighting program which provided 14 h light/24 h beginning at 10 weeks of age. In the first experiment, 20 nulliparous does, 10 from each group, were euthanized 8 h after being presented to a buck; the overall number of follicles, whose diameter exceeded 1 mm, was determined macroscopically. The right ovaries were collected, histologically analyzed, and electronically measured. In the second experiment, 30 nulliparous does, 15 from each group, were presented to a buck (day 1). Receptive does were euthanized on day 8 to evaluate embryonic survival (number of normal embryos/ovulation rate). In the third experiment, 48 nulliparous does, 24 from each group, were followed from the first presentation to the buck until the weaning of the first litter. The effect of treatment on reproductive and body weight traits of does, and litter performance traits, at birth and weaning, was evaluated. The average number of follicles whose diameter exceeded 1 mm was higher in the treatment group (12.05±1.07 vs. 8.63±1.00, P=0.037). Receptive does of the treatment group had heavier ovaries relative to those of the control group (790±59 vs. 470±64 mg, P=0.004), whereas no treatment difference regarding this trait was found for non-receptive ones. Treatment had a favorable effect on pregnancy rate of total exposed and of receptive does (80.0% vs. 33.3%, P=0.01, and 92.3% vs. 50.0%, P=0.02, respectively). The number of underdeveloped embryos was lower (0.067±0.380 vs. 2.500±0.455, P=0.004), embryonic survival up to day 8, and uterus weight was higher in the treatment group (0.839±0.075 vs. 0.534±0.087, P=0.033 and 13.83±0.72 vs. 10.99±0.84, P=0.037, respectively). Number of presentations tended to be lower (1.32±0.17 vs. 1.75±0.16, P=0.077) and adjusted litter size in the first reproductive cycle tended to be higher (7.09±0.89 vs. 5.22±0.68, P=0.091) in the treatment group relative to the control group. A supplemental lighting program providing 14 h light/24 h favors reproductive performance of primiparous does; its application may be recommended to increase productivity when natural photoperiod is decreasing.     

光周期与温度对苹果蠹蛾滞育解除的影响

[目的]探讨苹果蠹蛾滞育解除的机理及影响因子。[方法]研究不同的光周期与温度梯度对苹果蠹蛾滞育解除的影响。[结果]对于苹果蠹蛾滞育幼虫,在一定低温范围内,低温处理的温度越低,苹果蠹蛾滞育解除的效率就越高;长光照虽然能够促进苹果蠹蛾滞育的解除但不是其打破滞育的依赖因素,如果不经过低温处理,苹果蠹蛾很难解除滞育;在低温处理的基础上,光照时间越长,其化蛹率越高,越有利于苹果蠹蛾滞育的解除,低温与长光照的配合能有效地解除滞育。[结论]低温是解除滞育的关键因素。     

光照周期和饲喂水平对蛋鸡生殖器官发育的影响

本试验旨在研究限饲和光照周期对蛋鸡卵巢和输卵管发育及形态学的影响。试验采用3×2双因子设计,即3个光照周期（8L：16D、12L：12D和16L：8D）和2个饲喂水平（自由采食和限饲鸡自由采食量的80%）。选用体质健康的10周龄海兰灰蛋鸡240只,分成6组,每组4个重复,每个重复10只鸡。结果表明,光照周期显著影响20 w输卵管重（P〈0.05）,长光照周期（16L：8D）组和中长光照周期（12L：12D）组的20 w输卵管重显著高于短光照周期（8L：16D）组,对卵巢卵泡直径及单位面积内卵巢卵泡个数影响不显著（P〉0.05）;饲喂水平对20 w体重、卵巢重、输卵管重及卵巢卵泡直径和单位面积内卵巢卵泡个数影响均不显著（P〉0.05）;光照周期和饲喂水平互作对20 w卵巢卵泡直径影响显著（P〉0.05）,其中,β和VI组卵巢卵泡直径显著高于V组（P〈0.05）,其他各组间差异不显著（P〉0.05）。饲喂水平、光照周期影响输卵管发育,Ⅱ、Ⅳ、VI自由采食组发育程度优于Ⅰ、Ⅲ、V限饲组,并且16L：8D光照组输卵管的发育状况最好。     

曙暮光在光敏感核不育水稻两个光周期反应中的作用

 本文论证了曙暮光在光敏感核不育水稻两个光周期反应中均有明显的作用,初步探明农垦58S 在武汉地区(30°27′N)育性转换期(7—8月)曙暮光的变化规律,提出采用“光照长度”以代替“日照长度”来划分光周期的昼与夜更为准确的见解,据此讨论了曙暮光的作用对光敏感核不育水稻在不同地理条件下的生态适应性的重要影响。     

黑龙江省小麦品种穗发芽及光周期的分子检测

为了明确黑龙江省小麦品种的光周期特性及穗发芽抗性水平,利用Ppd-D1及Vp1B3标记对95个推广品种进行了检测。结果表明,有68个品种扩增出了与抗穗发芽相关的569 bp特异条带,占供试品种总数的71.6%;有27个品种扩增出与感穗发芽相关的652 bp特异条带,占供试品种总数的28.4%,说明在黑龙江省加强抗穗发芽品种选育十分必要。有70个品种(占总数的73.7%)扩增出了与光周期敏感性相关的414 bp特异带;有25个品种(占总数的26.3%)扩增出了与光周期不敏感相关的288 bp特异带,这些品种具有广泛的适应性。     

Physiology of flowering and grain filling in faba bean

The development of flowers and then that of seeds are key processes in the formation of yield in faba bean (Vicia faba L.), as in other grain legumes. Winter faba bean generally has a quantitative vernalization requirement, allowing flowering to occur at a lower node than in unvernalized plants. Some germplasm is day-neutral, other germplasm is long-day with a critical daylength between 9.5 and 12 h. Progress toward flowering follows a conventional thermal-time model, with 830–1000 °C-d above 0 °C required for the onset of flowering and an optimum temperature of 22–23 °C. Flowers may abscise from the crop because of lack of pollination, because proximal flowers on the same raceme are fertilized, because of vegetative–reproductive competition for assimilate, or because of stresses such as drought.