早籼稻重组自交系群体休眠性的遗传模型分析

利用弱休眠水稻品系‘996’和强休眠性品系‘4628’杂交,构建包含286个株系的重组自交系(recombinant inbred lines,RIL)群体,连续2年(2011、2012年)以当年收获的该群体种子的发芽率为指标,进行种子休眠性检测,并采用主基因+多基因混合遗传模型对早籼稻休眠性进行遗传分析。结果表明,在2011年试验中,‘996’ב4628’的重组自交系群体休眠性符合4对主基因(其中3对基因加性效应相等)–多基因加性上位性模型;在2012年试验中符合4对主基因(其中2对基因加性效应相等)–多基因加性上位性模型。2年试验结果均表明,该群体种子休眠性遗传符合4对主基因+多基因遗传模式,并且以主基因遗传为主。     

春用蚕种反季节饲养创夏秋蚕茧优质高产

根据嵊州市气候、环境条件实际 ,试行春种秋养 ,把握住操作技术 ,获得了优质高产的好成绩     

Induction of secondary dormancy in rape seeds (Brassica napus L.) by prolonged imbibition under conditions of water stress or oxygen deficiency in darkness

Prolonged imbibition under conditions of water stress or oxygen deficiency can lead to the induction of secondary dormancy in rape seeds. During imbibition in darkness seeds develop light sensitivity. The percentage of seeds not germinating in the dark depends on various factors prevailing during and after the stress treatment, as well as on the intrinsic susceptibility of the seeds to these factors.

In experiments on the effect of water stress it was found that the percentage of secondary dormant seeds could be increased in the range of 0–75%, by greater water suction and duration of imbibition of the seeds. Additionally, there were indications that increasing treatment temperature resulted in increasing percentages of dormant seeds. However, fewer secondary dormant seeds were produced when treatment temperature and test temperature differed greatly from each other.

Experiments on the effect of oxygen deficiency also revealed a positive effect of treatment duration. The general degree of dormancy induction, however, in this series of experiments was low. At 20 °C almost no dormancy induction was observed, whilst at 12 °C there were between 0 and 30% dormant seeds.

Genotypic differences previously assessed in model experiments with buried seeds were confirmed in both studies. Oilseed rape cultivars Bienvenu and Liglandor were shown to be able to build up high percentages of secondary dormant seeds, whereas cultivars Jet Neuf and Falcon had a rather low susceptibility towards the dormancy imposing factors tested. Cultivar Rubin was intermediate in response. There was often much variation between experiments with the same experimental design. The reasons for this are unclear.     

调亏灌溉对夏玉米光合生理特性的影响

在移动式防雨棚下，采用子母盆栽土培法和池栽微区试验相结合的方法，以夏玉米（Zeamay L．）为材料进行了调亏灌溉试验研究。结果表明，适时适度的水分调亏显著抑制蒸腾速率（Tr），而光合速率（Pn）下降不明显，复水后Pn又具有超补偿效应，光合产物具有超补偿积累，且有利于向籽粒运转与分配；抑制营养生长，促进生殖生长。玉米节水高产的调亏灌溉指标是：调亏时段为三叶-心-拔节（七叶一心），调亏度为45％FC（Field water capacity，FC）～65％FC，历时21d；或拔节一抽穗调亏，调亏度为60％FC～65％FC，历时21d；平均比对照增产25．24％，节水15．41％，水分利用效率提高45．05％。根据3因子正交旋转组合设计综合试验资料，分别建立了经济产量（Y）及水分利用效率（WUE）数学模型。     

温室有机土栽培越夏甜椒需水量的研究

研究比较了4个不同甜椒品种在温室越夏长季节有机土栽培下的水分需求,结果表明:植株生长势强的荷兰品种"卡地特"、"马里波"在较高灌水量下产量最高,而生长势较弱的国产品种"中椒12"、"甜杂7号"的需水量较低,中水量下产量最高。研究还发现夏季栽培条件下,灌水量较高的处理甜椒生长势强、单果重较大,国产品种采收早,前期产量较高。甜椒越夏栽培产量受高温影响有明显阶段性,高温期因座果率低而产量明显偏低,但温度适宜时产量明显回升。国外品种水利用效率略低于国产品种,这可归因于其植株高大蒸腾量也较大。据此可以认为在夏季高温需水量较大的情况下,温室甜椒需水量因品种、长势而异,国外植株高大、生长势强的品种需水量大于国产品种,较国产品种更具高产特性,适合温室长季节高产栽培。     

Case studies on breeding systems and its consequences for germplasm conservation

The first results of a study relative to the demography of wild Lima bean (Phaseolus lunatus L.) populations in the Central Valley of Costa Rica are presented. Six wild populations were selected in the four mainly representative ecological zones of this region and several 1 m₂ quadrats were demarcated in order to determine the vital rates (fecundity, survival, growth and mortality) of the individuals within each population. These data were collected during two years from 3000 labelled individuals and combined with those relative to the soil seed bank and the seed dormancy to propose a demographic model for a hypothetical mean wild population based on the projection matrix theory. This model helps to determine the growth rate of the population, the stability of its structure and, by using a sensitivity analysis, reveals also the factors most constraining for the population survival. Population behaviour under natural conditions and human pressure are simulated, which allow to propose management practices for in situ conservation.     

2008年夏玉米测土配方施肥田间示范

玉米是需肥较多的作物之一,多年来农民在玉米施肥上存在着很大的盲目性。由于不科学的施肥,施肥量过多,或偏施氮肥造成倒伏而减产,增加不必要的投入;反之施肥量过少,不能满足玉米生长的需要,也会造成减产。利用土壤养分测定的方法,根据土壤养分和玉米的需肥规律,进行科学配方施肥,起到了明显的增产目的。     

种子休眠与萌发分子机制研究进展

目的研究自然贮藏过程中‘莫拉特Ⅱ’杂交臂形草种子活力及抗氧化酶活性的变化规律,探明种子休眠的自然释放过程。方法以自然贮藏0~24个月的‘莫拉特Ⅱ’杂交臂形草的净种子为试验材料,每2个月取样1次,测定其发芽率、活力水平及抗氧化酶活性。结果在自然贮藏条件下,‘莫拉特Ⅱ’杂交臂形草种子的发芽率和活力水平随着贮藏时间的延长均呈现逐渐升高的趋势,贮藏24个月时,发芽率、发芽势、发芽指数和活力指数均达到最大值,分别为54.33%、53.00%、18.20和0.09,分别是对照(贮藏0个月)的1.70、2.27、4.92和7.46倍(P<0.05);过氧化物酶和超氧化物歧化酶的活性均呈现逐渐下降的趋势,而过氧化氢酶的活性则呈现逐渐升高的趋势。自然贮藏22个月,‘莫拉特Ⅱ’杂交臂形草种子的活力水平已有显著提高(P<0.05),发芽率达到了53.00%,是对照的1.66倍(P<0.05),与贮藏24个月没有显著差异(P>0.05)。结论结合“种子休眠通过标准”判定此时种子已经通过休眠,其休眠期为22个月。     

大棚保护地夏秋季利用的模式类型及其应用——以江苏省为例

针对大棚设施利用率低、夏秋季保护地空闲率高等普遍存在的问题,介绍了短季类蔬菜填闲利用、青鲜食作物接茬利用、攀缘型作物爬架利用、长季节栽培模式等4种大棚保护地夏秋季利用的模式,并以江苏省为例,分析了这4种模式的开发与应用现状,提出了一些相应的大棚保护地夏秋季利用配套技术。