黑杨萎蔫枝叶对棉铃虫生殖行为的影响

研究了黑杨(Populus nigra)萎蔫枝叶及其气味对棉铃虫成虫的隐藏部位、产卵部位、交配率及产卵量等的影响，并对黑杨萎蔫枝把在田间诱集到的棉铃虫雌蛾进行了解剖观察。结果表明，在田间，黑杨萎蔫枝把诱集到的棉铃虫93．3％已经交配。在气候箱中，放置黑杨萎蔫枝叶的环境中配对饲养的棉铃虫，经过1个暗期和2个暗期后，其交配率与对照环境中的均无显著差异。在光期开始时，有51．5％的成虫隐藏在饲养笼内所设置的黑杨叶子圆片下，对照纱布圆片下仅有16．7％。叶子圆片所在区域的日平均落卵量显著大于对照区。黑杨萎蔫枝叶及其气味对棉铃虫的产卵前期、产卵持续期、成虫寿命和产下50％的卵所用的时间无显著影响，但饲养笼内有黑杨枝把或黑杨叶片气味存在时，棉铃虫的产卵量比模拟枝把和对照显著提高。     

水杨酸和乙烯在烟草抗黑胫病中的作用

5mmol/L水杨酸或1g/L乙烯外源处理可诱导烟草对黑胫病的抗性，推迟植株死亡。不能积累水杨酸的转nahG基因植株和不表现乙烯应答反应的转etr1-1基因植株对黑胫病的抗性显著弱于野生型植株。组成性积累高水平水杨酸的转entC和pmsB基因植株对黑胫病的抗性明显强于野生型植株。这些结果说明水杨酸和乙烯增强烟草对黑胫病的抗性，减缓黑胫病的扩展。0．5mmol/L KCN连续浇灌植株4天或浸溃叶片2，4h均不能恢复转nahG基因植株丧失的对黑胫病的抗病性。此结果进一步支持关于KCN处理不能恢复转nahG基因植株丧失的对真菌病害抗病性的假说。     

大豆疫病的种子处理技术研究

本试验用不同浓度的瑞毒锰锌、杀毒矾和克露进行大豆种子处理试验，结果表明，５００ｐｐｍ瑞毒锰锌对大豆疫病具有很好的治疗作用，而用杀毒矾以种子重量０．４—０．５％的剂量闷种，能显著地抑制大豆疫霉菌的侵入     

温度对稻茎毛眼水蝇实验种群增长的影响

试验结果表明:在17～31℃恒温范围内,稻茎毛眼水蝇的发育速率随温度上升呈逻辑斯蒂曲线趋势。幼虫、蛹存活率、成虫产卵量、种群增长指数随温度的上升呈抛物线趋势。卵孵化率在20～31℃范围内无显著差异,均在92％以上。在17℃和35℃时,孵化率下降至86.67％和76.36％。在35℃时,幼虫不能存活,成虫不产卵。     

淡紫拟青霉发酵滤液对大豆胞囊线虫趋化性的影响

 实验室条件下,研究了大豆胞囊线虫幼虫对大豆根和根浸出液的趋化性以及淡紫拟青霉代谢产物对其趋化性的影响。结果表明,大豆胞囊线虫二龄幼虫(J₂)对大豆根存在着一定的趋化性,而淡紫拟青霉发酵滤液对J₂存在明显的驱避性。在根浸出液、真菌滤液及其混合液剂处理下,大豆胞囊线虫J₂在WA平板上靠近处理液的0~1cm区间中分布率存在极显著差异(P <0.0 1),而加样时间(液剂与线虫同时放置或提前2 4h处理)对其分布率没有显著影响。大豆幼根蘸取滤液后对线虫J₂在该区间的分布与不经处理的幼根差异显著(P <0.0 5),证明淡紫拟青霉发酵滤液可以明显地降低线虫与大豆根的亲和力,并强烈抑制线虫对大豆根的侵染。     

覆膜对宁南山区马铃薯光合特性和产量的影响

以青薯9号原种为材料，采用大田单因素随机区组设计，以不覆膜为对照，研究了覆盖黑膜和白膜对马铃薯光合特性、荧光参数、干物质积累以及产量的影响。结果表明：与不覆膜相比，覆膜条件下马铃薯净光合速率提高0.4~3.0个百分点，气孔导度和胞间CO₂浓度平均增加31.45%和6.58%，Fv/Fm、Fv/Fo、PI分别提高了2.47%、12.18%、20.93%；蒸腾速率在马铃薯生育前期覆膜比不覆膜降低20.82%，而后期却比对照增加8.55%，热耗散量子比率Fo/Fm覆膜较不覆膜处理降低7.11%，差异达显著水平；覆膜比不覆膜处理条件下马铃薯干物质积累量增加0.25~1.86个百分点，大薯率和中薯率分别增加33.78%，15.73%，每公顷产量增加43.08%，其中黑膜处理的各项指标优于白膜，黑膜比白膜和不覆膜增产16.86%、54.20%，差异达显著水平。因此，覆膜处理可以显著提高马铃薯的光合性能、荧光参数和产量，有效缓解干旱等逆境引起的马铃薯的衰老，减轻干旱对马铃薯的危害。在宁南山区，马铃薯采用黑色地膜覆盖栽培技术具有延缓叶片衰老和增加产量的作用。     

Soybean plant height QTL mapping and meta‐analysis for mining candidate genes

Plant height is closely related to seed yield of soybean. The goal of this study was to identify important loci affecting soybean plant height using meta‐analysis based on a reference physical map. Plant height related to QTLs was mapped across eight years with a RIL population by WinQTLCart v2.5. 182 QTLs related to plant height of soybean from database and our research were collected, and each QTL was projected onto the soybean physical map by software BioMercator v2.1. The confidence interval of meta‐QTL ranged from 0.09 to 5.07 Mb, and the mean phenotypic variance ranged from 4.9% to 73.0%. Furthermore, 4,259 candidate genes were located in these consensus QTLs, and 40 of them were involved in the plant growth and stem elongation and annotated as plant hormone signal transduction (pathway ID ko04075) in KEGG pathway. These results would lay a foundation for fine mapping of QTLs/genes related to plant height and marker‐assisted selection for breeding in soybean.     

Glycine max and Glycine soja are capable of cold acclimation

Soybean has been considered a cold intolerant species; based largely upon seed germination and soil emergent evaluations. This study reports a distinct acquisition of cold tolerance, in seedlings, following short acclimation periods. Diversity in cold responses was assessed in eight cultivars of Glycine max and six accessions of G. soja. All varieties of soybean significantly increased in freezing tolerance following acclimation. This study indicates soybean seedlings are indeed capable of sensing cold and acquiring cold tolerance. Germination rates after cold imbibition were negatively correlated with maturity group, but positively correlated with cold acclimation potential in G. soja. Seed fatty acid composition was varied between the species, with Glycine soja accessions containing about 2‐times more linolenic acid (18:3) than G. max. Furthermore, high levels of linoleic acid (18:2) in seeds were positively correlated with germination rates following cold imbibition in G. soja only. We suggest that domestication has not impacted the overall ability of soybean to cold acclimate at the seedling stage and that there is little variation within the domesticated species for ability to cold acclimate. Thus, this brief comparative study reduces the enthusiasm for the “wild” species as an additional source of genetic diversity for cold tolerance.     

野生大豆育成品种与其亲本间的遗传多样性比较

[目的]鉴定大豆育成品种与其亲本间的遗传多样性差异和遗传多态性信息含量,为大豆育种提供参考。[方法]采用SSR标记技术对大豆育成品种与其亲本间的遗传多样性进行分析。[结果]野生大豆亲本总等位变异数和特有等位变异数分别是栽培大豆亲本的1.31倍和3.63倍;平均多态性信息含量由大到小依次为野生大豆亲本(0.545 0)、育成大豆品种(0.478 7)、栽培大豆亲本(0.415 6)。[结论]野生大豆的遗传背景复杂,遗传多样性丰富,其外部形态和内在遗传基础都与栽培大豆有明显差异。