黄淮旱地组小麦品种抗旱性鉴定比较分析

为了解近年来黄淮冬麦区旱地组小麦品种抗旱性的整体情况,对2017—2019年黄淮冬麦区132个区试品种（系）在干旱胁迫下的产量及抗旱指数,穗数、穗粒数、千粒重、株高等性状及抗旱系数,进行分析总结。结果表明：黄淮旱肥组、旱薄组、北部组区试品种（系）近年来品种的抗旱性趋势大体相同,胁迫情况下产量总的变化是旱肥组>旱薄组>北部组,且呈逐年稳中有升的趋势,从抗旱指数看,黄淮旱地小麦品种的抗旱整体还处于偏弱的水平;抗旱性状表现为干旱胁迫下均有不同程度的受损,均以千粒重的受损程度最小,有效穗、穗粒数、株高受损程度最大。     

花粉管通道法转化荔枝的初步研究

为开拓荔枝转基因育种新途径,以GUS基因作为报告基因,用花粉管通道法转化授粉后24 h的‘新球蜜荔’荔枝雌花,并统计座果率、成苗率、转化率。结果显示：共获得303株实生苗,经PCR检测和GUS染色法证实外源基因整合到4株荔枝苗基因组中,转化率为1.32%。此研究结果为荔枝生物技术育种提供了一种简单有效的途径。     

苦荞粒形相关性状的遗传分析

利用籽粒大小差异较大的2个苦荞品种的杂交后代开展了与产量具有密切关系的粒形相关性状的遗传规律及其性状间的相关性分析。结果表明,F₂和F₃群体的粒长、粒宽、长宽比和千粒重表现值范围都超过亲本的表现值,并且粒长、粒宽和长宽比的变异系数均小于10%,千粒重的变异系数大于10%。另外,粒长、粒宽、长宽比和千粒重的加性方差均大于显性方差,广义遗传率在F₂和F₃代中分别为0.77~0.82和0.82~0.85,固定遗传率都达到0.80以上。粒形性状间的相关性分析结果表明,粒长、粒宽和千粒重相互间都存在极显著的正相关,粒宽和千粒重,粒长和长宽比的遗传相关系数较大。以上结果表明,具有较高遗传率的粒形相关性状可以在后代早期进行选择,但由于这些性状是数量性状而且受多个基因的控制,因此建议继续繁殖后代到基因型稳定,同时考虑性状间的相关性选拔最为有效。     

长节箬竹不同部位叶片生理活性比较

为研究竹类植物不同部位叶片的生理活性并选出较高活性的叶片,对长节箬竹不同节、小枝和叶序的叶片的净光合速率、叶绿素含量和可溶性糖含量进行了测定。结果表明:位于主枝顶端和第1节上的叶片生理活性较强,同一竹节的丛生枝条中边缘小枝的叶片生理活性较强,同一小枝中从顶端往下完全展开的第2～6个叶片生理活性均较强。以上结果可作为竹类植物叶片指标评价的采样依据。     

兜兰花粉活力及柱头可授性探究

本研究以‘绿肉饼’兜兰为试验材料,用扫描电子显微镜对其花粉块进行研究分析。结果显示,花粉块可分为两半,表面光滑呈现紧密网状结构。为获得‘绿肉饼’人工授粉最佳时间,采用TTC (氯化三苯基四氮唑)染色和联苯胺-过氧化氢法进行花粉活力及柱头可授性的研究。TTC染色法结果表明,‘绿肉饼’的花粉活力呈现从弱到强再到弱的趋势,其中开花15~20 d的花粉活力最大,授粉率较高;联苯胺-过氧化氢法结果表明,‘绿肉饼’的柱头可授性随开花时间先弱后强再变弱,其中开花10~20 d的柱头可授性最高。     

基于数字化植物表型平台（D3P）的田间小麦冠层光截获算法开发

冠层光截获能力是反映作物品种间差异的重要功能性状，高通量表型冠层光截获对提高作物改良效率具有重要意义。本研究以小麦为研究目标，利用数字化植物表型平台（D3P）模拟生成了100种冠层结构不同的小麦品种在5个生育期的三维冠层场景，记录了从原始冠层结构中提取的绿色叶面积指数（GAI）、平均倾角（AIA）和散射光截获率（FIPAR_dif）信息作为真实值,进一步利用上述三维小麦场景开展了虚拟的激光雷达（LiDAR）模拟实验，生成了对应的三维点云数据。基于模拟的点云数据提取了其高度分位数特征（H）和绿色分数特征（GF）。最后，利用人工神经网络（ANN）算法分别构建了从不同LiDAR点云特征（H、GF和H+GF）输入到FIPAR_dif、GAI和AIA的反演模型。结果表明，对于GAI、AIA和FIPAR_dif，预测精度从高到低对应的点云特征输入为GF+H > H > GF。由此可见，H特征对提高目标表型特性的估算精度起到了重要作用。输入GF + H特征，在中等测量噪音（10%）情况下，FIPAR_dif和GAI的估算均获得了满意精度，R²分别为0.95和0.98，而AIA的估算精度（R²=0.20）还有待进一步提升。本研究基于D3P模拟数据开展，算法的实际表现还有待通过田间数据进一步验证。尽管如此，本研究验证了D3P协助表型算法开发的能力，展示了高通量LiDAR数据在估算田间冠层光截获和冠层结构方面的较高潜力。     

Isolation and Characterization of GhLEA3 Gene from Upland Cotton and Its Expression in Response to Low Temperature Stress

[Objective] Based on the analysis of cotton GhLEA3 gene structure and its expression model in chilling stress, we investigated the resistance function of GhLEA3 in response to cold stress. [Method] We cloned GhLEA3 from upland cotton by homologous sequence cloning way. We analyzed the properties of the GhLEA3, and constructed phylogenetic tree by bioinformatics analysis. We constructed the transient expression vector 35S∷GhLEA3-GFP by In-Fusion connection technology and studied the subcellular localization of GhLEA3. The expression of GhLEA3 gene in leaves of TM-1 at three-leaf stage under low temperature stress treatments (4 ℃, 24 h) was performed. Agrobacterium tumefaciens mediated floral dipping method was used to transform the gene with expression vector 35S∷GhLEA3-GFP into Arabidopsis thaliana wild type. Low temperature germination experiment at 4 ℃ was conducted to verify germination ability of the transgenic Arabidopsis thaliana T₃ seed. The transgenic Arabidopsis seedlings were treated at 4 ℃(low temperature), and all the leaves were taken to measure their electrical conductivity. [Result] The coding sequence of GhLEA3 gene is 1 218 bp, which encodes 405 amino acids. GhLEA3 protein includes 4 functional domains of PF02987. Phylogenetic analysis showed that the similarity of amino acid sequences between upland cotton GhLEA3 and Arabidopsis thaliana AtLEA3 was 52.6%. GhLEA3 might be mainly localized in vacuoles and small vesicles. GhLEA3 was up-regulated in leaves after low temperature treatment. The germination rate of transgenic Arabidopsis thaliana of T₃ generation at low temperature was significantly higher than that of wild type, and its electrical conductivity of leaves after low temperature treatment was significantly lower than that of wild type. [Conclusion] GhLEA3 belonged to the member of LEA3 family. Phylogenetic analysis showed that GhLEA3 had the closest relationship with AtLEA3. GhLEA3 was induced by low temperature stress and may play an important role in improving cold resistance.