玉米品种中单808制种关键技术

玉米品种经营的好坏,不能仅看推广环节,因为品种的推广效果不全是推广环节的功绩,还蕴含着品种的优良特性,高质量的种子才是推广业绩的保障。高质量的优质种子如何生产出来?如何提高制种技术,保证质优量足的市场供应往往成为玉米销售企业年年研究的课题。笔者根据中单808的特征特性和多年积累的制种经验,总结了中单808高产、优质、足量的规范制种技术及相关的风险预防措施。     

Protective role of <Emphasis Type="Italic">S</Emphasis>-methylmethionine-salicylate in maize plants infected with <Emphasis Type="Italic">Maize dwarf mosaic virus</Emphasis>

This study aimed to detect the harmful effects of Maize dwarf mosaic virus (MDMV) infection, and to demonstrate the potential benefits of S-methylmethionine-salicylate (MMS) pretreatment in infected maize (Zea mays L.) plants. The results of chlorophyll a fluorescence measurements showed that in MDMV-infected plants additional quenchers of fluorescence appear, probably as the result of associations between the virus coat protein and thylakoid membranes. It is important to note that when infected plants were pretreated with MMS, such associations were not formed. MDMV infection and MMS pretreatment resulted in a decrease in ascorbate peroxidase (APX) activity in maize leaves, while infection contributed to an increase in activity in the roots. Infection raised the guaiacol peroxidase (GPX) enzyme activity level, which was reduced by MMS pretreatment. MMS contributed to a decrease in both the RNA and coat protein content of MDMV, to an equal extent in maize leaves and roots. The results showed that MMS pretreatment enhanced the stress response reactions against MDMV infection in maize plants and retarded the spreading of infection.     

不同放牧强度下矮嵩草无性系构件组成量化研究

对不同放牧强度下 ( 0 ,2 ,4 ,8只 /hm2 二龄藏羊 )高寒草甸矮嵩草无性系构件组成进行了数量化研究。结果表明 ,随着放牧强度的增加 ,单位面积无性系内矮嵩草分株数、分蘖数、叶片数量及其营养分蘖和生殖分蘖生物量呈减少趋势 ;矮嵩草分蘖节距地面高度略有加深 ,而平均分蘖节直径变化规律不明显 ;生殖分株种子数和分蘖种子数有较明显的增加 ,在重牧区开始减少。随着放牧强度的增加 ,矮嵩草无性系营养和生殖分株生物量以中牧区为最大 ,分别是 6 9 133mg和 91 76 6mg。无性系大小对矮嵩草构件数量和生物量的影响随着放牧强度的增加逐渐减弱     

不同品种马肌肉抑制素基因的克隆与PCR-RFLP多态性分析

肌肉生成抑制素(MSTN)又称GDF-8(growth differentiation fartor8)，属于TGF-β(transformny growth fartor beta转化生长因子)超家族一员。是一种对肌肉具有负调控作用的重要激素。研究以三河马、锡尼河马、乌珠穆沁马、乌审马、纯血马5个不同马种群共250匹为研究材料，对马肌肉抑制素基因的第一内含子进行PCR、克隆、测序，然后进行PCR-RFLP分析，扩增产物经Seal、Mspl、Hhal、DraI、SrfI等5种限制性内切酶酶切，结果DraI在5个种群中具有多态性，并表现为两种基因型(AA和AB)，而其他的内切酶均未发现多态位点。