蚕豆主要数量性状的遗传主成份和数量分类

对50个蚕豆品种的7个数量性状进行了遗传主成份分析, 初步提出了评选蚕豆品种的遗传主成份标准,并筛选出18个综合性状优良的亲本品种。测定了50个蚕豆品种的遗传距离, 根据遗传距离大小,将50个蚕豆品种聚类为2群、 3类、9组。分类结果指出,蚕豆品种的遗传距离大小与地理差异有些似有一定关系,但在总体上,二者间无必然联系。 Abastract:Analysis of major Genetic component analysis was performed for 7 quantitative characters of 50 faba bean lines and according to the analysis,18 lines were selected as parents.The 50 lines were classified into 2 subpopulations,3 types and 9 groups according to their genetic distance.The results showed that there was seemly a correlation between geographical distribution and genetic distance,nevertheless most lines within the same cluster were close in genetic distance but far in geographic sites.     

遮荫对油用牡丹植株生长和光合特性的影响

设置100%全光照(L0)、50%全光照(L1)、25%全光照(L2)和15%全光照(L3)4种光环境,分析不同遮荫环境对油用牡丹的生长、光合作用及叶绿素荧光参数的影响。结果表明:(1)油用牡丹的花朵数量、比叶重、气孔密度在L2和L3处理下显著低于L0处理,但L1较L0无显著变化;随着遮荫水平增加,油用牡丹种子数量、气孔器面积百分比逐渐下降,且在4个不同处理间差异显著。(2)油用牡丹叶片最大净光合速率(Pmax)、光补偿点(LCP)和光饱和点(LSP)在遮荫条件下均有不同程度降低,L2和L3处理的Pmax和LSP显著低于L0,但L1较L0无显著变化。(3)L3处理的光系统Ⅱ(PSⅡ)的最大量子效率(Fv/Fm)为0.76,显著低于其余3个光照处理;随光化光诱导时间的增加,开放的PSⅡ反应中心的激发能捕获效率(Fv′/Fm′)呈逐渐下降并趋于稳定的趋势,而PSⅡ的实际量子产量效率(ΦPSⅡ)、光化学猝灭系数(qP)、非光化学猝灭系数(NPQ)呈逐渐增加并趋于稳定的趋势,稳定后的Fv′/Fm′、ΦPSⅡ值表现为L0L1L2L3,NPQ大小顺序为L3L2L1L0,但不同处理间的qP无显著差异。研究发现:过度遮荫(15%~25%自然光强)严重抑制了油用牡丹的净光合速率,而且与产量直接相关的花朵数量和种子数量也显著下降,最终造成严重减产;在云南昆明地区50%~100%之间的自然光可能是油用牡丹较为合适的生长光强。     

基于SWMM模型的城市排水区域降雨及地表产流特征

以上海市中心城区典型排水区域为研究对象,基于SWMM模型连续模拟2009—2011年降雨径流,分析区域235场降雨及地表径流特征.结果表明: 该区域发生频率较高的降雨具有雨量小、强度低的特点,雨量为0～10 mm、平均降雨强度为0～5 mm·h^-1、降雨峰值为0～10 mm·h^-1的降雨发生频率最大,分别占所有研究降雨场次的66.4%、88.8%和79.6%,这对于该区域应用低影响开发措施削减小雨量或低强度降雨下的径流和面源污染具有重要意义;径流量总体随着降雨量增大而增大,区域降雨产流临界值不仅与降雨量有关,还与平均降雨强度和降雨历时有关,2 mm以下的降雨基本不产流;2～4 mm的降雨如降雨强度在1.6 mm·h^-1以下,产流量不到1 mm,当降雨量在4 mm以上、平均降雨强度大于1.6 mm·h^-1时,区域基本产流.基于SWMM径流模拟结果,建立适合该区域的径流量与降雨因子的回归方程,其调整R²均大于0.97,能较好反映该区域径流量与降雨因子的关系.研究结果可为该区域更好地规划低影响开发措施和削减排水系统溢流污染提供计算基础,并为类似区域的径流研究提供参考.     

Marker Exchange Mutagenesis of mxaF,Encoding the Large Subunit of the Mxa Methanol Dehydrogenase,in Methylosinus trichosporium OB3b

Methanotrophs have remarkable redundancy in multiple steps of the central pathway of methane oxidation to carbon dioxide. For example, it has been known for over 30 years that two forms of methane monooxygenase, responsible for oxidizing methane to methanol, exist in methanotrophs, i.e., soluble methane monooxygenase (sMMO) and particulate methane monooxygenase (pMMO), and that expression of these two forms is controlled by the availability of copper. Specifically, sMMO expression occurs in the absence of copper, while pMMO expression increases with increasing copper concentrations. More recently, it was discovered that multiple forms of methanol dehydrogenase (MeDH), Mxa MeDH and Xox MeDH, also exist in methanotrophs and that the expression of these alternative forms is regulated by the availability of cerium. That is, expression of Xox MeDH increases in the presence of cerium, while Mxa MeDH expression decreases in the presence of cerium. As it had been earlier concluded that pMMO and Mxa MeDH form a supercomplex in which electrons from Mxa MeDH are back donated to pMMO to drive the initial oxidation of methane, we speculated that Mxa MeDH could be rendered inactive through marker-exchange mutagenesis but growth on methane could still be possible if cerium was added to increase the expression of Xox MeDH under sMMO-expressing conditions. Here we report that mxaF, encoding the large subunit of Mxa MeDH, could indeed be knocked out in Methylosinus trichosporium OB3b, yet growth on methane was still possible, so long as cerium was added. Interestingly, growth of this mutant occurred in both the presence and the absence of copper, suggesting that Xox MeDH can replace Mxa MeDH regardless of the form of MMO expressed.     

假马鞭曲叶病毒和中国胜红蓟黄脉病毒C4蛋白是RNA沉默的抑制子

为了研究中国胜红蓟黄脉病毒(Ageratum yellow vein Chin virus,AYVCNV)和假马鞭曲叶病毒(Stachytarpheta leafcurl virus,StaLCV)C4蛋白的功能,利用烟草脆裂病毒(Tobacco rattle virus,TRV)载体在本氏烟(Nicotianabenthamiana)中分别表达了这两种病毒的C4蛋白,结果发现它们均能在本氏烟中引起类似于病毒侵染的症状,推测AYVCNV和StaLCV的C4蛋白是病毒的致病因子;在RNA沉默的抑制试验中,AYVCNV和StaLCV的C4蛋白均能够在表达gfp基因的转基因本氏烟(16c)上抑制由gfp基因正义链引起的基因沉默的建立,证明它们都是RNA沉默的抑制子。     

根田鼠肾上腺皮质酮水平的日节律及急性低氧的影响

根田鼠肾上腺皮质酮水平的日节律及急性低氧的影响ＴＨＥＣＩＲＣＡＤＩＡＮＲＨＹＴＨＭＯＦＣＯＲＴＩＣＯＳＴＥＲＯＮＥＬＥＶＥＬＡＮＤＥＦＦＥＣＴＯＦＨＹＰＯＸＩＡＯＮＲＯＯＴＶＯＬＥ（ＭＩＣＲＯＴＵＳＯＥＣＯＮＯＭＵＳ）根田鼠（Ｍｉｃｒｏｔｕｓｏｅｃ...     

短尾猴和猕猴在中国安徽省南部的分布

短尾猴(Macaca thibetana)和猕猴(Macaca mulatta)在安徽省的分布见于长江以南,短尾猴限于海拔600-1500米的山地,而猕猴则从平地一直分布到没有短尾猴占据的较高山地。短尾猴所选择的栖息地海拔高度较高,并决定于是否有悬崖和常绿阔叶林。两种猴的分布区,都因人类的严重干扰而缩小。但是,如果其栖息地得到很好的保护,它的种群密度可以接近黄山的水平。两种猴之间的分布界限也反映了它们生态关系的一般形式。