小粒野生稻酵母双杂交cDNA文库的构建

采用酵母双杂交系统,利用SMART技术,在酵母菌株AH109中构建了小粒野生稻全长cDNA文库,文库容量约为1×106,插入片段平均大小约为640bp。该文库可以用于进一步的酵母双杂交筛选。     

Effects of exogenous enzymes,Lactobacillus acidophilus or their combination on feed performance response and carcass characteristics of rabbits fed sugarcane bagasse

The aim of this study was to evaluate the effect of Lactobacillus acidophilus(LAC), exogenous enzymes of ZAD(exogenous enzyme preparation) or their combination on feed conversion, and dressing of rabbits fed different treatments of sugarcane bagasse(SCB). Five rations were allotted randomly to five groups of New-Zealand White(NZW) rabbits(n=10) with initial live body weight of(838±42.4) g and 5 weeks of age. Rabbits were fed on diets with different sources of fiber as follows,(i) a control diet composed of 100% berseem hay and 0% SCB,(ii) 50% berseem hay and 50% untreated SCB(USCB),(iii) 50% berseem hay and 50% SCB treated with L. acidophilus(LAC),(iv) 50% berseem hay and 50% SCB treated with ZAD(ZAD), and(v) 50% berseem hay and 50% SCB treated with a combination of LAC+ZAD(LZ). Treatments of SCB with L. acidophilus, ZAD and LAC+ZAD had the highest feed conversion ratio than both USCB and control. The dressing percentage of rabbits that fed the LAC and LZ diets was higher(P0.05) compared with that in the other groups. Performance index(PI) for LAC group was improved(P0.05) compared to that for the other groups; however, PI for USCB group was the lowest(P0.05). It could be concluded that treating SCB with L. acidophilus, exogenous enzymes of ZAD or their combination improved feed conversion and performance with more positive effects with L. acidophilus than the other treatments.     

甘蓝型油菜开花期的QTL定位及候选基因鉴定

为了解析油菜开花期性状的遗传机制,利用KN DH群体在冬性、半冬性和春性环境的开花期表型和KN 高密度遗传连锁图谱,通过Wincart 2.5软件的符合区间作图法对油菜开花期性状进行QTL定位及候选基因鉴定。结果显示,共鉴定到119个开花期QTL,单个QTL解释表型变异最大是qFT-13DL16-4 （25.96%）,最小的是qFT-13ZY2-1（2.48%）。利用元分析的方法将初步鉴定的QTL整合为consensus QTL,共获得26个环境稳定表达QTL,包括7个开花期主效QTL。如cqFT-A2-3、cqFT-A2-4在春性环境稳定表达,cqFT-C6-4、cqFT-C6-7、cqFT-C6-12、cqFT-C6-13在冬性和半冬性环境稳定表达, cqFT-C6-14在冬性环境稳定表达QTL。主效QTL置信区间共鉴定到15个与成花诱导相关的候选基因,如 BnaA02g12260D（RGA1）、 BnaA02g15390D（AGL12）、 BnaA02g16710D（LKP2）和BnaC06g19930D（NUA）等,这些候选基因主要涉及赤霉素、光周期、生物钟、春化作用响应和花发育等功能。可见,油菜开花期主效QTL及其候选基因的鉴定为开花期基因的精细定位和图位克隆奠定基础,也为培育早熟、高产油菜品种提供指导。     

Scanning Single-Electron Transistor Microscopy: Imaging Individual Charges

A single-electron transistor scanning electrometer (SETSE)-a scanned probe microscope capable of mapping static electric fields and charges with 100-nanometer spatial resolution and a charge sensitivity of a small fraction of an electron-has been developed. The active sensing element of the SETSE, a single-electron transistor fabricated at the end of a sharp glass tip, is scanned in close proximity across the sample surface. Images of the surface electric fields of a GaAs/AlxGa1-xAs heterostructure sample show individual photo-ionized charge sites and fluctuations in the dopant and surface-charge distribution on a length scale of 100 nanometers. The SETSE has been used to image and measure depleted regions, local capacitance, band bending, and contact potentials at submicrometer length scales on the surface of this semiconductor sample.     

盐胁迫对乌拉尔甘草种子萌发的影响研究

研究了NaCl和Na2SO4不同浓度下两种中性盐胁迫对乌拉尔甘草种子萌发的效应。结果表明:280mmol/L浓度的NaCl和Na2SO4处理时,发芽率高于60%,高浓度的Na2SO4抑制种子发芽强于NaCl;不同浓度Na2SO4处理的发芽高峰期出现比对照早3～5d,比NaCl处理的早2～6d;Na2SO4处理种子的发芽势小于相同浓度的NaCl;溶液浓度大于200mmol/L时,种子发芽指数小于对照,NaCl溶液各梯度处理下的发芽指数均高于相应浓度的Na2SO4。发芽率、发芽势和发芽指数与NaCl和Na2SO4浓度之间呈极显著的负相关,发芽高峰期的出现与NaCl浓度之间呈正相关,与Na2SO4浓度之间呈负相关。     

Plasma Antimullerian Hormone as a Predictor of Ovarian Antral Follicular Population in Bos indicus (Nelore) and Bos taurus (Holstein) Heifers

In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers.     

牧区草地承包经营权流转及其对牧民生计的影响——以内蒙古草原牧区为例

牧区草地承包经营权流转,是伴随草原新三牧政策(休牧、禁牧、划区轮牧)实施、畜牧业增长方式转型、牧区产业结构调整、牧区剩余劳动力转移等过程集中出现,又事关牧区民生与构建和谐新牧区的一个崭新的重要研究命题。本研究阐明内蒙古牧区草地承包经营权流转现状与特征,指出伴随草地流转出现租赁期短、草畜平衡对草地流转限制等问题以及牧区草地流转动因与东中部土地流转不同、草地类型流转程度不同的特征。畜产品是牧民主要收入来源,草地流转价格低影响牧民增收、加大牧区剩余劳动力转移风险。在牧区调研的基础上,提出建立与完善草地承包经营权流转机制的政策建议。     

观赏竹在昆明市园林绿化应用中存在的问题及对策措施

通过对昆明市观赏竹种应用现状的调查,在了解不同竹种的生态习性和生物学特性基础上,分析现阶段观赏竹在昆明城市园林绿化应用中所存在的问题;并根据园林建设的需要提出了改进措施,以期为提高昆明市的观赏竹应用水平提供一定的实践及理论指导。