小麦矮秆种质山农矮330的农艺性状与矮化特性研究

调查分析了山农矮330的综合农艺性状及矮秆遗传特点。结果表明,山农矮330成穗能力强,小穗数多,结实性好,穗粒数多,且综合抗病性较好;携带一对不完全显性矮秆基因,对赤霉酸反应敏感,用其作矮秆亲本时致矮率在20％-30％,对后代的产量性状无明显的不利影响,其矮秆基因的表达受不同遗传背景的影响。     

Mercury's magnetosphere after MESSENGER's first flyby

Observations by MESSENGER show that Mercury's magnetosphere is immersed in a comet-like cloud of planetary ions. The most abundant, Na+, is broadly distributed but exhibits flux maxima in the magnetosheath, where the local plasma flow speed is high, and near the spacecraft's closest approach, where atmospheric density should peak. The magnetic field showed reconnection signatures in the form of flux transfer events, azimuthal rotations consistent with Kelvin-Helmholtz waves along the magnetopause, and extensive ultralow-frequency wave activity. Two outbound current sheet boundaries were observed, across which the magnetic field decreased in a manner suggestive of a double magnetopause. The separation of these current layers, comparable to the gyro-radius of a Na+ pickup ion entering the magnetosphere after being accelerated in the magnetosheath, may indicate a planetary ion boundary layer.     

蒙古虫实化学成分预试验

采用植物化学成分系统预试和专项预试相结合的方法,对采自内蒙古阿拉善盟左旗草场的蒙古虫实地上部分全草进行了化学成分预试验.结果表明,蒙古虫实中含有生物碱、糖、甙类、氨基酸及多肽、皂甙、鞣质、有机酸、黄酮、挥发油、蒽醌;可能含有甾体和三萜类物质、强心甙、香豆素或萜类内脂、酚类物质;不含氰甙和脂肪族硝基化合物.     

豆浆粒径与豆浆品质的关系研究

以未脱皮大豆和脱皮大豆为原料,利用3种主流家用豆浆机(九阳精磨豆浆机JY1、美的无网豆浆机MS、九阳无网豆浆机JY2)分别制备干豆及湿豆豆浆,分析不同豆浆机所制豆浆的粒径及粒度分布规律,进而分析粒径与豆浆品质及蛋白质吸收率间的关系。结果表明:JY2制备豆浆的体积平均粒径D[4,3]最大,MS豆浆的D[4,3]次之,JY1豆浆的D[4,3]最小。湿豆豆浆体积平均粒径小于干豆豆浆,蛋白质含量、蛋白吸收率及感官评分(脱皮豆除外)亦显著高于干豆豆浆,说明湿法可以减小豆浆的粒径,提高原料利用率。脱皮湿豆豆浆感官评分低的主要原因可能是浸泡过程中脂肪氧化酶被激活而产生不良风味物质。     

植物提取液对黄瓜白粉病的抑菌活性筛选研究

首先通过叶圆盘法用29种植物提取液对黄瓜白粉病菌的抑菌效果进行了生物活性测定,初步筛选出槐、黄檀、南瓜和石楠等4种植物的提取液对黄瓜白粉病有较好的预防效果。然后对这4种植物提取液进行预防性和治疗性的室内盆栽药效试验,结果表明黄檀提取液对黄瓜白粉病的预防效果达到72.97%,治疗效果达到91.28%,并且在处理12 d后仍保持42.60%以上的防效。而槐提取液的预防效果和治疗效果分别为79.73%和79.19%,处理12 d后也保持在50%以上的防效。这两种植物提取液均极显著优于对照药剂三唑酮。     

Number of Follicular Waves and Their Effect on Pregnancy Rate in the Cow

In the study, the relationship of follicular growth waves, oestradiol and pregnancy rates were investigated during oestrus cycle in cows. A total of 22, Brown Swiss cows (3-5 years old) were used for the study. The ovaries of animals were examined from sixth day of cycle to next oestrus by ultrasound. The follicles that were present in the ovarium were recorded. Follicular growth was observed every day by means of ultrasound examination. The blood samples were taken for analysis of oestradiol simultaneously with ultrasound examinations. The oestrus animals were inseminated. Each animal that inseminated was examined by ultrasound on day 28 after insemination for pregnancy diagnosis. Two follicular growth waves were observed in nine of 22 (40.9%), three waves in 13 of 22 (59.1%) animals. The oestradiol was found in the same concentration but in different release patterns between two and three waves animals. Pregnancy rate in cows with three and two follicular waves did not differ. In conclusion, emergence of three waves of follicular growth was higher in Brown Swiss cows, the analysis of oestradiol could be used for determination of the wave numbers and the animals with different waves may have had the same pregnancy rates.     

Allometric equations for estimating aboveground biomass of Coffea arabica L. grown in the Rift Valley escarpment of Ethiopia

Coffee, Coffea arabica L., which is native to Ethiopia, is the world’s most widely traded tropical agricultural commodity. While much is known about the productivity and management of coffee for coffee beans little attention has been given to the plants overall biomass production and carbon sequestration. The objective of this study was to develop and evaluate allometric equations for estimating the aboveground biomass of C. arabica plants growing in indigenous agroforestry system in the Rift Valley escarpment of south-eastern Ethiopia. Coffee plays an important role in providing income and in sustaining these productive systems. Biomass harvesting of 31 plants with 54 stems was carried out in a 40 km² area varying in elevation from 1,500 to 1,900 m. The stem accounted for most (56 %) of plant biomass, followed by branches (39 %) and twigs plus foliage (5 %). Plant mean biomass was 22.9 ± 15.8 kg. Power equations using stem diameter measured at either 40 cm (d ₄₀) or at breast height (d, 1.3 m) with and without stem height (h) were evaluated. The square power equation, $ Y \; = \; b_{ 1} d_{ 40}^{ 2} $ , was found to be the best (highest ranked using goodness-of-fit statistics) for predicting total and component biomass. The reliability of the prediction decreased in the order: stem > branches > twigs plus foliage. A cross-validation procedure showed that equation parameterization was stable and coefficients reliable. Our parameterized square power equation for total aboveground biomass was also found to be better than the equations parameterized by Hairiah et al. (Carbon stocks of tropical land use systems as part of the global C balance: effects of forest conversion and options for clean development activities, International Centre for Research in Agroforestry, Bogor, 2001) and Segura et al. (Agroforest Syst 68:143–150, 2006) for C. arabica grown in agroforestry systems, confirming the importance of parameterization of allometric equations with site specific data when possible.