不同氮源对红檬实生苗菌根依赖性的影响

将红檬实生苗培养于改良无土基质中，接种泡囊－丛枝菌根Ｇｌｏｍｕｓｃｉｔｒｏｃｏｌｕｍ，以不接种菌根为对照，并分别施用含氮量相等的３种氮肥，即硝酸按（ＮＯ３－Ｎ）、尿素（ＮＨ２－Ｎ）和硫酸铵（ＮＨ４－Ｎ）。接种菌根１６周后，施不同氮肥的红檬实生苗均有效地感染了菌根，并促进了植株的生长。试验证明，红实生苗施硝态氮（ＮＯ３－Ｎ）使植株的菌根依赖性有明显提高。     

浅谈子宫内膜炎与子宫积脓症的防治

子宫内膜炎是子宫黏膜的炎症；在子宫内贮留大量脓汁即子宫积脓症。     

4株酸奶噬菌体的分离

从上海光明乳业股份有限公司车间发酵罐中分离出4株酸奶噬菌体。1号噬菌体头部呈六角形，平均直径为95.1nm，头部剖面平均面积为8184．8nm^2，尾部的平均直径为18．3nm，平均长度为403．4nm；2号噬菌体头部呈六角形，平均直径为85．4nm，头部剖面平均面积为8046．2nm^2，尾部的平均直径为23．3nm，平均长度为549．4nm；3号噬菌体头部呈六角形，平均直径为95．5nm，头部剖面平均面积为9792．3nm^2，尾部的平均直径为19．8nm，平均长度为450．5nm；4号噬菌体头部呈六角形，平均直径为119．3nm．头部剖面平均面积为12586．1nm^2，尾部的平均直径为23．6nm，平均长度为520．5nm。     

Effect of Split Nitrogen Application on Growth and Yield of Wheat (T. aestivum L.) Genotypes with Different N-Assimilation Potential

A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the 'HNR' genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity ('LNR' genotypes) when an extra dose (40 kg N ha⁻¹) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both 'HNR' and 'LNR' genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha⁻¹) at the time of anthesis increased grain yield of 'HNR' genotypes by 38.5 % as compared to 'LNR' genotypes.     

浅谈鸡球虫病的免疫

鸡球虫病是一种危害性较大的肠道寄生虫病,多发于3个月龄以内的仔鸡.尤以15～45日龄的雏鸡最易感染,近年来,球虫疫苗应用,使工厂生产的养鸡场在鸡球虫病控制方面取得显著成绩.笔者就鸡球虫病免疫在生产实践中的应用,作肤浅论述.     

用分子生物学方法鉴别检测动物源性饲料中的牛羊源性成分

为了防止海绵状脑病疫区和痒病疫区反刍动物源性饲料进入我国 ,非常有必要对贸易往来中的肉骨粉品种来源进行鉴定检测。我们采用分子生物学方法从动物源性饲料中鉴别检测牛、羊特异性线粒体DNA的片段 ,并用限制性内切酶SspⅠ对PCR产物进行酶切鉴定及DNA序列测定。该方法的灵敏度可达 0 .12 5 % ,具有灵敏度高、快速和特异性强的优点。     

盐胁迫对4种禾本科牧草种子萌发和幼苗生长的影响

通过NaCl溶液(0、1.5、3.0、6.0、9.0g/L)处理4种禾本科牧草种子,测定了种子萌发和幼苗生长有关指标。结果表明:美洲狼尾草较耐盐,在9.0g/L盐溶液处理下比其它品种维持了高的发芽率、发芽指数、活力指数,并且其相对值高,以及较高的相对苗长和根长,盐处理显著提高几种牧草幼苗质膜相对透性,总体上降低胚乳的利用速度和利用效率。     

Radiation Balance Components of Maize Hybrids Grown at Various Plant Densities

Components of the energy and heat balances were examined in two maize hybrids grown at three different plant densities (40, 70 and 100 thousand plants per hectare). One of the hybrids was drought tolerant, while the other was bred for cultivation under irrigated conditions. An increase in plant density influenced not only the size of the leaf area, but also the distribution of the leaves at various plant heights. The extinction coefficient, which provides a quantification of radiation penetration, was higher in the irrigated treatments. By contrast to the other two treatments, the plant canopy in the thinly sown stands remained open throughout the vegetation period, and thus behaved quite differently to the closed stands, making it impossible to compare them. Smaller albedo values were recorded for the hybrid bred for irrigation and in thinly sown stands. The low plant density allowed more energy to reach the soil, from which it was reflected, making a considerable contribution to the final temperature in the stand. The latent heat, in keeping with the quantity of water transpired, was the greatest in the densely sown stands. There was little difference between the latent heat values of the normal and dense stands in either hybrid, indicating that they both had a similar sensitivity to increased stand density. If sufficient water is available it would appear that the stand density could be increased even for the drought-tolerant hybrid.     

马立克氏病病毒囊膜糖蛋白B抗原Ⅰ型特异性和群共同性决定簇的单克隆抗体

用能表达马立克氏病病毒（ＭＤＶ）糖蛋白Ｂ（ｇＢ）的重组杆状病毒感染的Ｓｆ９细胞免疫小鼠，制备针对ＭＤＶｇＢ的单克隆抗体。以Ⅰ型马立克氏病病毒ＧＡ株感染的鸡胚成纤维细胞作为检测抗原，同时以免疫荧光试验（ＩＦＡ）和酶联免疫吸附试验（ＥＬＩＳＡ）来筛选杂交瘤细胞，结果获得了ＩＦＡ和ＥＬＩＳＡ均为阳性的２株单克隆抗体细胞株，定名为ＢＡ４和ＢＤ８。在ＩＦＡ和免疫沉淀试验中，单抗ＢＤ８与Ⅰ、Ⅱ、Ⅲ型ＭＤＶ均呈阳性反应；单抗ＢＡ４只对Ⅰ型ＭＤＶ（包括ＣＶＩ９８８疫苗株）呈阳性反应。免疫沉淀反应进一步确证２株单抗识别的是ＭＤＶ糖蛋白Ｂ抗原。     

Use of androgenesis in intersubspecific hybrid rice breeding

Significant differences of callus induction, green plant regeneration and culture efficiency were observed among restorer lines and their hybrids in rice. Average callus induction percentage of F₁, hybrids was about twice that of their parents. Twenty doubled haploid (DH) lines that showed normal fertility with both indica and japonica CMS lines, were selected as widely compatible restorers (WCRs). TG8 derived from CPSLO17/Minghui 63 not only showed normal fertility to both indica and japonica test varieties and CMS lines, but also exhibited superior agronomic traits, in particular short plant, desired plant type, high tillerability, large panicles, good grain quality and resistance to rice blast disease. Strong heterosis for yield was observed in crosses between indica or japonica CMS lines and TG8. TG8 possessed a dominant, widely compatible gene (WCG) that was inherited from the variety CPSLO17. Results confirmed that the anther culture technique is a quick and effective way of developing widely compatible restorers in rice and that it is applicable to the direct use of intersubspecific heterosis with the three-line method.