假单胞菌中抗真菌成分对植物病原真菌准性产孢的抑制作用

我们目前正进行铜绿假单胞菌（PAFS）中抗真菌物质的纯化研究,本文考察对卵菌产孢及菌丝生长具抑制活性的部分纯化成分的特性。PAFS中的初级成分：A1,A2,A3及A6似乎包含2类抗菌组分,A1,A2及A3对子囊菌准性产孢具特异性抑制作用,导致孢子发育不完全,然而有趣的是这些成分对菌丝生长抑制作用不明显。相反,A6对卵菌菌丝生长具抑制活性,另外在含A6条件下产生的孢子萌发的非对称性说明其抗菌活性具有持效性。     

黑穗醋栗亲和性研究

１）人工授粉实验表明，去雄自花授粉处理，野生种兴安茶子的座果率为零，栽培品种的座果率在３０％～５０％之间。实验材料自花授粉座果率低于自然授粉和异花授粉。２）荧光法表明，兴安茶子不去雄套袋处理，在柱头上产生一黄色荧光，花粉不萌发。去雄套袋自花授粉处理，花粉萌发，但花粉管没能进入子房，中途停止生长，栽培品种花粉在柱头上都能萌发，进入子房。３）各材料之间，过氧化物同工酶酶谱有很大的共同部分，彼此之间也存在着差异。兴安茶子花柱柱头部分在Ｃ〔５５．２（３４．１）〕有一明显区别于其它栽培品种的一条特殊谱带。     

茄子新品种龙杂茄5号的选育

龙杂茄5号是以自交系15号为母本，98—5为父本配制的早熟茄子一代杂种，果实长棒形，紫黑色，光泽度好，耐老化，果肉绿白色，细嫩，籽少，果纵径25—30cm，横径5—6cm，单果质量150—200g，每667m^2产量4000kg左右，中抗黄萎病，对褐纹病的抗性较对照强，耐低温、弱光，适于黑龙江省保护地栽培。     

冬小麦短缩茎的维管系统与叶蘖同伸规律

本文通过对冬小麦短缩茎维管系统结构及其发育进程的连续观察,阐明了茎内维管系统在小麦叶蘖生长,尤其叶蘖同伸规律中的作用。     

香石竹茎段培养的适宜培养基

本试验应用茎段培养的方法提高繁殖系数,对基本培养基的无机成份和有机成份进行了研究,筛选出1/2MS—2为香石竹生芽、生根的适宜培养基,单芽年繁殖量可达56万株。     

Tobacco cultivars vary in induction of systemic resistance against <Emphasis Type="Italic">Cucumber mosaic virus</Emphasis> and growth promotion by <Emphasis Type="Italic">Pseudomonas chlororaphis</Emphasis> O6 and its <Emphasis Type="Italic">gacS</Emphasis> mutant

The colonization of plant roots with certain rhizosphere bacteria promotes plant growth and induces long lasting systemic protection against a broad spectrum of plant pathogens. The role of the global regulator, GacS, in the rhizosphere colonist Pseudomonas chlororaphis O6 in stimulating growth promotion and induced resistance against Cucumber mosaic virus was examined in tobacco. Responses were compared in tobacco cvs Samsun and GX3. Root colonization of Samsun with wild-type O6 and the gacS complemented mutant-elicited reduced viral symptoms and viral titre. On GX3, there was little affect on symptoms when roots were colonized by the wild-type, gacS mutant or complemented mutant but colonization by both the wild-type and the gacS mutant lowered viral titre. Wild-type O6 and the gacS mutant caused plant growth to be maintained in both tobacco cultivars after viral infection, although the affect was stronger with GX3 than Samsun. In contrast, although a chemical inducer, benzothiadiazole, reduced symptoms and viral titre in both cultivars, plant growth was suppressed. Our results indicate rhizobacteria-elicited induced viral resistance without a negative impact on growth but there was a differential response between cultivars. Detailed knowledge regarding the mechanisms inherent to these differences between cultivars requires further investigation.     

湖南鸟类新记录——蓝歌鸲

2006年9月29日，在湖南长沙大托铺机场进行鸟类资源调查过程中采到一雀行目鸟类标本，经鉴定为蓝歌鸲，为湖南鸟类新记录。     

Comparative analysis of heart functions in micropigs and conventional pigs using echocardiography and radiography

The production of miniature animals has been suggested for use in organ transplantation. At present, many of the studies about application of animal organs to human have been focused on pigs because of the number of advantages involved and due to their similarities with human. However, a physiological analysis of the organs to be transplanted has not yet been carried out. Therefore, this study analyzed whether or not there were physiological and morphological differences in the hearts of conventionally-reared pigs and micropigs. In this study, the morphological and physiological functions of the heart were examined using radiographic and echocardiographic equipment. In the lateral radiographic view, the heart of the micropig has a larger cardiac long axis : short axis ratio than does the conventional pig, but the difference in the vertebral heart score was not significant. In addition, there were no morphological differences on the X-ray fluoroscopic view. There were no differences in echocardiographic values, except for several values in the left ventricle traces. Overall, it is expected that the values measured in this study will contribute to understanding of the physiological characteristics of micropigs.     

Heterosporis anguillarum infections in farm cultured eels (Anguilla japonica) in Korea

Ten eels (Anguilla japonica) from a fish farm in Korea were examined and diagnosed with a Heterosporis infection. The gross lesions on the trunk were uneven and the concave parts were pasty. Histopathologically, lyses of the trunk muscles, degenerative muscle fibers and the scattered spores were observed. The sporophorocyst (SPC) contained several spores with a variety of shapes. Some SPC were disrupted and the spores in the SPC were scattered in the muscle tissues. Macrophages existed near the scattered spores. Electron microscopy revealed special structures such as sporophorocyst containing various developmental parasitic stages such as meronts, sporonts, sporophorous vesicles and spores.     

Effect of prepartum compensatory nutrition regimen on metabolism and performance of dairy cows

The impact of closely controlled energy management during the dry period upon general peripartum metabolism and the subsequent lactation was evaluated in multiparous dairy cows. Eight lactating, pregnant Holstein cows were paired according to current milk production and body condition score and assigned to either the control or the stair-step compensatory nutrition (SSCN) regimen 16 weeks prior to expected calving date. Control cows were fed according to National Research Council [National Research Council., 2001. Nutrient Requirements of Dairy Cattle. 7th rev. ed. Natl. Acad. Sci., Washington, DC.] recommendations and for ad libitum intake during late lactation and the far-off dry period. The SSCN cows were subjected to dietary energy restriction [80% of net energy for lactation requirements (NE_L)] during late lactation in order to maintain body weight, followed by realimentation (130% of NE_L) during the far-off dry period to induce a compensatory response. A common diet was fed thereafter. The SSCN cows gained less body condition during late lactation and tended to gain more body condition during the far-off dry and transition periods than control cows. There was no difference in dry matter intake during the prepartum transition period and early lactation. Milk yield was not affected by treatment. Serum nonesterified fatty acids (NEFA) were not altered by dietary treatment during late lactation and the dry period; however NEFA were lower in SSCN cows at week 4 of the subsequent lactation. Serum insulin was higher in SSCN cows 8 weeks prior to parturition (end of restriction), tended to be higher at 4 weeks (end of realimentation) before calving, and was also higher at week 12 of early lactation. An SSCN regimen stimulated body condition gain of mature dairy cows during the dry period, did not affect periparturient nutrient metabolism, and led to modest improvements in metabolic parameters later in the subsequent lactation.