Isolation,Identification and Biological Characteristics of Staphylococcus chromogenes from Tibetan Pigs

In order to understand the infection of Staphylococcus disease in healthy Tibetan pigs in Linzhi city,Tibet.232 samples were collected from the slaughterhouse in Bahe town,Gongbujiangda county,Linzhi city,Tibet,the teaching practice ranch at the Tibet Agriculture and Animal Husbandry University in Bayi district,Linzhi city,and the slaughterhouse in Bayi district,Linzhi city.These samples were isolated,cultured and identified,and one isolated strain was systematically studied for biological characteristics.Epidemiological survey results showed that 73 of 232 samples were positive for Staphylococcus,the positive rate was 31.47%,16 positive samples were detected in the slaughterhouse of Bahe town,Gongbujiangda county,Linzhi,Tibet,with a detection rate of 23.89%(16/67),43 positive samples were detected in the pastures of the teaching practice ranch at the Tibet Agriculture and Animal Husbandry University in Bayi district,Linzhi city,with a detection rate of 34.40% (43/125),14 positive samples were detected in the slanghterhouse in Bayi district,Linzhi city,with a detection rate of 35.00% (14/40).Through PCR identification,gene sequencing and biochemical identification,5 strains of Staphylococcus chromogenes were isolated,and one of them (Sa LZ1) was studied systematically.The biological characteristics of the isolated strains showed that the Sa LZ1 strain formed round white convex colonies on the agar medium,with regular edges,smooth surfaces,and opaque white colonies.The isolates were Gram-positive cocci bacteria.PCR sequencing results showed that the isolate had the highest homology with Staphylococcus chromogenes (GenBank accession No.:MG576253.1),positive for serum inulin,manicol,glucose,saccharose,lactose,negative for arabinose,sodium hippurate,raffinose,xylose,urea,etc,consistent with the biochemical characteristics of Staphylococcus chromogenes.The logarithmic growth period of isolated bacteria was 5 to 10 h.The pathogenicity test of mice showed that the mortality rate of mice reached 100% when the concentration of Sa LZ1 strain reached 3.5×10⁹ CFU/mL.And the results of pathological section showed that Sa LZ1 strain could cause the visceral tissue of mice to develop pathological changes.The above results provided a theoretical basis for the prevention and control of Staphylococcus suis in Linzhi,Tibet.     

三色农业

中国农科院研究员、“三色农业”的倡导者包建中先生认为，传统农业是“绿色农业”，开发利用海洋生物资源的“海上牧场”可称为“蓝色农业”．而利用微生物资源的农业开发，则可称为“白色农业”。由于这3种农业模式都可以提供食物、饲料和工业原料．因此又被统称为“三色农业”。所谓“三色农业”是指绿色农业、蓝色农业和白色农业，具体含义如下。     

彩叶植物叶片呈色影响因素浅析

对彩叶植物的呈色原理及影响叶片呈色的因素进行了阐述,以期对彩叶植物的研究及栽培应用提供参考。     

基于贝叶斯向量自回归的区域经济预测模型：以青海为例

十七年文学出于对革命意识形态的绝对捍卫,对土匪的想象缺少了民国时期作品的丰富性,其匪类叙事反映了主流意识形态对于文学匪色想象的绝对控制和规训。然而传统英雄侠义观的根深蒂固以及古典英雄传奇叙事模式的影响使匪色想象逸出意识形态的控制,塑造了新的类型形象——具有匪性气质的革命英雄人物。同时在十七年文学中还存在一个异数——那就是诗人郭小川的叙事长诗《一个和八个》,它体现了逸出秩序之外的个性化匪色想象,也使诗人因此受到严厉的政治批判。     

地理位置与甘蓝型黄籽油菜粒色关系的研究

供试材料甘蓝型黄籽油菜杂交种"渝黄1号"分别种植在7个不同经纬度的生态点,研究了地理位置对甘蓝型黄籽油菜粒色的影响.结果表明,纬度与甘蓝型黄籽油菜粒色的变化有一定关系,随着纬度的升高,甘蓝型黄籽油菜黄籽度逐渐增加,粒色变淡,表明高纬度可能不利于种皮色素的形成.     

果胶脱色技术研究进展

果胶脱色技术是影响果胶生产质量的重要因素,就果胶的呈色机理,活性炭脱色、醇氨溶液脱色、双氧水脱色、树脂脱色等方法进行了综述。     

色叶类藤蔓植物在园林植物配置中的应用

色叶类藤蔓植物是新世纪室内外重要的绿化美化材料,本文综述了色叶类藤蔓植物的分类、选择和应用方式,并对色叶类藤蔓植物的研究方向进行了探讨。     

二色茉莉组织培养技术体系研究

以茎段为材料,采用不同培养基,研究确定适合二色茉莉(Brunfelsialatifolia)组织培养的培养基类型,植株再生的可能途径,以及适宜的培养条件。结果表明:①培养条件为温度25±2℃,光照强度1500～2000lx,光照12h/黑暗12h;②初代培养以MS+BA1 0mg/L+NAA0 01mg/L为最佳组合配方;③接种后直接进行光照培养启动较快;④0 1%升汞对外植体处理时间6min效果最好,启动率达91 5%,污染率2 5%;⑤继代培养以MS+BA2 0mg/L+NAA0 05mg/L为好,其月增殖系数为6 11,丛生芽多且生长适中,30d便可增殖一代;⑥生根培养以1/2MS+IBA2 0mg/L为好,其生根率为93 3%,平均根数为2 85条,平均根长为2 52cm;⑦生根移栽到珍珠岩∶蛭石=1∶1的育苗基质中,30d后成活率为85 9%。     

香蕉果汁的防褐变技术研究

以香蕉果肉为原料,采用果胶酶酶解的方法,先对香蕉果浆进行高温钝化酶处理,再通过正交试验来研究香蕉果汁防褐变的最佳工艺条件。探讨了温度、时间、pH值对护色效果的影响,获得的最佳工艺条件是:将一定量的香蕉果肉置于95℃初始护色溶液,其体积(mL)为原料重量(g)的2倍,并持续加热5min,酶解,然后加入含柠檬酸0.32%、维生素C0.06%、EDTA0.10%、植酸0.02%的混合护色液。此方法可使香蕉果汁保持2～3个月不发生褐变,保证了其在较长时间内的品质要求,提高了香蕉制品的附加值。     

五色草的栽培与应用技术

白草、绿草、小叶红、大叶红、小叶黑合称五色草。五色草因其颜色鲜艳 ,枝繁叶密 ,耐修剪 ,而成为黑龙江省花坛的特色花卉 ,它既可与草花搭配栽植模纹花坛 ,又可单独拼字、拼图案 ,还可栽植立体花坛。现将其栽培与应用技术介绍如下。1　品种及其特征特性a .白草 (Sedumlineare)