两株气单胞菌的分离与鉴定

从福建省某牛蛙养殖场病死牛蛙和某鸭场病死鸭体内分离到两株细菌，检验结果表明，两株分离菌均为有运动力的革兰氏阴性杆菌。根据其临床症状、细菌培养特性、生化特性、动物回归试验以及溶血试验等一系列试验，研究证明牛蛙感染的病原为嗜水气单胞菌，鸭感染的病原为温和气单胞菌。     

Nitrogen balance in barrows fed low-protein diets supplemented with essential amino acids

This study was conducted to determine the effect of addition of essential amino acids (EAA) to low-protein diets on N balance in barrows. Thirty barrows (Duroc × Yorkshire) with an initial BW of 36 kg were fed 5 corn- and soybean meal-based diets containing 13.6 to 18.2% crude protein (CP) for 10 d in a randomized complete block design. The 18.2% CP diet was formulated without addition of EAA (Lys, Met or Thr). The other diets contained 13.6 to 16.5% CP and were supplemented with EAA to provide 0.83% true digestible lysine equal to that in the 18.2% CP diet. Fecal, urinary, and total N excretion as well as N retention (g/d) decreased with decreasing dietary CP level (P < 0.01). The apparent digestibility of N was almost the same for the 18.2 and 16.5 CP diets, but the value was 2% higher (P = 0.07) than that for the 13.6% CP diet. These findings indicate that, compared with the 18.2% CP diets, supplementation with three EAA to the lowest-protein diets (13.6 CP) is inadequate for maximum intestinal protein digestion, amino acid absorption, or tissue protein deposition in growing barrows.     

陆生固氮蓝藻对土壤环境的影响

我们于１９８８－１９９０－年通过野外调查和室外试验,探讨了陆生固氮蓝藻对土壤环境的影响。试验证明,陆生固氮蓝藻可以利用空气中的分子态氮合成氮素化合物,不断地加富土壤中的氮化物。同时,由于它们大量的繁殖和死亡腐解也增加了土壤中的有机物质使土肿微生物的生长和活动更加旺盛,土     

华夏慈姑种质资源及其研究(上)

介绍了华夏慈姑种质资源的分布、植物学和园艺学分类、生物学特性及生长规律、营养成分，对华夏慈姑的细胞生物学、植物学、栽培学以及病虫害防治等方面的研究进展作了概述，提出了华夏慈姑种质资源研究的基本思路。     

动物福利法的历史起源、现状及意义

动物福利法的基本出发点是让动物在康乐的状态下生存,即减少其所受的不必要的痛苦,并且针对不同动物采取不同的福利标准,让人与动物和谐相处,从而推动社会的文明进步。本文对动物福利法的历史起源、现状及意义进行了叙述,并对动物福利法的立法宗旨、福利标准、结构框架及对中国法制进程的影响等诸方面进行了讨论。     

球孢白僵菌MZ041016菌株对平菇厉眼蕈蚊的毒力

利用球孢白僵菌MZ041016菌株5种孢子悬浮液浓度(3.6×104～3.6×108个/mL)对平菇厉眼蕈蚊成虫和幼虫进行室内毒力测定。在3.6×108个/mL浓度下成虫死亡率最高达86.72%,幼虫死亡率最高达87.69%,成虫的LC50为2.319×105个/mL,幼虫的LC50为3.082×105个/mL。在3.6×104～3.6×108个/mL浓度处理下成虫的LT50依次为8.57、6.14、5.18d和4.28d,幼虫的LT50分别为8.09、6.03、4.96d和4.53d。球孢白僵菌MZ050724菌株在室内对平菇厉眼蕈蚊的成虫和幼虫有较强的毒力。     

Nucleotide sequence homology to bovine viral diarrhea virus 2 (BVDV 2) in the 5′ untranslated region of BVDVs from cattle with mucosal disease or persistent infection in Japan

Cytopathogenic and non-cytopathogenic bovine viral diarrhea viruses (BVDVs) were isolated from cattle with mucosal disease or persistent infection in Japan. These isolates were compared for antigenic properties by cross-neutralization tests with Japanese reference strains of BVDV belonging to classical type 1. Significantly low cross-reactivity to reference strains was noted, indicating the viruses to possibly represent a new serotype in Japan. Thus, to determine the genotype of the isolates, nucleotide sequences of the 5′ untranslated region were determined and compared with those of previously reported BVDV 1 and 2. The isolates were clearly shown to belong to BVDV 2, not to BVDV 1.     

枯草芽孢杆菌抗菌物质对镰刀菌抑制机理的镜下研究

 将枯草芽孢杆菌B-903菌株液体培养72h后,将培养滤液高温灭菌,以不同比例将培养滤液加入镰刀菌孢子悬浮液中,置于扫描电镜和光学显微镜下定时观察。在处理12h后,镰刀菌孢子芽管顶端、菌丝末端及菌丝中央的多处细胞均可发生畸形的球状结构,这种畸变结构随处理时间延长而增加,致使菌丝变成捻珠状。处理36h后,畸变球形细胞及菌丝纷纷断裂离解,细胞内含物渗出,致使大部分细胞成为空泡。到处理48h后,镜下几乎无完整菌丝,均成单个的球状细胞空泡,这些空泡最终胞壁崩裂,不复存在。笔者认为正是枯草芽孢杆菌在生活过程中分泌到体外的抗高温代谢物对镰刀菌孢子和菌丝细胞的这种畸变作用造成拖子和菌丝失活,侵染能力丧失。     

野败型杂交水稻种子纯度室内幼苗鉴定方法研究

通过对野败型杂交水稻及其亲本“三系”和一般常规稻种子在一定浓度的Ａ（盐类化合物）、Ｂ（酸类化合物）试剂溶液里进行光照培养，利用其色素代谢差异使幼苗鉴定器官芽鞘和不完全叶表现色泽不同而达到鉴定野败型杂交稻种纯度的目的。通过２ａ与海南和当地正季生产鉴定相比较，结果显示：用本研究鉴定结果与当地正季生产鉴定结果呈高度相关，相关系数分别为０．９３５１（汕优６３）和０．９００２（协优１０号），同时，１ａ多的生产应用亦表现很高的准确性和实用性。该方法能较好地解决现阶段我国野败型杂交稻种纯度室内鉴定问题而替代海南种植鉴定     

山东省苹果黄蚜抗性水平监测及研究

采用点滴法测定了山东省１０地区苹果黄蚜对氰戊菊酯与氧化乐果的敏感性，结果表明，苹果黄岈对氰戊菊酯与氧化乐果已产生明显抗性，以山东莒南种群为敏感种群，夏津、菏泽、蒙阴、平邑、栖霞、寿光、平度、泰安、荣城苹果黄蚜对氰戊菊酯的抗性比（ＬＤ５０Ｒ／Ｓ）分别为：２３．９３、５２．８３、７４．１７、８３．２４、９１．２２、１０１．９５、１４５．３６、１５７．３３、２９１．５６；对氧化乐果的抗性比分别为：１７．１１、２６．９３、１５．９２、５８．２３、１０６．３２、２８．６９、３１．００、２５．８３、６４．５８。用浸渍法测定了泰安郊区苹果黄蚜对１５种杀虫剂的敏感性和田间４种药剂对荣城苹果黄蚜的药效试验。明确了吡虫啉、硫丹、灭多威对苹果黄蚜毒力高，是防治苹果黄蚜较理想药剂。