植物生长调节剂对库尔勒香梨产量与品质的影响

为了明确植物生长调节剂在库尔勒香梨(Pyrus brestschneideri Rehd.)生产中的施用效果,该田间试验以20 a树龄库尔勒香梨为研究试材,研究植物生长调节剂PBO(增效醚,包含细胞分裂素BA与生长素衍生物ORE)、PP333(15%多效唑)和复硝酚钠对库尔勒香梨果实产量及内外部品质的影响,分别设置不同生长调节剂、不同浓度、清水及空白喷施处理,共计17个处理,每处理3次重复。结果表明:喷施植物生长调节剂可以显著提高库尔勒香梨产量,可以降低果皮厚度、果实硬度、果实总酸含量,还可以提高果实脱萼率、红晕果率、果实还原糖含量和维生素C含量,其中以喷施PBO 300倍液效果最佳。与对照处理相比,喷施PBO 300倍液处理的库尔勒香梨产量、红晕果率、脱萼果率及果实还原糖含量分别提高了63.41%、42.01%、38.97%和22.22%,而果皮厚度、果实硬度及果实总酸含量分别降低了26.44%、13.42%和31.3%。     

香茅草精油/羧甲基壳聚糖复合膜的性能及对沃柑采后青绿霉病防治效果

为探寻安全高效的可食性涂膜应用于沃柑保鲜,以羧甲基壳聚糖（Carboxymethyl chitosan,CMCS）和香茅草精油（XMC）两种天然材料为原料制备复合涂膜材料,并检验复合涂膜材料的理化性质,后以蒸馏水为对照,研究0.5%香茅草精油与1.0%羧甲基壳聚糖复合涂膜处理（0.5% XMC-1.0% CMCS）对沃柑果实青霉、绿霉病害的防控效果及其对果实抗病防御酶活性和果实品质的影响。结果表明,香茅草精油的添加提高了膜的韧性、完整性、粗糙度、不透明度,降低了水蒸气透过率。同时,0.5%香茅草精油与1.0%羧甲基壳聚糖复合处理显著（P<0.05）抑制了沃柑果实青霉、绿霉病的发病率及病斑直径的扩展。此外,与对照组相比,0.5%香茅草精油与1.0%羧甲基壳聚糖复合涂膜处理诱导提高了沃柑果皮中苯丙氨酸解氨酶（PAL）、过氧化物酶（POD）、多酚氧化酶（PPO）、几丁质酶（CHI）活性及苯酚、类黄酮、花青素等抗性物质的含量,且在整个贮藏过程中保持了果实品质。综上,香茅草精油的加入提高了复合膜的整体性能,0.5% XMC-1.0% CMCS复合涂膜处理诱导提高了采后沃柑果实的抗病防御酶活性和抗性物质含量,增强沃柑果实抗青绿霉病的能力,维持了果实贮藏品质。     

新城疫病毒F基因在新型杆状病毒表达系统中的表达及重组病毒的免疫原性

将新城疫病毒（四平株）F基因插入到pFastBac Ⅰ质粒中，构建了重组质粒pFF。pFF转化大肠杆菌DH10Bac后，F基因在助手质粒（helper plasmid)提供转座酶的情况下，通过转座进入Bacmid，构建了重组Bacmid(re-Bacmid)。在含有X－gal/IPTG、庆大霉素、卡那霉素和四环素的琼脂平板上，筛选白色菌落后，提取re-Bacmid转染Sf-9昆虫细胞。在昆虫细胞内，re-Bacmid经复制、表达、装配、形成重组杆状病毒，并表达F蛋白。经SDS－PAGE和Western-blot分析，表达的F蛋白的分子大小为63000，并证明在昆虫细胞内表达的蛋白能部分糖基化。表达的F蛋白约占细胞总蛋白的10％。动物试验证明，约建的重组杆状病毒具有良好的免疫原性。     

Subchronic toxicity test for two thermotolerant filamentous fungi used for single cell protein production.

Safety evaluations of two thermotolerant filamentous fungi, Cephalosporium eichhorniae 152 (C. 152) and Rhizopus chinensis 180 (R. 180), grown on a sugar-salts medium were carried out through feeding the biomases to rats at 20% or 40% dietary levels for 90 days. There was a control group fed soybean meal. Weight gain and feed consumption for rats fed 20% C. 152 were equal to those for the control animals, but were depressed in the other three groups, especially the rats fed R. 180. All animals appeared normal and healthy except that transient alopecia was found for a short duration in the fungi-treated rats in the initial period. The cause of this lesion is not clear. At the end of the feeding trial, clinical determinations of constituents in blood and urine samples were conducted. The animals were autopsied and weights for four organs were taken. Histopathological examinations for 26 different tissues were carried out. Mild changes were found in both C. 152 and R. 180-treated rats but most of the these were not considered to be related to treatment.     

水稻不同群体结构的丰产特性的研究

本文根据1961—1962二年试验结果,对三种不同类型的水群体结构,即“少苗促进分蘖”、“中苗促进分蘖”、“多苗控制分蘖”在不同施肥水平下的丰产特性,进行了分析和讨论,结果指出:在施肥量较少时,以“多苗控制分蘖”的群体产量较高;在施肥量较多时,以“少苗促进分蘖”的群体产量较高。本文还从每亩穗数与每穗粒数的关系、叶面积动态以及干物质的积累和分配等方面,进一步分析了上述三种群体结构产量形成过程的特点。关于分蘖的多少对水稻群体发育的影响,也进行了初步的探讨。     

鸡痘病毒282E_4株基因组2.9kbBamHI片段的序列测定与分析

对我国鸡痘病毒 ( FPV) 2 82 E4株基因组 2 .9kb Bam HI片段进行了序列测定与分析。结果表明 ,该片段全长 2 92 3 bp,A T含量为 72 .0 8%,含 6个完整的开放读码框架 ( ORF)和 2个不完整的 ORF,最大的ORF所编码多肽的相对分子质量为 2 4 60 0。在 2个 ORF的上游存在痘苗病毒晚期启动子的保守序列TAAAT,在 6个 ORF的下游和 2个 ORF的编码区内存在痘苗病毒早期转录终止信号 T5NT。把该片段的核苷酸序列和每个 ORF所编码的氨基酸序列分别对 EMBL核酸序列库和 SWISS-PROT蛋白质序列库进行了同源性搜索 ,未发现同源性片段     

Gender,caponization and exogenous estrogen effects on lipids,bone and blood characteristics in Taiwan country chickens

This study investigated gender, caponization and exogenous estrogen effects on lipids, bone and blood characteristics in Taiwan country chickens. Thirty male chickens were caponized at 8 weeks (capons); 15 capons were injected with estrogen (5 mg/bird estradiol 3‐benzoate) every 2 weeks from 8 to 28 weeks, and 15 sham‐operated male (shams) chickens and 15 females were selected for this trial. The results showed that the shams had lower relative abdominal and chest subcutaneous fat than females (P < 0.05). The estrogen‐treated capons had greater relative abdominal and chest subcutaneous fat than shams and capons (P < 0.05), which might result from higher blood very low‐density lipoproteins and triacylglycerol concentrations (P < 0.05). Caponization could dramatically increase relative abdominal fat (506%; P < 0.05). The shams had higher tibia weight and biomechanical properties, such as maximum bone strength and bending moment values than the capons (P < 0.05). Tibia biomechanical properties were reduced by estrogen treatment (P < 0.05). The females obtained the lowest biomechanical value in all treatments (P < 0.05). Histological examination revealed cavity formation in the cortical bone of estrogen‐treated capons and female chickens, which suggested that estrogen reduced bone biomechanical properties by destroying its structural integrity.     

大豆铁结合蛋白基因在旱稻中的表达及铁含量分析

【目的】尝试利用转基因方法提高旱稻铁含量。【方法】采用基因枪和农杆菌转化法，将水稻胚乳特异表达的谷蛋白基因启动子GluB-1驱动下的大豆铁结合蛋白基因转入2个优良旱稻品种“旱稻297”和“旱稻277”。利用PCR、Southern杂交分析方法验证转化结果。【结果】转基因植株T1代RT-PCR证明，外源基因在种子中特异表达。T1～T3代的PCR检测证明铁结合蛋白基因已经稳定遗传。多数转基因植株T0～T3代种子中铁含量高于未转化植株，最高达到未转化对照的2倍以上。【结论】利用基因枪和农杆菌转化法可将大豆铁结合蛋白基因导入旱稻基因组中，并使转基因稻米铁含量增高。     

花叶病大蒜的茎端组织脱毒培养

本文论述了用MS(1962)培养基添加吲哚乙酸(IAA)、细胞激动素(KT)、萘乙酸(NAA)、2,4—二氯苯氧乙酸(2,4—D)、6—苄基嘌呤(BA)等生长调节物质,对开平金山火蒜及广州硬尾骨蒜两品种茎端0.100～0.125mm长的分生组织进行培养,获得了无毒种蒜,并提出了适于此两种大蒜无毒苗培养的培养基配方、生长调节质物的组合和浓度、以及光温条件等一套方案;论证了2,4—D、NAA、BA、光照和温度对愈伤组织诱导、芽分化和球茎形成上的作用,并对大蒜不同组织部位的培养作了初步的探讨。