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排序方式: 共有42条查询结果,搜索用时 31 毫秒
1.
核桃早实性状的RAPD分析   总被引:18,自引:0,他引:18  
 用BSA (Bulked Segregant Analysis) 法获得了与核桃早实性状相关的RAPD 标记OPB208900。混合分离群体的混合样来自早实品种辽1 的自然授粉实生后代。用220 个随机引物扩增早实和晚实混合样, 只有引物OPB208 ( 5. GTCCACACGG 3. ) 在早实混合样及其个体上扩增出了约900 bp 的特异带OPB208900, 而在晚实混合样及其个体上无此特异带。用OPB208 为引物, 以19 个品种和3 个株系的DNA 为模板进行扩增,特异带OPB208900在17 个早实品种中的12 个个体上出现, 而5 个晚实品种( 系) 上均无此带。  相似文献   
2.
薄皮核桃新品种‘绿岭’   总被引:6,自引:0,他引:6  
 ‘绿岭’是早实薄皮核桃新品种, 从‘香玲’核桃中选出。与‘香玲’相比, 具有壳薄、果个大、出仁率高、果形美观、稍晚熟(比香玲成熟期晚3~5 d) 等特点。  相似文献   
3.
水分胁迫对早实核桃生长和结果的影响   总被引:6,自引:0,他引:6  
水分胁迫对早实核桃生长和结果的影响谷瑞升,郗荣庭,刘万生(河北农业大学园艺系保定071001)(辽宁经济林研究所大连116031)关键词早实核桃,水分胁迫,生长和结果核桃是重要的经济林树种,早实核桃品种具有很高的栽培价值。然而我国的核桃产区集中于干旱...  相似文献   
4.
AIM: To explore the role of kisspeptin/GPR54 signaling pathway in the pathogenesis of precocious puberty based on female precocious puberty rat model induced by the single dose of danazol. METHODS: Female SD rats aged 3 d were randomly divided into normal group, vehicle group and model group. On the 5th day, the model rats were given a single subcutaneous injection of danazol with ethanol and ethylene glycol mixture. All rats were executed on 15 d, 25 d, 30 d, 35 d and 40 d, and the samples were collected to observe the sexual organ development. The levels of E2, FSH and LH in peripheral blood were measured by ELISA. The Kiss-1 mRNA expression of Kiss-1, GPR54 and GnRH in hypothalamus was detected by real-time PCR. The kisspeptin expression in rat hypothalamus was observed by immunofluorescence. RESULTS: The time for puberty onset and sexual maturation in the model rats was significantly earlier than that in normal group and vehicle group. On days 25 and 30, the levels of peripheral sex hormones and uterine coefficients in model group were significantly higher than those in normal group and vehicle group. On days 25 and 30, the ovarian morphological development in the model rats was significantly earlier than that in normal group. On day 25, the mRNA expression of hypothalamic Kiss-1 and GnRH, and kisspeptin expression of hypothalamic arcuate nucleus in the model rats significantly increased compared with normal group and vehicle group. On day 30, kisspeptin expression of hypothalamic arcuate nucleus in the model rats decreased compared with normal group and vehicle group. On day 35, the mRNA expression of Kiss-1 and GnRH in the model rats decreased compared with normal group and vehicle group. The mRNA expression of GPR54 had no obvious difference among all groups. CONCLUSION: The Kiss-1 mRNA and kisspeptin expression in the model rats with precocious puberty is significantly increased in the hypothalamus during onset of puberty, suggesting that kisspeptin is an initiating factor for precocious puberty. Kisspeptin/GPR54 signaling pathway may play an important role in the occurrence of precocious puberty.  相似文献   
5.
Three groups of twelve 35-day-old rabbits were used for the experiment. Two groups were vaccinated with a mixture of precocious lines of Eimeria magna and Eimeria media originating from corresponding wild strains isolated in Benin. One group benefited of a booster whereas the second one was kept without booster. A third non-vaccinated group was used as control. All groups were challenged per os with an equal mixture of the wild strains of E. magna and E. media at a dose of 104 oocysts per animal. Three weeks after the challenge inoculation, no case of diarrhoea was recorded in the two groups of vaccinated rabbits, as compared to the non-vaccinated rabbits that developed diarrhoea. No mortality was recorded in the three groups. During the patent period, oocyst output of vaccinated rabbits was significantly lower than that of control animals (P < 0.01), confirming a good immunogenic characteristic of the precocious lines. No booster effect was noticed for the boost vaccinated group. The daily weigh gain of the two groups of vaccinated rabbits was significantly higher than that of the non-vaccinated rabbits (P < 0.05). Consequently the precocious lines of Benin origin turned out to be immunogenic and therefore constitute good potential candidates for vaccine production for this country.  相似文献   
6.
中外早熟大豆对大豆食心虫的抗性研究   总被引:1,自引:0,他引:1  
对来自中国、俄罗斯、加拿大、匈牙利、奥地利、德国、法国、波兰等20个国家的336份大豆材料进行大豆食心虫的抗性评价,鉴定筛选出高抗材料58份,抗性材料64份,抗虫材料占34.7%,主要来自中国和俄罗斯。大豆品种抗虫性与大豆品种农业性状进行相关分析,及不同地理生态区大豆资源的抗虫性结果表明:大豆品种抗虫性与与节数、单株粒数、单株粒重、百粒重、豆荚茸毛密度、种皮颜色呈显著相关,大豆植株矮小,籽粒小、豆荚荚毛少,种皮黑色的大豆品种抗虫性较好。  相似文献   
7.
早实核桃的生长发育特点和整形修剪技术   总被引:2,自引:1,他引:1  
早实核桃具有结果早、分枝力强、花枝率高等生长发育特点,宜选择采用自然开心形、疏散分层形和纺锤形等整形方式。根据一些地区的试验结果现多提倡休眠期修剪,但尽可能延期进行以避开严重伤流期,以萌芽前结束修剪为宜。在修剪上应按照树体年龄和特点采取不同的技术。最后提出了修剪中应注意的问题。  相似文献   
8.
从介绍温、光、水、肥等因子对薹蒜生长发育的影响出发,阐述了早熟薹蒜无公害标准化栽培技术,包括栽培方式、合理密植、产地环境、化学投入品的限制等方面,为实现薹蒜无公害早熟生产,达到高产、质优、增效的目的提供了参考。  相似文献   
9.
早熟黄皮洋葱新品种比较试验   总被引:1,自引:1,他引:0  
[目的]对早熟黄皮洋葱新品种进行比较试验。[方法]以洋葱品种喜伯和快星为对照,对连云港市农业科学院选育的早熟黄皮洋葱品种希望之星和阳春黄3号的熟性、性状、不同收获期鳞茎大小、产量等方面进行比较试验。[结果]早熟洋葱在倒伏后鳞茎继续膨大,倒伏后7~10 d后至终收期,鳞茎增加的重量占最终鳞茎重的15%~25%;阳春黄3号熟性最早,产量高于对照品种;希望之星熟性与对照相当,并且在不同收获期均表现产量优势明显。[结论]该研究为优良品种的推广奠定基础。  相似文献   
10.
为选育制备弱毒疫苗所需的毒害艾美耳球虫(Eimeria.necatrix)早熟株,以临床表现、平均增重、相对增重率、小肠病变记分、血便记分、死亡率、每克粪便中的卵囊数(OPG)、卵囊总产量和每个卵囊的繁殖能力为指标,研究了E.necatrix早熟株与亲本株的致病性和繁殖力。结果表明该早熟株与其亲本株相比,早熟株的致病性降低了,接种相同剂量时早熟株平均增重、相对增重率高于亲本株,病变记分、血便记分和死亡率均低于亲本株;早熟株产卵高峰提前,繁殖力下降至亲本株的55%左右,符合球虫早熟疫苗株的特性。  相似文献   
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