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排序方式: 共有198条查询结果,搜索用时 15 毫秒
91.
Adolfo Rosati Marija Zipani
Silvia Caporali Giuseppe Padula 《Scientia Horticulturae》2009,122(3):399-403
Fruit size is an important parameter both for scientific understanding and for commercial purposes. In many species, mature fruit size is often related to floral ovary size, but no literature exists in olive that demonstrates such a relationship. Previous work suggests that olive cultivars with different fruit sizes have similar cell number and size in the ovary transectional area, but ovary and fruit dry weight was not measured. In the present study, ovary dry weight and fruit dry weight during the whole fruit development season until harvest were measured in olive cultivars with different fruit size, over three years. Flower dry weight was also measured. Fruit weight at harvest was strongly correlated to ovary weight at bloom, both in single-year data and when data from three years were pooled. Flower dry weight, excluding the ovary, was also correlated to ovary dry weight. Ovary dry weight was strongly correlated not only to the fruit dry weight at maturity, but also at any date during fruit development. The mature fruit/ovary dry weight ratio ranged between 1000 and 4000 among cultivars, but was not correlated to the fruit dry weight at maturity. These results suggest that, in olive, fruit weight is genetically controlled through the ovary weight at bloom. This knowledge may have implications in the understanding of fruit set and source-sink relationships in olive. 相似文献
92.
本研究系采用中西兽医结合的方法,首次应用国产LRH-A穴位注射后海穴、百会穴和催情穴(任选一穴)治疗因卵巢机能失调所造成的不孕症奶牛共177例,总有效率达73.6~100%,与肌肉注射疗法比较,提高疗效10.7%左右,用药量比肌肉注射节省2/3~4/5,取得了满意效果。在探索其治疗机理方面,测定了血浆中孕酮(P)和17β一雌二醇(E_2)的含量变化,提供了一定依据。 相似文献
93.
94.
卵巢打点注射质粒pIRES2-EGFP生产转基因兔的研究 总被引:1,自引:0,他引:1
本研究以绿色荧光蛋白为报告基因,转染兔卵母细胞,探索建立操作方便、效率高、成本低、可定量生产转基因兔的可行性方法.选择14只成年新西兰雌兔,每侧卵巢内分别打点注射0.25 mL 0.5~0.8 mg/mL的质粒,注射后第3日、第16日和第31日进行人工辅助配种;卵巢注射后第3日、第16日和31日随机各取1只雌兔卵巢做冰冻切片,置荧光显微镜下观察绿色荧光;应用PCR 和 Southern 杂交检测转基因新生仔兔阳性率.结果经荧光显微镜观察,卵巢注射后第3日配种的雌兔卵巢冰冻切片及48 h以后的胚胎呈现绿色荧光;卵巢注射报告基因后第3日配种的雌兔后代阳性率最高,PCR 和 Southern 杂交检测结果分别为72.7 %和45.5 %;第31日配种的后代阳性率最低,分别为36.8 %和15.8 %;第16日配种、第3日配种和第31日配种雌兔的阳性后代数量呈递减趋势.卵巢注射后第3日配种,虽然后代阳性率较高,但是其产仔数最少.实验结果表明,用注射器直接对卵巢打点注射外源基因生产转基因兔的方法操作简便、高效,为日后大规模制备一些大型家畜的转基因后代奠定了基础. 相似文献
95.
以甘蓝型波里马胞质雄性不育系油菜为母本,与青花菜杂交,在授粉后不同天数,利用不同的培养基对其种间杂种的子房进行培养,利用Nitsch(1956)和改良White(1963)培养基所培养获得的种子数和幼苗数均多于Ms和1/2Ms培养基。从幼苗数目来看,培养的时间越早,其幼苗数目越多。 相似文献
96.
芥蓝×诸葛菜属间杂种的获得 总被引:8,自引:1,他引:8
用子房培养和胚培养相结合的方法,获得了芥蓝×诸葛菜属间杂种。授粉后14d和18d的子房在附加IAA2mg/L和KT0.5mg/L的MS培养基上培养,结籽率分别为54.3%和46.2%。在附加IAA0.2mg/L和KT2mg/L的MS培养基上,种子萌发率为13.3%。其F1形态介于双亲之间,花粉无活力,开放授粉不能结籽,染色体数为21,是双亲单倍染色体数目之和。 相似文献
97.
Gay Marsden David Hewitt Eric Boglio Peter Mather Neil Richardson 《Aquaculture (Amsterdam, Netherlands)》2008,280(1-4):242-246
There is mounting evidence that the terpenoid hormone methyl farnesoate (MF) plays important roles in regulating reproductive processes in crustaceans. To gain further information on its roles and possible modes of action, MF was orally administered to ablated Penaeus monodon at a concentration of 5.5 μg per gram of diet, and a range of reproductive performance criteria measured. Results confirmed that MF plays a role in the reproductive process of this species. Specifically, under the conditions of this study, MF inhibited late stage ovary development and reduced fecundity in ablated prawns. The impact of the artificial diet (without additional MF) relative to a squid–mussel diet, was also assessed in this study and although it increased the quality of larvae produced, it also increased inhibition of late stage ovary development. Thus while the current study has increased our knowledge of MF by isolating an ovary developmental stage at which MF regulates reproduction in P. monodon, factors that determine the extent of its effect and whether it has a stimulatory or inhibitory effect, remain unknown. Until these factors are identified, the application of MF as a means of predictably manipulating egg production in captive prawns remains problematic. 相似文献
98.
A. Supriya K. Raghuveer I. Swapna M. K. Rasheeda T. Kobayashi Y. Nagahama Aparna Dutta Gupta K. C. Majumdar B. Senthilkumaran 《Fish physiology and biochemistry》2005,31(2-3):267-270
In the present study, thiourea-induced thyroid hormone depletion and thyroxine (T4) ‘overdose’ were used as a strategy to understand the influence of thyroid hormones on ovarian recrudescence of juvenile
(3-months-old), immature (8-months-old) and adult (1-year-old) air-breathing catfish, Clarias gariepinus. Thiourea-induced thyroid hormone depletion in juvenile catfish impaired ovarian development, but no significant effect was
observed in immature catfish and during late stage of ovarian recrudescence of mature catfish. T4 treatment in females undergoing late stages of ovarian recrudescence induced rapid oocyte growth by promoting its early entry
into maturational phase as evident from the presence of more number of vitellogenic and post-vitellogenic follicles, decrease
in aromatse immunoreactivity and reduced estradiol–17β levels. Hence, thyroid hormones have an important role to play during early stages of ovarian development and vitellogenesis
of catfish and also indicating that thyroid has a stage dependent effect on ovary. 相似文献
99.
Wei Ge 《Fish physiology and biochemistry》2005,31(2-3):209-214
Pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), play fundamental roles in vertebrate
ovarian development and function. However, there has been an increasing body of evidence that the actions of FSH and LH are
mediated or modulated by a variety of locally produced peptide or protein factors, which form an intimate regulatory network
within and between the ovarian follicles. In the past few years, a variety of growth factors have been identified and characterized
in the zebrafish ovary including activin and epidermal growth factor (EGF), which are important components of the intraovarian
communication network. To understand how this local network interacts with the gonadotropins from the pituitary, we have recently
cloned and characterized all the subunits of zebrafish FSH and LH from the pituitary as well as their receptors (FSHR and
LHR) from the ovary. Using the Chinese hamster ovary (CHO) cells as the bioreactor, we have produced recombinant zebrafish
FSH and LH with biological activities. With the recombinant hormones available, the functions of zebrafish FSH and LH in the
ovary and their interactions with the local factors will be an important issue to address in the future. This review briefly
summarizes some recent work from our laboratory and others on both gonadotropins and their potential intraovarian signaling
factors in the zebrafish. 相似文献
100.
以色素万寿菊雄性不育株未授粉子房为外植体,比较研究子房发育期、高低温处理和生长调节剂组合对愈伤组织诱导和分化的影响。结果显示:发育6~10 d,花丝刚好露出花萼,顶部呈圆柱状的花蕾愈伤组织诱导效果最好,为79.2%;低温预处理3 d,高温培养5 d有利于愈伤组织诱导;MS+2,4-D 0.5 mg/L+NAA0.5 mg/L+6-BA 0.5 mg/L+KT 0.5 mg/L为愈伤组织诱导最佳培养基,诱导率高达85.8%;NAA 1.0 mg/L+6-BA3.0 mg/L为不定芽分化适宜培养基,分化率达77.6%;1/2MS+NAA 0.2 mg/L为生根适宜培养基,生根率93.5%。本研究可为建立高效单倍体培养体系以及单倍体育种技术提供基础性资料。 相似文献