泰国金白花芒花器官及花粉生物学特性研究

为更好地了解泰国金白花芒花器官及花粉生物学特性,对其花的生物学特性、两性花比率及花粉形态进行了观察,并对花粉育性进行了检测.结果表明,花的类型主要为雄花和两性花,花小但量多;两性花比例较低,仅为17.99%,但南面花序初花期两性花比例达到47.83%;其花药饱满,每枚花药含花粉粒408个;其花粉染色活力较低,为14.0...     

SRY-positive 78, XY ovotesticular disorder of sex development in a wolf cloned by nuclear transfer

Recently, we reported the three wolves cloning with normal karyotype from somatic cells of endangered male gray wolves (Canis lupus), but one wolf had female external genitalia. In this study, we conducted further clinical, histological, and genetic analyses. This cloned wolf had a normal uterus but developed ovotestis. Through molecular analysis of the SRY gene, a mutation in the coding sequence of SRY gene could be excluded as a cause of intersexuality. This is the first report of a cloned wolf with a 78, XY ovotesticular disorder affecting sexual development characterized by bilateral ovotestes.     

Sry-negative XX sex reversal in a family of Norwegian Elkhounds

Two related female Norwegian Elkhounds were evaluated at 6 and 8 months of age for enlarged clitori. Both had a 78 XX karyotype. Histology of their internal reproductive tracts demonstrated 1 to be an XX true hermaphrodite with bilateral ovotestes and the other to be an XX male with bilateral aspermatogenic testes. Polymerase chain reaction-based tests of genomic DNA showed that both dogs lacked Sry, the testis-determining gene. Pedigree analysis was consistent with an autosomal recessive mode of inheritance, as has been reported in the American Cocker Spaniel and the German Shorthaired Pointer. This is the 1st reported case of familial Sry-negative XX sex reversal in the Norwegian Elkhound. A summary of 34 previously unreported cases of dogs with masculinized external genitalia and a normal 78 XX karyotype seen from 1980 to 1997 is given.     

Multiple Avenues to Gender in Strawberries

ABSTRACT

Common strawberry cultivars are hermaphrodites, producing both anthers and pistils in their flowers. However, octoploid Fragaria species are trioecious and different genotypes can be female with pistillate flowers, hermaphrodites, or males with staminate flowers. One female selection, F. virginiana High Falls 22 and three hermaphrodite selections, N8688, RH23, and Montreal River 10 were hybridized with five June-bearing cultivars. Seedlings of each family were planted in Ontario and Michigan. Two F. chiloensis selections Pigeon Point (female) and FRA1267 (hermaphrodite), were hybridized with 14 F. virginiana selections. Seedlings from each family were planted in Ontario and Minnesota. In all progeny, the presence or absence of anthers was recorded and a subjective scale used to estimate the percentage of fruit set (1–10 representing 10% intervals). Also, FRA1267 was crossed with one F. × ananassa selection and the progeny intercrossed and grown in Ontario. In the sib-crosses gender was recorded. In two female parents, the female progeny had on average a higher fruit set than the hermaphrodite progeny. F. virginiana genotypes varied in their fruit set, which suggested that there are a number of alleles involved in the fertility of hermaphrodites. In crosses, FRA1267 produced 80% females when used as a female parent and 100% hermaphrodites when used as a male parent. It is thought that the trait is inherited cytoplasmically or that the F. chiloensis alleles involved are epistatic when F. virginiana or F. × ananassa is used as a male parent.     

玻璃海鞘胚胎发育的研究

在显微镜下,对自然排放的的玻璃海鞘C iona intestinalis卵细胞和受精卵以及胚胎发育的整个过程进行了观察,结果表明:玻璃海鞘卵具有特殊的被囊细胞,未受精前的卵径为110μm左右,受精后为160~170μm;在20℃水温下,卵细胞从受精到蝌蚪幼虫孵出需16~18 h,幼虫的浮游时间约2 h,从附着到尾开始收缩约3 h,从尾开始收缩至变态约4 h,从开始变态到变态完全约7~9 d。     

驼背鲈的形态和生物学性状

观察并解剖３２尾活体驼背鲈,详细记录其形态特征和内部组织结构。驼背鲈的显著特征是身躯侧扁,头顶凹入,后头部突然隆起,体甚高,上下颚无犬齿,后鼻孔呈垂直长裂孔;背鳍１０棘,体褐色,体表布满黑色圆点。胃发达,卜型;肠管中等长,幽门盲囊１０～１３个;胆囊非常细长如线状,屈曲,其长为体长的２３％～２５％;生殖腺粗短,雌雄同体。     

两性花野生毛葡萄单株Y17的发现及选育初报

野生毛葡萄单株Y 17是项目组历经8年研究发现的世界上第1株原生种两性花株系,经从广西河池市引种到南宁试种,初步表明,Y 17植株长势中庸,扦插苗种后第3年开花株率达100%,结果枝率90.7%,结实系数2.47,二次花自花授粉坐果率17.8%,平均穗重182.9g,粒重1.48g,果穗大。在生产上可自花授粉结实,也可兼作授粉树,具有重要的科学研究和生产应用价值。     

武汉南湖褶纹冠蚌性腺发育与繁殖周期

1989年2月至1990年1月研究了武汉南褶纹冠蚌的性腺发育和繁殖周期。性腺发育分5期:(1)增殖期,(2)形成期,(3)成熟期,(4)产卵期,(5)休止期或吸收期。繁殖期从秋季9月延续至次年4月,秋季、春季产卵个体各约占60×10~(-2)、30×10~(-2);产卵水温10—27℃,成熟个体产卵3—4次。该蚌体长5cm时开始性别分化,体长约10cm时性成熟,雌雄性比为1.03:1,在研究的446只样本中发现1只雌雄同体个体。     

A hermaphrodite dog with bilateral ovotestes and pyometra

Hermaphroditism was identified in a 3-year-old American Cocker spaniel with an enlarged os clitoridis that was shown as reddish finger-like structure protruding from the vulva. The urethral orifice was located cranially to the base of the os clitoridis. The gonads were situated caudal to the kidneys at the cranial tips of the uterine horns, and were composed mainly of seminiferous tubules and interstitial cells and had ovarian follicles in the cortices. The uterus was enlarged and revealed pyometra. Gross and histopathological findings of the dog suggested hermaphroditism with bilateral ovotestes and pyometra.     

Flower and fruit characters in a kiwifruit hermaphrodite

The dioecious genus Actinidia includes the kiwifruit, A. deliciosa. Currently, the kiwifruit industry is based predominantly on a single female cultivar, 'Hayward', with up to 13% of the orchard canopy in commercial blocks in New Zealand consisting of unfruitful males vines, necessary as pollinizers. The development of hermaphrodite cultivars became a possibility with the identification of inconstant males, which carry a mixture of staminate flowers and bisexual flowers, the latter developing into small fruits containing seeds. This paper describes a hermaphrodite vine, obtained as a rare variant among the progeny from a cross between 'Hayward' and an inconstant (fruiting) male. Testing of pollen from all flowers in one season and measurement of fruit characters after self-setting demonstrated this seedling is completely hermaphroditic, carrying only bisexual flowers, with no restriction on selfing. Although it does not have commercial potential, it will be used as a parent. Perceived benefits from the development of hermaphrodite cultivars include increased productivity, improved pollination, simplified vine management and therefore substantial cost savings. This revised version was published online in July 2006 with corrections to the Cover Date.