节瓜花芽分化及其性别的田间表现研究

对节瓜4个品种花芽分化的节位进行了组织学观察,并对其开花节位和性别表现进行了统计分析.结果表明:不同品种节瓜的花芽分化规律一致,都在植株第2片真叶展平时期、第6节处开始花芽分化;分化节位与植株展平叶片数之间呈显著线性关系;不同生长阶段花芽分化速率不同,苗期较快,抽蔓期较慢;田间栽培节瓜的现蕾节位和植株花性别表现因品种不同而有明显的差异.     

节瓜果皮颜色遗传规律的研究

用2个果皮青绿色自交系桂优1号毛节瓜、环江节瓜和1个果皮深绿色自交系七星节瓜作亲本,通过正、反交及回交组配,对其杂交组合(桂优1号毛节瓜×七星节瓜、环江节瓜×七星节瓜)的F1、F2、BC1和BC2各世代的果色进行统计.结果表明:F1果色表现一致,无论正、反交均表现为深绿色;F2果色无论正、反交都分离出深绿色和青绿色两种果色,且分离比率接近3:1;BC1(以深绿色的自交系作父本进行回交)果实颜色均表现为深绿色,BC2(以青绿色的自交系作父本进行回交)果实颜色则表现出深绿色和青绿色的分离,分离比率接近1:1.根据经典遗传学原理对节瓜果皮颜色的遗传效应进行了研究,初步推断出:节瓜果实的深绿色与青绿色受一对核基因控制,深绿色对青绿色为显性.     

不同红蓝配比LED光源补光对节瓜育苗的影响

在遮荫条件下,探索不同红蓝配比(红:蓝=7:1,7R1B;红:蓝=5:1,5R1B;红:蓝=3:1,3R1B)LED灯组对节瓜育苗的补光效果,筛选节瓜LED补光育苗的最适红蓝配比.结果表明,红蓝配比3R1B的补光效果最好,可显著提高节瓜幼苗的茎粗、鲜质量和干质量.     

节瓜的大棚栽培技术

节瓜是冬瓜的变种,又名毛瓜。节瓜营养丰富,嫩瓜老瓜均可食用,是菜、药兼用的保健型蔬菜。节瓜在两广普遍栽培,并周年运销港澳。节瓜喜温、耐热、耐贮藏,产量高,对大棚的环境条件适应性较强。我们五年来的试验和生产证明,节瓜大棚栽培不但能提前延后,而且优质高产高效。现仅就其主要特点及其大棚栽培技术简介如下:     

节瓜品种资源对枯萎病抗性评价

为了筛选节瓜枯萎病抗性材料,采用浸根法对20份节瓜资源(经多代自交、分离并最终稳定的自交系)进行枯萎病评价,结果表明:在20份材料中,1号节瓜枯萎病病情指数最高(86.34),13号最低(35.65),1号、20号、3号、9号材料之间病情指数没有显著差异。6个材料(1号、20号、3号、9号、5号和11号)对节瓜枯萎病表现为高感;4个材料(19号、4号、2号和6号)表现为感病;10个材料(15号、7号、10号、16号、8号、12号、18号、17号、14号、13号)表现为中抗,占50%。其中七星节瓜类型发病比较严重,而江心节瓜类型表现较好;因此,江心节瓜类型筛选获得高抗水平节瓜的可能性较高。     

桂林市水果型节瓜品种应用现状及 优势品种推荐

节瓜是炎热夏季的理想蔬菜,水果型节瓜是近年研究出来的市场高端节瓜品种,适合在桂林种植。在介绍桂林地区水果型节瓜应用现状及栽培要点的基础上,提出了生产中存在的问题,并据此推介了甜仙子1号、玉如意、翠玉、甜仙子2号4个潜力品种。     

侵染节瓜的3种病毒多重PCR检测体系的建立

 根据侵染节瓜3种病毒——小西葫芦黄花叶病毒（ZYMV）、番木瓜环斑病毒（PRSV）和黄瓜花叶病毒（CMV）的外壳蛋白基因保守区序列设计特异引物,在建立各种病毒单项PCR技术的基础上,通过优化多重PCR反应条件,初步建立了能同步、快速、灵敏地检测这3种病毒的多重PCR检测体系,为节瓜病毒病原的检测提供了理论与技术支持。     

江门市节瓜生产技术规程

针对目前江门市节瓜种植中普遍存在的滥施农药和落后的生产习惯等问题,特制定节瓜生产技术规程,规范了节瓜的定义及产地环境、品种选择、栽培季节、育苗、整地、定植、田间管理、病虫害防治和采收标准等具体操作措施。     

科葆对节瓜上蓟马的防治效果及对天敌的安全性评价

科葆是由吡虫啉和阿维菌素按一定比例复配而成的新混剂。田间药效试验结果表明,科葆微乳剂和乳油两种制剂对节瓜黄胸蓟马和节瓜亮蓟马均具有良好的防效,800和1000倍稀释液对节瓜黄胸蓟马和节瓜亮蓟马的防治效果分别在96％和90％以上。时两种天敌的室内毒力测定结果显示,科葆两种制剂在推荐用量下对拟环纹狼蛛较安全,对异色瓢虫成虫毒性也较低,但若虫相对较敏感。     

不同砧木嫁接节瓜抗枯萎病效果研究

枯萎病对节瓜的生产危害很大,用适宜的砧木嫁接是提高嫁接成活率、保证节瓜抗病性和增加产量的有效措施。作者分别用南瓜、冬瓜、苦瓜、节瓜等作砧木与碧绿翡翠节瓜进行嫁接,通过人工接种枯萎病菌,探明不同砧木对节瓜抗枯萎病及植株长势的影响,为筛选适用于节瓜的优良砧木提供理论依据。试验结果表明,各参试砧木均可提高节瓜植株的抗病性,促进节瓜植株的生长发育,增强植株抵御枯萎病的能力。其中苦瓜砧木节瓜嫁接苗的抗枯萎病能力强、植株长势好、叶片叶绿素含量高,为节瓜嫁接的优良砧木。     

甜瓜性别分化的研究进展

 甜瓜（Cucumis melo L.）是植物性别分化研究的重要模式植物,近年来虽然其性别分化的机制研究取得了一定的成果,但其性别分化的调控机制尚未完全阐明。本文综述了近几年在甜瓜性别遗传规律、性别决定基因、内源激素、分子标记等方面的研究进展,并加以讨论。     

性诱剂对小菜蛾种群的迷向效果

采用迷向指标,评价了不同成虫密度、不同诱捕器数量对小菜蛾种群的迷向作用。结果表明,自设置性诱剂后的前6d,对小菜蛾成虫的迷向不断增强,10～18d后形成迷向高峰,18d后显著下降。在小菜蛾不同成虫密度下,随着田间菜蛾密度的增加,迷向率呈下降趋势,其中以田间蛾密度为4515～6000头/hm2时,迷向作用最强;同时性诱剂可有效地减少小菜蛾的田间落卵量,对小菜蛾种群的迷向作用105个/hm2效果较好。     

Role of kisspeptin/GPR54 signaling pathways in prompting formation of precocious puberty

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.     

光周期和温度对黄瓜品种‘C09-123’性别分化的影响

以黄瓜品种‘C09-123’为试材,采用植物光照培养箱进行植株培养,利用实体解剖镜观察黄瓜主茎上的雌雄花表现,以探明光周期和温度对黄瓜性别分化的影响。结果表明:低夜温是影响黄瓜‘C09-123’雌性形成的主导因素,光周期影响不明显;12℃的低温条件有利于‘C09-123’雌花形成;在24℃的高温条件下,‘C09-123’在10节内只形成雄花,不形成雌花。     

Ethylene evolution during germination of different sex phenotypes of cucumber

Ethylene production by germinating seeds of cucumber during the first 4 days after imbibition was determined for different sex phenotypes. Ethylene emanation from germinating seeds of gynoecious plants was much higher than from those of the more male phenotypes of androecious, monoecious and hermaphrodite. Ethylene addition and removal (by hypobaric ventilation) during germination caused no apparent changes in subsequent sex expression of the plants. Ethylene production by single F₂ seeds was not closely associated with subsequent sex expression of the plants derived from a cross between gynoecious and androecious cucumbers. These studies suggested that ethylene production during germination was not always closely related to subsequent sex expression.     

温度和光周期对苦瓜性别表现的影响

苦瓜苗期所处的环境条件会影响其性别表现，株洲长白和英引苦瓜品种的光周期反应表现为短日效应，即短日使植株的发育提早，并促进雌性发育，长日的效果恰好相反。苦瓜苗期短日处理时期以出苗至６片真叶（苗龄２０天）为宜。低温可以增强短日效应，高温则使苦瓜的生殖生长推迟，并削弱短日效应，短日低温是苦瓜苗期最适宜的环境条件。     

保护地非化学防控技术集成应用研究

综合评价了防虫网及防虫网与杀虫灯、性引诱剂、病毒等非化学防控集成技术对豇豆甜菜夜蛾等害虫的田间防治效果,结果表明,在豇豆全生育期内采用防虫网进行隔离防治可减少药剂防治5次;防虫网与杀虫灯联合防控前期应用效果较好,后期较差;防虫网与性引诱剂、病毒集成应用对豇豆甜菜夜蛾及其他害虫的隔离防治效果均表现良好。     

芦笋超雄株的DNA 分子标记辅助筛选

 以芦笋两性株自交S₁代雄株为试验材料,首先与优良雌株进行测交,然后利用与芦笋性别决定基因紧密连锁的显性DNA分子标记对苗期各单株进行性别鉴定,推断出超雄株,为芦笋全雄育种提供亲本材料。研究结果表明：显性标记Asp1-T7和Asp1-T7sp特异性好,扩增效果稳定,均能够鉴别芦笋雌、雄性别;一共测验了14株芦笋两性株自交S₁代的雄株,从中筛选出2株超雄株;对田间测交组合单株显花后性别表型调查的结果表明,DNA分子标记检测结果与田间实际相符,2株超雄株所对应的组合被确证为全雄组合。     

Production of fruits with attached flowers in zucchini squash is correlated with the arrest of maturation of female flowers

Summary

Results from two trials carried out under different environmental conditions indicated that the high temperatures reached in greenhouses during the Spring-Summer growing season are the main environmental factor inducing production of zucchini fruits with attached flowers. The fact that the incidence of this characteristic is genotypedependent, with the percentage of fruits with attached flowers varying from 1.4 – 73% among the different cultivars grown during the Spring-Summer season, provides an opportunity for direct counter-selection for this trait in current zucchini squash breeding programmes. High temperatures in the Spring-Summer growing season also induced male-ness in all the cultivars analysed, delaying the production of female flowers, and increasing the number of male flowers on the main stem. Indeed, those flowers that remained attached to harvested zucchini fruits were transformed into bisexual flowers, exhibiting different degrees of stamen development, and were arrested as immature, closed floral buds. A detailed analysis of the maturation and abscission times in female and male flowers of different zucchini cultivars indicated that, although abscission time did not differ, maturation time was longer in male than in female flowers. By comparing sexual expression in different cultivars in different environments, we concluded that inhibition of female flower bud maturation occurs concomitantly with a delay in flower abscission, a process accompanied by the conversion of the female bud into a bisexual bud. Given that Spring-Summer conditions promote the maturation of both female and male flowers, and that the arrest of female flower maturation and abscission are associated with floral sex determination, it is possible that the arrest of female flower maturation is not directly induced by high temperatures, but is mediated instead by hormones such as ethylene or gibberellins.     

杨梅分子生物学研究进展

杨梅(Morella rubra Sieb.et Zucc.)是我国南方重要的特色水果,其果实色泽鲜艳,营养价值高,深受国内外消费者的喜爱。本文综述了杨梅分子生物学的研究进展,主要包括三个方面:杨梅遗传多样性、杨梅基因组学和杨梅雌、雄性别控制遗传模式,展望了杨梅分子生物学今后的研究方向,旨在为杨梅育种及开发利用提供更多的科学参考。