Classification of S-alleles by their activity in S-heterozygotes of brussels sprouts (Brassica oleracea var. Gemmifera (DC.) Schultz)

Summary Over a period of many years, data on dominance relationships of S-alleles in Brussels sprouts were collected at URL and IVT. The level of activity of S-alleles in heterozygotes was assessed on the basis of the number of pollen tubes that penetrated into the stigma. 209 out of 210 possible combinations between 21 S-alleles were used for this investigation. The S-alleles were grouped separately for activity in pollen and style on the basis of their sensitivity to lose activity in S-heterozygotes. Besides S-allele interaction per se, activity was found to be influenced by environment and genetic background.Results suggest that in stigma, co-dominance is the normal pattern and that deviations are caused by factors other than S-allele interaction as such.In pollen, only three truly recessive alleles were found. Besides several combinations with mutual weakening in pollen, examples of independent weakening were found.     

杂交水稻超高产制种的技术关键

阐明了杂交水稻超高产制种关键技术 :(1)安排母本比父本早 2天抽穗以充分利用父本初散花粉 ;(2 )利用药物刺激剑叶叶枕分生组织 ,创造最佳授粉态势 ;(3)利用柱头外露敏感期进行特殊技术处理 ,提高母本柱头外露率及柱头外露体积 ;(4 )在父本散粉高峰期人工辅助授粉以及创造超高产制种父母本苗架     

早籼优质不育系95A的选育及应用

９５Ａ是以汕Ａ为母本，用自选的９５占为父本杂交转育而成的野败型优质杂交稻不育系。９５Ａ农艺性状好，抗性较强，不育性稳定，柱头发达外露率高，异交结实率高，易于繁殖制种。９５Ａ配组杂种优势大，优质性状遗传力强，杂种一代米质优。该不育系于１９９６年７月通过技术鉴定。     

Floral biology in the Zanzibar type clove (Syzygium aromaticum) in Indonesia

Summary Investigations of the floral biology of Zanzibar type cloves were carried out on five mature trees. The majority of flowers opened in the afternoon. Anther dehiscence occurred shortly after anthesis and stamens were shed almost 2 days later. Nectar appeared around the base of the stigma as anthers dehisced and remained in evidence for approximately 60 hours. Three days after anthesis a constriction around the tip of the stigma became apparent. The stigma tip subsequently withered, turned brown and was shed after a further four days. Maximum pollen viability and stigma receptivity were attained simultaneously, 48 hours after anthesis. Indications concerning the breeding system in clove are discussed and a procedure for artificial pollination is suggested     

台湾相思开花结实生物学特性研究

通过实地观测,于2017—2018年连续2年对20～23年生台湾相思的开花结实性状进行调查,研究其生物学特性,掌握其生殖特性。结果表明：台湾相思的花蕾形成时间约在3月下旬末期,4月中旬中后期进入初花阶段;4月下旬末期达到盛花高峰期,5月下旬群体开花结束,整个花期持续时间约40 d。群体开花结束后,进入为期约40 d的零星小花期;幼果于4月下旬中后期初现,7月下旬果实全熟,整个果实生长期约90 d;花序一般在夜间开放,开花时雌蕊先于雄蕊伸展并成熟,为雌蕊先熟。开花当天14：00—16：00的柱头具有较高的活性,建议采用该时间段进行授粉;开花当天的花粉活力高达97.64%,花药在晴天时的散粉量明显高于其他天气,散粉高峰期后仍以较高水平（80%以上）持续,建议授粉时在晴天收集当天的花粉;台湾相思的自然花序结荚率较低,连续2年的自然结荚率皆不足25%,荚果含种量以6粒为主,7～8粒次之,稀2～3粒;瘪种数目随果荚含种量的增加而增加。     

刺槐花粉萌发和花粉管伸长生长过程中柱头与花柱内钙离子的分布特征

以去雄后人工授粉的刺槐花为试验材料,并以去雄后不授粉的花为对照,利用焦锑酸钙沉淀法分析刺槐柱头和花柱内钙离子分布对花粉萌发和花粉管生长的影响。结果发现:花粉在萌发前,其萌发孔聚集了大量的钙沉淀。授粉作用会很快促使柱头表面泡状分泌物和胞外基质钙含量增加。随着大量花粉萌发完成,柱头泡状分泌物内的钙含量开始下降,但是柱头胞外基质的钙含量下降不明显,这表明柱头泡状分泌物的钙离子对花粉萌发可能有促进作用。刺槐的花柱含有一个中空花柱道,中空花柱道周围有一层通道细胞,不论授粉与否,通道细胞液泡和细胞壁上都有大量钙离子,这些钙离子对花粉管的生长可能有诱导作用。刺槐花柱内的钙离子梯度现象不明显。本研究结果有利于揭示刺槐乃至其他豆科植物柱头和花柱内钙离子分布对花粉萌发和花粉管生长的影响。      

锥栗开花授粉生物学特性

通过田间调查、花粉离体萌发、石蜡切片和人工授粉等试验手段对锥栗的开花动态、花粉活力、柱头可授性、风媒传粉特性和授粉特性等进行研究。结果表明：锥栗雌花群体分化时间约40天,单花分化时间约22天,柱头可授性持续期为7天;雄花序4—5月开花,群体花期23～26天,群体盛花期13～15天,单花序花期10～12天,开花后6天内花粉保持较高活力。风媒传粉是锥栗传粉的主要途径,风速和风向是影响锥栗传粉的主要气象因素,顺风方向上花粉的传播距离及花粉通量显著高于其他3个方向。锥栗在去雄套袋且不进行人工授粉的处理下未坐果,表明锥栗不存在无融合生殖;异交授粉坐果率均显著高于自交,表明异交能显著提高锥栗坐果率,生产上需配置授粉树。     

檫木花粉活力和柱头可授性研究

通过野外观察檫木Sassafras tzumu（Hemsl.）Hemsl的开花过程,用联苯胺—过氧化氢法测定其柱头可授性,TTC的方法测定檫木花粉活力。结果表明：柱头具可授性时间为8 d,檫木的花粉活力持续时间为32 h。根据测定时间发现柱头可授期和花粉活力较强期重叠较长,通过后期观察到檫木有结实,说明檫木具有正常的传粉机制和结实能力。     

广玉兰开花动态与雌雄异熟机制的研究

通过野外观察,运用人工授粉、噻唑蓝（MTT）、柱头压片等方法,对广玉兰开花动态、花粉活力、柱头可授性、雌雄异熟机制进行研究。结果表明：1）在广玉兰为期5—6d的单花开花过程中,存在二次开合现象;2）广玉兰开花后花粉活力随开花进程逐渐减弱,初次开放阶段是柱头最佳可授期,对异株异花、同株异花及自花授粉皆具可授性;3）广玉兰...     

青杨派树种雌蕊柱头可授性及最佳授粉时期

为提高青杨派树种有性杂交和多倍体诱导效率,以小青杨、小叶杨和哲引3号杨等青杨派树种及杂种为材料,用过氧化物酶试纸溶液测试结合授粉观察的方法对其雌蕊柱头可授性及最佳授粉时期进行了研究。结果表明: 在温室水培条件下,青杨派树种花序可授期持续4～5 d; 花序不同部位雌蕊柱头获得可授性的时间不同,基部雌蕊柱头最早获得可授性,而顶部雌蕊柱头获得可授性最晚; 过氧化物酶试纸溶液在具有可授性的柱头表面呈现蓝色阳性反应,在育种实践中,可以应用过氧化物酶试纸溶液快速、有效地对青杨派树种雌蕊柱头可授性进行检测; 3种青杨派树种雌花序柱头最佳授粉期为花序顶部露出芽鳞84～96 h,以此为参照点,对于适时施加理化处理诱导胚囊染色体加倍选育青杨三倍体等工作具有重要的指导价值。