不同类型萝卜品种开花习性观察

本试验对不同类型萝卜开花温度、柱头和花粉活力、自交退化原因进行研究,结果表明：萝卜雄性不育系花器结构与保持系及正常植株（自交系）有较大差异,花药发育有黄化、败育、半不育三种类型。冬萝卜花期30－45天,日开花量与温度显著正相关,开花前一天的柱头与当日花粉杂交,结实率最高。春夏萝卜开花受温度、光照等多种因素影响,较高温度时,部分植株能开花,但花药发育不正常,花期短,结实率低。萝卜自交退化与花粉活力下降有关。     

厚轴茶雄性不育株花药败育的生物学特性和细胞学研究

为明确厚轴茶(Camellia crassocolumnaH. T. Chang)雄性不育株花器发育形态、花药和花粉败育时期及兵细胞学特征,利用体视显微镜、石蜡切片技术、染色体制片和DAPI染色法,对厚轴茶雄性不育株和可育株开花迚程、花器形态、花药发育过程、花粉母细胞减数分裂及小孢子发育过程比较观察。结果显示,厚轴茶花属于完全花,花药其四室、呈蝶形,花药壁发育为基本型,绒毡层细胞其双核,于四分体时期形成分泌型细胞,单核花粉期开始降解,花粉母细胞经过减数分裂Ⅰ、减数分裂Ⅱ和胞质分裂后形成四面体型四分体,小孢子呈三角形,成熟花粉为二细胞型花粉。花蕾发育早期,不育株雄蕊发育正常,与可育株无明显差异。花蕾发育后期,不育株花丝弯曲,花药粘连、干瘪、褐化、坏死,不裂药。不育株减数分裂期绒毡层细胞异常增生、排列混乱,单核至双核花粉期绒毡层延迟降解。不育株花粉母细胞减数分裂过程中存在环状单价体、滞后染色体、染色体桥、染色体缺失、不均等分离、微核和多分体等异常现象。不育株小孢子胞质紊乱,单核期花粉粒相互粘附,花粉壁皱缩变形,花粉细胞质和细胞核模糊不清,成熟花粉细胞空瘪凹陷。研究结果表明,厚轴茶雄性不育花器形态属雄蕊萎缩型和花药异常型,花药发育受阻于减数分裂至单核花粉期,存在花粉母细胞败育型和单核败育型。单核花粉期是兵花药败育的主要时期。花药绒毡层异常发育和延迟降解,花粉母细胞减数分裂染色体行为异常,小孢子和花粉粒发育异常可能是兵花药败育的主要原因。     

引种泡核桃开花动态及花粉活力和柱头可授性分析

为探讨开花过程雌、雄蕊成熟期及育性对引种泡核桃结实的影响,以环江县思恩镇引种的两个泡核桃品种‘云新14号’和‘漾濞大泡’为试材,观测两者雌、雄花开花动态和雌花落花情况,测定雄花花粉活力和雌花柱头可授性,并对后者雌花落花胚珠发育进行解剖观察。结果表明,(1)两个引种泡核桃品种花芽能正常生长萌动形成花序,群体花期均在3月下旬至4月上旬,持续14～16 d,雌、雄花开花进程正常,开花类型均接近同时型,且散粉期与柱头可授期重叠8 d,可相互授粉。(2)两个品种雄花不同开花期花粉活力差异显著,自即将散粉期起花粉活力就达60%以上,散粉盛期花粉活力最高,分别高达91.74%和94.69%;雌花不同发育期柱头可授性不同,其中‘云新14号’柱头为"八"型期时,可授性最强,‘漾濞大泡’柱头为反卷期时,可授性最强,为最佳授粉期。(3)‘云新14号’和‘漾濞大泡’雌花在整个花期都存在落花现象,累计落花率分别高达99.58%和84.90%,‘云新14号’分别在盛花期和末花期出现落花大、小高峰期,而‘漾濞大泡’则分别在末花期和初花期出现落花大、小高峰期。(4)‘漾濞大泡’脱落的雌花胚珠萎缩败育,而正常的雌花胚珠呈明显的膨大生长。综上表明,落花是两个品种结实率低、果实产量低的主要原因,大量落花与胚珠萎缩败育有关,后续有必要针对落花问题系统开展自花授粉、品种间授粉、落花机理及人工调节保花促果的研究。     

天津地区野生山樱桃花部结构及生殖特征研究

以天津蓟州区首次发现的野生山樱桃为试验材料,对其花部综合特征、花粉活力、柱头可授性及生殖特征进行研究,以期为樱属植物培育新品种,以及种质资源保护提供理论基础.试验结果表明,山樱桃花瓣直径1.42～1.92 cm,花药黄色,有分泌物,开花时具清香,花期4 d左右;山樱桃花药开裂散粉3 h达到最大花粉萌发率(53.2％);...     

多花黄精开花动态及传粉方式研究

为了研究多花黄精花部特征、开花习性、柱头可授性与传粉方式,在多花黄精花期定株定点记录观察开花习性、观察传粉昆虫;测量花部特征、测定柱头可授性.结果表明,多花黄精4月16日现蕾,4月29日开花,5月4日花朵凋谢.传粉昆虫为马蜂、蜜蜂和蚂蚁等.多花黄精的花冠直径为6.43 mm,花冠营长度约为1.43 mm,花丝长度约为1.00mm,花柱长度约为0.97 mm.开花第1天,柱头即有可授性;花开后第2天柱头可授性较强;花后第3天、第4天柱头可授性逐渐降低,第5天不具有可授性.该试验结果为黄精规范化栽培及良种繁育提供了理论依据.     

Sc2053诱导小麦雄性不育形态学和细胞学观察

应用化学杂交剂Ｓｃ２０５３诱导小麦雄性不育的形态学和细胞学特征观察结果显示，经处理的小麦植株变矮，植株及麦穗呈现浅绿色，穗子呈爆裂状，花药不开裂，呈现雄性不育株的形态特征，这些特征可做为估算小麦群体化学杀雄效果即绝对不育率的依据。经Ｓｃ２０５３处理的小麦雄性不育有无花粉和花粉败育两种类型。无花粉型是在小孢子刚形成时发生败育，从而是产生无花粉的空壳型花药。花粉败育型是小孢子只发育到单核花粉，二胞花粉     

黄金梨雄性不育的细胞学研究

【研究目的】为研究黄金梨雄性不育的早期表现和细胞学特征;【方法】采用石蜡切片法,观察分析了黄金、爱宕和圆黄(对照)的花粉形成过程中,花药和小孢子发育过程的细胞学特征。【结果】黄金梨花粉败育主要发生在小孢子阶段单核晚期;【结论】花粉败育的主要原因是四分体分离后形成的早期花粉细胞, 因绒毡层提前解体,花药维管束细胞木栓化,二者共同导致营养供应困难,致使花粉败育。而对照可育品种花粉经由小孢子阶段很快发育成熟。     

胡萝卜雄性不育株的发现及其形态特征

对田间发现的胡萝卜雄性不育株作了调查与观察,并与可育株作了形态特征比较。结果表明：（１）胡萝卜雄性不育株占群体总株数的０．７８６％。（２）不育花花瓣为绿色,雄蕊为绿色瓣花型,不完全花瓣状,无花丝,花粉;花柱,柱头及子房完全被花瓣状结构所包裹,不易被发现。可育花花瓣为白色,花丝细长,白色,白色花药肥厚,布满花粉;花柱、柱头及子房明显。（３）观察至不育株育性对温度具敏感性。     

谷子Ch型显性雄性核不育花药发育的细胞形态学研究

对谷子Ch型显性雄性核不育花药发育的细胞形态学观察发现,其杂合株花粉发育正常,但开花时花药不开裂;纯合株自造孢细胞期到花粉积累淀粉时均有败育发生,但主要在小孢子期;杂合株的药室壁细胞药隔发育正常;纯合株的药室壁细胞药隔则发生各种异常,可以认为这是其雄性败育的原因.     

软枣猕猴桃花药发育过程中主要激素及矿质元素含量特征分析

本试验以软枣猕猴桃雄株可育花药、雌株不育花药为试验材料,采用高效液相色谱以及原子吸收分光光度法,分析花药发育过程中内源激素和矿质营养的变化,以从生理角度进一步揭示软枣猕猴桃雌株小孢子败育与其的联系,并获得了以下试验结果:雌株不育花药IAA(吲哚乙酸)含量显著低于雄株可育花药;可育花药和不育花药ABA(脱落酸)含量随着花粉发育进程,经过四分体和单核期,差异达到显著水平,ABA含量在达到一定值后抑制了花粉发育的进程,导致了雌株花粉不育的发生;单核期不育花药GA3(赤霉素)含量低于可育花粉,而且可育花药ZR(细胞分裂素)含量高于不育花药,且差异显著。低含量的细胞分裂素类抑制了细胞分裂和组织分化,从而导致了雌株小孢子的败育;软枣猕猴桃雄株可育花药和雌株不育花药矿质元素含量在花粉母细胞时期、单核期以及成熟期差异呈显著水平。     

黄土高原南部地区天水油菜开花生物学研究

为了解和掌握植物的开花生物学特性是开展蜜蜂授粉试验的基础。为更好地利用蜜蜂为黄土高原南部地区的油菜授粉,于2009-2011年连续3年以黄土高原南部地区--甘肃省天水市广泛种植的‘天油六号’为研究对象,对该地区的油菜开花生物学进行了研究。结果表明：对于群体花而言,油菜初花后第9天开始进入盛花期,第31天转入开花末期,盛花期时间为22天;而对于单株油菜,‘天油六号’第9天的单株开花数量显著高于前8天,第19天时达最高,每株开花数可达25.43朵,此后,开花数逐渐减少。而对一天的开花动态研究表明,油菜开花时间主要集中在6:30-12:30之间,其中8:30-10:30为每天的开花高峰期。对油菜花粉活性和柱头可授性研究表明：花后1 h花粉活性最强,柱头的可授性也最强。一天中,9:00-15:00期间所开花花后1 h的花粉活性显著高于其他时间段的花粉活性。     

狭瓣辣木的开花动态及花粉活力和柱头可授性

为了观测狭瓣辣木和多油辣木改良种PKM-1开花散粉时期花部形态、花粉萌发率和柱头可授性的变化规律,本研究采用琼脂培养基萌发法测定花粉萌发率,用联苯胺-过氧化氢法测定柱头可授性,结合田间花部性状随着时间变化的实际观测进行分析。结果表明,狭瓣辣木花朵开花之初,花药即完全打开并开始大量散粉,柱头直立,高于雄蕊;花朵开放后,柱头直立不变,高度逐渐低于雄蕊。PKM-1花朵开花之初,花药微微闭合,2 h后完全打开并开始大量散粉,柱头微微弯曲,高度低于雄蕊;花朵开放后,柱头逐渐弯曲,高度逐渐高于雄蕊。狭瓣辣木花粉萌发率在开花第2天达到最大值77%,呈现先上升后下降的趋势。PKM-1花粉萌发率在开花第1天达到最大值69%,之后迅速降低;狭瓣辣木和PKM-1柱头可授性均呈上升趋势,二者在开花第3天柱头可授性最强。在开花第1天,狭瓣辣木柱头具有微弱活性,而PKM-1柱头没有活性。在自然授粉条件下,狭瓣辣木花期柱头形态不利于其杂交授粉;在开花第2天采集花粉,在开花第3天柱头可授性最强时人工授粉,可以提高狭瓣辣木结实率和杂交成功率。本研究对于制定辣木杂交育种措施、提高辣木人工授粉效率和产量有重要意义。     

Morpho-physiological and phenological attributes of reproductive biology of tea (<Emphasis Type="Italic">Camellia sinensis</Emphasis> (L.) O. Kuntze) in Sri Lanka

A comprehensive knowledge on reproductive traits is a prerequisite in utilizing the existing tea germplasm effectively for crop improvement to develop superior planting material for grower acceptance and market profitability. The Sri Lankan tea germplasm was characterized based on reproductive traits viz. floral morphology, pollen biology, stigma receptivity and phenology of flowering and fruit set. The variability in floral morphology, especially the style morphological features, formed phenotypic clines rather than distinct groups. Studies on pollen biology and stigma receptivity revealed significant variability and asynchrony that could result unequal reproductive success among the genotypes. Four distinct patterns were predictable among the genotypes based on flower and fruit abundance and the time of flowering and fruit set. Three well marked flowering periods occurred in February to April, July and in November. Nonetheless, major flowering period coincided February and March in all the genotypes allowing free crossing between the different genotypes. Profuse mature fruit crop was obtained in February to May. Approximately 26% success was achieved in tea controlled hybridization programmes. Fruits carry two seeds on average and became mature in 8–9 months after pollination. Zygotic development in tea takes more than 1 month after pollination and early embryonic development continued for 4 months after pollination. The indexing of the morpho-physiological diversity and the phenological calendars of flowering and fruit set made available in the study are of significant importance in effective utilization of the tea germplasm for crop improvement.     

Pollen viability and stigma receptivity in <Emphasis Type="Italic">Lilium</Emphasis> during anthesis

Pollen viability and stigma receptivity are prerequisites for successful pollination and seed set in flowering plants. In this study, the pollen viabilities and stigma receptivities of nine Lilium genotypes (six cultivars and three species native to China) were assayed by in vitro pollen germination and the benzidine-H₂O₂ method, respectively. Embryo sac development during anthesis was observed to further ensure the timing of controlled pollination. In addition, the relationship between stigma secretion and stigma receptivity was studied to estimate the pollination time based on phenotype. Anthers cracked on the day of flowering in all genotypes, but pollen germination during anthesis was not observed in Asiatic hybrids excepted for ‘Tiny pudhye’, which exhibited low pollen viability for a short period of time (from 0 to 1 day after anthesis). In the other genotypes, pollen germination rates were highest on anthesis (five of seven genotypes), 0–1 day after anthesis (L. sulphureum), or 0–2 days after anthesis (one Longiflorum hybrid), and then gradually decreased with days after anthesis. While, stigma receptivity first increased and then decreased during anthesis. For most genotypes, stigmas began to be receptive 1 day after anthesis, and all genotypes exhibited stigma receptivity at 2 days after anthesis. The durations of stigma receptivity and strongest stigma receptivity, were genotype dependent, and were 5–8 days and 1–4 days, respectively. Moreover, on the first flowering day, 6 of 7 genotypes had mature embryo sacs, and at the time at which stigmas began to be receptive, all tested genotypes had mature embryo sacs. Some Lilium genotypes showed stigma secretion, which can be a sign of stigma receptivity. Stigmas became receptive and reached highest receptivity within 1 day of the first appearance of secretion on the surface of the stigma and at peaking, respectively. The results of this study are valuable for the implementation of successful Lilium breeding programs.     

葛花粉活力及柱头可授性检测

葛(Pueraria montana (Willd.) Ohwi)自然结实率不高,为了找到可靠的进行科学人工育种方法,本研究以葛为研究对象,采用I2-KI法、2,3,5-氯化三苯基四氮唑(TTC)法对葛花粉活力进行测定,采用联苯胺-过氧化氢法测定其柱头可授性。结果表明:(1)葛的花粉活力在开花前1 d最高,且此时花粉活性最强,开花后随散粉时间延长而逐渐降低,在开花后2~5 d有一个花粉活力较稳定的时期;(2)葛柱头可授性在开花后第1天最强,此后可授性下降并迅速在第5天不再具有可授性。本研究通过对葛花粉活力与柱头可授性进行研究,明确了葛花粉活力与柱头可授性最强的时间,推导出葛的最佳授粉方法是:采集开花前1 d的花粉对开花后第1天的柱头进行人工授粉,为进一步对葛进行科学人工育种提供了一定的数据支持。     

Cajanus platycarpus (Benth.) Maesen as the donor of new pigeonpea cytoplasmic male sterile (CMS) system

Cajanus platycarpus, a distantly related wild species, was successfully crossed with cultivated pigeonpea using embryo rescue and tissue culture techniques. Advance generation lines showed a range of desirable characters including cytoplasmic male sterility. A range of pigeonpea cultivars restored fertility and was maintained by a few lines including cultivar ICPL 85010. Clasmogamous flowers were observed in the male sterile lines. In such flowers anthers did not form di-adlephous bundle. Cytological analysis revealed that meiosis proceeded normally till the tetrad stage in those anthers with pollen grains. After which many of the pollen grains turned sterile. In the anthers with pollen grains, dehiscence was not observed, thus creating functional sterility. In many other anthers, pollen mother cells (PMCs) were not formed at all, giving rise to sepalous anthers. In conclusion two mechanisms of male sterility existed, one was premeiotic, where PMCs did not form and in the second, although PMCs gave rise to pollen grains, they were either partially or totally sterile accompanied by non-dehiscence of anther wall.     

白蜡属植物的开花特性和动态观察

研究花器官形态结构和开花特性,为白蜡授粉受精提供理论依据。本研究选取了3个白蜡品种（‘鲁蜡2号’、‘鲁蜡5号’和‘金箭’）,对其开花特性、花器官构造进行观察。结果表明,白蜡品种雄株花期为11～13天,开花时间比雌株早13～15天;雌株‘鲁蜡2号’的花期为5～6天。3个白蜡品种的小花密集,开花后苞片2裂,花萼钟状4深裂,无花冠。雄花开花后露出舟形花药,花丝极短。雌花苞片开裂后露出雌蕊,柱头成熟时两裂,呈粉红色,花柱极短。扫描电镜下的3个白蜡品种苞片和花萼表面均有盾毛分布,不同品种间盾毛的形态有差异;‘金箭’、‘鲁蜡5号’的花药与花粉结构无显著差异;‘鲁蜡2号’整个雌蕊表面都有不规则褶皱分布。本研究可为进一步开展白蜡属植物的育种和种质资源创新利用研究提供参考。     

棉花细胞质雄性不育花药败育过程中内源激素的变化

利用酶联免疫检测（ELISA）技术,研究了棉花细胞质雄性不育系、保持系、恢复系和杂种一代花药在造孢细胞增殖期、花粉母细胞减数分裂期、四分体至小孢子释放期、花粉发育期和花粉成熟期内源吲哚乙酸（IAA）、赤霉素（GA₃）、玉米素核苷（ZR）和脱落酸（ABA）含量的动态变化。结果表明,在保持系、恢复系和杂种一代可育花药间内源激素含量差异不明显,但在可育与不育花药间差异显著。在IAA、GA₃和ZR含量上,不育花药低于可育花药,但在ABA含量上,不育花药高于可育花药,这种差异在花粉母细胞减数分裂时期达最大值。根据内源激素的功能推测,不育花药IAA含量过低使花药淀粉积累受阻,GA₃含量不足影响花粉母细胞和绒毡层细胞的膨大,过低的ZR含量使花粉母细胞不能分裂形成四分体,过高的ABA含量促进花粉母细胞退化和死亡。