抗菌肽基因Gnk2-1经花粉管通道法导入西瓜的初步研究

 通过花粉管通道介导银杏抗菌肽基因Gnk2-1 于西瓜自交系‘04-1-2’中，以浓度为100、200、 300 和400 ng · μL-1 的DNA 为供体，分别于授粉后24、27、30 和33 h 导入，对子代进行PCR 检测。结 果表明：T0 代坐果率和单瓜结籽数随授粉后处理时间的增加而升高，但在各个处理时间下均显著低于对 照；外源DNA 的导入对授粉后27 h 处理的T1 代种子发芽率和授粉后24 h 处理的T1 代种子出苗率均造成 显著降低；不同DNA 浓度转化的T1 代种子的发芽率和出苗率与对照相比差异不显著；对1 280 株T1 幼 苗进行PCR 检测，得到32 株阳性转化植株，总体转化率为2.5%，最佳转化时间为授粉后24 ~ 27 h，最佳 DNA 转化浓度为100 ~ 200 ng · μL-1；PCR 阳性植株抗病鉴定表明转基因植株对西瓜枯萎病的抗性有所增强。     

花粉管通道法在番茄转基因上的应用

为提高花粉管通道法遗传转化率,现设计了自交授粉后对番茄的花柱分别进行4种依次加大切割深度并滴加外源基因的处理,待转化果实成熟后收获转化种子。对各处理的坐果率和结籽数/果进行统计分析。结果表明:随着花柱切割深度的加大,坐果率和结籽数/果均显著下降;对T1代植株进行PPT抗性筛选、PCR检测阳性率后表明,不同深度切割处理对植物材料的转化率差异不显著。切除柱头+1/3花柱的处理方式进行花粉管通道法遗传转化操作,能获得较好的效果。     

核桃雌花状态和不同授粉方式对花粉萌发及花粉管生长的影响

【目的】从核桃生殖生物学角度出发,研究雌花状态和不同授粉方式对新疆早实核桃花粉萌发及花粉管生长的影响,旨在了解核桃授粉受精过程的基本规律,以期为提高核桃坐果率及果实品质提供科学依据,对于核桃品种选育、品种改良以及生殖隔离研究等均具有重要意义。【方法】以乌什县主栽核桃品种‘新新2号’(Juglans regia‘Xinxin 2’)为试材,运用荧光显微技术研究核桃雌花状态附着花粉的能力和不同授粉方式(自然授粉、人工辅助自花授粉、人工辅助异花授粉)下花粉粒在柱头上的萌发及花柱中花粉管的生长状况。【结果】(1)各时期雌花柱头附着花粉数量之间存在极显著差异(P<0.01),显花期和始花期柱头不具备附着花粉的能力,V字期柱头附着花粉的数量明显低于小八字期、大八期字和翻卷期。小八字期和翻卷期的花粉附着力之间差异不显著(P>0.05),但花粉萌发率之间存在较大差异。(2)核桃不同授粉方式下,花粉在柱头上的萌发时间格局、花粉管生长延伸完成受精的时间格局存在极显著差异(P<0.01)。花粉在柱头上8~36 h完成萌发,其中人工辅助异花授粉所需时间最短(8 h),自然授粉所需时间最长(36h)。授粉后36 h,各授粉方式之间花粉萌发率差异不显著(P>0.05)。核桃花粉从萌发到完成受精至少需要10 d,其中人工辅助异花授粉所需时间最短。在授粉受精过程中,花粉管从柱头穿过引导组织所需时间最长,为76~108 h。授粉后240 h,人工辅助异花授粉花粉管长度占花柱长度的比例极显著高于人工辅助自花授粉(P<0.01),与自然授粉之间差异显著(P<0.05)。【结论】核桃大八字期柱头的花粉附着力最强,且可授性最强,为核桃最佳授粉期。人工辅助异花授粉比自然授粉、人工辅助自花授粉先形成受精核。     

花粉管通道导入外源DNA方法的研究

在总结前人研究的基础上,认为花粉管通道法导入外源DNA的方法可分为花粉粒携带法、子房注射法和柱头切除法。3种导入外源基因的方法已在植物转基因育种研究中被广泛运用。在实际运用中应针对某一特定的受体植物,根据受体植物的雌蕊结构特点选择合适的导入外源基因的方法,可提高花粉管通道法的转化效果和转化率。     

切割花柱方式对亚百系内杂交花粉管生长和结实的影响

用常规柱头授粉和切割不同长度花柱4种授粉方式对亚百系内杂交的花粉管生长和结实情况进行了研究.结果表明:同一系内各组合亲和性存在差异,亲和性较好的组合为"金色号角×多安娜"、"普瑞头×索莱尔",次之为"多安娜×普瑞头","金色号角×普瑞头","普瑞头×多安娜"为不亲和组合;同一系内组合中,采用常规柱头授粉比切割花柱授粉得到胚的比例高,所有组合花粉管均能进入子房,而且随着切割花柱长度的增加,花粉管在花柱中及进入子房的量是依次递减的,种子数目与花粉管的生长情况呈正相关;果实膨大系数不能反映果实是否结籽;所有组合中都存在胚囊不亲和现象,形成了无胚仅有胚乳的种子.     

钙调素对梨自花及异花授粉后花柱自发荧光变化的影响

采用激光共聚焦显微镜研究了外源钙调素及其抗血清对‘丰水’梨自花（不亲和）和异花（亲和）授粉后花柱自发荧光变化的影响。结果表明：授粉12 h后,CaM处理后异花授粉花柱荧光值与未处理异花授粉花柱荧光值相比,花柱上部荧光值降低下部升高;而CaM处理后自花授粉花柱自发荧光值除距柱头2 500～3 000 μm外其余部分均高于未处理自花授粉花柱;CaM抗血清处理后异花授粉花柱荧光值除距柱头1 000～2 000 μm外其余部分均高于未处理异花授粉花柱;CaM抗血清处理自花授粉花柱自发荧光与未处理自花授粉花柱相比,分布规律发生改变,最高值位于距柱头1 000～1 500 μm处。授粉72 h后CaM处理后异花授粉花柱荧光值高于未处理异花授粉花柱,最高值位于子房端;CaM处理后自花授粉与未处理自花授粉花柱自发荧光值相比,分布规律发生改变,最高值位于距柱头1 500～2 000 μm处;CaM抗血清处理后异花及自花授粉花柱自发荧光与未处理异花及自花授粉花柱相比较分布规律均发生了改变,最高值都位于0～500 μm处。证实了外源CaM及其抗血清对自花、异花授粉的生理代谢过程均有影响。     

苹果梨树最佳授粉受精时间观测

苹果梨是自花不结实品种。苹果梨在开花后5d（天）内均有很高的授粉能力，其中，花后2－5d（天）坐果率最高，花朵坐昆率为90.0%－96.7%，花后第6d（天）授粉能力开始降低，第7d（天）花朵坐果率已降至10.0%，第8d（天）失去授粉能力。苹果梨授粉10h（小时）后花粉管开始进入花柱，24h（小时）后花粉管大部分已进入花柱，48h（小时）到达子房中部，56h（小时）后开始进入子房，96h（小时）绝大部分花粉管到达子房完成受精过程。     

甘蓝与萝卜属间杂交及其胚挽救技术优化

以甘蓝显性雄性不育系C08-11为母本,以萝卜自交系Q07-12为父本进行属间杂交,对杂交子房和胚珠进行离体培养,筛选适合甘蓝与萝卜属间杂种胚挽救的适宜取材时间、培养基及外源添加物。结果表明,胚珠培养优于子房培养;所有处理子房培养仅获得3株杂交苗,取材时间以授粉后第9天为宜,B5培养基中添加合适的生长调节剂、水解酪蛋白和活性炭为子房培养所必需;胚珠培养各处理共获得29株杂交苗,适宜取材时间为蕾期授粉后第14天、花期授粉后第16天,对生长调节剂的需求取决于不同取材时期及培养基。     

马蔺与溪荪种间杂交亲和性研究

 以鸢尾属植物马蔺（Iris lactea Pall. var. chinensis Koidz.）和溪荪（Iris sanguinea Hormen.）为试材,对常规授粉后结实性及花粉管的行为进行了观察,并研究不同授粉方式对马蔺和溪荪正反交结实率的影响,探讨了其种间杂交的亲和性。结果表明：马蔺与溪荪杂交表现不亲和性,常规授粉正反交结实率均为0;常规授粉2 h后,溪荪的花粉在马蔺的柱头上能萌发,但花粉粒萌发和花粉管的伸长较两亲本自交滞后,柱头和通道内胼胝质现象明显;马蔺的花粉在溪荪的柱头上不能萌发。几种不同授粉方式处理中,马蔺 × 溪荪组合最适授粉方式为0.1% 6-BA处理柱头后授粉,结实率和有胚率分别为10%和16.67%。溪荪 × 马蔺组合的最适授粉方式为提前授粉,结实率和有胚率分别为15%和25.70%。     

草莓果实外源基因瞬时表达系统的建立

将东北红豆杉紫杉烷13α-羟基化酶(Taxane13α-hydroxylase,13OH)基因全长cDNA正向插入到pCAMBI-A1304,构建其植物表达载体pCT13OH;将水稻小RNA169d(microRNA169d,miRNA169d)基因前体(precursor)全长DNA正向插入到pCAMBIA1305.1,构建其植物表达载体pCO169d。用电击法把它们导入根癌农杆菌GV3101,获得有关工程菌株。用1mL无菌注射器分别将这2种工程农杆菌悬浮液注射到草莓(Fragaria×ananassa)授粉后1周、2周、3周的果实中,发现授粉后2周果实适宜注射,可用于瞬时表达。对授粉后2周的果实进行不同注射部位、根癌农杆菌不同活化时期和根癌农杆菌悬浮液不同注射量试验,以蒂部注射、根癌农杆菌活化12h和0.5mL悬浮液注射量的效果最好,与结构基因13OH和调节基因miRNA169d相融合的GUS基因都得到表达,瞬时表达成功。     

上海地区栽培的欧洲甜樱桃花器发育的观察

 为了探讨上海地区甜樱桃结实不良的原因，以5年生欧洲甜樱桃(Prunus avium L．)为试验 材料，就其花器发育状况进行了探讨。结果表明，上海地区生长的甜樱桃花芽形成良好，雌蕊、雄蕊外观形态无异常。花粉粒形态正常，发芽率达50％左右，但有98．2％的子房发育不正常，其中无胚珠分化的子房占26．3％ ，有胚珠而无胚囊分化的子房占71．9％ 。胚珠、胚囊发育不良是上海甜樱桃不能正常结实的主要原因。     

Effective pollination period in durian (Durio zibethinus Murr.) and the factors regulating it

The effective pollination period (EPP) of durian was determined by both delayed and bud pollination, during which reproductive factors affecting the EPP, e.g., stigma receptivity, pollen tube growth in the style, and ovule longevity were studied histologically. This study was conducted in three distinct locations in Thailand, namely, the Chantaburi Horticultural Research Center and two private orchards in Chantaburi and Trat provinces. Results from artificial pollination revealed that at anthesis, the durian flower is receptive and has a high fruit set ratio. A mean fruit set of 50% was obtained at anthesis in the private orchard in Chantaburi province. However, the EPP of durian was found to be very short, lasting for only one night; the fruit set from pollination on the morning after anthesis ranged from 0% to 3.4%. No fruit set occurred following pollination 24 or more hours after anthesis. When compared with the flowers of other fruit species, the durian flower has a unique feature in that it blooms overnight; the following morning, there is abscission of all parts of the flower, except the gynoecium. Thus, EPP appears to be synchronized with flower longevity. On the other hand, the durian flower was receptive several hours before anthesis. The results of chemical tests, including the hydrogen peroxide test and Perex-Test^®, for the evaluation of stigma receptivity appeared to be in agreement with the EPP. However, fluorescent microscopy revealed that pollen could germinate even in the stigmas pollinated 48 h after anthesis, but the number of pollen tubes at the top of the style rapidly decreased from 34.6 (at anthesis) to 0.5 (48 h after anthesis). A correlation test demonstrated a higher correlation coefficient between the fruit set and the number of pollen than that between the fruit set and the result of Perex-Test^®. This indicated that pollen tube penetration or elongation in the style was inhibited, probably due to the deterioration of nutritional support from the pistil to the pollen tubes; this can be a limiting factor of the EPP in durian.     

槜李雌蕊形态及早期胚胎发育研究

采用常规石蜡切片法对槜李雌蕊形态和早期胚胎发生发育进行了研究,以期从生殖生物学角度探讨影响槜李低产的原因。结果表明,槜李花柱实心,子房1室,横生胚珠,双珠被,厚珠心。雌蕊胚囊在盛花时仍处在2～4核期。观察的材料中,绝大部分胚囊在盛花后3d发育为成熟胚囊,胚囊蓼型。合子约休眠2～3d后开始分裂。胚乳在盛花7d后出现,八分体原胚出现在第12天。胚胎发生发育过程中有珠心珠被退化、成熟胚囊结构异常等现象。     

葡萄新品种‘碧香无核’

 ‘碧香无核’是以‘1851’ב莎巴珍珠’育成的极早熟无核新品种。平均单穗质量600ｇ,平均单粒质量4ｇ,可溶性固形物含量22%～28%。具浓郁的玫瑰香味,甜,品质佳;果皮黄绿色,肉脆可切片;早花早果,连续坐果能力强。     

Pollen-tube growth behaviour in ‘Chanee’ and ‘Monthong’ durians (Durio zibethinus L.) after selfing and reciprocal crossing

Summary

Two durian cultivars, ‘Monthong’ and ‘Chanee’, were investigated with respect to post-pollination processes in the pistil and the percentages of fruit set after self-pollination or reciprocal crossing. Pollen grains from each cultivar germinated normally on both stigmas and grew downwards healthily. The percentage of penetrated ovules exceeded 40% in all treatments. However, fruit set after self-pollination in ‘Chanee’ was extremely low. The percentage of fruit set in ‘Chanee’ 35 d after self-pollination (DAP) was 0% in 2002 and 2003, while that of ‘Monthong’ was 6.9% in 2002, and 23.6% in 2003. The percentage of fruit-set after cross-pollination was significantly higher. On the basis of pollen-tube growth behaviour and the non-synchronisation of fruit drop between self-pollination and the two cross combinations, it may be that ‘Monthong’ and ‘Chanee’ durians possess post-zygotic barriers to selfing, especially in ‘Chanee.’     

Flower morphology and number of aubergine (Solanum melongena L.) in relation to fruit load and auxin application

The effect of fruit load and auxin application on the flower morphology and flower number of two aubergine cultivars was investigated under greenhouse conditions. The flowers of plants that did not set fruit showed only minor fluctuations in flower and pistil mass, and in style and anther length. However, when plants were allowed to set fruit by pollination, flower and pistil mass, and style (but not anther) length were significantly reduced during the stage of fruit growth. Style length was also reduced in flowers formed after fruit had been set parthenocarpically by the application of auxin (IAA), but there was no significant effect of IAA on style length in the absence of fruit development. The number of flowers was reduced in the presence of IAA (with or without fruit set), or following fruit set by pollination. It is suggested that fruit load and development affect flower mass and style length of aubergine whereas auxin influences the number of flowers.     

白花山碧桃雌蕊败育特性的解剖学研究

采用石蜡切片的方法,对雌蕊完全败育的白花山碧桃和雌蕊发育正常的满天红进行解剖学观察,发现白花山碧桃在进入自然休眠前,花芽形态分化完成,并且未见异常;此后,白花山碧桃的雌蕊发育滞缓,表现为胚珠原基发育停滞、子房室不再膨大、花柱基本不伸长和柱头表面异常。从而可以确定白花山碧桃雌蕊败育的主要原因是胚珠败育,其败育的起始时期为性细胞分化初期。     

Self-fertilization in homozygous and heterozygous self-compatible almonds

In homozygous self-compatible genotypes 100% of the pollen grains are potentially able to grow through their own pistil, and thus the rate of self-fertilization could be higher than in heterozygous self-compatible genotypes. To evaluate the advantages of growing homozygous self-compatible almonds, pollen tube growth along the pistil at different times following self-pollination, and fruit set were studied in four homozygous and four heterozygous self-compatible seedlings. The results showed important differences between homozygous and heterozygous individuals for the percentages of pollen tubes in the third section of the style at 24 and 48 h, the pollen tube growth rate being higher in the homozygous. Twenty-four hours following self-pollination only the homozygous individuals showed pollen tubes in the ovary. However, at 72 and 96 h those values were similar for both genotypes, suggesting that space and availability of nutrients become the main limiting factors, overcoming the genetic interactions between pollen and pistil. In general, fruit set was similar in homozygous and heterozygous individuals. Interestingly, one of the homozygous individuals showed problems of fruit development, which might be explained by its inbred origin.     

早熟杏新品种‘金凯特’

 ‘金凯特’杏是从‘凯特’杏的自然杂交实生种中选出的早熟优良新品种。果实卵圆形，平均单果质量119.0 g；果面金黄色，光洁美观；果肉橘黄色，肉质细脆，汁液多，风味酸甜可口，香气浓郁，可溶性固形物含量14.0%。具有早熟、大果、优质、高产、耐贮运、自花结实、雌蕊败育率低及早果性强等特点。     

湖南报春苣苔的花部特征及其繁育系统研究

为揭示湖南报春苣苔（Primulina hunanensis）花部特征和繁育系统对有性繁殖过程的影响，合理开发利用其野生种质资源，对其开花物候、花部特征以及访花昆虫类型进行了野外定点观测，测量和分析了花粉活力及柱头可授性、花粉胚珠比值、杂交指数，并结合人工辅助授粉试验对其繁育系统进行了检测。结果表明，（1）湖南报春苣苔花期在 5—7 月，长约 40 d，单花周期 3 ? 8 d；雌雄异熟，开放当天花粉活力最强（> 90%），柱头无活性；雌雄异位，开放后雄蕊几乎不再生长，而雌蕊继续伸长。（2）花粉胚珠比值为 518.36，杂交指数为 5，繁育系统以异交为主，部分自交亲和，需要传粉者；去雄不授粉套袋结实率为 0，不存在无融合生殖。（3）开花期间存在多种传粉者，熊蜂与其花部特征相适应，为最有效传粉者。（4）自然状态下结实率较高；存在无性繁殖，作为生殖补偿机制维持种群的数量。