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。     

外源多胺对鸭梨自花授粉花粉管生长及自交坐果的影响

以鸭梨为试材,进行不同浓度外源多胺处理,通过离体花粉培养,荧光显微动态观察和花序、花朵坐果率调查,研究了外源多胺处理对鸭梨自花授粉花粉管生长及自交坐果的影响,以期为外源多胺调控鸭梨自交不亲和性提供重要依据。结果表明:适宜浓度的外源腐胺(Put)、亚精胺(Spd)、精胺(Spm)处理后的鸭梨花柱提取液,能够提高花粉萌发率和促进花粉管生长,最适宜的Put浓度和Spd浓度为0.250 mmol·L~(-1),Spm浓度为0.050mmol·L~(-1)。鸭梨自花授粉72h后,花粉管先端膨大,在花柱中部停止生长。3种多胺处理均能使其穿过花柱中部到达基部,其中以0.250mmol·L~(-1) Spd处理花粉管到达基部最多。不同浓度外源多胺均能提高鸭梨自花授粉花序坐果率和花朵坐果率,其中以0.250mmol·L~(-1) Put表现最佳。     

寒富苹果授粉花柱的荧光显微观察与自交亲和性分析

以寒富苹果为试材,进行自花和异花授粉后花朵和花序坐果率、平均种子数调查试验和荧光显微观察,结果表明,寒富苹果自花授粉的花朵坐果率高达92.8%,花序坐果率为98.3%,平均种子数为7.9粒;略低于异花授粉的96.6%、100%和9.5粒。自花授粉8 h后花粉开始萌发,花粉管能够正常生长,48 h花粉管伸入花柱中部,并在72 h后通过花柱基部,进入子房室。而异花授粉后8 h花粉管开始进入花柱,24 h花粉管伸入花柱中部,48 h花粉管穿过花柱的基部并进入子房室。     

花粉管通道法遗传转化核桃的研究

 为了提高核桃花粉管通道法转化成功率，以‘清香’核桃（Juglans regia L.）为试材，研究了外源DNA 导入受体时间、DNA 浓度和导入方法对导入效率的影响。结果表明：外源DNA 滴加处理的适宜时间为授粉后14 ~ 20 h；外源DNA 注射处理的适宜时间为授粉后24 h。综合考虑外源DNA 浓度对坐果率和GUS 检测结果的影响，认为350 ~ 500 μg · mL^-1 DNA 适宜转化。采用切割柱头滴加、柱头直接滴加和子房注射等3 种导入外源DNA 的方法均获得了转化成功的果实，其中以切割柱头滴加法获得的转化果实率最高（36.4%），其次是柱头直接滴加法（20.7%），子房注射法因易造成机械损伤，坐果率最低（10.9%）。     

苹果自花授粉的花粉管结构变化及S-RNase定位

 苹果‘红星’品种授粉处理24 h后, 自花授粉比异花授粉的花粉管生长缓慢。授粉处理48 h后, 可观察到自花授粉花柱通道组织的花粉管内有二裂粒子增加、管壁破裂和管内物质溢出、外层管壁增厚等现象。苹果气球状花期未授粉的花柱及自花和异花授粉24 h后且无花粉管存在的花柱切片显示, S-RNase位于花柱通道组织的细胞内。自花和异花授粉48 h后有花粉管通过的花柱切片显示, S-RNase位于花柱通道组织的细胞间隙和花粉管内。     

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.     

北寨红杏自交不亲和生物学研究

研究了北寨红杏花粉萌发率、有效花率、自交坐果率、自交授粉花粉管在花柱内的生长及分布。结果表明,北寨红杏自花授粉坐果率为0.89%,属自交不亲和品种;花粉萌发率78.63%,有效花率70.91%;自交不亲和使自花授粉的花粉在花柱中生长受到抑制,受抑制时间为授粉后48～72 h(小时),受抑制位置为花柱3/4处。     

果树遗传转化方法概述

综述了果树遗传转化的方法,载体转化系统包括农杆菌质粒载体法和植物病毒载体法;直接转化系统包括化学诱导脱氧核糖核酸直接转化法和物理诱导直接转化法;种质系统介导基因转化系统包括花粉管通道法介导基因转化和生殖细胞浸泡介导遗传转化法。     

常绿杜鹃不同杂种群间杂交的可育性分析

为研究杜鹃花属常绿杜鹃亚属中不同杂种群间杂交的可育性规律,对属于腺柱杜鹃花杂种群(Gr)、云锦杜鹃花杂种群(F)、美国山石南杜鹃花杂种群(Ga)、高加索杜鹃花杂种群(C)和东石楠杜鹃花杂种群(D)的33个品种组配302个杂交组合,对各杂种群间的杂交坐果率、结籽率和种子发芽率进行统计分析;以Ga和F杂种群为父本的杂交组合的花粉萌发率、花粉管长度/花柱长度和胚珠受精率进行荧光显微观察。结果表明:(1)从坐果率考虑,在33个品种中,‘Blurettia’、‘Sun Fire’和‘Surrey Heath’等11个品种适宜作为母本,‘Mrs. P. Denouden’、‘Marcel Menard’和‘Catawbiensis Boursault’等5个品种适宜作为父本,‘Alfred’、‘Delta’和‘XXL’等16个品种作为母本或父本皆可,而‘Cosmopolitan’不适宜作亲本;在5个杂种群中,Gr适宜作为母本,F适宜作为父本,Ga作为母本或者父本皆可,C和D的杂交效果与其配组有关;不同杂种群间杂交存在单向不育、双向可育或不育现象。(2)5个杂种群作为母本杂交的坐果率、结籽率和种子发芽率大小则分别为Ga Gr C D F,Ga CGr D F,Ga C F G r D;作为父本杂交的坐果率、结籽率和种子发芽率大小分别为F Ga GrD C,F Ga D C Gr,F Ga Gr C D;作为亲本的坐果率、结籽率和种子发芽率大小分别为Ga F Gr D C,Ga F D C Gr,F Ga C Gr D。(3)从花粉荧光显微观察结果来看,除D×F的花粉不萌发外,其余组合的花粉均能萌发,但各杂交组合的花粉管长度/花柱长度不同,且胚珠受精率低下。综上所述:常绿杜鹃不同杂种群间杂交存在明显不育现象,包括不能坐果、不能结籽和种子不萌发,而受精前障碍和受精后障碍可能是其杂交不育的关键原因。     

梨不同花龄自花与异花授粉的花柱内花粉管生长及坐果率的比较

对自交不亲和强度不同的梨品种丰水和菊水的不同花龄花进行自花授粉和丰水×菊水异花授粉后,用荧光显微镜观察花粉萌发及生长特性。结果表明,开花当天及以后的自花和异花授粉花粉在柱头上均有较高的萌发率;自花和异花花粉管在花柱内的生长速度及停止生长的位置不同,丰水自花授粉后花粉管生长的短且慢,菊水自花花粉管生长的长且快,而异花授粉的花粉管生长最快。自花授粉后,不同花龄对花粉管生长影响表现为:开花4d前的蕾期授粉以及开花4d后的延迟授粉,花粉管生长长度显著的长。开花6d前的各种授粉组合,花粉管生长均较差。这与田间授粉坐果率的高低基本一致,即整体表现为各个花龄的授粉都以异花授粉坐果率最高,其次为菊水自花授粉,丰水自花授粉坐果率最低。另外,自花授粉中,蕾期授粉和延迟授粉(开花2d后除外)坐果率都有提高,而异花授粉中蕾期授粉和延迟授粉的坐果率却有所下降。     

Observations on the Effect of Potash Supply on the Tension of the Tracheal Contents in Fruit Trees and Bushes

Summary

The effects of pollen source on fruit set and fruit quality characteristics (xenia effects) were examined in three commercial cultivars of mandarin, Imperial, Ellenor, and Murcott. Six trees of each cultivar received six pollination treatments: three cross-pollen sources, self-pollination, bagging and bagging with emasculation. Pollen tube growth, percentage fruit set, fruit weight, seediness, sugar and acid content were assessed in all treatments. Significant xenia effects, including effects on sugar content, were found in all cultivars. `Imperial' was found to be self-incompatible as self-pollen tubes were inhibited in the upper style. This resulted in a lower fruit set in self-pollinated fruits (P<0.01), a very low fruit weight (33–55 g, compared with 92–103 g, P<0.01), and fruits containing few or no seeds. In addition, `Ellenor' and `Murcott' pollen significantly increased sugar content of fruit by between 0.9–1.6% compared with self-pollinated and unpollinated treatments (P<0.05). Widespread problems of variable production and poor fruit quality in `Imperial' may be alleviated by interplanting with appropriate pollen sources such as `Ellenor' and `Murcott'. Pollen source significantly affected fruit set, seed number and sugar content but not fruit weight of cv. Ellenor. In particular, `Murcott' pollen produced a significantly higher fruit set, relatively low seed number, and the highest mean sugar content (13.2%), significantly higher than `Imperial' pollen, bagged, and unpollinated treatments (>12.5%, P<0.01). Fruit production, seediness and sugar content of `Ellenor' mandarin may be improved by interplanting with `Murcott'. Cross-pollination significantly increased seed number of `Murcott' (15–21 seeds per fruit, compared with 13–17 seeds per fruit, P<0.01). `Murcott' could be planted in pure blocks since self-pollinated `Murcott' fruit had slightly fewer seeds than crosses, without any significant loss of size or quality. These results demonstrate the need for careful consideration of interplanting of cultivars and management of pollinators such as the honeybee, Apis mellifera L. to maximize fruit production and quality in mandarins.     

Methods for testing the fertility of tomato pollen formed at low temperature

A reliable indication of pollen fertility is the number of seeds per fruit produced following artificial pollination, but this method is laborious, and very slow because sampling needs ripe fruits. To seek faster techniques to test the fertility of tomato pollen produced at low temperatures, we cultivated a large collection of tomato cultivars and lines of related wild species under cold conditions with minimum nocturnal temperatures below 10°C. We compared numbers of seeds per fruit with: number of pollen tubes at the base of the style, index of natural fruit-set, percentage of pollen grains stained with acetocarmine, percentage of pollen grains giving fluorochromatic reaction with fluoresceine diacetate, and percentage of pollen grains which germinated in vitro. All these variates correlated positively and significantly between themselves. The number of pollen tubes at the base of the style most closely correlated with number of seeds. This technique is equally laborious, but is good for precise testing of small numbers of genotypes and results are quickly available. Both acetocarmine staining and fluorochromatic reaction were simple, fast techniques with potential for screening large collections to detect genotypes with highly fertile pollen at low temperature; acetocarmine was the best, but neither test would identify genotypes with low-fertile pollens. Index of natural fruit-set and germination in vitro did not effectively determine the fertility of pollen produced at low temperature.     

花粉直感对京白梨品质的影响

为研究京白梨生产中花粉直感与所出现的品质退化现象的关系,试验选用11个梨品种为授粉品种,以生长势健壮、结果盛期的京白梨为母本进行人工授粉,测定了不同授粉组合的坐果率、成熟种子数、果实外在品质及内在品质等几个主要指标。结果表明:京白梨果实在坐果率、成熟种子数、单果重、可滴定酸、可溶性固形物等方面表现明显的花粉直感现象,而在果形指数、可食用部分表现不明显。成熟种子数与可滴定酸显著相关,表明花粉可通过种子对果实品质产生一定影响。京白梨最适宜的授粉品种是白梨系统的鸭梨、金水2号、中梨2号和七月酥。     

红籽瓜主要产量性状的遗传力及相关性分析

以红籽瓜农家品种及自交系为供试材料,采用随机区组试验设计,用方差分析法估算了单株坐瓜数、单瓜重、单瓜种子数、单瓜种子重、种仁重、千粒重、出仁率、产籽率和种子体积的广义遗传力;并对43个红籽瓜品种9个产量性状的遗传力、遗传变异系数和相关性进行了研究。结果表明,上述9个产量性状的广义遗传力分别为12.86%,80.14%,75.96%,74.39%,48.01%,17.12%,24.97%,18.60%和37.07%。单瓜重、单瓜种子数和单瓜种子重的遗传力较高,对其进行早世代单株选择有较好的效果;遗传变异系数以千粒重和出仁率较高,选择潜力大。性状间相关性的研究表明:通过对单瓜重的选择,可实现对单瓜种子数、单瓜种子重、种仁重和种子体积等性状的间接选择。并对红籽瓜产量性状遗传力分析结果及其在育种中的应用进行了讨论。     

苹果梨柱头数目对种子和果实发育的影响

选择苹果梨做试材,采用人工切除的方法,花期对苹果梨5个柱头进行了不同数目的缺失柱头试验,调查了坐果率、种子数目及果形指数等.结果表明:1～4柱头处理和对照(5柱头)相比较,在坐果率、种子数目及果形指数上无明显的差异.据此认为,苹果梨花期柱头的缺失并没有影响种子和果实的发育,苹果梨各柱头与每一心室可能是相通的,即某一心室的受精不受某一柱头授粉的影响,只要有一个柱头授粉受精充分,苹果梨就不会因为柱头多少而影响所有种子的形成和果形.     

染色体易位对西瓜主要性状的影响

为了研究染色体易位对西瓜花粉败育率、单瓜种子数及果实品质的影响,通过杂交、回交转育方法,分别得到了具有2对和4对染色体相互易位的纯合品系,并用他们配制了F1代杂合体。结果表明2对染色体相互易位使西瓜花粉败育率达49%,单瓜种子数较双亲平均值减少51%,单瓜重增加5.7%,中心糖提高1.4个百分点。而4对染色体相互易位的杂合体,其花粉败育率超过60%,且单瓜种子数减少75%以上,中心糖和边糖分别提高了0.8%和1.3个百分点。利用4对染色体易位育成的津花四号西瓜新品种与其近等位系京欣一号相比,单瓜种子数减少70%,平均仅有70粒左右,单瓜重增加8.5%,含糖量提高0.5个百分点以上,但早期坐果性不如京欣一号。另外,染色体易位导致西瓜的雄花花瓣和雄蕊变小,瓤质变硬,耐贮运性提高,在西瓜育种及生产上将会有广泛的应用前景。     

The Effect of Distance from Pollinizer Varieties on the Fruit Set on Trees in Plum and Apple Orchards

The fruit set on plum trees decreased greatly with increase in distance from pollinizer trees, and less so with increase in distance from honey-bee colonies. Trees adjacent to pollinizers had a greater set on the sides facing the pollinizers than on their far sides. Parts of trees touching “ bouquets ” had a greater set than parts without bouquets.

In an apple orchard with main variety and pollinizer trees in separate blocks, the fruit set was greater on the main variety trees adjacent to the pollinizers than on trees farther away. In an apple orchard with a pollinizer tree as every third tree in every third row, main variety trees had a greater fruit set, more seeds per fruit, and more carpels with seeds per fruit, on the sides near to their adjacent pollinizers than on their far sides. The fruit set, number of seeds per fruit, and number of carpels with seed per fruit, were greater the nearer the trees were to the adjacent pollinizer.

These results are discussed in relation to the foraging behaviour of honey-bees and to methods of arranging pollinizer and main variety trees in orchards.     

变温处理杂交辣椒种子对其植株生物学性状及果实发育的影响

对杂交辣椒种子经变温处理后对其植株生物学性状及果实发育的影响进行了研究.试验结果表明,变温处理杂交辣椒种子植株株高、株幅、最大叶面积均明显高于对照植株;第1雌花节位较对照降低;单果种子数、单株结果数、单株种子质量、小区种子产量和折667 m2的产量均较对照有所增加.