野生樱桃资源在甜樱桃人工授粉中的应用探讨

以3种野生樱桃资源为供试材料,比较了花粉烘制方式和贮藏温度对供试材料花粉萌芽率的影响,评价了供试材料花粉对甜樱桃品种座果率的影响。结果表明：常温干燥皿烘制花粉萌发率显著高于培养箱烘制;水+10mg/L硼酸+20%蔗糖为测定供试材料花粉活力的适宜培养基;毛樱桃、中国樱桃、‘黄蜜’花粉在4℃冷藏30天的萌发率均高于40%;毛樱桃、中国樱桃和山樱桃花粉与3个甜樱桃品种的异花授粉平均坐果率可达到40%。作者认为,供试野生樱桃资源的花粉萌发和贮藏特性,以及与甜樱桃品种的异花授粉亲和性与供试甜樱桃品种花粉类似,在甜樱桃人工授粉中具有较大的应用价值。     

大豆天然异交率的测定

以控制大豆绿子叶的两个重叠隐性基因(d_1d_2)为标志基因,研究了花粉给体和受体基因型及两者之间的相对距离对大豆天然异交率的影响。花粉受体和给体以10—80厘米距离在行间种植时,大豆天然异交存在显著的受体基因型效应和受体×给体互作效应;距离对大豆天然异交率无显著影响;给体基因型对大豆的天然异交率有显著影响,通交83—932为给体的异交率显著大于以其它基因型为给体的异交率。     

异花授粉对柚果实代谢产物的影响及其与内裂的关系

为探究异花授粉对柚果实内裂的影响机制,以琯溪蜜柚为父本、早香柚为母本进行异花授粉,统计种子数与果实内裂的关系,并利用气相色谱-质谱技术(GC-MS)分析果实汁胞代谢物组分.结果表明,早香柚自花授粉果实裂瓣数多为2或3瓣,且裂瓣多处于对称位置,说明果实横向生长拉力是中心柱开裂的直接原因;异花授粉后,果实内裂率与种子数有关...     

苜蓿传粉特性及其制约种子产量形成的因分析

目的豆科牧草苜蓿、小冠花和百脉根异花授粉,胚珠败育现象显著,种子实际产量远低于理论产量,但有关其授粉后的花粉管引导和受精后胚胎发育的基础数据缺乏。方法采用人工授粉方法,对3种豆科牧草花粉管引导和胚胎发育进行荧光显微观察,并结合田间数据进行胚珠败育统计分析。结果3种牧草柱头授粉最佳时期为花药开裂阶段,柱头角质层是其花粉管穿入花柱的机械屏障;苜蓿授粉2 h后花粉萌发,8 h后花粉管生长并到达胚珠,24 h后75%的胚珠处有花粉管到达;小冠花和百脉根花粉管萌发生长到达胚珠的时间比苜蓿快,授粉4 h后即观察到花粉管生长到达胚珠,8 h后2种牧草96%和100%的胚珠处均有花粉管分布。进一步的荚果结实观察发现：苜蓿、小冠花和百脉根授粉后胚珠败育严重,平均败育率分别为87.67%、78.00%和81.33%,荚果内败育胚珠的位置具有随机性。以上结果表明：授粉后不同牧草花粉萌发和花粉管生长速率明显不同,尽管小冠花和百脉根的花柱比苜蓿长,其花粉管生长引导速度比苜蓿快;从到达胚珠的花粉管数量来看,3种牧草花粉数量均可满足其胚珠受精需要。结论3种豆科牧草胚珠败育并非由于受精前的花粉萌发和花粉管引导限制,而是和受精后的胚胎发育受阻有关。     

沙梨花粉原位萌发与花粉管生长特性

用荧光显微镜对自交不亲和强度不同的梨品种丰水和菊水自花授粉及以丰水为母本的异花授粉后的花粉萌发及花粉管生长特性进行观察。结果表明，自花与异花花粉在柱头上均有较高的萌发率，高达95％以上，且二间没有显的差异。自花与异花花粉管在花柱内的生长速度及停止生长的位置不同，丰水自花花粉管生长到花柱1／3处就完全停止生长，表现为强自交不亲和性，而菊水自花花粉管大部分也在花柱1／3处停止生长，但仍有少量长至花柱基部，表现为弱自交不亲和性；而异花授粉的花粉管虽然在花柱内也有停止生长现象，但大量的花粉管能长到花柱基部，表现为杂交亲和性。花柱内自花授粉的花粉管在停止生长之前有弯曲、先端膨大变形等现象，而异花授粉的花粉管没有此现象。     

Pollen sterility induced by ethrel and its utilization in hybridization of wheat

Summary In 1974 and 1975 gametocidal effects of Ethrel were investigated under field conditions in the spring wheat cv. Zlatka. In experimental plants grain setting per spikelet and ear as well as ability to be cross-pollinated were ascertained.As compared with the control, treated variants achieved more than 90% sterility. Female fertility was not affected and cross-pollination was possible. Genetical check showed that the best variants, when cross-pollinated, produced 50–55% hybrids; grain setting, however, was brought down by more than 37%. As a result of Ethrel treatment haulm length was reduced and the vegetation period was somewhat prolonged.     

Pollination effects on fruit production of ‘Star Ruby’ grapefruit (Citrus paradisi Macf.)

Flowers of ‘Star Ruby’ grapefruit were hand-pollinated with ‘Valencia’ orange (C. sinensis (L.) Osbeck), ‘Marrs’ orange, ‘Ruby Red’ grapefruit (C. paradisi Macf.) and ‘Star Ruby’ grapefruit pollen. Flowers cross-pollinated with ‘Ruby Red’ pollen produced more fruit than did self-pollinated flowers. Flowers cross-pollinated with either ‘Marrs’ or ‘Valencia’ pollen did not produce as many fruit as ‘Ruby Red’-pollinated flowers, nor did they produce more fruit than self-pollinated or open-pollinated flowers. Few fruit were produced when ‘Star Ruby’ flowers were not hand-pollinated. Less than 0.5% of ‘Star Ruby’ pollen germinated in 15–25% sucrose solutions, whereas between 6 and 21% of the pollen from ‘Valencia’, ‘Marrs’ and ‘Ruby Red’ germinated. The number of fully-developed seeds per fruit was increased only when ‘Marrs’ pollen was used. These data show that ‘Star Ruby’ produces very little functional pollen and few functional ovules, and suggests that ‘Star Ruby’ has weak parthenocarpic ability.     

Flatpea crossing methods and germplasm screening for reduced 2,4-diaminobutyric acid composition

Summary Flatpea (Lathyrus sylvestris L.) is a potentially valuable forage legume, but it contains high levels of 2,4-diaminobutyric acid (A₂bu), a compound that can have adverse effects on some animals, including rats and poultry. This study evaluated intercrossed pollination methodology needed for cultivar improvement and characterized intercrossed progeny for A₂bu concentration. Pollen germination on an artificial medium, using pollen collected during different stages of flower development, was used to identify appropriate stages for flower emasculation. Pollen dehiscence occurred at an early-bud stage when petal color was first evident. Slightly more mature buds contained pollen with substantially higher in vitro germination than pollen from early-bud stage flowers. Lines that produced high numbers of seeds per pollination were identified from crosses between flatpea accessions. Cross-pollination resulted in significantly higher seed set than selfing. Pollination using caged honeybees was the most efficient method of hybridization, although the degree of inbreeding in bee-pollinated plants could not be determined. Intercrossed progeny produced by honeybee pollination contained a lower mean concentration of foliar A₂bu than the mean for flatpea accessions.Abbreviations HPLC high performance liquid chromatography - OPA ortho-phthalaldehyde     

不同授粉次数和环境条件对金盏花结实率的影响

在春秋大棚进行金盏花杂交授粉试验,探讨不同授粉次数和环境条件对金盏花结实率的影响。结果表明,实施2次和3次授粉均能获得较高的结实率,其中又以隔天授粉3次的结实率最高;当日均温在21．9—31．7℃之间,每日11：00—16：00的相对湿度维持在37％左右,光照强度在40744～71022lx之间时,可以获得较好的授粉结实率。但气温、湿度和光照强度等环境条件对金盏花结实率的影响幅度仍需进一步研究。