壁蜂与蜜蜂对棉花胞质雄性不育系的传粉特性比较

为了筛选适用于棉花胞质雄性不育系授粉的蜂种,2013―2014年以蜜蜂为对照,在网室内进行壁蜂对棉花胞质雄性不育系授粉试验,观察壁蜂和蜜蜂在棉花花朵上的生物学特性,并进行田间性状的统计分析。结果表明:壁蜂的适应性较好,受天气影响较小,但温度超过35℃后访花活动明显减少;壁蜂在不育系和保持系上的单花停留时间极显著大于蜜蜂。壁蜂授粉与蜜蜂授粉,在单株结铃数、单铃籽粒数和衣分上差异极显著,单株果枝数、铃重差异显著。蜜蜂授粉较壁蜂授粉平均制种产量高,但壁蜂制种成本低。改进田间管理措施以及采用多次适时释放壁蜂的方式,壁蜂授粉将会在棉花胞质雄性不育系授粉中发挥更大作用。     

凹唇壁蜂的授粉效果研究

凹唇壁蜂在北方苹果、梨、桃、杏、李五大果树品种上释放，可以有效地提高其坐果率，在距放蜂箱８０ｍ以内授粉效果与距离呈负相关，１个壁峰日可以使金冠品种的花朵坐果率在达到７５％，基本可以保证产量。经凹唇壁蜂授粉可以显著提高秦冠、红富士的产量，并能改善其果品质量。     

大白菜亲本繁殖中壁蜂辅助授粉技术

壁蜂属膜翅目、切叶蜂科、壁蜂属,群聚独栖昆虫.一年一代,以卵、幼虫、蛹、成虫在巢管内越夏越冬,出茧率约为80%.大白菜亲本繁殖,可利用壁蜂成虫在巢管外活动的约15～20 d时间放蜂传粉.壁蜂的雌雄比约为1:1.4,以雌蜂进行传粉.壁蜂开始飞翔传粉的气温为12～15℃,一天中以10-16时飞翔传粉最活跃.传粉较好的飞翔距离为40m,一个雌壁蜂是一个蜜蜂(工蜂)传粉能力的80倍左右,应用在大白菜亲本的繁殖上既可以节约成本,又可以提高授粉质量,具有较高的推广利用价值.大白菜亲本繁殖利用壁蜂授粉的主要技术如下:     

不同蜂种授粉对‘金茶1号’茶叶籽传粉效率与果实品质的影响

蜜蜂授粉对农业生产具有非常重要的价值,为了研究不同蜂种授粉对茶叶品质的影响,本研究以茶树‘金茶1号’为研究对象,分别使用意大利蜜蜂(Apis mellifera Ligustica)、中华蜜蜂(Apis cerana cerana)与地熊蜂(Bombus terrestris)开展蜂媒授粉技术及增产提质影响研究。结果表明中蜂授粉组访花频率最高,意蜂授粉组柱头花粉数最高,地熊蜂授粉组单花访问时间最长。中蜂授粉能显著提升茶树的茶叶籽座果率与茶叶籽油茶多酚含量,但对茶叶籽的含油量影响不显著。意蜂授粉与地熊蜂授粉对座果率影响不显,但能显著提升茶叶籽的茶多酚含量与含油量,3个授粉组对茶叶籽油的主要成分并无显著影响。在实际中可以根据生产需要选择对应的蜂种进行授粉。     

壁蜂的行为特性及其在农作物传粉中的应用前景

昆虫传粉对于虫媒农作物生产具有重要作用。壁蜂是近年来得以迅速应用的一种传粉昆虫,通常在早春活动授粉,与蜜蜂相比具有耐低温、访花速率快、授粉效果好、管理简便等特点。中国在利用壁蜂授粉方面起步较晚,但目前研究应用也取得了较大的进展。笔者总结了壁蜂的种类、生活史及授粉特性,阐述了近年来壁蜂在国内外果树授粉中取得的显著经济效益,展望了壁蜂在大田作物授粉中的应用前景,并根据壁蜂的活动规律提出了应用壁蜂授粉需要注意的问题。壁蜂授粉符合虫媒作物生产中经济、高效、环境友好的需求,必将成为现代农业生产中的关键技术。     

不同苹果产区壁蜂授粉生物学特性及授粉效应研究

为了解决苹果座果率低、品质不高的问题,以不同苹果产区的苹果树为试验材料,采用田间试验的方法对不同苹果产区壁蜂授粉生物学特性及授粉效应进行了研究。结果表明：壁蜂始飞温度低（10-11℃）,日工作时间长（10h）,日访花数量多（4200朵）,授粉能力强,访花一次授粉率高达40%。壁蜂授粉的有效距离为60m;壁蜂授粉有方位选择性,西边和南边向阳果树座果率明显大于北边和东边;壁蜂授粉的果个、单果重比对照都有所增加,壁蜂授粉增加了果园产量,平均增产7012.5 kg/ hm2,同时,壁蜂授粉能够提高果品品质,增加苹果的商品价值,壁蜂授粉处理园的果实品质各指标均大于对照园。投放巢管口颜色以红色营巢回收比例最高,营巢比例苇管最高,其次是纸管,最后是塑料管。     

壁蜂在大白菜亲本繁殖中的授粉技术

壁蜂属膜翅目、切叶蜂科、壁蜂属，群聚独栖昆虫。1年1代，以卵、幼虫、蛹、成虫在巢管内越夏越冬，出茧率约为80％。大白菜亲本繁殖中，可利用壁蜂成虫在巢管外活动约15～20d的时间放蜂传粉。壁蜂的雌雄比约为1．0：1．4，以雌蜂进行传粉；壁蜂开始飞翔传粉的气温为12～15℃，以10：00～16：00飞翔传粉最活跃；     

寄主密度对烟蚜茧蜂生殖特性的影响

以麦长管蚜为寄主，研究了不同寄主密度下烟蚜茧蜂的产卵量、寄生蚜量，并组建了不同寄主密度下的烟蚜茧蜂的生殖力表。结果表明：在寄主密度低于４０头蚜／天／雌蜂，烟蚜茧蜂的产卵量随寄主密度的增加而增加，蚜虫的供应限制了该蜂的产卵量；寄主密度高于４０头蚜／天／雌蜂时，烟蚜茧蜂的产卵量为４９３．３～５８７．５粒。烟蚜茧蜂的寄生蚜量亦随寄主密度的增加而增加，在寄主密度１００头蚜／天／雌蜂，可达到３５２．５头。该蜂的内禀增长率则随寄主密度和寄生蜂的性比的变化而变化，在寄主密度１００头蚜／天／雌蜂，寄生蜂性比０．６（♀／）下，可达到０．３３１     

烟蚜茧蜂,菜蚜茧蜂各个虫态及世代发育起点和有效积温的研究

通过解剖，观察、记录烟蚜茧蜂与菜蚜茧蜂各个虫态，接蜂至形成僵蚜和接蜂到出峰的发育历期，依据有效积温法则，计算出两种蚜蜂各虫态及世代发育起点的有效积温，由此推算出在北京地区烟蚜茧蜂常年平均发生１７代，最多１９代，菜蚜茧蜂平均１７代，最多１８代，最少１６代。     

杂交稻制种人工辅助授粉工具选择与应用研究

杂交水稻制种人工辅助授粉，采用双型授粉竿定期定位定操作进行授粉，母本穗层的花粉分布密度较为均匀，提高了及时花粉与非及时花粉的有效利用率，异交结实率比现有人工辅助授粉有明显提高。     

棉花诱导长柱头杂交制种及配套技术研究

旨在减少棉花杂交制种用工,提高棉花杂交制种工效,降低棉花杂交种子生产成本。采用GA₃溶液诱导棉花长柱头,不去雄直接授粉;采用小型强磁高速电动机作为动力,研制小型田间快速采粉器,同时研制与采粉器配套使用的简易授粉器。通过多年的研究,研制出一种新的杂交棉制种新方法,即用100 mg/kg浓度的GA₃溶液,处理8~18天母本的幼蕾,每花点滴量150~200 μL,开花当天,不去雄父本花粉直接授予母本伸长的柱头上;研制出与之相配套的棉花快速采粉器和低温贮能式授粉器,操作简便,田间采粉速度快,授粉效率高,生产的杂交种子纯度在95%以上,符合国家良种要求。该研究将稳定的诱导技术与采粉器和授粉器结合应用于棉花杂交制种,可节省大量用工,综合提高制种工效30%以上。     

授粉品种对砀山酥梨坐果及果实萼片宿存的影响

为明确砀山酥梨较高的坐果花朵序位和脱萼率高的授粉品种,以12个不同梨品种为授粉品种,通过田间试验,研究了不同品种授粉对砀山酥梨不同花朵序位坐果率、花萼宿存的影响,为砀山酥梨优质高效生产提供技术依据。试验结果表明：不同序位花朵以第3序位坐果率最高;不同方位花朵坐果率无显著差异。不同授粉品种试验结果,红酥脆授粉坐果率最高,达70.30%;紫酥授粉坐果率最低,为25.24%,不同品种授粉坐果率差异达显著水平。不同品种授粉,果实脱萼率以新世纪为最高,黄冠次之,茌梨最低。     

水稻恢复系选育的轮回选择法及其应用效果研究

利用野败型细胞质雄性不育性作为遗传工具,进行水稻恢复系的轮回选择。试验证明：（1）由于构建基础群体时,加入了一定比例具有保持系性质的常规品种,以及在后续世代中,不断将经过后裔测验,证实在主要恢复基因位点上均为杂合型的中选可育株种子返回群体,给不育株授粉,因而保证了每轮次轮回选择群体内不育株比例基本稳     

Haploid induction in potato: Cytological basis for the pollinator effect

Summary A hexaploid endosperm is regularly associated with a haploid embryo following 4x–2x crosses in potato. One explanation for this is that a single 24-chromosome restitution sperm nucleus fuses with the central cell of the megagametophyte. This suggests that a superior pollinator may be one that produces a high frequency of restitution sperm nuclei. To test this, a technique was developed for observing pollen tube mitosis in vitro following germination of potato pollen in a 20% lactose-50 ppm boric acid solution. A single 24-chromosome restitution sperm nucleus was found in up to 38% of the pollen tubes from a superior pollinator. Moreover, pollen from an inferior pollinator soaked in a sucrose-boric acid-colchicine solution produced 100% restitution sperm nuclei in vitro and a haploid frequency from a tetraploid cultivar comparable to that normally induced by an untreated superior pollinator. The data indicate that the effectiveness of a pollinator in inducing haploids in potato is determined by the frequency of restitution sperm nuclei it produces.Cooperative investigations of the Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture, and the Wisconsin Agricultural Experiment Station. Part of a thesis submitted by the senior author in partial fulfilment of the requirements for the Ph. D. degree. Published with the approval of the Director of the Wisconsin Agricultural Experiment Station.Research Assistant, Department of Horticulture, University of Wisconsin, and Research Geneticist, Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture, Madison, Wisconsin 53706.     

Performance of pearl millet isonuclear hybrids involving different cytoplasmic male-sterility systems

The performance of pearl millet hybrids involving four sources of cytoplasmic male sterility (CMS), including the most-exploited A₁ source, was compared to evaluate the effects of cytoplasm on grain yield. The mean grain yield of hybrids possessing A₂, A₃ and A₄ cytoplasms was either similar to or significantly higher than that of their counterpart hybrids with A₁ cytoplasm. Hybrids based on A₃ and A₄ cytoplasms produced, on average, 8% more grain compared with those based on A₁ cytoplasm. This suggested that these CMS sources could be used as alternatives to A₁ cytoplasm to widen the cytoplasmic base of hybrids. The results indicated that most of the variation in hybrids was accounted for by pollinator and cytoplasm × pollinator interactions, suggesting the use of genetically diverse pollinators in pearl millet hybrid breeding.     

Analysis of dihaploid induction and production ability and seed parent x pollinator interaction in potato

Summary The production of dihaploids is the first step in a potato breeding program at the diploid level. Dihaploid induction ability, dihaploid production ability and seed parent x pollinator interaction were analyzed for 28 × 3, seed parent x pollinator combinations. This is the first report on significant interaction between seed parents and pollinators. Despite this interaction, IVP 101 had a significantly higher dihaploid induction ability than the widely used pollinators IVP 35 and IVP 48. Previous findings on significant differences in dihaploid production ability between seed parents were clearly confirmed.     

Some aspects of cross-pollination in wheat (Triticum aestivum L.). 4. Seed set on male sterile plants as influenced by distance from the pollen source,pollinator: Male sterile ratio and width of the male sterile strip

Summary The literature dealing with seed set on male sterile wheat plants by open pollination is critically reviewed with special attention to the influence of the distance from the pollen source and the pollinator: male sterile ratio. It is suggested to indicate seed set only as a percentage of the fertile analogue.Own investigations in Wageningen, the Netherlands, indicated that seed set on male sterile wheat plants on various distances from a pollen source of 6×6 m of a mixture of three spring wheat varieties amounted to maximally about 36%, but decreased quickly at increasing distances. Apart from an evident effect of the wind direction, in 1968 average seed set became less than 10 % after 1 m distance from the pollen source; in 1969 and under more favourable experimental conditions for the first meter from the pollen source a decrease to 25% took place, becoming 10% only after 3 m. It is recognized that for practical conclusions the pollen field size applied is too small.Both in 1971 and 1972 the seed set increased with increasing pollinator: male sterile ratio. This increase always was relatively small and, consequently, the kg yield hybrid seed per ha to be expected always decreased when this ratio increased. Applying a female strip width of 2 m and pollinator (mixture of five spring wheat varieties): male sterile ratios of 1:2, 1:1 and 2:1, in 1971 the latter ratio yielded only 60% of the former. In 1972 the same ratios were tested, but besides three male sterile strip widths were applied: 2, 3 and 4 m. In this year the calculated percentage seed set was much higher than that of the previous years (maximum almost 80%), probably as a consequence of more and larger pollinator areas and a more adequate way of establishing the 100% value of seed set. Again the kg yield hybrid seed per ha strongly decreased with an increase of the pollinator: male sterile ratio. The efficiency of the different ratios depends on the width of the female strip. Unfortunately, but according to the expectation, the kg yield hybrid seed per ha decreases, apart from the male to female ratio, fixing the 2 m value at 100%, to about 88% at 3 m and 72% at 4 m female strip width.     

Efficiency of various insects in germplasm regeneration of carrot, onion and turnip rape accessions

Seed regeneration is one of the most important tasks in genebank work. To regenerate germplasm of allogamous, entomophilous plant species in isolation facilities, insects are often used as pollen vectors. The objective of this study was to determine the effect of pollinator species, pollinator densities, pollinator combinations, and flower preferences on the seed quantity and quality of Daucus carota, Allium cepa, and Brassica rapa. The isozyme phosphoglucoisomerase (PGI) served as genetic marker in determining outcrossing rates and pollen dispersal distances. Field plots and isolation cages without insects were used as controls. The pollinators studied consisted of the following insect species from German native fauna: red mason bees (Osmia rufa L.), hoverflies (Eristalis tenax L.), and blowflies (Calliphora sp. and Lucilia sp.). In D. carota and B. rapa, higher seed yields were achieved in isolation cages than in field plots, but in A. cepa lower seed yields were obtained in the isolation cages. Although O. rufa showed no liking for A. cepa, unintentional pollination was effected by this insect in isolation cages. Lower insect densities were necessary for O. rufa than for the various fly species.     

Development of a hybrid variety system in marjoram (Origanum majorana L.)

20 accessions of marjoram (Origanum majorana L.)were characterized in two field experiments in Quedlinburg, Germany in 1997. The variation was assessed both on single plants as a base for the development of pollinator inbred lines of a prospective hybrid variety system and also on plots on a larger scale. The characterization comprised yield of leaf-flower fraction, content of essential oil and its proportion of cis-sabinene hydrate. The anther status of the regrowth after the herb harvest was used as an indicator of male fertility. The investigations revealed a high variability between and within accessions. The correlation of some traits is discussed as a clue to indirect selection. The yield rises with increasing bush diameter of the single plants and with longer vegetation periods caused by late flowering. Relations between the essential oil content and the duration of the vegetation period were not consistent and could be caused by the environment. There were no relations between the anther status and agronomical or physiological traits. This revised version was published online in July 2006 with corrections to the Cover Date.     

Crossability between tritordeum and triticale

Seed set over three years in crosses between three tritordeums used as female parents and four triticale lines, showed that there are significant differences in crossability attributable to both parents and that most of these differences are consistent over the three years. When used as the female parent tritordeum line HT67 had an average seed set of 29.62%, tritordeum line HT9 an average of 12.73%, and tritordeum line HT31 an average of only 6.58% averaged over the four triticales lines used as pollinators. These data show genotype effect that is highly significant (P < 0.001) both for tritordeum and triticale genotypes and highly significant (P < 0.001) female ×year, male × year and female × pollinator interactions. The behaviour of F₁ tritordeum hybrids when crossed with one of the triticale pollinators supports the conclusion that the parents' crossability behaviour is genetically controlled. Analysis of segregation ratio of F₂ hybrids plants from high and low crossability tritordeum genotypes crossed with the same triticale pollinator genotype is consistent with 9:3:3:1 ratio. This revised version was published online in August 2006 with corrections to the Cover Date.