昆虫授粉对芝麻产量构成因素的影响

为探索芝麻花期访花昆虫授粉效果,更好地利用昆虫为其授粉提高产量。本研究利用全封闭、半封闭、开放3个处理对芝麻花期访花昆虫数量及产量构成因素进行调查和分析。结果表明：蜜蜂是芝麻主要的传粉昆虫,占总访花昆虫数量的78.69%~88.78%。通过芝麻盛花期蜜蜂访花次数可看出,1d当中蜜蜂访花高峰主要集中在9∶00-10∶30和15∶00-16∶30两时段。昆虫授粉可显著增加半封闭区、开放区芝麻单株蒴果数、每蒴粒数、千粒重、单株产量、小区产量,与全封闭区（CK）相比分别提高了7.06%~17.58%、10.48%~16.83%、2.19%~5.13%、11.24%~20.86%、10.12%~20.85%。因此,在芝麻杂交制种和栽培生产过程中,人为增加传粉昆虫数量对提高制种效果和增加芝麻产量具有重要意义。     

苜蓿雄性不育系杂交制种产量性状分析

以回交转育得到8个苜蓿雄性不育株(系)和3个优良苜蓿品种为亲本,分别在开放授粉和人工控制下进行杂交制种试验.结果表明:切叶蜂辅助授粉方式可以有效提高苜蓿雄性不育株(系)的制种产量.综合2种授粉方式下的制种产量,其中2号不育株(系)单株种子产量最高(3.16g/株);通过苜蓿雄性不育株(系)种子产量的相关分析和回归分析,明确了每株生殖枝数对不育株(系)单株种子产量作用影响最大,其次是结实率.     

人工控制条件下大豆不育系昆虫传粉技术研究

在人工控制条件下借助昆虫为大豆不育系传粉是杂交大豆育种的重要手段。试验以不同大豆不育系为材料,在网室、温室以及海南等条件下对蜜蜂、熊蜂和苜蓿切叶蜂的传粉效果进行了研究。结果表明,蜜蜂、熊蜂和苜蓿切叶蜂均可作为大豆不育系的传粉媒介,以苜蓿切叶峰的传粉效率最高。冬季在温室内不宜以昆虫作为传粉媒介繁育不育系。在海南人工加光能够满足大豆正常生长发育的条件下,可以在网室内借助苜蓿切叶峰传粉繁育不育系或生产F1种子。不同基因型大豆不育系间其异交结实程度存在着显著差异。     

放蜂对油菜制种产量质量的影响

放蜂对油菜制种产量质量的影响河南省南阳市种子管理站张学仁，刘杰，鲁红燕，张红霞油菜杂交种以其较强的杂种优势正迅速取代常规品种。目前生产上大面积应用的是甘蓝型胞质类型杂交种，制种时需要借助昆虫和风力等传粉媒介将恢复系花粉授给不育系，以产生杂交种子。许多...     

杂交大豆育种防控技术

大豆杂交种种子繁育程序与常规大豆种子繁育程序有很大差异,与育种程序相关的防控技术也有较多、较高的要求。差异表现在杂交大豆不育系的繁种与杂交种制种要求隔离防控;借助昆虫传粉的杂交种育种,要求做好昆虫传粉防控,防止不育系、杂交种混杂;父、母本要单收单脱,防治混杂;授粉期间病虫害防控等诸多方面。本文总结大豆杂交种育种全生育期的防控技术以指导育种。     

北方染败类型杂交粳稻高产制种机制研究

通过应用3个染败类型粳稻不育系与3个分子辅助选择的恢复系制种机制比较,研究北方杂交梗稻高产制种关键因素之间的关系,包括不育系与恢复系花时动态和不育系柱头亲和力、柱头外露率、张颖面积等特性及其差异。结果表明:不育系与恢复系花时高峰重叠时间对不育系结实率起决定性作用;不育系柱头亲和力、柱头外露率、张颖面积对不育系结实率起关键性作用。大田制种比较9个组合相同行、不同行结实率与制种产量的差异,得出高产制种机制在于制种父母本各因素之间相互协调。综合各研究结果,认为制种关键因素对结实率所起的作用为不育系与恢复系花时高峰重叠时间>不育系柱头亲和力>柱头外露率>不育系张颖面积。本研究为杂交粳稻高产制种在不育系、恢复系的高异交结实特征特性的选育上提供理论基础,为从根本上解决北方杂交梗稻制种产量偏低的问题和北方杂交粳稻稳步发展提供理论依据。     

以半冬性甘蓝型油菜为亲本增强春性甘蓝型油菜杂种优势

以春性恢复系与半冬性品种(系)杂交后选育的16份新春性恢复系及其4个亲本系[2个半冬性甘蓝型油菜品种(系)和2个春性甘蓝型恢复系]、2个春性甘蓝型不育系为材料, 利用SSR、SRAP和AFLP分子标记技术分析材料间的遗传差异, 同时利用以上2个春性不育系分别与12个新春性恢复系和1个春性亲本恢复系Ag-5进行NCII双列杂交, 测定其杂种优势及杂种表现。16份新恢复系中除931和帐23外, 其余的14份新恢复系与2个不育系的遗传距离均大于其春性亲本恢复系与相应不育系的遗传距离, 说明导入半冬性品种遗传成分能扩大春性恢复系与不育系间的遗传差异; 配制的26个杂交组合中, 其双亲中不育系所对应保持系单株产量为高亲值的组合有15个, 其中13个组合单株产量超亲优势都强于所对应不育系与亲本恢复系Ag-5所配杂交组合, 说明导入半冬性品种遗传成分可增强甘蓝型春油菜杂种优势; 12个新恢复系分别与2个不育系所配24个组合中18个组合的单株产量都分别超过所对应不育系与亲本恢复系Ag-5所配杂交组合, 说明导入半冬性品种遗传成分能提高甘蓝型春油菜杂种的产量; 新恢复系与2个不育系杂交后代的抗病性均强于其亲本恢复系与相应不育系杂交后代的抗病性, 说明导入半冬性品种遗传成分能提高春性甘蓝型油菜杂交种抗菌核病的能力。研究结果表明, 半冬性甘蓝型油菜品种可能为春油菜杂交育种提供有价值的遗传资源。     

苜蓿花期访花昆虫种类调查

野生传粉昆虫在提高牧草种子产量方面具有的意义,为了掌握野生访花昆虫的种类及活动规律,指导苜蓿种子生产,笔者于2011年对新疆农业大学呼图壁生态站苜蓿花期访花昆虫种类进行调查研究。结果表明,苜蓿花期访花昆虫有6个目,分属于18个科。其中蜜蜂总科是传粉频率最为稳定的昆虫,也是数量最多的昆虫;6月14—16日是访花昆虫传粉的高峰期,访花昆虫种类及数目最多。一天中,13:00—16:00是访花昆虫传粉活动最频繁的时期。     

棉花蜜蜂传粉杂交制种效果研究

利用抗虫不育系(Btms5ms5ms6ms6)和转Bt基因抗虫棉品系(Rg3)作为杂交制种亲本,制种期间在田间放养蜜蜂作为传粉媒介,连续三年在长江流域和黄河流域进行小规模田间开放式蜜蜂传粉杂交制种试验,对蜜蜂传粉杂交制种体系中的父母本种植比例、不同的蜂种、父母本种植方式、天气等对蜜蜂传粉制种效果进行了研究。初步研究结果表明:父母本种植比例以1:4制种效果较为理想,蜜蜂是较理想的传粉媒介,父母本混合种植方式和相间种植方式传粉效果差异不明显,天气变化对蜜蜂传粉影响较大,直接影响制种产量。     

棉花双隐性核不育系不同授粉方式制种技术试验

通过3年的研究表明,棉花双隐性核不育系利用蜜蜂传粉技术制种,在密度2000株/667m2,父本∶母本为1∶4～1∶6,每667m2放置1～1.5桶意蜂时,种子产量可达50kg/hm2; 与人工授粉相比,昆虫传粉在铃重和每铃种子数上显著较低,而铃重与每铃种子数有很高的正相关,每铃种子数实际又是由杂交花粉量决定,所以提高昆虫传粉的杂交花粉量,从而增加每铃种子数是提高其制种产量的关键;蜜蜂传粉虽然每个工种子产量较高,但在生产实际中应用尚存在困难.在不育系少量保纯繁殖时,或者在成片的棉花制种生产中,蜜蜂传粉制种或者以蜜蜂传粉辅助人工授粉制种是非常可行的方式.     

Ineffectiveness of wrapped flower in inhibiting cross-fertilization in pigeonpea

Summary The wrapped flower character has been reported to inhibit out-crossing in pigeonpea in Australia. However, one of the wrapped flower lines gave an average of about 16% out-crossing at ICRISAT Center near Hyderabad, India. This level of out-crossing was not different from that in cultivars having normal (unwrapped) flowers. This suggests that the wrapped flower trait is not a dependable character for reducing out-crossing in pigeonpea.ICRISAT Journal Article No. 578.     

A comparison of methods for hybrid seed production using self-incompatibility in swedes (Brassica napus ssp. napobrassica)

Procedures for producing seed of hybrid swedes using self-incompatibility were examined. Single-cross, double-cross and modified double-cross hybrids were compared in isolation plots using natural pollinators and in polythene tunnels using blow-flies. With good coincidence of flowering and the same flower colour, nearly 100% hybrid seed was produced by natural pollinators with the single-crosses, the double-cross and one of the two modified double-cross hybrids; the other modified double-cross hybrid produced 87%hybrid seed. With poor coincidence of flowering and different flower colours the proportion of hybrids dropped to 61%. Using different flower colours and blow-flies as pollinators in polythene tunnels, higher levels of outcrossing were produced than in isolation plots with natural pollinators; the opposite result was obtained when the same flower colour was used. This revised version was published online in July 2006 with corrections to the Cover Date.     

木豆不同生长期叶片总黄酮含量研究

为提高木豆叶利用价值,科学合理开发利用木豆叶资源,测试了131份木豆品种现花期木豆叶总黄酮含量及研究不同采收期木豆叶黄酮含量的动态变化规律。通过测定不同生长期木豆叶总黄酮的含量,得知从播种后75天至结荚期,木豆叶总黄酮含量随生长时间的延长而不断增加,呈现明显的累积现象,结荚期的总黄酮含量最高。若以黄酮类化合物作为评价木豆叶药材质量的指标性成分,则可确定黄酮含量高的木豆资源及木豆叶的最佳采收期,此结果为木豆叶的质量评价、选材和采收期的确定提供一定的理论参考。     

Studies on the reproductive biology of white yam (Dioscorea rotundata Poir.)

Summary Investigations were conducted on the identification and distribution of yam natural pollinators, flowering pattern and hybridization of white yam (Dioscorea rotundata Poir.) at the International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria, in order to provide informations for producing hybrid seeds needed for vam genetic improvement.Insects belonging to the Coleoptera (48.0%), Diptera (20.4%), Hymenoptera (20.0%), Hemiptera (5.8%), and Thysanoptera (5.8%) were caught around yam plants and presumed to be pollinators: they entered open-receptive-flowers and their presence on yam plants coincided with the duration of the flowering period.Studies on the flowering pattern revealed that: (i) Male and female clones differed in their periods of flower initiation as well as the flowering duration; (ii) Seed production and conventional breeding methods are feasible if staggered planting, water and soil fertility could be managed to ensure that flowering periods of males and females nick and also extend flowering.Artificial pollinations within white yam and between white yam and yellow yam (D. cayenensis Lam) using the camel hair brush method were successful, but resulted in a relatively low fruit set (31.8% maximum). This method was more effective than natural pollination (19.2%) and can thus supplement it for the production of hybrid seeds for introducing genetic variation in yam breeding populations.     

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。     

梨花和油菜花挥发性气味物质的鉴定及差异分析

为了解花朵中挥发性气味物质对吸引传粉昆虫采集所起到的作用,采用固相微萃取(SPME)和气相色谱-质谱联用(GC-MS)技术,检测梨花和油菜花全花、花药、花蜜中挥发性气味物质成分,并进行主成分及与昆虫采集相关性分析。鉴定梨花中挥发性气味物质成分有9种,氧烷类为主要挥发性气味物质,占44.44%,通过主成分分析,气味贡献物主要来自于二甲基硫醚、十四甲基环七硅氧烷、苯丙腈、苯甲醛等化合物。油菜花中挥发性气味物质成分有23种,酯类和氧烷类为主要气味挥发性物质,分别占8.7%和16.09%,气味贡献物主要来自于反-2-己烯醛、异硫氰酸-2-苯乙酯、4-异硫氰酸根合-1-丁烯、二甲基三硫醚、二甲基二硫醚等化合物;花药的挥发性气味物质种类比花蜜中更丰富。传粉昆虫调查发现,试验地共有传粉昆虫4目10科11种,梨和油菜传粉昆虫数量上有显著差异(P<0.05),但各成分与采集昆虫数量均没有显著相关性(P>0.05)。研究发现梨花和油菜花挥发性气味物质成分有显著差异,将为研究气味物质主要贡献物在吸引传粉昆虫中发挥的作用提供参考。     

Is bigger better? Apidae (Xylocopinae), megachilidae and cowpea (Vigna unguiculata) pollination

Cowpea is an important grain legume crop in Africa. Cowpea flowers are capable of self-fertilization, which might be the most frequent type of reproduction. Nevertheless, the rate of cross-pollination could vary between 1% and 10%, depending on the populations of bumblebees or domestic bees that are present, the climate and the cultivar. The aim of this study was to identify and assess the efficiency rate of the pollinators of the wild cowpea, Vigna unguiculata subsp. unguiculata var. spontanea, the progenitor of the domesticated cowpea Vigna unguiculata subsp. unguiculata. Pollination study was conducted by observing patches of flowers (average 10–20/m²) from dawn to midday, approximately 05:00–12:30 hr for three years. All insects visiting the flowers were noted and identified to species level, where possible, and their foraging behaviour was monitored. Pollen grain deposit and pod set were estimated using single bee visits on plants with strictly outcrossing flowers. Major flower visitors were large bees of the family Megachilidae and the genus Xylocopa (Apidae, Xylocopinae). Xylocopa caffra (Linnaeus) was the most abundant bee species, accounting for 59% of total bees observed and 58% of total flower visited. Pod set was higher in visits by megachilid bees compared to Xylocopa bees. Within Xylocopa, there is a good correlation between size and efficiency (r = .95, p = .0477), the larger insects being more efficient. Honeybees, small bees (Ceratina and Nomia species) and Lepidopterans also visited flowers but without any effect on pollination. Cowpea pollination system is specialized, and pollinators are restricted to Megachilidae and Xylocopa species. Variation in pollen load deposit and pod set reveals that pollination success depends on the insect species involved and their size. Megachilids are the most efficient pollinators, especially since they are able to promote outcrossing more efficiently than Xylocopa species.     

Highly variable ‘Arhar’ simple sequence repeat markers for molecular diversity and phylogenetic studies in pigeonpea [Cajanus cajan (L.) Millisp.]

Pigeonpea is an important tropical grain legume widely cultivated in South and South‐East Asia for versatile end usage as food, feed, fodder and fuel. Recent publication of draft genome sequence of pigeonpea (‘Arhar’) has allowed mining of large numbers of genomic simple sequence repeat (SSR) markers most of which are either not validated or show very little polymorphism in simple agarose gel–based assays. Here, we describe a special category of 370 validated highly variable ‘Arhar’ genomic SSR (HASSR) markers, which provide much higher level of polymorphism than a random set of SSR markers. These markers were validated for consistent amplification in a set of eight pigeonpea varieties and 152 of these (41%) showed allelic polymorphism on agarose gel electrophoresis. Twenty‐four highest polymorphic HASSR markers were used on a larger set of forty pigeonpea varieties and eight wild Cajanus species for the analysis of genetic diversity and phylogenetic relationship. Genomic HASSR markers described here are highly suitable for genetic diversity and phylogenic studies in pigeonpea.     

Variation in floral scent compounds recognized by honeybees in Brassicaceae crop species

Floral scent attracts pollinators. We investigated the floral scent compounds recognized by pollinators in six Brassica crop species, including allogamous species with different genomes and autogamous species with two parental genomes and radish (Raphanus sativus). Biologically active compounds recognized by honeybees were screened from all floral compounds by combined gas chromatography–electroantennogram analysis and their profiles were determined by gas chromatography–mass spectrometry. Fourteen of the 52 compounds were active. All accessions had more than two active compounds, but the compounds greatly differed between the two genera. On the basis of similarities in whether active compounds were presence or absence, their amount and their composition ratio, we divided the Brassica accessions into three to five groups by cluster analyses. Most groups were composed of a mixture of allogamous and autogamous species sharing same genome, indicating that the variation depended on genome, not species. These results suggest that all species require pollinator visits for reproduction, despite their different reproductive systems. However, the inter-genus and intra-specific variations shown by the multiple groups within a species might cause different visitation frequencies by pollinators between genera and among accessions within a species, resulting in insufficient seed production in some accessions or species.