芝麻繁育特性研究Ⅱ:异花传粉媒介的确定

通过人为控制昆虫的活动,对芝麻传粉媒介及其访花行为进行了研究和观察。结果显示,芝麻是自交结实率较高的作物,在没有虫媒的情况下,相对结实率达90.26%;风媒对芝麻异株传粉基本没有作用;小型昆虫有利于芝麻同株或同花传粉,可以提高芝麻相对结实率1.87%,但对异株传粉基本不起作用;大型昆虫对芝麻异株传粉起着极其重要的作用,在自身没有花粉的情况下,昆虫异花传粉可以使芝麻相对结实率高达43.70%;昆虫是芝麻传粉、特别是异花或异株传粉的主要媒介。芝麻传粉昆虫主要以蜜蜂、切叶蜂等为主,访花高峰主要集中在10∶00~13∶30,年份间存在一定差异。     

基因库中多花菜豆种子繁殖更新方法

取材于有特殊经济价值、常异花授粉作物多花菜豆,研究基因库中种子繁殖更新方法。连续３年,选用４个品种,设２５～２００株５种不同群体,采用人工授粉等５种授粉方法,以自然条件下风、虫自然传粉为对照。从农艺性状调查,染色体观察及同工酶分析方面进行研究。人工授粉后无变异现象,但结实率很低,只有２．１％左右,且成本昂贵;群体内昆虫自然传粉结实好,幼苗和籽粒变异率为１．３％和１．２％;单花序或单花套袋自交基本不结实,只有个别品种能结实（１％～２％）;对照生长最好,结实率最高,变异率也最大（幼苗１．７％、籽粒１．９％）;全封闭网棚蜜蜂传粉生长正常,变异率低（幼苗０．４％、籽粒０．７％）,成本也较低;全封闭网棚自然传粉的产量低,折合每公顷只有３７８ｋｇ,其成本高于网棚放蜂者。从而明确了在内蒙古呼和浩特繁种,自然条件适宜可减轻选择压力;以全封闭网棚蜜蜂传粉效果最佳,可减少变异频率,防止外来花粉掺入;其群体大小一般以５０株为宜,是繁殖更新多花菜豆基因库种子切实可行的方法。     

基因库中多花菜豆种子系列更新方法

取材于有特殊经济价值、常异花授粉作物多花菜豆,研究基因库中种子繁殖更新方法,连续３年,选用４个品种,设２５－２００株５种不同群体,采用人工授粉等５种授粉方法,以自然条件下风,虫自然传粉为对照。从农艺性状调查染色体观察及同工酶分析方面进行研究。人工授粉后无变异现象,结实率很低,只有２．１％左右,且成本昂贵,群体内昆虫自然传粉结实好,幼苗和籽粒变异率为１．３％和１．２％;单花序或单花套袋自交基本不结实     

舞草的人工授粉技术

舞草又称跳舞草,由于其小叶具有自身舞动的特异功能,所以深得人们喜爱。舞草开花多而结实少,自然授粉结实率仅为2%～5%,限制了它的传播。笔者近年对舞草进行了人工授粉试验,结果表明结实量是自然授粉的5～10倍,大大增加了种源。现将人工授粉的技术要点介绍于下: 1.花的结构舞草属蝶形花科多年生灌木,其花冠为蝶形,由旗瓣、龙骨瓣和翼瓣组成(依次见图1、2、3)。雄蕊为二体,10个雄蕊有9个花丝连合,1个单生,每个雄蕊由花丝和花药组成,位于花冠的内轮,花丝着     

半夏自交与杂交研究

为解决半夏生产中种茎的退化问题,为半夏的新品种选育及栽培技术提供科学依据。对三叶半夏和掌叶半夏进行自交与杂交,观测并比较其生物学特性、授粉、结实情况及出苗率。结果表明,掌叶半夏、三叶半夏的人工杂交、自交均能结实,但种间杂交表现不育;掌叶半夏与三叶半夏种内杂交结实率分别达65%和60%,平均单株结种子分别为37粒和17粒。掌叶半夏和三叶半夏的自交结实率分别为88.24%和62.5%;半夏自然授粉植株的单株种子数及其种子出苗率都明显高于自交和杂交植株,对异株的花粉有一定的排斥作用。半夏属于同株异花授粉植物,种间杂交不育;其种子不具有休眠特性,应趁鲜播种;半夏有性繁殖可以选育新品种,提高种茎的抗逆能力。     

华北驼绒藜花粉萌发特性及不同授粉方式对其结实率的影响

为寻找华北驼绒藜结实率低、群落退化的原因,在栽培条件下对其花粉生活力、寿命、柱头萌发率与结实率的关系进行了相关性研究。采用同株、异株、自然授粉处理华北驼绒藜,同株授粉结实率(81.53%)显著低于异株授粉(88.6%)和自然授粉(92.6%)的结实率;采用TTC法对华北驼绒藜花粉寿命和生活力的研究结果表明,其平均寿命为6d,最佳授粉时间为1~3d,生活力达95%左右,不存在花粉败育和短命的问题,即不存在小孢子发育障碍。3种授粉方式处理后,采用荧光显微镜观察华北驼绒藜花粉在柱头上的萌发率,萌发高峰集中在授粉后3~4h,萌发率达90%以上,三者不存在显著差异,即华北驼绒藜不存在花粉与柱头的识别障碍。结实率与花粉在柱头萌发率的相关分析结果表明,二者不存在相关性。研究初步认为,同株授粉产生结实率低的原因可能发生在授精或胚胎发育过程,有待进一步研究。目前,华北驼绒藜野生群落严重退化,植被密度减少,可能存在大量自株授粉是造成群落退化的原因之一。     

青海玉树独一味开花特性与传粉方式对传粉效率影响研究

目的:研究独一味在原生地的开花特性与传粉方式对传粉效率的影响.方法:通过对独一味花序开花方式、单花组成及特性、传粉方式及传粉效率、散粉及花粉特性及柱头沉积花粉数的研究,探讨独一味传粉有效方式.结果:独一味花序为轮伞花序密集排列而形成的穗状花序,同一花序中有10％“L”型和90％“S”型2种异型花柱;单花为两性花,花器官由萼片、花冠、雄蕊、雌蕊组成;盛花期的花序中有蚂蚁、熊蜂等昆虫活动,风媒传粉能力弱.结论:独一味传粉效率最高的方式依次为自花传粉,同株自花传粉,异株异花传粉能力较弱.     

香料烟F1杂交种制种效率研究

为解决香料烟生产上利用杂种优势时遇到的制种问题,对授粉环节中有关杂交制种效率的一些主要因素进行了研究,通过在不同开花期设置不同授粉次数和不同授粉时间,调查单株结实情况,结果表明,不同花期授粉对结果率和结实率有不同影响。在授粉杂交的成功率方面,60%的烟株中心花开放后开始杂交,只杂交1次的方法结果率较高,且工资成本较低;40%的中心花开放后开始杂交,杂交3次,每次间隔3~5d的方法平均单株可采收种子量最高,但制种效率低于前者;20%的烟株中心花开放后开始杂交,杂交4次的方法比较费工,制种效率较差。在同一天内的不同时间段进行人工授粉杂交,结果率差异不大,但在16:30~18:30这个时间段授粉,千粒重较高,且蒴果种子量多,平均单株可采收种子量明显增加。因此,选择在40%的烟株中心花开放后开始杂交,杂交2次的方法,不仅提高了花朵利用率,可以获得较高的单株种子产量,而且授粉用工量适中。授粉时间则应选择在16:30~18:30,不仅结实的种子较饱满,而且蒴果种子数量多,单位面积种子产量高。     

花毛茛不同授粉方式与结实量的研究

通过对花毛茛4种不同授粉方式的研究发现:自然授粉下的结实量极显著高于自花授粉和风媒传粉的结实量,而自花授粉与风媒传粉间产量差异不显著;自花授粉与风媒传粉方式下花毛茛的结实数和结实率几乎为0,而相同条件下,风媒传粉和蜜蜂传粉相结合的自然授粉无论是胚囊数目、种子数目、还是优良种子数目都比自花授粉和风媒传粉的明显增加。各品种种子数量的方差分析证明,品种间种子数量存在显著性差异。由T测验看出,4、6号和8号品种的单花胚囊数目、单花种子数目和单花优良种子数目显著比5、7、9号和10号品种多,属于高产类型。     

不同授粉时间对油葵结实率的影响

<正>油用向日葵是异株异花授粉作物,自花授粉结实率很低,必须通过人工辅助授粉才能提高结实率,研究不同授粉时间对油葵结实率大小的影响,对油用向日葵大田制种和生产具有重要的指导作用。油葵田间生产较突出问题是结实率较低,如何提高结实率,是提高产量的关键措施之一。     

Breeding research in sweet potato,Ipomoea batatas poir

In the sweet potato fruit formation following artificial selfing, artifical cross pollination and natural pollination was investigated. Artificial self-pollination in one case gave a fruit formation of 21.2%; in five other cases no or hardly any fruit formation took place. Artificial cross-pollination produced a fruit formation varying from 0 to 52.9%. Natural fertilization did not occur in cases when the nearest flowering sweet potato clone stood at a distance of 80 m. When other flowering clones were in the direct vicinity the percentage of fruit formation through natural pollination differed from 0 to 25.2%.Pre-treatment of sweet potato seed with concentrated sulphuric acid applied during 10 or 20 minutes had a favourable effect on the speed of germination and the germination percentage, also when the seed after treatment was kept in store in or outside an exsiccator for one or two months. The method of scarifying the seed showed a reasonably good influence in this respect. Two different warm water treatments were not or practically not satisfactory.     

逐渐干旱对牡丹光合和荧光特性的影响

（研究目的） 研究逐渐干旱条件下牡丹光合指标及荧光特性变化。（方法）以胡红、洛阳红两种牡丹品种为试验材料,进行土壤逐渐干旱处理,从牡丹光合响应、气体交换、叶绿素荧光参数的变化来研究牡丹光合与荧光特性。（结果）随着土壤水分胁迫的加剧,叶片的净光合速率（Pn）和气孔导度（Gs）下降,胞间CO2浓度（Ci）升高,干旱降低牡丹净光合作用、限制气体交换。（结论）75%的土壤相对含水量最适合牡丹的生长,同时发现与干旱胁迫相比,水分过多更不利牡丹的生长。不同品种间比较发现,胡红比洛阳红更耐旱,适应性更广     

Crossability of American tree peony ‘High Noon’ as seed parent with Japanese cultivars to breed superior cultivars

The tree peony (Paeonia suffruticosa Andr.) is a valuable ornamental plant. American and French cultivars have desirable flower colors, while, Japanese cultivars have larger flowers with better presentation. We hybridized an American tree peony cultivar ‘High Noon (HN)’ (the seed parent) with 57 different Japanese cultivars (pollen parents) to investigate cross compatibility, with the ultimate goal of obtaining improved hybrids. Of the 1,927 crosses performed, 135 (38 cross combinations) yielded a total of 181 seeds (86 mature) and 22 seedlings. Five of the hybrids have already flowered and exhibited their parent character with large yellow flowers. To investigate the causes of cross incompatibility, we examined pollen tube growth in a cross between ‘HN’ and a Japanese cultivar. The result indicated that there are three most important causes of incompatibility, namely, abnormal pollen tube growth, the failure of fertilized ovules, and poor seed germination. Although cross compatibility in each combination was low, crosses between ‘HN’ and Japanese cultivars might be successful with the right paternal plants. In this study, 13 Japanese cultivars had higher cross compatibility with ‘HN’ than the others. Our results will enhance tree peony breeding and guide the selection of parents for hybridization.     

Matromorphy in Brassica oleracea L. VI. Research on ovules,embryos and endosperms after prickle pollination

Summary A research has been carried out on possible differences in developmental rate or growth rate of ovules, embryos and endosperms after prickle pollination and after selfing of Brassica oleracea plants. After prickle pollination ovules, embryos and endosperms developed/grew slower than after selfing which may be attributed to certain disturbances in the embryosac. After prickle pollination embryos and endosperms occurred with possible a rather high ploidy level suggesting that diploid embryosacs were present.     

纳米磁珠介导牡丹花粉转基因技术的初步分析

磁性纳米颗粒(magnetic nanoparticles,MNPs)可以吸附DNA,作为一种新型基因载体应用于转基因育种。本研究旨在探索MNPs介导外源基因进入牡丹花粉,为利用携有外源基因的花粉进行授粉,获得转基因种子提供依据,本研究制备了MNPs与DNA的复合物;利用扫描电子显微镜与透射电子显微镜观察了牡丹花粉的形态结构;用花粉离体萌发法测定了供试牡丹花粉磁转染前后的生活力。结果表明:MNPs与DNA的质量比为1:1~1:10时,MNPs均可以与DNA稳定结合,并可以保护DNA免受酶的消化作用;牡丹花粉为长球形,萌发孔为三孔沟类型,位于萌发沟内;‘凤丹’牡丹、‘京红’牡丹及紫斑牡丹的花粉均具有较高的萌发力,且经磁转染后的三种牡丹花粉萌发力保持在50%以上,能够用于正常杂交授粉。本研究首次采用四氧化三铁纳米磁转化技术介导牡丹花粉转基因,弥补了花粉介导牡丹转基因方法研究的空白,从而有助于牡丹分子育种进程的推进。     

Floral morphology affects seed productivity through pollination efficiency in radish (<Emphasis Type="Italic">Raphanus sativus</Emphasis> L.)

To examine the effect of stigma position and size on seed productivity through pollination efficiency in radish, the numbers of self and cross pollen grains on the stigmas and the seed productivity under insect-pollination were compared among four bred lines. Lines with a small stigma or a high stigma relative to the anthers on long stamens tended to receive fewer self and total (self + cross) pollen grains but showed a higher cross-pollination percentage (ratio of cross pollen grains to total pollen grains on stigmas) than those with a large stigma or a lower stigma. Additionally, a higher cross-pollination percentage was associated with a higher outcrossing percentage. This result suggests that variations in the two stigma traits affect the outcrossing percentage via the cross-pollination percentage. Therefore, it should be possible to prevent loss of F₁ purity by selecting new parental lines with floral morphology that favors cross-pollination percentage.     

油用牡丹经济价值和景观生态价值研究现状

油用牡丹是指结实能力强,能够用来生产种籽、加工食用牡丹油的牡丹类型。是牡丹组植物中产籽出油率高于或等于22%的种的统称。油用牡丹作为我国木本油料作物,具有很高的经济价值、生态价值和社会效益。其牡丹籽油富含不饱和脂肪酸及α-亚麻酸,经济价值显著；牡丹花体积大,单株开花量大,具有很高的观赏价值；油用牡丹具有耐寒、耐旱、耐瘠薄的特点,是荒山绿化的经济树种。主要介绍了我国油用牡丹的研究利用现状、经济价值、景观生态价值及发展前景,为我国推广种植油用牡丹、构建规模化产业体系等方面提供借鉴。     

Short-distance cross-pollination of maize in a small-field landscape as monitored by grain color markers

Results of studies on cross-pollination in small field environments with regard to donor/receptor surface ratios and flower synchrony are scarce. In 2003 and 2004, six field experiments on cross-pollination were carried out in the cantons of Zug and Zurich, two hilly regions of Switzerland. Three (Monopol, Romario and PR39G12) color-dominant yellow-grain maize varieties (Zea mays L.) were planted in close proximity (0.8 m) to color-recessive white-grain maize (DSP17007). The factors of influence were size of the donor and receptor parts of the field and flower synchrony, tested in a tight grid pattern (2.4 m × 10 m; 6000 ears ha⁻¹). Widely varying field size ratios of donors to receptors (about 4:1–1:8) did not influence the cross-pollination rate at distances of 0–20 m from the pollen donor. The synchrony between pollen shedding of the donor and silking of the receptor had a large impact on cross-pollination. In relation to the mid-phase of silk emergence in the receptor field, a temporal isolation of five and seven days resulted in a significant decrease in cross-pollination by more than 80% in comparison to full synchrony. However, in a receptor field with irregular emergence of a number of weak, late-flowering plants led to a remarkable increase in cross-pollination, despite an average temporal separation of 7 days. Marked cross-pollination was restricted to distances up to 15 m; thus, average rates of cross-pollination above 0.9% were easily managed in small fields.     

几种大田栽培牡丹花前光合作用特性初探

利用英国PP-Systems公司生产的CIRAS-1便携式光合作用测定系统对大田栽培的胡红、肉芙蓉、乌龙捧盛和银红巧对四种常用于冬季温室催花牡丹植株光合作用特性进行了研究。结果表明：四种牡丹牡丹植株在大田条件下花前叶片净光合速率Pn的日变化均呈单峰曲线。气孔导度从早上7：00就开始下降。气孔因素是限制牡丹花前净光合速率提高的原因之一。乌龙捧盛有相对较低的光补偿点和光饱和点，具有较强的对较低光强的利用能力，银红巧对具有较高的羧化效率。     

<Emphasis Type="Italic">Epichloë</Emphasis> endophyte and plant genotype determine seed production through self-pollination in tall fescue

Fitness in tall fescue could be determined as the relative seed production by overcoming self-incompatibility barriers. This study was an attempt to investigate the effects of plant genotype and symbiotic fungal endophyte on seed production and associated traits in tall fescue. Fifteen clones of tall fescue free from endophyte and two clones with both endophyte-infected (E+) and non-infected (E?) counterparts were evaluated under two pollination systems of natural open-pollination and obligate self-pollination. Although seed yield was depressed by self-pollination in all E? genotypes, some genotypes exhibited reasonable selfing ratio. However, endophyte infection was much more effective to increase selfing ratio and seed yield through self-pollination particularly in the genotype 75B. Endophyte infection almost removed self-incompatibilty in the host plants and on average resulted in 3.0 times more number of seeds per self-pollinated seedheads than the non-counterpart E? tall fescue genotypes. Although it may need more elaborated studies, incorporating Epichloë fungal endophyte in plant genotypes not only may make the inbreeding in tall fescue possible but also may improve forage yield and seed production, simultaneously.