Development of microsatellite markers in sweet passion fruit,and identification of length and conformation polymorphisms within repeat sequences

The aim of this study was to construct and characterize an SSR‐enriched genomic library for Passiflora alata, a fruit species native to the Brazilian plateau and the eastern Amazon region. There is potential to improve this crop, as the fruit is attractive because of its pleasant aroma and flavour characteristics. Of 862 sequences, 391 (45%) were found to have SSRs. We identified 412 microsatellites: 69% were classified as perfect, 23% imperfect, 5% interrupted and 3% were compound microsatellites. The main types of repeat sequences were dinucleotide (62.5%) and trinucleotide (23%) repeats. It was possible to design 312 primer pairs, and 229 of them were synthesized and tested. The amplicons were electrophoresed using denaturing and non‐denaturing gels to screen for divergence between two phenotypically distinct parents of a mapping population of P. alata. Length and conformation polymorphisms within repeat sequences amounted to 35% and 28%, respectively. The importance of the development of SSR markers for sweet passion fruit and the effectiveness of the SSCP approach to increase the available number of polymorphic SSRs are discussed.     

5个新育成粳型光温敏核不育系开花及异交性能的研究

以5个新育成的粳型光温敏核不育系为材料,对其开花习性及异交性能进行了研究。结果表明：Y27S的单穗和单株开花历期最短,118S和对照N5088S相近,B30S、116S、117S相对较长。Y27S、116S、118S、117S单穗日开花动态与恢复系41678接近,B30S落后于41678,对照N5088S早于41678。Y27S、B30S和对照N5088S与恢复系41678的花时分布动态较接近;116S虽花时分散,但开花较早,午前花率较高;117S花时集中但开花较晚,118S花时分散且高峰偏迟。张颖时间以116S和118S最长,117S最短。柱头外露率以118S最高,116S最低;118S、B30S和117S柱头外露率都在60%以上。Y27S柱头活力保持时间最长,对照N5088S柱头活力下降最慢。参试不育系包颈率都较高,而闭颖率相对较低。     

水稻(Oryza sativa L.)温敏核不育系在有利于遗传型鉴别环境下的遗传改良

低不育起点温度(CSP)、高自繁育性和高的异交结实率对于水稻温敏核雄性不育系配制纯合的杂交种子和获得经济的自繁种子有重要意义。本研究分析了不同环境对这些性状选择效率的影响，结果表明，温敏核雄性不育系的雄性不育起点温度、自繁雄性可育性、柱头外露率和穗伸出率、生长势和适应性的选择效应受环境影响。在某种环境下遗传材料的这些性状过高的表达并没有导致高的区分度，因为在这种情况下性状在株间表现较整齐一致，温敏核雄性不育基因(tms)在高温下雄性不育性也表现相似的结果，因此认为有必要在适当有利于区分遗传型的环境下进行选择。在相对较低的温度条件下选择低的CSP和高的自繁雄性可育性有较高的选择效率；在较高的湿度条件下选择柱头外露较有效，而高的温度下选择穗的抽出率效率高．在相对低的土壤肥力环境下改良不育系的生长活力和适应性效率高。     

普通野生稻花器性状及异交结实性分析

以7个普通野生稻(Oryza rufipogon Griff.)和3个栽培稻(Oryza sativa L.)为材料,研究普通野生稻的花器性状和异交结实率及其相关性。结果表明,普通野生稻的花药长度和宽度、柱头长度和宽度及花粉量均比栽培稻大,但其花粉粒大小、花粉活力、花粉可育度和套袋自交结实率均比栽培稻小。相关分析结果表明,普通野生稻的花药长度与花药宽度、花粉量与花药宽度、柱头长度与柱头宽度、柱头宽度与花柱夹角分别呈显著正相关,花粉可育度与花粉活力呈极显著正相关;普通野生稻与栽培稻的异交结实率与其花器性状和套袋自交结实率之间无显著相关性。     

Identification of rape seed cultivars (Brassica napus) by starch gel electrophoresis of enzymes

Summary Isozyme patterns were used to characterize ten commercial rape seed (Brassica napus) cultivars. Extracts of cotyledons were made 4–7 days after germination and separated by electrophoresis on starch gels. A sample of more than 100 plants of each variety was analysed and stained for 4 polymorphic enzyme loci (Lap, Gpi, Acon, and Sdh). Therewith, it was possible to distinguish all ten rape varieties qualitatively by at least one typical enzyme pattern. Further, it could be demonstrated that all pairs of varieties showed clear qualitative differences in isozyme patterns, when only tow loci were screened (Acon, Sdh). Using ² test of homogeneity all pairs of varieties differ significantly in their frequencies of isozyme patterns for Acon and in all but one for Sdh.     

Floral display and breeding system of Jatropha curcas L.

Plant flowering and breeding characteristics are important for us to understand the reproduction of plant populations. In this paper, we studied the reproduction characteristics of Jatropha curcas in Yuanjiang County (23°36′N, 101°00′E), Yunnan Province. The plant produces flowers in dichasial inflorescences. Normally, the flowers are unisexual, and male and female flowers are produced in the same inflorescence. Only a few male flowers are produced in an inflorescence, and fruits are produced only through pollination between different flowers from the same or different plants. By the treatments of emasculation, bagging and artificial pollination in this experiment, there were few but same fruit set ratios when the inflorescences were emasculated, bagged, or bagged with net, except artificial pollination treatments, which showed that Jatropha curcas could produce fruit through apomixis but not wind pollination. When the inflorescences were unbagged, unemasculated and with free pollination treatments, or bagged, emascu- lated and with artificial cross-pollination treatments, or unbagged, emasculated and with free pollination treatments, there were many fruits produced. It showed that Jatropha curcas shows outcrossing, is self-compatible, and demanding for pollinators. Normally, the male flowers open first and a few flowers bloom in one day in a raceme. These flowers last a long time in bloom. However, a large number of female flowers open from the third to the fifth day, with some female flowers opening first in a few raceme. This shows a tendency to promote xenogamy and minimize geitonogamy.     

Innate factors causing differences in gene flow frequency from transgenic rice to different weedy rice biotypes

BACKGROUND: The compatibility and outcrossing rates between transgenic rice and weedy rice biotypes have been studied in some previous cases. However, few studies have addressed the reasons for these differences. The present study compared the compatibility and outcrossing rates between transgenic rice and selected weedy rice biotypes using manual and natural crossing experiments to elucidate the key innate factors causing the different outcrossing rates. RESULTS: Hybrid seed sets from manual crossing between transgenic rice and weedy rice varied from 31.8 to 82.7%, which correlated directly with genetic compatibility. Moreover, the significant differences in the quantity of germinated donor pollens and pollen tubes entering the weedy rice ovule directly contributed to the different seed sets. The natural outcrossing rates varied from 0 to 6.66‰. The duration of flowering overlap was the key factor influencing natural outcrossing. Plant and panicle height also affected outcrossing success. CONCLUSION: From this study, it is concluded that the likelihood of gene flow between transgenic rice and weedy rice biotypes is primarily determined by floral synchronisation and secondarily influenced by genetic compatibility and some morphological characteristics. Copyright © 2011 Society of Chemical Industry     

披碱草属植物的种间杂交和种质创新

披碱草属Elymus植物是小麦Triticum nestizum、大麦Hordeum vulgare的近缘属,同时蕴藏着丰富的优良基因,是改良小麦、大麦和黑麦Sacale cereale品种的优良基因资源。披碱草属植物也是草原和草甸的重要组成成分,具有极高的饲用价值和重要的水土保持功能,但国内在披碱草属植物资源和利用方面的研究与我国具有丰富的资源极不相称。现从国内外对披碱草属植物种间杂交利用方面进行论述,为充分开发利用我国丰富的披碱草属植物资源进行种质创新提供有价值的信息。     

五脉山黧豆开花动态及有性繁育系统的研究

观测了五脉山黧豆的开花动态,并用杂交指数(OCI)、花粉-胚珠比(P/O)方法测定了其有性繁育系统类型。结果表明,五脉山黧豆的花期持续45 d左右,盛花期为6月下旬左右。开花的日动态呈明显的双峰现象,2峰分别在8:00-11:00和14:00-15:00时出现。五脉山黧豆的杂交指数(OCI)=3,繁育系统为自交亲和,有时需要传粉者;花粉-胚珠比(P/O)=2 286.21,为兼性异交。得出其繁育类型为混交繁育系统,即自交和异交并存。五脉山黧豆的传粉系统不完善和虫害是结实率低的主要原因。     

水稻雄性不育系的胚囊育性及其对异交结实的影响

以3个光温敏核不育系W7415S、安农S、培矮64S和4个质核互作雄性不育系珍汕97A(夜公胞质)、珍汕97A(野败胞质)、华农A(夜公胞质)和华农A(野败胞质)为材料,通过观察各不育系成熟胚囊结构,并对异交结实率进行调查,以明确水稻雄性不育系异交结实率是否与胚囊育性有关.结果表明:不同水稻雄性不育系的胚囊育性与异交结...