Cryopreservation of immature embryos of Theobroma cacao

Immature, white zygotic embryos of Theobroma cacao L. (cacao) retained the ability to produce callus and to undergo somatic embryogenesis after slow hydrated freezing and desiccated fast freezing in liquid nitrogen. The highest rate of somatic embryogenesis occurred in embryos which were precultured on a medium containing 3% sucrose, frozen slowly with cryoprotectants before exposure to liquid nitrogen, and recovered on a medium containing 3 mg/liter NAA. Embryos precultured on media containing sucrose increasing to 21% had a higher rate of survival but were less embryogenic after freezing. These results suggest that immature embryos might be used for long-term germplasm storage of T. cacao germplasm.     

Cryopreservation of sugarbeet germplasm

Meristems aseptically isolated from shoots developed on sugarbeet (Beta vulgaris L.) inflorescences were precultured on modified MS agar medium containing 19.4 M 6-benzylaminopurine, 6 M triiodobenzoic acid, and supplemented with 5% DMSO. After two days the meristems were transferred to liquid modified MS medium and the cryoprotectants sorbitol and DMSO added in varying concentrations. The meristems were frozen to –40°C and stored in liquid nitrogen. Growth resumed when the meristems were quick-thawed at 39°C.     

充分利用福建滨海沙滩植被资源发展种植业

福建滨海沙滩位于北纬23°37′—27°10′范围,面积约5.33×10~4ha,已植防护林近2.0×10~4ha,尚约有3.34×10~4ha 未开发利用,其中分布于闽江口以南岸段和岛屿约2.86×10~4ha,     

台湾早熟蜜桃优良芽变新种质'五月红'的鉴定

桃是我国重要的果树种类,分布十分广泛,在水果生产中排第四位,但适合南方栽培的品种却稀少。该研究通过资源调查在广西大学标本园内的一棵台湾早熟蜜桃大枝上发现一个芽变新种质,命名为‘五月红'',并进一步对其主要生物学特性、植物学性状以及果实经济性状等进行观测分析,同时还通过SRAP分子标记检测与母株台湾早熟蜜桃的差异性。结果表明:‘五月红''芽变新种质成熟期比台湾早熟蜜桃提前20 d左右,5月上中旬成熟,果变大,核变小,可食率提高,且颜色均匀,可溶性固形物含量显著提高,保持了台湾早熟蜜桃需冷量低、品质优良和风味极佳的优点,属于特早熟优质种质资源; 通过琼脂糖电泳检测SRAP扩增组合引物me9/em5在‘五月红''DNA样品中能够扩增到1 200 bp大小的特异性条带,表明‘五月红''在DNA遗传水平上与母株台湾早熟蜜桃发生了变异,属于新的特早熟种质资源。‘五月红''芽变新种质的发现将为选育适合南方栽培的特早熟桃品种提供重要材料,有助于优化不同熟期品种的栽培结构,进而促进南方桃种植产业经济效益的提高。     

213份苎麻种质资源农艺性状及品质性状鉴定评价

对213份苎麻种质的农艺性状和品质性状进行了分析和评价。结果表明,农艺性状和产量以及纤维品质存在丰富的变异;8个性状间存在着不同的相关性;筛选出高产种质(单蔸产量≥110g)56份,优质种质(纤维细度≥2200m/g)38份,高产(单蔸产量≥110g)优质(纤维细度≥2200 m/g)的种质5份。     

Recent Progress on Rice Genetics in China

Through thousands of years of evolution and cultivation, tremendously rich genetic diversity has been accumulated in rice （Oryza sativa L.）, developing a large germplasm pool from which people can select varieties with morphologies of Interest and other important agronomic traits. With the development of modern genetics, scientists have paid more attention to the genetic value of these elite varieties and germplasms, and such rich rice resources provide a good foundation for genetic research in China. Approximately 100 000 accessions of radiation-, chemical- or insertion-induced mutagenesis have been generated since the 1980s, and great progress has been made on rice molecular genetics. So far at least 16 variant/mutant genes Including MOC1, BC1, SKC1, and Rfgenes have been isolated and characterized in China. These achievements greatly promote the research on functional genomics, understanding the mechanism of plant development and molecular design breeding of rice in China. Here we review the progress of three aspects of rice genetics in China： moving forward at the molecular level, genetic research on elite varieties and germplasms, and new gene screening and genetic analysis using mutants. The prospects of rice genetics are also discussed.     

Inheritance and Expression of Copies of Transgenes 1Dx5 and 1Ax1 in Elite Wheat （Triticum aestivum L.） Varieties Transferred from Transgenic Wheat through Conventional Crossing

To study the inheritance and expression of multiple copies of transgenes from transgenic wheat lines, three crosses between transgenic wheat lines B72-8-11b and B102-1-2 and Chinese elite wheat varieties Chuan89-107 and Email 8 were carried out. Chuan89-107×B72-8-11b, Chuan89-107×B102-1-2 and Email 8×B72-8-11b, and F_1 plants were selfed or backcrossed to obtain different generation populations. Protein analysis in grains of F_1 and F_2 and backcross progenies of BC_1F_1, BC_1F_2, BC_1F_3, BC_2F_1, BC_2F_2 and BC_2F_3 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the transgenes lDx5 and lAx1 were expressed and segregated in the target wheat according to Mendelian laws. A range of lDx5 expression levels were observed in the progenies of Chuan89-107×B72-8-11b and Emai 18×B72-8-11b, but the expression levels of lAx1 in progenies of Chuan89-107×B102-1-2 rarely changed. It suggested that the two foreign genes had different mechanisms of expression in the cross progeny, even though they were produced in the same way and the foreign lDx5 gene of 5-10 copies had the more complicated expression mechanism than the lAx1 gene of 4-5 copies.     

基于本体的农作物种质资源平台用户模型研究

针对国家农作物种质资源平台的特点,提出了基于本体的分组分层动态用户模型构建方法。首先建立用户结点,由用户注册信息结合领域本体构建初步的分组用户模型;然后挖掘用户日志扩展、定期更新用户模型;最后利用通用本体WordNet进行同义词、不同语种的语义扩展,进一步优化用户模型。利用开源软件protégé构建了农作物种质资源核心本体,添加个人信息映射构成用户模型,计算用户对资源的兴趣度,并增加了时间因素来表明用户的兴趣随时间发生变化的情况,便于用户模型的动态更新。基于本体的分组分层动态用户模型可以给不同用户提供个性化服务,有利于提高平台的服务质量。