斑节对虾双季养成期间虾池水质和底泥细菌含量的变化

本文报导了斑节对虾双季人工淡化养殖,虾池水与底泥异养菌和弧菌的数量变化及其与主要理化环境因子的关系。表明上半年的第一茬养殖虾池无论是水或底泥的异养菌数和弧菌总数均容易调控在低数量水平,第二茬养殖由于高水温持续整个养殖周期,诸多环境因子波动较大,在人工管理调节下,虾池主要环境因子(细菌数、化学耗氧量、氨氮、溶解氧、pH值)仍处在正常的范围内,但是却显示不出它们之间的相关性,在两茬的养殖中底泥异养菌数和弧菌数都分别比水中高两个数量级和一个数量级。     

Relationship between anther culture response and aluminium tolerance in wheat (Triticum aestivum L.)

A combination of in vivo and in vitro selection methods were used to increase aluminium tolerance in wheat using wheat x triticale crosses. Both in vivo and in vitro aluminium treatments significantly influenced the anther culture response. In vivo selection at the seedling stage resulted in significantly higher embryo induction. On induction media containing aluminium, the embryoid induction frequency dropped significantly, but there was an increase in the green plant regeneration frequency. In spite of this effect, all doubled haploid (DH) lines were more tolerant to aluminium in seedling tests than the winter wheat parent. The application of in vivo aluminium selection, before the start of anther culture, increased the probability of obtaining DH lines with significantly higher tolerance, compared to the original population. After three selection cycles of the original populations, there was a significant difference in the root regrowth rate of tolerant and sensitive plants. Both sensitive and tolerant plants showed a decrease due to the presence of aluminium in the induction media, with a greater decrease occurring in sensitive plants. Correlation between the rate of root regrowth in the seedling test and the change in embryo induction was positive, but moderate, emphasising the fact that plants with higher root regrowth tended to be more tolerant of the presence of aluminium in the induction medium. This revised version was published online in August 2006 with corrections to the Cover Date.     

新疆罗布麻属和白麻属植物的染色体数目

本文报道了罗布麻属(Apocynum Linn.)1种和白麻属(Poacynum Baill.)2种的染色体数目,其体细胞染色体数均为2n=20,其中白麻和大叶白麻为首次报道。     

1类最大度为6的平面图的全着色

证明了:如果图G是不含3-面上有5-顶点和(4,6,6)-面的最大度为6的平面图,则它满足全着色猜想,即对图G有Δ(G)+1≤χT(G)≤Δ(G)+2.     

胶园单位面积有效割株变化及其原因分析

搜集了近年来我国植胶生产上的相关资料,在此基础上,初步分析了橡胶树种植密度、单位面积定植株数、有效割株数、有效存株率和存株类型的变化情况,以及胶园单位面积有效割株对胶园土地产出能力的影响及其原因,提出了提高我国胶园有效存株的建议。     

Heterosis Study on Developmental Behavior of Flowering and Boll Setting in Upland Cotton

The developmental behavior was examined for flowering and boll setting in upland cotton （Gossypium hirsutum L.） at different boll-setting sites and blooming periods. Conventional and conditional methods were applied to analyze heterosis by an additive-dominance model with genotype by environment （GE） interaction effects. Positive general heterosis was significantly detected on middle-lower nodes at positions 1 and 2 for a number of flowers and bolls per plant. Deviation between HPBE1 and HPBE2 was relatively large for a number of flowers per plant at positions 3, 4, and 5, but much smaller for number of bolls per plant. There was increase of heterosis before the end of July, and the highest heterosis was observed at 22 DAF （22 days after flowering） for flowers and at 16 DAF for bolls, and then declined. There existed significant diversity of interaction heterosis for flowers as well as for bolls during blooming stages, but deviation between HPBE1 and HPBE2 was smaller for number of bolls per plant than that of flowers per plant. The cross of DP-15 （late-season variety）＇ HG-H-12 had positive general heterosis since 19 DAF, and negative HPB was observed for the cross of GL-5 （early-season variety）＇ HG-H-12 after 37 DAF. Interaction heterosis was mostly not significant for cross DP-15＇ HG-H-12, but the reverse was true for cross GL-5＇ HG-H-12. Positive conditional HPB was detected since 16 DAF until 43 DAF for cross DP-15＇ HG- H-12, and before 13 DAF for cross GL-5＇ HG-H-12.     

姜科植物染色体制片方法的优化

以白姜花根尖为材料,通过预处理、固定、解离和染色等步骤,对染色体制片技术进行改良,得到了一种简单高效的可用于植物染色体数目分析的制片技术,主要步骤包括取材-酸解离-低渗-染色-压片。采用改良技术得到的制片细胞膨大、染色体分散、形态清晰、分色良好。用该方法对白姜花、金姜花、所罗门姜黄和红艳郁金等的体细胞染色体数目进行检测,结果分别如下:白姜花2n=34,金姜花2n=34,所罗门姜黄2n=63,红艳郁金2n=49。     

四种豆科牧草花药及组织培养研究的总结

利用生物技术方法,对红豆草、苜蓿、百脉根和鹰嘴紫云英进行花药培养及茎尖、茎段的组织培养,诱导愈伤组织、分化成苗且移栽成功。同时对无根苗直接移栽土壤中刺激生根,得到了满意的结果。通过多个品种和30多种培养基的试验,筛选出最适的各类培养基。为利用生物技术进行牧草育种和快速繁殖提供了科学依据。     

Detection and analysis of genome-wide copy number variation in the pig genome using an 80 K SNP Beadchip

Copy number variation (CNV) is an important source of genetic variability in human or animal genomes and play key roles in phenotypic diversity and disease susceptibility. In the present study, we performed a genome-wide analysis for CNV detection using SNP genotyping data of 857 Large White pigs. A total of 312 CNV regions (CNVRs) were detected with the PennCNV algorithm, which covered 57.76 Mb of the pig genome and correspond to 2.36% of the genome sequence. The length of the CNVRs on autosomes ranged from 1.77 Kb to 1.76 Mb with an average of 185.11 Kb. Of these, 220 completely or partially overlapped with 1,092 annotated genes, which enriched a wide variety of biological processes. Comparisons with previously reported pig CNVR revealed 92 (29.49%) novel CNVRs. Experimentally, 80% of CNVRs selected randomly were validated by quantitative PCR (qPCR). We also performed an association analysis between some of the CNVRs and reproductive traits, with results demonstrating the potential importance of CNVR61 and CNVR283 associated with litter sizes. Notably, the GPER1 gene located in CNVR61 plays a key role in reproduction. Our study is an important complement to the CNV map in the pig genome and provides valuable information for investigating the association between genomic variation and economic traits.