Abstract:Seven hundred rice landraces which were distributed in six geographic groups in China were analysed using nine isozyme loci. The results showed that the genetic diversity of rice was the most in Yunnan, secondly in the Huaihe River. We suggested that there are three centers of genetic diversity for Chinese cultivated rice, i.e. Yunan, the upper reaches of the Huaihe River-the middle and lower reaches of the Yangtze River and South China. The center of origin of Chinese cultivated rice is probably in the middle reaches of the the Yangtze River-the upper reaches of the Huaihe River. Combining with the data of archaeology and other former results, we propose that Yunnan is not the center of origin of Chinese cultivated rice but probably is the secondary center which was strongly influenced by the center of origin of South Asia cultivated rice.

Abstract:The genetic diversity of 18 soybean cultivars in Fujian were analyzed by RAPD markers. Among 91 RAPD bands obtained from 12 primers, 65 bands were polymorphic which occupied 71.43% of the whole amplified bands. Cluster analysis showed that the tested materials could be divided into three groups at the level of D 0.62, the vegetable soybean materials, the cross-breeding and local varieties and the varieties with semiwild kindred relationship. It also exhibited their relationship related with the geographic origin.

Abstract:Genetic diversity of 45 Chinese Sea Island Cottons and 8 foreign Sea Island Cottons were studied based on SSR (Simple Sequence Repeats ) markers.Twenty-four SSR primers were selected from 256 primers to evaluate the genetic diversity of 53 Gossypium barbadense L. germplasms. Totally 106 alleles were observed among which, 97 (91.5%) were polymorphic. The number of DNA bands per primer ranged from 2 to 8 and with the average of 4.4. The average polymorphism information (PIC) was 0.688,with the range from 0.245 to 0.848. Cluster analysis by the unweighted pair group method of arithmetic means (UPGMA) showed that 53 varieties were clustered into 2 main groups based on Jaccard similarity from the SSRs and Euclid distance from 17 agronomic traits data. Classification of all genotypes gave similar results with their line sources. Genetic relationships and the genetic similarity obtained from the analysis is used for the evaluation of varieties and genetic diversity.

Abstract:Twenty inbreds were classified by RAPD markers(random amplified polymorphic DNA procedures). The materials included six main inbreds (Dan 340, Zi 330, 7922, Su37, 449 and Huangzaosi), which represented six main heterotic groups(Luda Red Cob, Lancaster, Reid, Suwan, Mobai and Sipingtou)of maize backbone inbred lines in karst high elevation mountainous area in China. Total 136 DNA polymorphic bands were produced from 21 primers which were screened out from 90 random primers, and an average proportion of polymorphic loci was 86.3%. Cluster analysis by unweighted pair group method of arithmetic means(UPGMA)suggested that 20 inbreds could be divided into 5 groups with genetic distance from 0.632.

Abstract:The genetic diversity and genetic relationships among 60 accessions of barley, including 33 Chinese landraces, 19 wild relatives from Tibet and 8 cultivars from other countries, were evaluated by RAPD markers. Totally 119 bands were detected with 32 primers, with the average of 3.72. Eighty-seven polymorphic bands were detected, representing of 73.11% of polymorphic bands (PPB) and 0.434 of mean polymorphism information content (PIC), respectively. The average number of alleles (Ne) was 2.304. One to eight polymorphic bands were generated by each primer. Among 60 barley accessions, the RAPD-based genetic similarity (RAMP-GS) ranged from 0.757 to 0.981, with the mean of 0.871. The mean GS of 19 wild barley accessions, 33 Chinese and 8 foreign cultivars were 0.892,0.879 and 0.882, respectively. UPGMA cluster analysis showed that these accessions could be divided into five groups and the genetic diversity based on RAPD markers was correlated with their geographical distribution.

Abstract:A Specially-long pod variant line was selected from resynthesized B. napus lines derived from an distant crossing between a landrace of B. campestris L. , collected in eastern Tibet, and a vegetable cabbage, B. oleracea vat. alboglabra Bailey from Yunnan in China. The average length of pods at the middle of main racemes was about 20cm, with a body length of 16- 18cm and a beak length of about 3cm. The longest pod from this variant line reached 31.5cm, with a body length of 26. lcm and a beak length of 5.4cm. This is a line with specially long pods rarely seen in Brassica species. The average pod length of the variant line was about 3 times that of the common B. napus. It has been genetically stable and is named Chuannong Techangjiao. The breeding process and the main characteristics of the specially-long pod variant were reported and the breeding and research values were briefly analyzed in the paper.

Abstract:Twenty-four SSR loci which were distributed evenly among the genome of cultivated rice were selected to assess the genetic diversity of 343 Oryza rufipogon individuals from 12 populations along the Haojiang River, Wuxuan County, Guangxi Zhuang Autonomous Region in China. The results indicated that: (i) Abundant genetic diversity existed: among 206 detected alleles, the percentage of polymorphic loci (p) ranged from 79% to 100% with the mean of 92.36%; the number of alleles per locus (Al) ranged from 3 to 19 with the average of 8.7083; the number of effective alleles (Ae) ranged from 1.2300 to 11.4195 with the mean of 3.7117; the Shannon's information index (I) ranged from 0.5540 to 1.1138 with the overall of 1.3692. (ii) High genetic differentiation among populations and gene flow were detected (Gst=0.2659; Nm=0.6901), suggesting that 26.59% genetic variation existed between the populations. (iii) Many rare alleles were detected. In 206 alleles, 65 were existed only in one or two populations, 12 of which existed only in population B. (iv) The results of cluster analysis and principle coordinates analysis (PCO) showed that population A and B from the downstream were close; population C from the middle was unique and became a cluster singly; the population D, E, and G from the middle were close; the population H and I from the middle and K, L from the upstream were close. It could be suggested that the populations from the middle and downstream of the Haojiang River, especially population B, D and H should be given priority to be conserved in-situ.

Abstract:Fokienia hodginsii flowers twice a year: one is spring flowering from April to May and the cone is ripe in October of the same year, while the seed has not viability; the other is autumn flowering that from September to October, and the cone is riping in October of next year, while the seed has viability. Biological and phenological characters of flower and cone are closely linked to geography and climate factors including place, altitude, temperature of natural distribution area and so on. Autumn flowering, fruit, maturity and seed falling were in mountainous areas earlier than in lower mountainous areas, and much earlier than in hilly areas, and in high altitude areas earlier than in low altitude areas. Phenology of flower and cone is the same among different provenances in same area and altitude. There were not obvious differences in the characters of cone and seed, one cone weight, thousand-seed weight and germination percentage. Phenology of flower and cone is different among different provenances in different areas altitude; there are obvious differences in the cone diameter, cone height, seed number, thousand-seed weight and germination percentage.

Abstract:Field experiments of four locations were conducted in 1999 and 2004 in Zhangye city of the Western Yellow River Corridor of Gansu province. Experimental maize varieties 608, Jiudan 3 and Zhongdan 2 belongs to different maturation groups. The elevations of four experimental locations is 1506.5,1706.5,2000.0 and 2231.5 m respectively. The results indicated that maturation was delayed gradually with the rise of elevation under same sowing condition. There was a significantly positive correlation between elevation and days of sowing to maturation for the maize varieties. Growth stage delayed 5 - 6 d with elevations raising per 100 m. The positive correlation had been shown between the elevation and days of sowing to elongation. There was a negative correlation between the elevation and plant height of maize varieties.

Abstract:The genetic diversity of 59 maize inbred lines and one teosinte accession was analyzed by using ISSR markers. With 21 ISSR primers, totally 475 alleles were detected among which 469 were polymorphic, and the average number of alleles for one primer was 22.6. Polymorphic information content (PIC) ranged from 0.84 to 0.94. The similarity coefficient of 60 accessions ranged from 0.23 to 0.48. Cluster analysis based on ISSR data showed that the accessions could be categorized into two groups and further 9 sub-groups,to some extent in accordance with the pedigrees of the entries and with some exceptions. Therefore, the present study indicated that ISSR marker was not the best marker system for assessment of genetic diversity although it might reveal genetic relationships among accessions. It was suggested that ISSR be used for assessment of genetic diversity in under-researched or neglected crops.

Abstract:Vitamin E is essential to human being and animal. Primary evaluation of 20 sunflower (Helianthus annuus L.) seeds was carried out with the characters of vitamin E content, oil content, hull content and 100-seed weight. The results showed that vitamin E content of oil sunflower was significantly higher than that of confectionary sunflower. Vitamin E was correlated with oil content positively at 0.01 levels. Oil content and hull content affected 100-seed weight with a significant negative correlation at 0.05 and 0.01 levels, respectively. Three valuable germplasm were selected for sunflower breeding to improve vitamin E content.

Abstract:Phytophthora root rot caused by Phytophthora sojae is a destructive disease for soybeans throughout the soybean production regions of world. Utilization of resistant varieties is the most economical and environmentally safe method for controlling the disease. The study screened for resistance of wild soybeans to Phytophthora root rot and investigated their geographical distribution. Four hundred and twelve wild soybean accessions were identified for their reaction to P. sojae strain USAR1 with virulence 1a, 1d,2,3b,5,7 using an agar pluginoculation in seedling. 13.4 % accessions were resistant and 15.3 % accessions were intermediate response. The results indicated that the distribution of Phytophthora resistant wild soybeans was extensive in China, in which it was the most abundant in Anhui province.

Abstract:Responses of permeability in six wheat varieties to Fusarium graminearum crude toxin were studied under different stress time and different toxin concentration. The results showed that root cell membranes were all susceptible in 72 hours' toxin stress. Relative electric conductivity increased with the increasing of toxin concentration and the elongation of toxin stress time. Resistant varieties had stronger resistance to toxin stress than susceptible varieties and increment of relative electric conductivity were lowest. The increment of membrane permeability was all highest after 72 hours' stress and showed significant difference. Then the increment of membrane permeability of resistant varieties decreased.

Abstract:Identification of resistance of Brassica campestris L. ssp. chinensis germplasm resources to Plutella xylostella was conducted by artificial inoculation in the greenhouse. The result showed that pest index ranged between 18.10- 100.00 accessions resistance were significantly different and classified into six, corresponding HR, R,MR,MS, S, HS. Among them, six accessions behaved highly resistant and eleven resistant to Plutella xylostella. The result also indicated that the resistance of materials to Plutella xylostella was significantly related to crinkle of leaf surface. Smooth leaf surface accessions was most potential for selecting resistant materials.

Abstract:为了进一步利用东方小麦(Triticum turanicum Jakubz.)遗传资源,对来自埃塞俄比亚、伊拉克、伊朗、阿塞拜疆、阿富汗、摩洛哥等国家共87份东方小麦醇溶蛋白位点的遗传多样性进行了分析.结果发现,供试材料存在丰富的遗传变异,87份材料共产生72种谱带类型,分离出33条带纹,每份材料可电泳11～22条带,平均16条;在α、β、γ和ω四个区均差异较大,分别有16、11、20和20种谱带变异类型.聚类分析发现,醇溶蛋白揭示的材料间遗传多样性与其地理来源有一定关系.

Abstract:Using high yield cultivated soybean as recurrent parents, we made the backcrosses with intermediate materials which were derived from the cross combinations between wild and cultivated soybeans. Three new elite germplasms were developed, with protein contents above 45%, and the total of protein and oil contents above 63%. Longpin8802-1, one of the three elite germplasms, is resistant to phytothora rot and frogeye leaf spot, and its protein content, oil content and total of both protein and oil content are 45.64 %, 18.42 % and 64.06%, respectively. Longpin01-757 is resistant to frogeye leaf spot, and its protein content, oil contents and total of both protein and oil contents are 45.99%, 19.40% and 65.39%, respectively. Longpin9501 has the medium resistance to frogeye leaf spot , and its protein content, oil content and total of both protein and oil content are 45.11%, 18.32 % and 63.43 %, respectively. The data suggest that it is very effective way to broaden soybean genetic basis and develop the new soybean germplasms with high quality and resistance to diseases and good agronomic characters, using high yield cultivated soybeans as recurrent parents to make the backcrosses with interspecific enhancement.

Abstract:利用农艺性状优良、优质的红粒小麦品种绵阳11以及2个白粒、极易穗发芽(常年穗发芽在50%以上)的小麦品系YY2和88-1643与穗发芽抗性来源于长休眠节节麦的人工合成小麦RSP杂交,对3个组合的F2单株和F3株系的穗发芽测试,从RSP×绵阳11中筛选出15个与RSP相当的纯合抗性株系和27份穗发芽接近0的F3单株;从RSP×YY2和RSP×88-1643组合中共筛选出5份穗发芽在7%以下的白粒株系.这些株系或单株相对于RSP的高秆、晚熟等不利性状已有较大改良,为节节麦抗穗发芽基因向优质或白粒小麦转移研制出了更容易利用的中间材料.

Abstract:本研究以国内育成和国外引进的52份转基因抗虫棉品种(系)为材料,在河北农业大学棉花育种圃种植,调查农艺性状、测定纤维品质,基于农艺性状和纤维品质分析供试品种(系)的遗传多样性.结果表明:在9个农艺性状中,烂铃数的变异系数最大,其次为产量、有效铃数和第一果枝节位高度,变异系数最小的是衣分和果枝数.转基因抗虫棉品种纤维长度基本能够满足纺织工业需求,2.5%跨长主要集中在28～30mm;纤维比强度平均值为27.1cN/tex,变幅为23.0～31.6cN/tex;马克隆值的平均值为4.8,变幅为4.0～5.6.成对品种的欧氏距离变化在1.53～13.31之间,平均值为4.79,单一品种欧氏距离的平均值分布在3.62～10.51之间,表明不同品种之间具有一定的差异.采用离差平方和法对欧氏距离进行聚类,可以将供试品种明显地划分为2类,一类为中熟品种,另一类为早熟品种.

Abstract:Grain qualities between the compact panicle type Japonica rice (CPJR) and the loose panicle type Japonica rice (LPJR) were compared. The results showed that obvious differences of chalkiness among varieties in the two panicle types of rice. The average chalkiness of the two CPJR varieties (lines) was worse than the two LPJR varieties. The chalky grain rate of EA6 with CPJR was about 1/2 that of Xiushui 63 (same CPJR as EA6), similar to Xiushui 11 with LPJR, and about one time higher than Koshihikari (a Japanese variety with LPJR and excellent grain qualities). The chalkiness degree of EA6 was about 1/2 that of Xiushui 63 and Xiushui 11, respectively, and above one time higher than Koshihikari. The chalkiness traits of grains situated different part of panicle showed that actions of the chalkiness were more significant on the total chalkiness of varieties (lines) in the bottom grain than the top and the middle ones within panicle, and that the actions were stronger on CPJR than LPJR. In addition, EA6 also showed significantly or much significantly better all the testing characters except scent than Xiushui 11, and approximate majority testing characters compared with Koshihikari. However, Xiushui 63 with CPJR showed almost similar in all the testing characters to Xiushui 11, and significantly worse ones except scent than Koshihikari. The above results implicated that it was possible for CPJR to reach, even exceed LPJR in grain qualities.

Abstract:Retrotransposons are mobile genetic elements that make up a large fraction of most eukaryotic genomes. They are particularly abundant in plants, as a principal component of nuclear DNA. Retrotransposons can be divided into two main categories, those with long terminal repeats (LTRs), such as retroviruses and LTR retrotransposons (Ty1-copia type and Ty3-gypsy type), and those lacking such repeats, as long interspersed nuclear elements (LINE type) and short interspersed nuclear elements (SINE type). Most retrotransposons sequences normally show inactive, but some could express under biotic and abiotic stress. Differences observed in plant genomes can be attributed to retroelement amplification leading to genome expansion. So retrotransposons contribute greatly to the genetic diversity and genome size variability of plants. Up to date, active retrotransposons have been introduced into a few plant species. These elements have been used as a powerful tool for studying plant gene functions and expression. In this paper, the progress of plant retrotransposons for recent years is systematically reviewed from the following aspects: structure, charateristics, activation, effection of plant genome and application of fuctional genomics.

Abstract:Salt or alkaline soil is the main restricting factor of steady steady development in rice production. In order to improve salt or alkaline tolerance in rice, expand plant area and reduce low product caused by salt or alkaline stress, a lot of researches have conducted studies on genotype diversity, physiology and biochemistry, genetics and gene mapping of salt or alkaline tolerance in rice. But there is not a standard method for characterization and evaluation on salt or alkaline tolerance in china, which affects further development salt or alkaline tolerance of rice. This paper describes the methods of characterization and evaluation index and grading standard of salt or alkaline tolerance of rice in the world, providing the basis for standard methods of characterization and evaluation of salt or alkaline tolerance in rice, characterization of rice germplasm, physiologic biochemistry analysis and genetic breeding.

Abstract:唐古特白刺(Nitraria tangutorum Bobr.)是白刺属中较进化的植物种,众多克隆株系形成"白刺包",具有重要的生态防护价值,其浆果状核果也具有较高的经济利用价值.由于种内异交和种间杂交,唐古特白刺种内变异十分丰富,其中表现最为明显的是果实性状变异.而果色、果味、果序重等性状差异,对于生产成本、加工工艺以及产品质量等都有较大影响,从而限制了白刺果的产业化开发.开展种质资源、优树选择、杂交和倍性育种等方面的研究,对唐古特白刺进行遗传改良,选育高产、味佳、核小、色泽美观且生态价值高的果用与生态兼用型白刺品种,并进一步使其无性系化、种植园化,则是推动沙区白刺资源开发、利用以及当地生态与经济发展的关键.

Abstract:回顾了对作物种质资源价值的认识过程,对作物种质资源价值评估的理论和方法进行了论述,指出了作物种质资源价值评估及其产权保护的必要性,对作物种质资源价值评估一些问题和难点进行了探讨,并对今后研究提出了建议.

Abstract:The stripe rust-resistant wheat variety 9365 was developed by the Wheat Research Center of Shaanxi Province. It has the characteristics of high resistance to stripe rust, large ear, more tillers, high yield and excellent comprehensive agronomic traits. 9365 is a new excellent source of resistance to stripe rust for wheat breeding in Shaanxi Province. The shortcoming of 9365 is the high plant,late maturation and the resistance to stripe rust controlled by recessive genes.

Abstract:本项研究重点是要探讨通过油菜与蔊菜远缘杂交,将蔊菜的某些优良性状转移到栽培油菜中的可行性.结果表明甘蓝型油菜与蔊菜进行远缘杂交有较好的亲和性.而且其杂交后代变异明显,出现了许多碎叶型植株和一些类似白菜型的植株,杂交后代对菌核病有较强的抗性,有许多具有优势的单株.油菜与蔊菜进行远缘杂交对于创新油菜种质资源,培育高产、高抗油菜新品种具有重要意义.