栽培稻与普通野稻杂交杂种优势和农艺性状的遗传分析

按不完全双列杂交方式组配了12个栽培稻与普通野稻种间杂交组合,定量分析其杂种优势和利用加性-显性模型对11项农艺性状进行遗传分析.结果表明:12个栽野交组合的平均杂种优势为-0.608～3.031,穗数和籽粒长宽比表现强优势是其主要特征.栽野交的穗数、籽粒长宽比、结实率和抽穗期的优势显著高于籼粳交.各性状具有较高的广义遗传力(0.50～0.92);狭义遗传力为0.24～0.84,籽粒长宽比和抽穗期的狭义遗传力较高,其它性状中等偏低.各项农艺性状间具有显著或极显著水平的表型相关和遗传相关,可作为育种间接选择时的有效参考指标.

Breeding of New Japonica-indica Hybrid Rice Combination——Chunyou 618

[Objective] The aim was to select and breed Chunyou 618 which is a novel combination among japonica-indica hybrid rice subspecies. [Method] Chunyou 618 is a japonica-indica hybrid rice combination developed from Chunjiang 16A, a late japonica CMS line with dwarfness and early anthesis time, and C18, an indicaclinous wide compatibility restorer line. In addition, the concerning characters were researched. [Result] Chunyou 618, which is japonica inclining, proved high in pro- duction and in resistance to lodging with Cheng＇s index at 15. It is of moderate re- sistance against Xanthomonas oryzae and stripe virus disease, of moderate susceptibility on rice blast, and of susceptibility on Nilaparvata lugens. The indices of rice quality achieved departmental standard 4 and grade 4 of Cooking Rice Variety Quality, respectively. [Conclusion] Chunyou 618 enjoys strong heterosis, strong stem, good lodging resistance, large panicles, good cold tolerance, high yield and wide adaptability, which is suitable to be grown in Zhejiang Province as single cropping late rice.

Identification of the Parentage of Corn Variety Using SSR Markers

[Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primers, the artificial groups of two standard diad and two standard triad were respectively established as the verification materials. Genomic DNA of seedlings was extracted by using CTAB method. 137 pairs of SSR primers were selected for SSR amplification and product detection, which was used for the parentage identification of maize varieties. [ Result] Twenty pairs of corn primers with high polymorphism information content （ PIC value）, clearly amplified bands and good reproducibility were screened from 137 pairs of corn SSR primers tested. The identification results of using SSR molecular were consistent with the actual situation. [ Conclusion] It is feasible to identify the parentage of maize variety using SSR markers.

Interspecific Hybridization Between Crassostrea angulata and C. ariakensis

lnterspecific hybridization can generate heterosis, which is proven to be a useful tool in selective breeding programs for oyster culture. Crassostrea angulata and C. ariakensis are two important economic shellfish species in China. We conducted 2 × 2 reciprocal crosses to determine whether these two species can cross-fertilize and their hybrids can hatch, survive and perform hetero- sis. Fertilization was found symmetrical without delay. The rate of fertilization success of C. angulata ♀× C. ariakensis ♂ was lower than that of C. ariakensis ♀ x C. angulata ♂, and the success rate of both hybridizations was lower than that of two intraspecific crosses each. During the planktonic period, survival rate of the progeny was lower in the hybrid crosses than in the intraspecific crosses. On day 360, mean shell height of the progeny of C. angulata ♀ x C. angulata ♂ was highest, which was followed by that of C. angulata ♀ × C. ariakensis ♂, C. ariakensis ♀x C. ariakensis ♂ and C. ariakensis ♀× C. angulata ♂ in a descending order. Mor- phology of adults produced by the hybrid crosses was similar to that of C. angulata. Both hybrids underwent normal gonad devel- opment and produced mature gametes in the mating season. This study provided new insights into the quantitative traits in interspeci- fic crosses of Crassostrea species, thus being of guidance value for selective breeding of oyster.

Breeding of New Japonica-indica Hybrid Rice Combination Chunyou 59

Chunyou 59 is a japonica-indica hybrid rice combination developed from Chunjiang 16A(a late japonica CMS line with dwarfness and early anthesis time)and CH59(an indicaclinous wide compatibility restorer line).It has the characteristics of strong heterosis,strong stem,good lodging resistance,large panicles,good cold tolerance,high yield and wide adaptability.It was registered and released by Jiangxi Provincial Crop Variety Appraisal Committee in March 2009.The breeding procedure,characteristics,major techniques of cultivation and seed production of Chunyou 59 were introduced in the paper.

Heterotic patterns in rapeseed (Brassica napus L.) using exotic germplasm for Chinese semi-winter hybrid breeding

Chinese semi-winter rapeseed,genetically differing from winter and spring rapeseed,has been considered to possess strong potential as parent in winter and spring rapeseed hybrid breeding programs. However,no detailed researches have been documented whether winter and spring rapeseed lines have potential for Chinese semiwinter rapeseed hybrid breeding. The objectives of this study are to estimate the potential of winter and spring rapeseed for semi-winter rapeseed hybrid breeding,and to investigate the association of general combining ability(GCA) with adaptation of parental lines by combining with the data in our previous studies. Four winter and four spring male sterile lines were crossed with 14 Chinese semi-winter rapeseed lines to develop 112 hybrids,which were evaluated together with their parents for seed yield under three environments in China. The exotic parental lines were not adapted to local environment as demonstrated by late flowering,low seed weight and poor seed yield per se. However,the hybrids,especially derived from winter rapeseed exhibited strong heterosis for seed yield,indicating that winter rapeseed germplasm has a great potential for rapeseed hybrid breeding in China. Our data suggested a strong association of GCA with their adaptation ability of parental lines,since high to middle correlations were found for local parental lines and low correlations for exotic parental lines under spring,winter and semi-winter eco-growth environments. The hybrid breeding program using exotic germplasm in rapeseed was discussed.

Heterosis and combining ability:a diallel cross of three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino

We conducted a complete diallel cross among three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino to determine the heterosis and the combining ability of growth traits at the spat stage.The three populations were collected from Qingdao(Q) and Dalian(D) in China,and Miyagi(M) in Japan.We measured the shell length,shell width,and total weight.The magnitude of the general combining ability(GCA) variance was more pronounced than the specific combining ability(SCA) variance,which is evidenced by both the ratio of the genetic component in total variation and the GCA/SCA values.The component variances of GCA and SCA were significant for all three traits(P<0.05),indicating the importance of additive and non-additive genetic effects in determining the expression of these traits.The reciprocal maternal effects(RE) were also significant for these traits(P<0.05).Our results suggest that population D was the best general combiner in breeding programs to improve growth traits.The DM cross had the highest heterosis values for all three traits.

Estimate of Genetic Parameters of Grain Yield and Some Agronomic Traits in Durum Wheat Using Diallel Crosses

Five varieties of durum wheat were crossed in full diallel fashion through 2010/2011 growing season. The five parents and their 20 F1 progenies were grown in 2011/2012 at the farm of faculty of agricultural and forestry, Duhok university, Iraq, using randomize complete block design with three replications to estimate heterosis, heritability and some genetic parameters for yield and its components. The results showed highly significant difference among genotypes for all studied traits. The parent Um Raby-5 had a positive general combining ability effect for most traits including grain yield. The crosses （Kokorete71× LD - 357E）, （Crezo × Um Rahy-5）, （Cimeto×Um Raby-5）, （Cimeto×crezo） and （Cimeto × Kokorete 71） exhibited significant desirable specific combining ability effect for most traits. The dominance was greater than additive almost traits. Heritability inbroad sense was high but heritability in narrow sense was low. The expected genetic advance as percent of traits mean was low for all traits. Most crosses showed significant positive heterosis for most traits and two crosses, （Crezo Cimeto） and （Cimeto Urn Raby-5） had the highest positive heterosis for the most studied traits including grain yield.

A Study on Combining Ability and Heritability of Agronomic Trait of Indica Hybrid Rice

In present study, under North Carolina design Ⅱ, 5 sterile lines and 2 restorer lines were analyzed by crossing test so as to study the combining ability, habitability and correlation of each major agronomic characters. The results showed that plant height, panicle length, filled grains per plant, grains per plant, 1 000-grain weight, yield per day, yield per plant by parent gene additive effect, seed set of parent gene additive and the additive effect work together, additive effect played a relatively important role, effective tillers per plant by additive genes of the parents and the additive effect had more consistent effects on offspring traits. General combining ability effect analysis showed that the better parents were P1A and R102. The special combining ability of plant height and panicle length in hybrid rice combination was mainly correlated with the general combining ability of restorer line, whereas not with the general combining ability of parent. For the other 7 traits, if the general combining ability of both parents was higher, the special combining ability of hybrid F1 combinations was also higher. The best combination of special combining ability of 9 traits in hybrid rice was P2 A/R102, followed by P1 A/R102.

Grey correlational and SSR analyses of cotton hybrids

Ten upland cotton strains exhibiting 3 fiber quality traits and 8 yield traits, were grown for two years in an investigation of the correlation between grey relational analysis （GRA） and genetic identity in heterosis of cot- ton hybrid. The aim was to establish the optimal approach for heterosis prediction and parent selection. Plant traits data were collected and analyzed for GRA. In addition, 72 simple sequence repeat （SSR） markers were examined and 148 polymorphisms were detected. Correlation analysis of GRA, genetic identity, Ft fiber quality and yield heterosis was conducted. Significant differences were observed between the two analytic methods, whereas compa- rable predictions were given for yield heterosis. GRA for yield exhibited slightly higher correlation than genetic identity analysis, with a correlation coefficient of 0.49. GRA and genetic analysis exhibited overlapping yet dis- tinct advantages in heterosis prediction. Therefore, these analytical methods should be integrated to achieve the op- timal heterosis prediction and parent selection.

Studies on Heteroses of Pei'ai 64S/Javanica Rice

Agronomic traits and heteroses of javanica varieties and the indica/javanica hybrids in Changsha are reported. Javanica rice exhibits long panicles, big grains, less panicles per plant, a long growth duration and high plant height in Changsha. The hybrid of Pei'ai 64S/javanica possesses positive heterobeltiosis in culm height, panicle length, panicles per plant, spikelets per panicle, grains per panicle, yield per plant, theoretic yield per hectare and actual yield per hectare; performs negative heterobeltiosis in days to flower, seed setting rate and 1000-grain weight. There are significant linear regression relations between culm height of the hybrid and panicle length of its male parent, panicle length of the hybrid and that of its male parent, spikelets per panicle of the hybrid and spikelets per panicle and panicle length of its male parent, grains per panicle of the hybrid and spikelets per panicle of its male parent, 1000-grain weight of the hybrid and spikelets per panicle of its male parent, respectively. In general, significant differences at 1% level are seen in most traits except grains per panicle and theoretic yield per hectare between the indica/javanica hybrid and Pei'ai 64S/Teqin (CK). Compared with the check, the indica/javanica hybrids have positive Standard heterosis in culm height, panicle length, spikelets per panicle, grains per panicle and 1000-grain weight but negative standard heterosis in days to flower, panicles per plant, seed setting rate, theoretic yield per hectare and actual yield per hectare. For the individuals, 11.1% hybrids possess > 40% standard heterosis in theoretic yield per hectare, 3.7% possess >40% standard heterosis in actual yield per hectare. The javanica restorer line 770 derives from a single cross of Pei'ai 64S/Moroberekan B-51-4-9-2. The hybrid 43S/770 possesses an elite plant type and strong heterosis.