To improve agronomic traits of partial waxy wheat, crossing between Chinese Baihuomai and wheat cultivars PH85-16, Jinan 17, and Yannong 15 was performed. The progeny plants were further backcrossed to these cultivars...To improve agronomic traits of partial waxy wheat, crossing between Chinese Baihuomai and wheat cultivars PH85-16, Jinan 17, and Yannong 15 was performed. The progeny plants were further backcrossed to these cultivars as recurrent parents for five generations. To get homozygous plants with the null allele at the Wx-D1 locus, self-pollination was carried out in the BC5F1 generation. Through another three generations, 6 partial waxy wheat lines were obtained, which had similar agronomic performance as their recurrent parents and carried the null allele at the Wx-D1 locus. In each generation, the Wx-D1 locus was identified by a PCR-based DNA marker and the agronomic traits were examined in progeny plants. The results from this study indicate that the use of backcrossing with a PCR-based DNA marker was useful in waxy wheat breeding. These partial waxy wheat lines can be used in field production.展开更多
Genetic analysis of yield and yield components were carried out on three parental clones of Coffea canephora Pierre and their controlled hybrid progenies. There is a possibility to estimate coffee yield capabilities i...Genetic analysis of yield and yield components were carried out on three parental clones of Coffea canephora Pierre and their controlled hybrid progenies. There is a possibility to estimate coffee yield capabilities in simply via the easier measuring traits of yield components since significant correlation between them were detected. We found that among parental show very few significantly differences of all observed characters and even not found between the overall mean of the descendants and their donor parents, whereas some particular descendants show higher values rather than their donor parent in one or more characters. Increased value between the best parent to the best descendent were detected varies from zero to 102%. This situation suggests the difficulty to find out the optimum yield in a single plant by accumulating all of yield components that actually can increase 143% to 278% from actual to potential yields. In addition, observed characters among population were also actually found highly varies from 159% in out-turn in population B to 28,333% in number of productive branch among population A. Low heritability （h2） that generally found in quantitative traits due to polygenic control was present in our studies in almost all characters observed. Therefore, selection for actual high yielding through conventional breeding will not efficient, and more convincing the power of selection using molecular markers to assist for cumulate additive effects in a single genotypes that resulted of high yielding in the future.展开更多
The half-smooth tongue sole Cynoglossus semilaevis is an important cultured marine fish and a promising model fish for the study of sex determination. Sex-specific genetic linkage maps of half-smooth tongue sole were ...The half-smooth tongue sole Cynoglossus semilaevis is an important cultured marine fish and a promising model fish for the study of sex determination. Sex-specific genetic linkage maps of half-smooth tongue sole were developed with 567 mark- ers （565 microsatellite markers and two SCAR markers）. The parents and F1 progeny （92 individuals） were used as segregating populations. The female map was composed of 480 markers in 21 linkage groups, covering a total of 1388.1 cM, with an average interval 3.06 cM between markers. The male map consisted of 417 markers in 21 linkage groups, spanning 1480.9 cM, with an average interval of 3.75 cM. The female and male maps had 474 and 416 unique positions, respectively. The genome length of half-smooth tongue sole was estimated to be 1522.9 cM for females and 1649.1cM for males. Based on estimations of map length, the female and male maps covered 91.1% and 89.8% of the genome, respectively. Furthermore, two female-specific SCAR mark- ers, f-382 and f-783, were mapped on LG15f （linkage group 15 in female maps）. The present study presents a mid-density genetic linkage map for half-smooth tongue sole. These improved genetic linkage maps may facilitate systematic genome searches to identify quantitative trait loci （QTL）, such as disease resistance, growth and sex-related traits, and are very useful for marker-assisted selection breeding programs for economically important traits in half-smooth tongue sole [Current Zoology 59 （1）： 99-108, 2013].展开更多
基金This work was supported by the grant from the National High Technology Research and Development Program of China (No. 2004AA212130).
文摘To improve agronomic traits of partial waxy wheat, crossing between Chinese Baihuomai and wheat cultivars PH85-16, Jinan 17, and Yannong 15 was performed. The progeny plants were further backcrossed to these cultivars as recurrent parents for five generations. To get homozygous plants with the null allele at the Wx-D1 locus, self-pollination was carried out in the BC5F1 generation. Through another three generations, 6 partial waxy wheat lines were obtained, which had similar agronomic performance as their recurrent parents and carried the null allele at the Wx-D1 locus. In each generation, the Wx-D1 locus was identified by a PCR-based DNA marker and the agronomic traits were examined in progeny plants. The results from this study indicate that the use of backcrossing with a PCR-based DNA marker was useful in waxy wheat breeding. These partial waxy wheat lines can be used in field production.
文摘Genetic analysis of yield and yield components were carried out on three parental clones of Coffea canephora Pierre and their controlled hybrid progenies. There is a possibility to estimate coffee yield capabilities in simply via the easier measuring traits of yield components since significant correlation between them were detected. We found that among parental show very few significantly differences of all observed characters and even not found between the overall mean of the descendants and their donor parents, whereas some particular descendants show higher values rather than their donor parent in one or more characters. Increased value between the best parent to the best descendent were detected varies from zero to 102%. This situation suggests the difficulty to find out the optimum yield in a single plant by accumulating all of yield components that actually can increase 143% to 278% from actual to potential yields. In addition, observed characters among population were also actually found highly varies from 159% in out-turn in population B to 28,333% in number of productive branch among population A. Low heritability （h2） that generally found in quantitative traits due to polygenic control was present in our studies in almost all characters observed. Therefore, selection for actual high yielding through conventional breeding will not efficient, and more convincing the power of selection using molecular markers to assist for cumulate additive effects in a single genotypes that resulted of high yielding in the future.
文摘The half-smooth tongue sole Cynoglossus semilaevis is an important cultured marine fish and a promising model fish for the study of sex determination. Sex-specific genetic linkage maps of half-smooth tongue sole were developed with 567 mark- ers （565 microsatellite markers and two SCAR markers）. The parents and F1 progeny （92 individuals） were used as segregating populations. The female map was composed of 480 markers in 21 linkage groups, covering a total of 1388.1 cM, with an average interval 3.06 cM between markers. The male map consisted of 417 markers in 21 linkage groups, spanning 1480.9 cM, with an average interval of 3.75 cM. The female and male maps had 474 and 416 unique positions, respectively. The genome length of half-smooth tongue sole was estimated to be 1522.9 cM for females and 1649.1cM for males. Based on estimations of map length, the female and male maps covered 91.1% and 89.8% of the genome, respectively. Furthermore, two female-specific SCAR mark- ers, f-382 and f-783, were mapped on LG15f （linkage group 15 in female maps）. The present study presents a mid-density genetic linkage map for half-smooth tongue sole. These improved genetic linkage maps may facilitate systematic genome searches to identify quantitative trait loci （QTL）, such as disease resistance, growth and sex-related traits, and are very useful for marker-assisted selection breeding programs for economically important traits in half-smooth tongue sole [Current Zoology 59 （1）： 99-108, 2013].
