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941.
Tartary buckwheat (Fagopyrum tataricum) is a highly nutritious crop that is widely grown in Asia, but the flour contains a large portion of the hull if it is ground
with industrial processing since the hull is very hard to remove as it adheres to the testa layer of the groat. Rice-Tartary,
a particular type of Tartary buckwheat, has seeds with a loose hull and the presence of splits on the sides of the seeds that
make dehulling easily. The present study reports on the first attempt of crop improvement in Tartary buckwheat breeding through
hybridization. Hybrids were obtained by hybridization of crosses between Tartary buckwheat and Rice-Tartary. Additional crosses
were made among selected progenies of these crosses. Based on progeny analysis of the F1, F2, and F3, the character of Rice-Tartary, as exhibited as the presence of splits on the sides of the seeds, is controlled by one gene
which is homozygous recessive. A Tartary buckwheat breeding program has been conducted for 6 years based on these crosses.
Advanced lines with easy dehull and yield potential are at the stage of ready for yield trials. Production of easy dehulling
Tartary buckwheat in the future could boost Canada’s domestic and international markets. 相似文献
942.
Robert F. Park Henriette Goyeau Friedrich G. Felsenstein Pavel Bartoš Friedrich J. Zeller 《Euphytica》2001,122(1):113-127
Pathogenicity data from surveys of Puccinia triticina (formerly P. recondita f. sp. tritici) conducted in western Europe in 1995 were analysed to compare the structure of regional populations of the pathogen. Many
of the populations differed in phenotypic diversity and pathotypic composition, even though they occurred within a single
epidemiological unit, suggesting that local factors may influence the establishment and propagation of individual pathotypes
in the regional populations. Neighbouring regions were more similar than distant regions, and all regions shared at least
one pathotype, except populations in northern Italy and Scotland. A high degree of similarity was found between populations
in northern France and Great Britain, providing strong evidence of free movement of inoculum between these regions. Resistance
genes were postulated for a selection of 91 wheat cultivars, representing those most commonly grown in western Europe in 1995.
Thirteen cultivars lacked detectable seedling resistance genes and the remaining 78 possessed from one to three resistance
genes; those detected were Lr1, Lr3a, Lr10, Lr13, Lr14a, Lr17b, Lr20, Lr26 and Lr37. The most commonly detected resistance gene was Lr13, which was present singly or in combination with other resistance genes in 48 cultivars (53%). The gene Lr14a was detected in 18 cultivars, Lr26 was present in 16 cultivars. The role of host selection in the composition of the regional populations of P. triticina in western Europe in 1995 was difficult to assess on the basis of the results obtained, since virulence data were not available
for Lr13 and Lr14a.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
943.
Two wide hybrids, Diplotaxis erucoides (2n = 14) × Brassica rapa (2n = 20) and B. maurorum (2n = 20) × B. rapa, were developed using the sequential ovary–ovule culture. Reciprocal crosses failed, possibly as a consequence of strong
unilateral incompatibility. The F
1 hybrids in each combination were completely male sterile and morphologically intermediate to the respective parents. DNA
marker polymorphism and chromosome counts confirmed their hybrid nature. High frequency of bivalents in the F
1 and the presence of trivalents/quadrivalents in the derived amphiploids suggested genomic duplications and homoeology of the
parental genomes. Up to three homoeologous pairs between the D. erucoides (DeDe) and B. rapa (AA) genomes, and one between B. maurorum (BmBm) and B. rapa genomes were observed. Successful synthesis of the F
1 hybrids and amphiploids of B. rapa with D. erucoides and B. maurorum, and allosyndetic chromosome pairing are expected to permit introgressions of desirable loci into the cultivated Brassica
germplasm, especially for resistance to Alternaria
brassicae and Albugo candida. 相似文献
944.
Raquel Sánchez-Pérez Encarnación Ortega Henri Duval Pedro Martínez-Gómez Federico Dicenta 《Euphytica》2007,155(3):381-391
The inheritance of 16 important agronomic traits and its relationship were studied for four years in a population of 167 almond
[P. dulcis (Mill.) D.A. Webb] seedlings obtained from a cross between the French selection ‘R1000’ (‘Tardy Nonpareil’ × ‘Tuono’) and
the Spanish cultivar ‘Desmayo Largueta’. For some traits (blooming and leafing date) descendants segregated between the value
of both progenitors, meanwhile for others the mean of the offspring was lower (bloom density, productivity and ripening date)
or higher (in-shell/kernel ratio and double kernels). As expected, kernel bitterness and self-incompatibility behaved as monogenic
traits. Some important correlations between traits were detected. The implications of the transmission and the correlation
of these traits in the breeding programmes are discussed. 相似文献
945.
Summary Interspecific hybrids have been obtained in an incompatible cross between Glycine max and G. tomentella through the in vitro culture of hybrid embryos. The percentage of successful pod setting in the crosses averaged 12.8% but there were marked differences depending on the soybean cultivar used as the female parent. Hybrid embryos at globular to heart stages were extracted from the embryo sac 15–25 days after pollination and cultured in vitro. Hybrid plants were successfully obtained by culturing the embryos on B5 medium supplemented with 0.1 mg/l IBA followed by culture on B5 medium supplemented with 0.1 mg/l TBA plus 0.25 mg/l 2-iP. The F1 plants resembled the wild male parent in growth form, but had an intermediate leaf shape between that of the parents. 相似文献
946.
947.
948.
Ho-Young Ban Dana Sim Kyu-Jong Lee Junhwan Kim Kwang Soo Kim Byun-Woo Lee 《Journal of Crop Science and Biotechnology》2015,18(4):265-272
It would be preferable to use a reliable crop growth model for studies on climate change impact assessment. The objectives of this study was to evaluate simulation performance for two maize models, including CERES-Maize and IXIM models, included in the DSSAT model (version 4.6) in terms of phenology and yield. Two early maturing cultivars, Chalok#1 and Junda# 6, were grown under controlled environment in plastic houses at Suwon, Korea. Each cultivar, which was sown at four different date in 2013 and 2014, was subjected to four sets of temperature conditions including ambient (AT), AT+1.5°C, AT+3°C, and AT+5°C. In simulations of phenology under given conditions, the anthesis date and grain filling ratio were underestimated, especially when temperature was unusually high, e.g., in 2013. The maize models also had poor accuracy in grain yield, which resulted from the fact that these models had relatively large errors in simulation of kernel number and kernel weight under elevated temperature conditions. In addition, both models were not able to simulate the drastic decrease of kernel number due to heat stress around flowering periods. These results indicated that two maize models would need improvements in simulation of crop response to supra-optimal temperature before they would be used to assess the impact of the climate change on maize yield. This studies merits further study to improve algorithms in phenology simulation at supraoptimal temperature. 相似文献
949.
Hoy-Taek Kim Yutaka Hirata Yong-Uk Shin Hae-Sung Hwang Jeong-Hwan Hwang Il-Sheob Shin Dae-Il Kim Sang-Jo Kang Hyun-Jung Kim Dong-Young Shin Ill-Sup Nou 《Euphytica》2004,138(1):73-80
The pear cultivar ‘Osa-Nijisseiki’ (S2Ssm
4; sm = stylar-part mutant) has been used as a parent to breed self-compatible cultivars that produce excellent fruits. However,
determination of the self-compatibility of ‘Osa-Nijisseiki’ offspring requires a lot of time, 6 years or more, by conventional
cross breeding. We have designed a rapid reliable method for the identification of self-compatible varieties of ‘Osa-Nijisseiki’
offspring based on the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) with S-allele specific
restriction endonucleases. By using this method, 8 self-compatible varieties were selected among 16 selections resulting from
a cross between the self-compatible cultivar ‘Osa-Nijisseiki’ (S2Ssm
4) and the self-incompatible cultivars ‘Niitaka’ (S3S9), ‘Whasan’ (S3S5), ‘Chuwhangbae’ (S4S6). The S-genotypes of 16 ‘Osa-Nijisseiki’ offsprings were also determined.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
950.
QTL mapping and associated marker selection for the efficacy of green plant regeneration in anther culture of rice 总被引:3,自引:0,他引:3
Anther culturability of rice is a quantitative trait controlled by nuclear‐encoded genes. The identification of quantitative trait loci (QTL) and associated marker selection for anther culturability is important for increasing the efficiency of green plant regeneration from microspores. QTL associated with the capacity for green plant regeneration in anther culture of rice were mapped on chromosomes 3 and 10 using 164 recombinant inbred (RI) lines from a cross between ‘Milyang 23’ and ‘Gihobyeo’. The quantitative trait locus located on chromosome 10 was detected repeatedly when three anther culture methods were applied and was tightly linked to the markers, RG323, RG241 and RZ400. Associations between these markers and the efficacy of green plant regeneration in 43 rice cultivars and two F2 populations, ‘MG RI036’/‘Milyang 23’, and ‘MG RI036’;/‘IR 36’ were analysed. One of these markers, RZ400, was able to identify effectively genotypes with good (> 10.0%) and poor (< 3.0%) regenerability, based on the marker genotypes in the cultivars and two F2 populations. This marker enables the screening of rice germplasm for anther culturability and introgression into elite lines in breeding programmes. 相似文献