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长江流域小麦地方品种农艺性状多样性分析 总被引:2,自引:0,他引:2
为了发掘可供湖北省小麦育种利用的优异遗传资源,以长江流域的477份小麦地方品种为材料,对其农艺性状表现进行考察和分析,并对不同生态区之间小麦地方品种的农艺性状进行了比较.结果表明,长江流域小麦品种农艺性状存在丰富的遗传变异:植株总体偏高,平均为122.10 cm,变幅为67~160 cm,变异系数达15.14%;小穗数较少,平均为19个,变幅为11~28个,变异系数为14.13%;穗粒数平均为34粒,变幅为7~62粒,变异系数为25.25%,部分材料穗粒数较多,大于60粒;播种到抽穗平均156 d,变幅为140~175 d,变异系数为4.16%;千粒重水平中等,平均为37.12 g,变幅为15.72~57.66 g,变异系数达21.56%.从这些地方品种中可筛选出一些单一农艺性状优良的材料.多重比较结果表明,7个生态区地方品种的农艺性状间,主穗长、主穗小穗数、穗粒数、穗粒重、千粒重差异不显著,其余性状差异显著. 相似文献
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Bean fly is a significant pest of common bean in semi-arid areas of East Africa. Apart from inadequate moisture in the dry land, bean fly simultaneously contributes negatively thereby adversely affecting bean productivity. The objectives of this study were to (1) identify sources of resistance to bean fly available in landraces, (2) confirm stability of host plant resistance in drought stress and (3) determine the effect of drought stress and seasonal variation on common bean genotypes in relation to bean fly attack for adaptability to the semi-arid areas of East Africa. Sixty four genotypes including landraces, bean fly resistant lines and local checks were evaluated for seed yield, 100-seed weight, days to maturity, plant mortality and pupae in stem in an alpha lattice design with two replications. This was under drought stressed (DS) and non-stressed (NS) environments and two treatments (insecticide sprayed and natural infestation) for three cropping seasons between 2008 and 2009. Genotypes differed in their reaction to natural bean fly attack under drought stressed (DS) and non-stressed (NS) environments over different cropping seasons. However, the effect of bean fly appeared to vary between the long rains (LR) and short rains (SR). It was observed that an increase in number of pupae per stem resulted in a higher plant mortality. The range of seed yield was from 345 to 1704 kg ha−1 under natural infestation and from 591 to 2659 kg ha−1 under insecticide protection. Seed yield loss ranged from 3 to 69%. The resistance of most of the bean fly resistant lines seemed to break down in presence of DS owing to their dismal performance. Screening of genetic resources in common bean to breed for host plant resistance to bean fly offers high potential of success if researchers take full advantage of the diversity available within the landraces. 相似文献
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D.?Gauchan M.?SmaleEmail author P.?Chaudhary 《Genetic Resources and Crop Evolution》2005,52(3):293-303
Market-based incentives are one means of encouraging farmers to grow landraces that are also of social value, thereby contributing to the conservation of crop genetic diversity on farms – and in principle, the cheapest. This study uses a participatory, market systems approach supplemented by baseline data from an ongoing project to analyze markets for rice landraces and modern varieties in Nepal. Nepal is located in the area of origin and diversity for Asian rice. With the exception of traditional Basmati rice (which is of high aromatic quality), most rice landraces are traded through small-scale informal channels. Traders earn higher profits handling modern varieties than landraces, with the exception of Basmati, which competes with modern varieties. The superior consumption qualities of Basmati are valued in markets, but conserving these landraces may not have great social value. Furthermore, farmers who grow Basmati are clearly better off than those who do not. Findings raise questions about the role of market-based incentives for conserving landraces on farms, the costs entailed in establishing a structure to generate them, and about efficiency vs. equity considerations in the design of conservation programs. 相似文献
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Salvador?Montes-HernándezEmail author Laura C.?Merrick Luis E.?Eguiarte 《Genetic Resources and Crop Evolution》2005,52(6):697-707
Squash (Cucurbita spp.) is a common component in traditional cropping systems in Mexico, mainly in the agroecosystem known as the “milpa”,
in which squash is cultivated in association with maize (Zea mays), the main crop. Using a questionnaire, 80 farmers were interviewed about crop production and selection practices in order
to understand how these factors affect genetic diversity of local squash populations. We found that the most of the farmers
who cultivate squash were elderly 59.8 ± 14.5 (mean ± SD; n = 78) years old. Squash varieties in the area were exclusively locally adapted landraces, and had not been replaced by modern
squash cultivars. Two cultivated squash species, C. argyrosperma ssp. argyrosperma and C. moschata, had been grown intercropped with maize by 97.5% of the interviewed farmers, but only 50.0% were still producing squash at
the time of the study. Farmers recognize typical characteristics of particular varieties within each of the local cultivated
squash species, and selection is directed to maintain their identity. Nearly two thirds of the farmers (62.0%) had exchanged
seeds of squash for planting, a practice that serves to increase genetic variability in the populations. All of the interviewed
farmers were conscious of the possible hybridization between the wild gourd (C. argyrosperma ssp. sororia) and their cultivated squash. Despite various natural and human managed factors identified as contributing to enhancement
of genetic diversity in these populations, results of the study show that genetic erosion of Cucurbita is likely in the region in the near future. 相似文献
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Edita Gregová Jiří Hermuth Ján Kraic Ladislav Dotlačil 《Genetic Resources and Crop Evolution》2006,53(5):867-871
The endosperm storage protein of 46 European wheat (Triticum aestivum L.) landraces and obsolete cultivars have been fractionated by SDS-PAGE to determine the composition of high molecular weight
glutenin subunits (HMW-GS) composition. It has been discovered that about 46% of the wheats were heterogeneous, comprising
2–11 different glutenin profiles. Eighteen of them were observed to be homogeneous. A total of 13 HMW-GS alleles, including
3 at the Glu-A1, 8 at the Glu-B1, and 3 at the Glu-D1 loci were revealed. HMW-GS null controlled by locus Glu-A1, subunits 7 + 8 by Glu-B1, and 2 + 12 by Glu-D1 predominated. However low frequented alleles such as 17 + 18, 20, 6, and 7 were observed. Furthermore, other new alleles
encoding HMW-GS at the locus Glu-B1 have been found in one of France cultivar (Saumur d’Automne). The glutenin-based quality score ranged from 4 to 10. 相似文献
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Magdalena Ruiz E.V. Metakovsky M. Rodriguez-Quijano J.F. Vazquez J.M. Carrillo 《Genetic Resources and Crop Evolution》2002,49(4):373-384
Fifty nine Spanish landraces of common wheat belonging to differentagrotypes were evaluated with four morphological spike characters and 11 seedprotein loci in order to study the level of agreement between the agrotypeclassification and the morphological and biochemical variation of the wheats. Asa result of the work 22 new gliadin alleles were found and 12 of them werecatalogued. Multivariate and cluster analysis performed on the two sets of data(morphological plus biochemical and biochemical only) showed that there was aclear relationship between seed protein composition and the wheat classificationfor the agrotypes Barbilla, Candeal andNegrete. For the other groups, agrotype classification was notconsistent with the variation for biochemical characters although, some allelesin common were found except for the Jeja type. Morphologicaltraits revealed that they could be useful as first step in discriminating amongagrotypes. In contrast, biochemical markers showed that genetic variation amongaccessions was higher than among agrotypes. The protein lociGli-B1,Gli-A2,Gli-D2 andGli-A1 were shown to be the mostpolymorphic and useful in discriminating between the accessions studied. 相似文献
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The variability of 14 landraces belonging to a Madrilean village historically specialized on melon cultivation, Villaconejos,
was evaluated based on 58 quantitative and qualitative morphological traits. These landraces were compared to a reference
array composed of 14 accessions which represented the main varieties cultivated in Spanish fields. Individual data related
to plant, fruit, seed and phenology have been analysed using a multivariate analysis. This analysis showed intra- and inter-varietal
diversity, as emphasized the most discriminant morphological traits in order to define similarities. Villaconejos accessions
were morphologically distinct from the reference accessions (RA). Only the landraces belonging to Piel de Sapo market class
showed common morphological affinities with the RA, grouping with them. The majority of Villaconejos traditional varieties
clustered in five different groups, with no RA within, showing distinctive morphological singularities not described previously.
Two of these groups showed some particularities in fruit traits, which are appreciated as quality marks for Spanish consumers.
These results indicate that these accessions must be conserved as valuable genetic resources to enrich the Inodorus genetic
bases for future breeding proposes worldwide. Furthermore, it should be considered the opportunity of promoting their cultivation
under the shelter of a Protected Geographical Indication as a high quality melon. Finally, the discovering of such a high
variability presented in a very small area, gives a clue for focusing, with an elevated probability of success, future surveys
in similar ancestral European villages which in the past times, also supplied more populated cities with their farming products. 相似文献