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991.
潍花6号是潍坊市农科院以79266做母本,鲁花11号为父本进行有性杂交,系统选育而成。经1998—2001年山东、河北两省区试、生产试验及高产示范表明,该品种具有早熟、高产稳产、果大仁大、出仁率高、耐贮性好、口味佳等突出特点,2001年和2002年分别通过山东、河北两省农作物品种审定委员会审定,是一个适于中国北方花生产区栽培的优质高产大花生新品种。  相似文献   
992.
不同紫花苜蓿品种引种试验研究   总被引:3,自引:1,他引:3       下载免费PDF全文
引进了国外8个苜蓿品种,在2003年至2005年对其产量、株高、营养价值、越冬率、越夏性、抗倒伏和经济效益等方面进行了比较,结果表明这8个苜蓿品种在郑州地区均表现了良好的适应性,其中WL232和猎人河是推广的首选品种。  相似文献   
993.
世纪之交我国棉花品种改良的科技发展   总被引:5,自引:0,他引:5  
近年来我国棉花生产急剧滑坡,起因是自然灾害,但缺乏突破性品种,或者说品种的遗传基础过于狭窄是内在的根本原因。我国棉花生产用种以自育品种为主的世代不会逆转。今后我国棉花品种改良的科技要点是:加强原始材料的收集和育种新亲本的创造;促进高新技术与常规育种的结合;常规育种技术亟待创新,重点是加强理论指导,方案要贴近生产实际;恢复诸如诱变及其与复合杂交相结合等方法研究;优质纤维将是遗传改良的重点性状。此外,品种立法也势在必行。  相似文献   
994.
主要作物新品种抗旱性鉴定指标的研究与应用   总被引:2,自引:0,他引:2  
针对我国北方干旱缺水,水资源日趋匮乏的特点,研究了农作物高产品种抗旱性鉴定方法、评价指标,编制了我国第一个有关农作物品种抗旱性鉴定的地方标准,完善了农作物品种的育种程序。河北省在全国率先开展了小麦和玉米等农作物新品种在参加区域试验的同时进行抗旱性鉴定试验。抗旱指数成为我国小麦和旱稻等作物的抗旱性鉴定指标和标准。  相似文献   
995.
Summary Improved crop varieties developed at experimental stations are intended for release for production in farmers' fields which are not necessarily the test sites. Therefore, it is important to measure the inter-site transferability of the crop variety. This study was undertaken to establish a statistical measure of inter-site transferability of a variety. Data on grain yield from two sets of multi-locational trials on barley and four sets of the wheat trials conducted by the Cereal Program, International Center for Agricultural Research in the Dry Areas, Syria, were analyzed to evaluate the inter-site transferability of the varieties. Genotype × environment interaction was significant and experimental errors were heterogeneous in each set of trials. Correlations between the slope (of linear regression of variety mean on location mean) and variety mean were significant (P < 0.01) in all trials. Correlations between the developed inter-site transferability statistic and the variety mean were significant (P < 0.05) in only two trials. Correlations between mean yield and probability of the inter-site transferability statistic were insignificant in all trials. The inter-site transferability statistic and the associated probability of the transferability may be used to select varieties which are high yielding as well as transferable to a new environment. The strong association of slope with mean yield restricted the scope of varietal selection but the introduced statistic did not suffer from this drawback.  相似文献   
996.
Summary Four leaf enzymes malate dehydrogenase (MDH), 6-phosphogluconate dehydrogenase (6PGD), peroxidase (PX) and aspartate aminotransferase (AAT) of 17 walnut cultivars and two pollen enzymes malate dehydrogenase (MDH) and 6-phosphogluconate dehydrogenase (6PGD) of 15 walnut cultivars were analysed using horizontal starch gel electrophoresis. Walnut cultivars of different origin exhibited different numbers of electrophoretic bands and also different relative mobility. Different activity levels and phenotypic groups were detected in studied enzyme systems. Pollen enzymes revealed higher variability than enzymes extracted from the leaves. 15 walnut cultivars were classified into 10 malate dehydrogenase phenotypic groups and 14 6-phosphogluconate dehydrogenase phenotypic groups based on pollen analyses. 17 cultivars were classified into 9 peroxidase phenotypic groups and 7 6-phosphogluconate dehydrogenase phenotypic groups based on analyses of leaves. All of the 15 walnut cultivars could be identified and distinguished with electrophoretic analyses of MDH and 6PGD from the pollen while only 10 cultivars were distinguishable with analyses of 6PGD and PRX from the leaves. No variability useful for cultivar identification was observed in MDH and AAT from the leaves.  相似文献   
997.
Summary Nineteen single-copy clones isolated from a PstI genomic library (cv. Maiden Plantain), and eight Vigna chloroplast DNA clones were used to probe total genomic DNA digests of 57 genotypes of Musa from India. The 19 genomic clones detected a total of 107 polymorphisms among the 57 genotypes. Principal coordinates and phenetic analyses of these data placed cultivars and species into distinct groups that were in general agreement with a previously published RAPD-based classification of these same plant materials. The 107 polymorphisms were sufficient to differentiate each clone from every other clone. Heterologous Vigna chloroplast DNA probes were used to characterize the cytoplasm of Musa cultivars and species. PCO analysis of these RFLPs were detected both within and between the generally recognized genome groups, indicating multiple hybridization pathways in the origin of hybrid clones. Data presented demonstrate that RFLPs are sufficiently abundant to classify Musa germplasm and that genetic relationships among Musa cultivars, based upon RFLP data, are in general agreement with relationships determined by analysis of morphology and RAPDs.  相似文献   
998.
Summary Soybean DNA fingerprints were analyzed by digoxigenin-labeled oligonucleotide probes complementary to simple repetitive sequences. The clearest and most polymorphic patterns were obtained with (AAT)6 as a probe, with which all 47 soybean cultivars tested could be distinguished. However, DNA fingerprints of individuals within cultivars showed the same pattern. Using (CT)8, (GAA)5 or (AAGG)4 as probes, clear polymorphic patterns among cultivars and accessions in the subgenus Soja (Glycine max and Glycine soja) were not observed, while quite different patterns were found in accessions in the subgenus Glycine. The results suggest that G. max and G. soja are closer in their genome structure. DNA fingerprints of reciprocal crosses between cultivars and accessions in the subgenus Soja were similar, and contained bands of both parents. In an F2 population from these crosses, such bands segregated in a Mendelian fashion.  相似文献   
999.
高翔  董健  张改生  雷玲  仝胜利 《中国农学通报》2005,21(5):121-123,163
对黄淮麦区的77个不同小麦品种高分子量谷蛋白亚基及亚基组成与蛋白质含量和沉降值之间的关系进行了研究,结果表明:Glu-1三位点的亚基等位变异共有13种,A1位点亚基1出现频率最高,为71.05%,亚基2*最低,仅为3.94%;B1位点亚基7 9和7 8相对频率最高,分别为43.42%和31.58%,亚基17 18出现频率最低,为1.32%;D1位点亚基2 12出现频率最高,为52.63%,亚基4 12最低,为3.16%。值得注意的是,优质亚基14 15和5 10,在B1和D1位点分别出现了较高的频率,为10.53%和31.21%。三位点亚基对蛋白质含量的效应分别表示为:1≥2*>Null,14 15≥17 18≥7 8>7>7 9>20≥6 8,5 10>2 12≥4 12。对沉降值的效应分别表示为:2*≥1>Null,14 15≥7 8>7≥17 18>7 9≥20>6 8,5 10>2 12≥4 12。在蛋白质含量水平上,亚基组成1、14 15、2 12,1、7 8、5 10,1、7、5 10和1、7 9、5 10相对较高;在沉降值水平上,亚基组成1、7 8、5 10和1、14 15、2 12相对较高。因此,研究认为三位点分别为1或2*、7 8或14 15、5 10是品质优良的最佳亚基组合。  相似文献   
1000.
针对目前形势,分析了农作物新品种引进推广中存在的主要问题,并提出加快新品种引进推广步伐的有效措施:加大资金投入,打好工作基础;根据市场需求,选准推广品种;搞好基地建设,提高种子质量;良种良法配套,挖掘增产潜力;创新推广方式,强化品种展示;规范品种引进,加强种子管理。  相似文献   
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