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1.
Variation was investigated in 110 doubled haploid (DH) lines of wheat derived from wheat × maize crosses. Field observation revealed visible variations in 15 DH2 lines such as extreme dwarfism, low seed fertility, alteration of spike type and stripes. Six agronomic traits, i.e., heading date, spike number/ plant, culm length, spike length, seed fertility and grain weight were statistically analyzed in the DH2 and DH3 generations. Out of the 88 DH2 lines/DH3 groups, 26 %/64 % showed significant differences from the parental variety in the means of one or more traits. Ranges of the DH3 lines were larger than those of the DH2 lines, except for spike number/plant. Furthermore, analyses of variance within and between DH lines showed the presence of heterogeneity/heterozygosity in the DH2 lines/plants. These results indicated the occurrence of gametoclonal variation in the DH lines. It is considered that most of the variations detected were due to the colchicine treatment rather than to the 2,4-D treatment or in vitro culture. 相似文献
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利用芥蓝×青花菜DH群体构建AFLP连锁图谱 总被引:9,自引:2,他引:9
利用青花菜(Brassica oleracea var. italica) 与芥蓝(Brassica oleracea var. alboglabra) 杂交后代双单倍体(DH) 群体为材料, 通过AFLP技术构建了一个甘蓝类作物较高密度的遗传连锁图谱。该图谱包括9个主要连锁群及2个小连锁群, 总图距801.5 cM, 含337个AFLP标记, 标记间平均距离为3.6 cM,为甘蓝类作物基因定位、比较基因组学及重要经济性状QTL分析提供了一个框架图谱。 相似文献
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É. Darkó J. Fodor S. Dulai H. Ambrus A. Szenzenstein Z. Király B. Barnabás 《Journal of Agronomy and Crop Science》2011,197(6):454-465
To improve the abiotic stress tolerance of maize (Zea mays L.), doubled haploid (DH) plants were produced by in vitro selection of microspores exposed to tert‐butyl hydroperoxide (t‐BuOOH) as a powerful prooxidant This study investigated the tolerance of the progenies of t‐BuOOH‐selected DH lines to oxidative stress, cold and drought in controlled environment pot experiments by analyses of photosynthetic electron transport and CO2 assimilation processes, chlorophyll bleaching and lipid peroxidation of leaves. Our results demonstrated that the t‐BuOOH‐selected DH plants exhibited enhanced tolerance not only to oxidative stress‐induced by t‐BuOOH but also to cold and drought stresses. In addition, they showed elevated activities of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase and glutathione S‐transferase when compared with the DH lines derived from microspores that were not exposed to t‐BuOOH and to the original hybrid plants. The results suggest that the simultaneous up‐regulation of several antioxidant enzymes may contribute to the oxidative and cold stress tolerance of the t‐BuOOH‐selected DH lines, and that the in vitro microspore selection represents a potential way to improve abiotic stress tolerance in maize. 相似文献
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雪单3 号是利用双单倍体育种技术选育的春白萝卜新品种。母本ED0108A 是以梅花春萝卜× 白玉春萝卜进行花药培
养获得的DH 系为轮回父本,与不育系进行多次回交,转育成的雄性不育系。父本ED3128 是由迟花春萝卜× 天鸿春萝卜进行
花药培养获得的DH 系。该品种生育期60 d(天),植株开展度45 cm,裂叶,小叶11 对,叶片数20,叶簇平展,叶色深绿;
肉质根长圆柱形,白皮白肉,根长36 cm,横径7.1 cm,单根质量1.1 kg,高抗黑腐病、芜菁花叶病毒病、黄瓜花叶病毒病和花
椰菜花叶病毒病,抗霜霉病,群体整齐度高。每667 m2 产量4 000~5 000 kg。适宜在湖北、湖南、河南、山东等地区早春栽培。 相似文献
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[目的]检验绵山羊双羔素的免疫效果,提高中国美利奴羊的繁殖率,增加养羊的经济效益。[方法]应用绵山羊双羔素(睾酮-3-羧甲基肟·牛血清白蛋白),在新疆维吾尔自治区巩乃斯种羊场和新疆生产兵团76团分别免疫中国美利奴新疆型羊841只和军垦型羊3 502只。[结果]新疆型试验组产羔率为143.68%,对照组产羔率为125.10%,试验组比对照组提高产羔率18.58%;军垦型试验组产羔率为120.27%,对照组产羔率为105.05%,试验组产羔率比对照组提高15.22%。[结论]绵山羊双羔素可以提高中国美利奴新疆型和军垦型羊的产羔率。 相似文献
8.
以 2 ZT-935 型水稻插秧机为例,对不等角速双万向联轴器的输入轴 1与输出轴 3的运动关系进行了深入研究,比较精确地推导出轴1、3与中间轴2的夹角θ_1、θ_3(见图1)随转弯角度β变化的关系式,绘制了轴3的角速度ω_3、角加速度α_3的变化规律曲线图。为分析插秧系统的运动学、动力学问题和插秧质量提供了依据。 相似文献
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Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献