共查询到20条相似文献,搜索用时 546 毫秒
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HVI90 0大容量纤维测试仪是一种相对测试仪器 ,目前使用的校准棉样有两种 :美国农业部 HVI校准棉样 (简称 HVICC)、国际校准棉样 (简称ICC)。测试结果表明用 ICC校准的强度值低于用HVICC校准的强度值。余楠等 ( 1 998)通过分析德国不来梅国际纤维对比试验结果 (表 1 )给出了两者间的换算关系 :HVICC标准强度值≈ 1 .2 9× ICC标准强度值。这一换算关系的提出 ,有利于正确评价进口原棉与国产棉的品质差距 ,并确当估计当今的育种成果。余楠等 ( 1 998)提出的换算系数 1 .2 9是将表 1中 1 7个样品的 HVICC强度平均值与 ICC强度… 相似文献
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HVI棉纤维大容量测试仪检测指标解析 总被引:6,自引:1,他引:5
目前,快速、自动化、大容量棉花测试仪器应首推Uster公司的HVI系统(HVI是棉纤维大容量测试仪英文名称HighVolume Inspection的缩写),该系统通过多台仪器联机对各项指标自动综合分析,能够全面判定试样性能并为生产工艺和后道产品品质预测提供有价值的信息,代表了当今世界棉花品质检验的最高水平和发展趋势。该仪器自80年代问世以来,至今已有近2000台套在世界各地广泛应用。其检验项目多、速度快、样本容量大和数据正确性高、客观性强的特点,使棉花质量检测手段从人工手感目测过渡为仪器检测。它由五个独立的基本组件组成,即长度/强力组件… 相似文献
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水稻粳型亲籼系粳型性的判别 总被引:11,自引:0,他引:11
摘要:选择均匀分布于水稻12条染色体上的100个微卫星标记对6个籼型、6个粳型测验种和10个待测粳型亲籼系的DNA遗传多样性进行了分析,结果表明,测验种DNA在籼粳分布上存在明显差异,表现在其粳型判别值(Dj)的变异范围为0.12~0.87, 籼型测验种的Dj值均低于0.25,粳型测验种的Dj值均高于0.75, Dj值可以用于粳型亲籼系粳型性的判别。根据Dj值大小,待测粳型亲籼系G2416-3、G2417-2-1、G3004-4和G3005-4-2属于偏粳型,G2505-1和G2605属于粳型。 相似文献
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Selecting an effective tester for evaluating the hybrid performance and heterosis of new inbred lines is crucial to ensure their accurate evaluation. Most sorghum breeding programs use at least two elite inbred line testers when evaluating new inbred lines. These testcrosses provide valuable information, but the specificity of inbred line testers may incorrectly characterize experimental lines that would combine well with other genetic backgrounds. Reducing this risk by increasing the number of preliminary testcrosses is limited in breeding programs by resource availability. Efficiently diversifying testcrosses may be accomplished through the use of F1 testers. Testcrosses made with F1 testers simultaneously evaluate inbred lines against two genetic backgrounds. In preliminary testcrosses, this may reduce the probability of incorrectly discarding new lines or improve the efficiency of preliminary testcrossing. The objective of this research was to compare two sorghum inbred line testers to their respective F1 as a tester for evaluating sorghum inbred lines (R-lines) in testcrosses for grain yield. The testers used were A.Tx623, A.Tx2752 and their F1 hybrid, A.Tx623/B.Tx2752. Data from testcross hybrids from 33 different inbred lines grown in three environments indicated that the F1 tester was comparable in accuracy and discriminatory efficiency to the inbred line testers. The results indicated that a single cross tester in sorghum can serve to effectively evaluate new germplasm. 相似文献
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水稻亚种间的亲和性研究 总被引:10,自引:0,他引:10
对160个亚种间F_1结实率的分析表明,籼稻 IR58和二九丰、粳稻秀水117和T8340具有较好的亚种间亲和性。43个粳稻品种分别与 IR58和二九丰测交,其成对 F_1的结实率随粳稻品种不同而出现 IR58/粳高于二九丰/粳、二九丰/粳高于 IR58/粳或两者相似的情形,其最大差值可达72.6个百分点。10个籼稻品种分别与秀水117和 T8340杂交,其F_1结实率均以秀水117/籼较高,成对F_1结实率的最大差值可达39.6个百分点。这表明不存在对亚种间品种均表现亲和性的“广亲和”品种,亲和性的广与狭只是相对的,既有一般亲和性,又有特殊亲和性。本研究发现4个受测品种的亲和性与色素基因之间不存在连锁或相关关系。 相似文献
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Simulation of the effect of pruning and topping on cotton growth using COTTON2K model 总被引:1,自引:0,他引:1
COTTON2K, like most other cotton production models, does not always adequately represent local growth conditions owing to the fact that it fails to take into account some indigenous cultivation practices. For instance, pruning and topping, a common practice for cotton cultivation in China is not included in the model simulation of COTTON2K. The objective of this research therefore was to: (1) modify COTTON2K source code and slot pruning and topping simulation switch on to the model, and (2) calibrate and validate the modified COTTON2K model with field data from pruning and topping cultivation practice. First, field collected data in 2003 and 2004 were compared between the treatments, with and without pruning and topping, and the COTTON2K source code updated with the ‘pruning and topping’ switch. This was followed by the calibration and validation of the updated model with field data and simulation of the effect of pruning and topping on cotton performance. It was noted from field observations that pruning and topping reduced total fruit sites, but at the same time, increased retained boll number, possibly due to significant reductions in abscised fruit sites. Though total dry matter production dropped, more dry matter allocation to reproductive organs, however, enhanced higher cotton lint yield in the pruning and topping treatment. Results of the modified model simulation showed that growth in the number of main-stem node ceased after topping. Furthermore, there was more biomass allocation to reproductive organs, such as green and open bolls under pruning and topping. Coefficient of determination above 0.8 for most of the growth factors was obtained in the calibration and validation processes under pruning and topping, a strong indication of the level of success of the model modification. 相似文献
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部分高油玉米自交系产量性状配合力分析 总被引:1,自引:0,他引:1
以来自中国农业大学的15份高油玉米自交系为被测系,以黑龙江省6个常用骨干自交系为测验种,采用NCII遗传交配设计,系统地比较分析15个高油玉米自交系产量性状的配合力。结果表明,高油玉米自交系BY812、BY815、GY798、GY237多数产量性状的GCA较高,就产量而言应视为优良自交系。高油系GY302、GY923、GY1007多数产量性状的GCA较低,用这些自交系做亲本,选育高产组合的概率不大。大多数高油系与81162、444间的单株产量总配合力效应值为正值,而与434、红玉米间的总配合力效应值多为负值,说明多数高油系的适宜的组配方向为Reid系统和唐四平头系统。高油系BY832、BY815与6个测验种间的总配合力效应值均为正值.是黑龙江省今后需重点应用的高油系。而GY302、GY462、GY923、BY807与6个测验种间的总配合力效应值均为负值,在黑龙江省难以组配优良杂交种,需进一步探索其杂优模式。 相似文献
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Cotton fabrics exhibiting superhydrophobic and antibacterial properties were prepared through a non-solvent induced phase separation method using hydrophobic poly(vinylidene fluoride) (PVDF) and its hybrids with photocatalytic zinc oxide nanoparticles (nano-ZnO) as surface modifying agents for cotton fabric. The effects of coagulating medium and temperature on microstructural morphology and surface hydrophobictity of the cotton fabrics were investigated by FE-SEM observation and contact angle measurement. Superhydrophobic cotton fabrics exhibiting water contact angle higher than 150 ° could be obtained by coating the fabrics with solutions of PVDF and nano-ZnO followed by coagulation in ethanol as non-solvent. This phenomenon is considered to be originated from both chemically hydrophobic PVDF layer and physical micro- and nano-bumps formed on the surface of cotton fabric, which are essential requirements for Lotus effect. Moreover, antibacterial properties could be synergistically obtained by utilizing photocatalytic effect of nano-ZnO. 相似文献