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1.
提出了射水成穴播种的非接触播种新方法,设计并研制了自动射水成穴播种试验装置,通过土槽试验研究了射水成穴播种的可行性以及成穴的基本规律和合适的工作参数范围。成穴播种试验表明,在沙壤土条件下,当射水压力在1.8~2.0MPa、射水时间在0.6~1.0s时,可以实现射水成穴播种且能满足穴播的农艺要求。射水压力和射水时间对膜孔大小和穴孔深度有显著影响,射水压力和射水时间的交互作用也对膜孔大小和穴孔深度有显著影响。  相似文献   
2.
选用 9个普甜玉米 (ZeamaysL saccharataSturt)自交系作测验种 ,用新选育的 10个普甜玉米自交系作待测系 ,采用NCⅡ交配设计和相关分析的方法 ,对待测系的配合力测定中测验种最少数目进行研究。结果表明 :若对测验种加以筛选 ,被筛选出的测验种只用其中一个 ,就能较准确地测定待测系的产量一般配合力 (GCA) ;若对测验种不加筛选 ,则能够准确地测定待测系产量GCA的最少测验种数目为 3个。对 8个农艺性状进行测验种测定效果评价时 ,株高、生育期、穗重、穗长、穗粗、行粒数及千粒重对测验种的选择不太严格 ;而秃尖长对测验种的选择严格  相似文献   
3.
 选用表现较好的9个普甜玉米(Zea mays L. saccharata Sturt)自交系作测验种,用新选育的10个普甜玉米自交系作待测系,采用NCⅡ交配设计,对待测系配合力测定中的测验种进行筛选。结果表明:甜玉米自交系可筛选出用于测定甜玉米待测系的产量及农艺性状一般配合力的测验种;株高对测验种的选择不严格,而穗重、穗长、穗粗、行粒数、千粒重、生育期及秃尖长对测验种的选择较严格。  相似文献   
4.
将等效负荷直接加到提升臂上,完成拖拉机在线提升试验。减少试验人员,提高试验效率,增加安全性。  相似文献   
5.
Coffea canephora Pierre breeding in Côte d’Ivoire is based on indirect reciprocal recurrent selection (RRSi) using the Congolese and Guinean populations. In practice, the genotypes of each population (78 Congolese genotypes and 100 Guinean genotypes) are tested with several testers from the reciprocal population: two Guinean and three Congolese testers. These testers are heterozygous as C. canephora is a strictly outcrossing species. After a first cycle of RRSi, we judged the efficiency of these testers for yield, susceptibility to coffee leaf rust (SCLR) and hundred bean weight (HBW). All the testers discriminated the tested genotypes highly significantly (P < 0.01), even though differences were found in the degrees of discrimination. For yield and SCLR, no interaction between tested genotypes and testers was observed and correlations between test values obtained from different testers were significant or highly significant. Furthermore, test values of tested genotypes could be used to predict the yield and SCLR of between-population (BP) hybrids. Prediction was always more accurate with the best tester than with the mean of several testers. As opposed to yield and SCLR, HBW showed significant interactions between tested genotypes and testers and HBW of hybrids could not be predicted from the test value of the genotypes. We conclude that only one reciprocal tester can be used in the next cycles of RRSi applied to C. canephora. This will allow either a reduced cost of selection or increased selection intensity.  相似文献   
6.
曹庆云  颜惜玲  左建军  叶慧 《安徽农业科学》2011,39(24):15108-15109
设计了操作简便、成本低廉的粉化率测定仪教学模型,用于本科实验教学环节。实践结果表明,学生通过亲手操作熟悉实验流程,加深了对测定颗粒饲料粉化率的意义和原理的理解,在很大程度上节约了实验成本。  相似文献   
7.
为了优化谷物休止角圆盘式快速测试仪的结构,降低其系统误差,进一步提高测试精度与系统的可靠性,通过更换不同直径的试验圆盘,分析测试数据的变异情况及其稳定性,确定了最佳圆盘直径为28cm;通过分析谷物锥形状,并考虑到原始公式的沿用,提出探针的位置应在径向距圆周边缘10cm处。  相似文献   
8.
玉米摘穗辊试验台的设计和试验   总被引:8,自引:0,他引:8  
阐述了影响辊式摘穗装置工作性能的诸因素和卧辊式玉米摘穗试验台的设计要点。设计中考虑了进行单因素试验和多因素试验中调控各相关工作参数、国产主要玉米收获机卧辊式摘穗辊的装拆以及数据采集等各环节中的技术问题。通过试验分析了辊式摘穗机构在摘穗中对玉米穗啃伤的影响因素,确定了在辊型一定的条件下,摘穗辊转速是主要因素。  相似文献   
9.
采用NCⅡ设计,用3个自交系和2个单交种测定中综3号8个改良群体的一般配合力,结果表明,单交种测验效果优于自交系测验效果,大多数性状上2个单交种测定结果与5个测验种总体结果高度正相关;3个自交系测验结果与总体测验结果之间在产量和果穗性状上的相关性不显著,测验种一般配合力高低与测验效果呈不显著负相关。  相似文献   
10.
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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