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1.
Experiments were undertaken to identify an efficient method of selection for yield in early segregating generations of narrow-leaf lupin crosses. A first series of experiments involved simulation of F2 populations with mixtures of ten cultivars and advanced breeding lines. The performance of genotypes in mixtures sown at different densities was compared with their monoculture [commercial density) yields m the same and the following year. These comparisons provided a basis for assessing the value of different planting designs and different selection criteria in early generation selection for yield. Correlated monoculture yield responses to simulated selection for single plant yield were similar for the honeycomb design and standard selection procedures at both low and commercial densities. These responses were much higher than that for grid selection in a low density population. Correlated monoculture yield responses to selection for other plant characters were substantial only for flowering time and number of pod bearing branches under certain conditions. These responses were greatest for selection in a low density mixture and in the year following selection. A procedure involving selection of the earliest flowering plants and selection within this group of plants with the highest number of pod bearing branches should be an effective approach to early generation yield selection in the narrow-leaf lupin.  相似文献   
2.
Summary The effectiveness of the honeycomb selection method for yield in spring wheat (Triticum aestivum L.) was evaluated using progenies from two wheat crosses, Glenlea x NB131 and Glenlea x Era. Honeycomb selection was carried out in the F2 and F3 generations, grown at the University of Manitoba in the summers of 1980 and 1981, respectively. In both generations, divergent selection was made for both high and low yield. Plants selected in the F3 generation were entered in an F4 yield test in the summer of 1982. Results of the experiment showed that honeycomb selection for yield in the F2 and F3 generations was effective in identifying parents of high- and low-yielding lines. F3 plants from highyielding F2 selections gave higher yields than those from low-yielding F2 selections by 11.5% and 13.0% for Glenlea x NB131 and Glenlea x Era crosses, respectively. The F4 yield test showed that high yielding selections from both crosses significantly outyielded by 8.9% low yielding selections and by 14.4% the unselected composite lines. It is concluded that the honeycomb selection method can be used for early generation selection in spring wheat.  相似文献   
3.
硅肥生产技术综述   总被引:2,自引:0,他引:2  
综述了国内外硅肥发展概况以及粉煤灰硅肥、高炉渣硅肥的生产工艺。分析了国内利用粉煤灰、高炉渣生产硅肥发展缓慢的原因,并指出了今后对粉煤灰硅肥、高炉渣硅肥研究的重点。最后评估了利用粉煤灰、炼铁炉渣开发硅肥的经济效益和社会效益,这将为粉煤灰、高炉渣综合利用开辟提供有价值的参考。  相似文献   
4.
分别采用滤纸扩散法和试管二倍稀释法测定了意大利蜜蜂陈年巢脾(已使用3年)水提液和醇提液对金黄色葡萄球菌、表皮葡萄球菌、铜绿假单胞菌、乙型溶血性链球菌、肺炎链球菌的抑制作用和抑菌效果。结果表明,意大利蜜蜂陈年巢脾水提液和醇提液均对试验菌株有良好的抑制效果,且醇提液抑菌效果优于水提液。  相似文献   
5.
本机采用电子时控电路在巢框线上直通8A 左右电流,使框线埋入巢础中。每框埋线约需2秒钟,埋1万框线耗电0.44度,快速、省电,且质量优越。同时还可用作废脾快速卸框和提供2~13V 直流电源蓄电池充电等.整机体积700×380×90mm,造价低,操作简便。  相似文献   
6.
不同洗涤蜂窝煤灰渣对污染土壤中铅的稳定作用研究   总被引:1,自引:0,他引:1  
蜂窝煤灰渣具有稳定污染土壤中铅的作用,但可增大土壤pH和电导率(EC)。将蜂窝煤灰渣经过水洗和稀盐酸酸洗后加入铅污染土壤(1000mg·kg-1Pb),研究了不同处理灰渣对铅有效性和土壤性质的影响。结果表明,灰渣经水洗和酸洗后,其pH(分别下降1.94、3.70)和电导率(0.785、0.890mS·cm-1)明显下降,重金属有效性和全量也有一定程度的下降。水洗和酸洗灰渣加入土壤后,土壤磷有效性有一定的上升。污染土壤在未加磷条件下加入原灰渣、水洗灰渣和酸洗灰渣后,DTPA-Pb含量分别下降67.2、195、117mg·kg-1,加磷情况下加入这3种灰渣土壤DTPA-Pb含量分别降低102、91.8、86.8mg·kg-1,各处理与对照的差异均达到0.05的显著水平。连续提取的结果表明,不同处理对土壤铅形态的影响不明显。  相似文献   
7.
【目的】寻找合适的二氯喹啉酸和莠去津吸附剂,减轻其残留对农作物产生的药害。【方法】用甲醇淋洗添加了二氯喹啉酸或者莠去津的吸附剂(土壤和吸附剂混合物),淋洗液浓缩后经高效液相色谱检测分析。【结果】吸附剂单独使用时,不同粒径的活性炭(F280、F380、F580)对二氯喹啉酸和莠去津吸附率均达到80%以上,表现出良好的吸附性。吸附剂与土壤混合处理后,F580活性炭对二氯喹啉酸和莠去津吸附率分别为73.85%和59.49%,效果良好。【结论】活性炭F580可以有效地吸附水和土壤中的二氯喹啉酸和莠去津,具有实际应用和推广价值。  相似文献   
8.
新型轻质家具材料-木质材料强化蜂窝纸芯复合板的研制   总被引:3,自引:1,他引:2  
选用木质材料强化蜂窝纸芯中蜂窝单元的边长、纤维板支撑条的厚度以及强化蜂窝纸芯的拉伸率作为试验因子,探讨这三个因子对复合板力学性能的影响。试验结果表明,蜂窝单元的边长对板材MOR、MOE和平面抗压强度有显著性影响,支撑条厚度对MOE有显著性影响,拉伸率对板材力学性能无显著性影响。  相似文献   
9.
A series of carbon-honeycomb monoliths from kenaf natural fibers (KNF) have been prepared and characterized. Firstly, KNF were physically mixed with polyvinyl acetate (PVA) as a binder and next the mixture was extruded through a die to form disc type monoliths. After the extrusion, the monoliths were dried, carbonized and, finally, physically activated with synthetic air at different temperatures (350-550 °C). The carbon-honeycomb monoliths were characterized by N2 adsorption at −196 °C, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). The experimental results indicate that the method proposed in this work was suitable for the synthesis of solid carbon monoliths with the presence of large meso- and macropores like long parallel and straight canals extended through their structure. MIP data and SEM images illustrate an evident and progressive aperture of the blocked parallel channels with an increase of the activation temperature.  相似文献   
10.
分别研究了不同硝化细菌浓度(0、20、60、120 mL/100 L)和不同微生物滤料(珊瑚石、锅炉煤渣、牡蛎壳)对养殖水中氨氮处理效果的影响。结果显示,添加硝化细菌后,水体中的氨氮浓度呈现下降趋势,在8~12 h出现极低值后,开始上升,但上升速度较慢;随着水体中硝化细菌添加量的增加,水体中的氨氮浓度下降速度加快;水体中亚硝酸氮浓度呈现先上升后下降的趋势,并在4~6 h出现极高值,然后迅速下降,且硝化细菌添加量越高,下降速度越快。硝化细菌对以珊瑚石和锅炉煤渣为滤料的养殖水体中氨氮和亚硝酸氮的处理效果显著优于牡蛎壳,但珊瑚石和锅炉煤渣之间无显著差异。综合试验结果,应急水质处理时,硝化细菌菌剂的添加量以一次60 mL/100 L(或以活菌计数为1.2×109个/100 L)、间隔24 h添加1次为宜;经过脱硫筛选之后的锅炉煤渣可以作为循环水养殖用滤料。  相似文献   
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