播期密度及氮肥运筹方式对冬小麦籽粒产量的影响   总被引：5，自引：5，他引：5  

屈会娟  李金才  沈学善  王永华  尹钧  王成雨 《中国农学通报》2006,22(9):141-141

通过不同播期、播种密度和氮肥运筹方式对不同冬小麦品种籽粒产量及构成因子影响的研究，探讨了通过调控播期、密度及氮肥运筹方式实现不同品种丰产高效的可能性。试验结果表明，播期、播种密度和氮肥运筹方式均显著影响小麦产量及产量构成因子，播期以10/15~10/22最为适宜，播种密度以120万/km2~240万/km2为宜，氮肥运筹方式以N210(3:5:2)最好，其次为N210(5:5)。保证供试小麦品种实现9000kg/hm2产量的高产途径为主茎和分蘖并重，适宜的产量结构为：4:4:4，即亩有效穗数39.4~44.4万，穗粒数35.3~40.0，千粒重40.2~45.8g。  相似文献   

转MvNHX1和MvP5CS基因棉花耐盐抗旱性比较与育种价值分析     

游朝  晁朝霞  姚正培  任燕萍  陈全家  曲延英  张桦 《棉花学报》2015,27(3):198-207

通过对花粉管通道法获得的T7转MvNHX1基因的10个棉花株系和转MvP5CS基因的3个棉花株系与对照非转基因棉花D5在温室内盐和干旱胁迫下的发芽率、生理生化指标以及田间花期干旱胁迫下农艺性状和纤维品质进行分析发现:温室内盐和干旱胁迫后,转基因棉花叶片叶绿素含量、脯氨酸含量均高于对照,而丙二醛含量低于对照;田间花期干旱胁迫下,2种转基因植株果枝数、有效果枝数、铃数、有效铃数、铃重、子棉、皮棉、衣分、子指和衣指均高于对照,说明转MvNHX1基因和转MvP5CS基因植株在干旱逆境下的产量高于非转基因;经花期干旱胁迫后,2种转基因棉花的纤维断裂伸长率、短纤维率、马克隆值和纺纱一致性指数优于非转基因棉花D5。综合分析表明:2种转基因棉花的耐盐抗旱性均有提高,其中转MvNHX1基因棉花的耐盐性优于转MvP5CS基因棉花植株,而转MvP5CS基因棉花植株的抗旱性优于转MvNHX1基因棉花植株。  相似文献   

A comparison of progeny from diallel crosses of diploid potato with regard to the frequencies of 2n-pollen grains   总被引：1，自引：0，他引：1  

Qu Dongyu  Zhu Dewei  M. S. Ramanna  E. Jacobsen 《Euphytica》1995,92(3):313-320

Summary Selection of diploid potato genotypes that produce high frequencies of 2n-pollen grains in different environments is an important requirement for analytic breeding as well as for true potato seed production. In this context, quantitative estimates of 2n-pollen formation were made in two type of diploid potato populations. One population set consisted of the progeny from diallel crosses of five well-known diploid potato clones (A=US-W 5293.3, B=US-W 5295.7, C=US-W 5337.3, D=US-W 7589.2 and E=772102-37). Another population set was obtained by pollinating three genotypes of Solanum phureja, IvP35, IvP48 and IvP101 with clones A, C and E. It was observed that the behaviour of the parental clones with respect to 2n-pollen grains formation in different environments, such as in Europe and China, was stable. The correlation coefficient between means of 2n-pollen grains frequency of combinations and percentage of genotypes with more than 5% 2n-pollen grains in a given combination were estimated and that between mean and maximum frequency of 2n-pollen grains formation in each combination. The results showed that the former coefficients were significant wheareas the latter were not. The combining ability analysis revealed variation in 2n-pollen grains formation between families. Specific combining ability (SCA) effects contributed much more than general combining ability (GCA) to the variation in 2n-pollen grains formation. The broad-sense heritability of 2n-pollen grains formation was estimated to vary between 0.45 and 0.53 and the narrow-sense heritability was calculated to be 0.15 and 0.20 in the two types of populations. This means that additive variance was relatively low. Two to four genes were estimated to control the inheritance of 2n-pollen grains formation.  相似文献   

Identification of QTLs associated with salt or alkaline tolerance at the seedling stage in rice under salt or alkaline stress     

Jing-long Liang  Ying-ping Qu  Chun-gang Yang  Xiao-ding Ma  Gui-lan Cao  Zheng-wu Zhao  San-yuan Zhang  Tao Zhang  Long-zhi Han 《Euphytica》2015,201(3):441-452

  相似文献   

多效农艺营养纸膜对番茄和黄瓜生育的影响   总被引：2，自引：0，他引：2  

郭富常  尹立荣 《华北农学报》1995,10(4):119-122

采用多效农艺营养纸膜覆盖栽培番茄、黄瓜对其生育与开花结实，土壤养分含量及微生物含量进行了调查。结果表明，营养纸膜覆盖的的比地膜覆盖的土壤有机质含量增加，植株的Ｔ／Ｒ值降低，促进了植株的生长和开花结实，而且土壤中的病原菌也得到很好的控制。  相似文献   

Factors influencing tissue culture responses of mature seeds and immature embryos in turf-type tall fescue   总被引：23，自引：0，他引：23  

Y. Bai  R. Qu 《Plant Breeding》2001,120(3):239-242

In an effort to optimize tissue culture responses of turf‐type tall fescue for genetic transformation, the effects of five culture medium supplements on tissue culture responses were investigated with immature embryos and mature seeds of an elite cultivar, ‘Coronado’, as explant tissues. For both explants, calli induced on 6‐benzylaminopurine (BAP)‐containing medium had significantly improved regeneration ability. The optimal concentration of BAP for the induction of regenerable callus from mature seeds was 0.1 mg/l. Thidiazuron also improved callus regeneration frequency of mature seeds. Casein hydrolysate, L‐proline and myo‐inositol improved callus induction of immature embryos but not mature seeds. They did not improve callus regeneration frequencies with either explant tissue. By simply slicing the mature seeds into two halves longitudinally, the callus induction frequencies, as well as the corresponding overall plant regeneration frequencies, were increased approximately three‐ to six‐fold in all three combinations of 2,4‐dichlorophenoxyacetic acid and BAP in callus induction media.  相似文献   

农用车底盘偏置转向轴驱动轮运动与动力特性试验     

宋树杰  瞿济伟  李翊宁  郭康权  周伟 《农业工程学报》2015,31(23):28-34

为研究农用柔性底盘偏置转向轴驱动轮的运动与动力特性,设计了基于偏置转向结构的实验台。该实验台是一种水平转盘式的电动驱动轮性能测试试验台,且转盘的回转轴与偏置转向轴同轴,通过对电动轮及其车叉的试验分析来获取驱动轮的动力与运动参数。利用MATLAB/SIMULINK建立试验台模型并模拟了试验过程;试制了试验台并应用Visual Basic开发了试验台记录软件。在额定转速下进行了不同加载量的性能试验并与模拟结果进行了比较。试验结果表明:加载不同载荷时,电动轮达到稳定转速平均时间稳定为0.667 s;承载载荷500 N时的转向力为77.24 N,且偏置轴转向力与载荷呈线性关系,验证了实验台的可行性及模型的有效性。该研究可为偏置转向轴驱动轮的转向及参数优化提供参考。  相似文献   

人工神经网络在冻土水盐空间变异与条件模拟中的应用比较   总被引：2，自引：2，他引：2  

屈忠义  陈亚新  杨靖宇 《农业工程学报》2007,23(7):48-53

该文利用人工神经网络的BP模型建立了具有类似普通Kriging(OK)法和条件模拟(CS)运算目标的人工神经Kriging(NK)方法，在黄河河套平原进行了耕地和盐荒地初冻期、最大冻深期和融通期土壤水盐时空变异性的模拟和估值，通过NK法与OK法、CS法模拟、估值、检验结果及3种方法的理论变异函数、统计参数与实验变异函数的对比，结果表明NK法在消除滑动平均影响方面优于OK法，并以类似于CS法的空间变异性进行模拟，而且NK法有自身独特的优点，它不需要协方差函数的估计和变异函数的推求，对于含有一定特异值和一维到三维空间的扩展有更强的适应性，是对空间变异性应用研究方法的一种补充，同时拓宽了ANN的应用领域，具学科融合的优势。  相似文献   

Long-term continuous cropping in the Pacific Northwest: Tillage and fertilizer effects on winter wheat, spring wheat, and spring barley production     

Stephen Machado  Steve Petrie  Karl Rhinhart  Annie Qu 《Soil & Tillage Research》2007,94(2):473-481

Conventional tillage winter wheat (Triticum aestivum) (WW)–summer fallow reduces soil productivity and increases soil erosion. Conservation tillage management, together with intensive cropping may have the potential to reverse these sustainability concerns. The objective of this study was to determine the effects of conventional tillage (CT) and no-tillage (NT) systems on grain yield of long-term annual cropping of monoculture WW, spring wheat (SW), and spring barley (Hordeum vulgare) (SB) grown with or without fertilizer, in the Pacific Northwest region of the USA. In unfertilized crops, grain yield of WW, SW, and SB was 15%, 25%, and 50% higher, respectively, in CT than in NT plots, an indication of the involvement of yield limiting factors under the NT cropping system. When fertilized, there were no significant differences in grain yield of WW. Yields of SW and SB, however, remained 21% and 15% higher, respectively, in CT than in NT, an indication that factors other than fertility were involved. These results suggest that in order for NT management to be widely adopted by area growers, the yield-limiting factors need to be addressed.  相似文献   

水稻土中铁氧化物的厌氧还原及其对微生物过程的影响   总被引：20，自引：3，他引：20  

曲东  张一平  Schnell S  ConradR 《土壤学报》2003,40(6):858-863

采用厌氧泥浆恒温培养实验 ,测定了添加 6种外源氧化铁后土壤中Fe(Ⅱ )和Fe(Ⅲ )浓度的变化 ,探讨了不同氧化铁的还原能力及其对土壤产H2 、产CO2 、产乙酸和产CH4 过程的影响。结果表明 :无定形氧化铁和纤铁矿易于被还原 ,两者的最终还原程度大体相同 ,但无定形氧化铁存在还原滞后现象 ;针铁矿、赤铁矿、Al取代针铁矿和Al取代赤铁矿难以被还原 ,表现出与对照相同的还原特征 ;铁还原能导致土壤中H2 和乙酸稳态浓度的降低 ,有效抑制了甲烷产生 ;添加Fe(OH) 3和纤铁矿后 ,Fe(Ⅲ )还原占总电子传递的贡献率由对照的 1 8.3 0 %增至 63 .3 2 %和 46.90 % ,而形成甲烷的电子传递贡献率由对照的 80 .92 %降至 3 5 .85 %和 5 2 .3 2 % ,Fe(Ⅲ )还原对电子的竞争消耗 ,使土壤产甲烷过程被强烈抑制  相似文献