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51.
不同肥料配施对酸性土钙素活化及花生产量和品质的影响 总被引:1,自引:0,他引:1
为了揭示增施钙肥和不同肥料配施对沿海地区酸性土钙素增量及活化效应,于2015—2016年设置单施无机肥(CK_1)、无机肥/熟石灰配施(T_1)、无机肥—有机肥配施(CK_2)、无机肥—有机肥—熟石灰配施(T_2)、无机肥—有机肥—微生物肥配施(CK_3)、无机肥—有机肥—微生物肥—熟石灰配施(T_3)6个处理,研究了不同肥料配施对酸性土有效钙含量、花生植株性状、荚果产量和籽仁品质的影响。结果表明:CK_2和CK_3均在一定程度上提高酸性土中水溶性钙和交换性钙含量,0—20cm水溶性钙含量各生育期平均分别比CK_1提高48.13%和66.50%,交换性钙含量分别提高39.12%和60.88%。增施钙肥处理(T_1、T_2和T_3)能显著增加水溶性钙和交换性钙含量,但_T1处理对有效钙含量增加较少,而T_2和T_3处理增加幅度较大,其中T_3处理0—20cm水溶性钙和交换性钙含量各生育期平均比CK_3提高1.63,1.74倍,说明钙肥与有机肥和微生物肥配施能显著提高酸性土钙素活化度。不同肥料配施均提高了酸性土花生的主茎高、分枝数、主茎绿叶数、单株干物质重、叶面积指数和实收株数,增加了单株结果数和荚果饱满度,显著提高了荚果产量,并提高了蛋白质、总氨基酸和脂肪含量以及O/L值。其中T_3处理分别比CK_3、T_2、CK_2、T_1和CK_1增产14.38%,4.99%,18.31%,25.65%和52.52%,增产幅度最大,其籽仁品质也最优。增施钙肥并与有机肥和微生物肥配施能显著提高酸性土钙素活化度、有效钙含量、荚果产量和籽仁品质。 相似文献
52.
Seasonal critical concentration and relationships of leaf phosphorus and potassium status with biomass and yield traits of soybean
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Analysis of uppermost fully expanded leaves is useful to detect a deficiency of mineral nutrients such as phosphorus (P) and potassium (K) in soybean. Although, the leaf P or K status aids in fertilizer management, information on nutrient seasonal relationships with growth and yield traits at maturity are limited. To investigate this, soybean was grown under varying P or K nutrition under ambient and elevated CO2 concentrations. Results show significant relationships of the relative total biomass and yield‐related traits with the foliar P and K concentrations measured several times in the season across CO2 levels. However, the relationships established earlier in the season showed that the growth period between 25 and 37 d after planting (DAP), representing the beginning of flowering and pod, respectively, is the best for leaf sampling to determine the foliar P or K status. The leaf P and K status as well as the critical leaf P (CLPC) and K (CLKC) concentrations for traits such as seed yield peaked around 30 DAP (R2 stage) and tended to decline thereafter with the plant age. The CLPC and CLKC of seed yield indicate that the leaf P and K concentration of at least 2.74 mg g?1 and 19.06 mg g?1, respectively, in the uppermost fully expanded leaves are needed between 25 and 37 DAP for near‐optimum soybean yield. Moreover, the greatest impact of P and K deficiency occurred for the traits that contribute the most to the soybean yield (e.g., relative total biomass, seed yield, pod and seed numbers), while traits such as seed number per pod, seed size, and shelling percentages were the least affected and showed smaller leaf critical concentration. The CLPC or CLKC for biomass and seed yield was greater under elevated CO2 24–25 DAP but varied thereafter. These results are useful to researchers and farmers to understand the dynamics of the relationship of pre‐harvest leaf P and K status with soybean productivity at maturity, and in the determination of suitable growth stage to collect leaf samples. 相似文献
53.
旨在选育多四粒荚大豆品种,构建理想模型,为大豆高产超高产育种探索新途径。用spss 18分析‘汾豆96’生理生态特性,以椭圆叶形多四粒荚‘汾豆96’为主,结合34份披针叶形四粒荚材料,对其10项产量相关的农艺性状用逐步回归法构建理想模型。‘汾豆96’群体内四粒荚单株的存在率达85%以上,单株四粒荚最高达49个,占总荚数的30.25%,‘汾豆96’产量随四粒荚数的增加总体呈增加趋势。当R~2=0.939时,模型拟合最优:Y=-87.583+0.415X_1-5.155X_2+10.094X_3+13.459X_4。回归方程表明多四粒荚创新材料产量与生物产量(X_1)、株高(X_2)、百粒重(X_3)和主茎节数(X_4)呈显著线性回归关系。提升每荚粒数和选育多四粒荚品种,是高产超高产育种产量突破的新途径。大豆品种具备的理想模型是抗倒伏、多荚粒、适合机械化收获的短节间密荚类型。 相似文献
54.
H. Bindumadhava L. Sharma R. M. Nair H. Nayyar J.J Riley W Easdown 《Journal of Crop Improvement》2018,32(3):418-430
Increasing global air temperatures, along with rising CO2 levels, are causing concerns about reducing available freshwater resources and altering cropping patterns. They may influence overall growth and production pattern of crop plants. These likely changes would become major limiting factors for future sustainable food production largely in the tropics and subtropics. Thus, understanding physiological responses hold the key to determining the functional relationship between the environment and crop performance. We explore here the impact of rising CO2 on the growth and yield traits of a few selected high-temperature (HT)-tolerant mungbean lines, which we earlier screened for HT tolerance using a physiological assay under managed growth conditions. The HT-tolerant lines grown under elevated CO2 levels (550 and 700 μL L?1) showed a considerable improvement in growth rates (13.5%, 67.8%, and 46.5% in plant height, leaf area, and total dry matter, respectively) and pod and seed yield (48.7% and 31.7%, respectively), compared to local checks under the same environments. Interestingly, the symptoms of accelerated pod maturity were also observed in most of these lines. The outcome of the study would undoubtedly open up opportunities for increased yield potentials of legumes under the conditions of the warming climate and elevated levels of carbon dioxide. 相似文献
55.
菜豆荚斑驳病毒(Bean pod mottle virus,BPMV)是我国重要的检疫性有害生物,BPMV传入的风险随大豆进境数量增多而加大。本文针对菜豆荚斑驳病毒,以大豆种子提取液为材料,分别建立了TaqMan-MGB荧光定量IC-RTPCR和TaqMan-MGB荧光定量TC-RT-PCR快速检测方法。根据GenBank公布的BPMV外壳蛋白基因序列,选择其保守区域,设计1对特异性引物和1条TaqMan-MGB探针,测定了TaqMan-MGB荧光定量IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR方法的特异性和灵敏度,并将TaqMan-MGB荧光定量IC-RT-PCR、TaqMan-MGB荧光定量TC-RTPCR、IC-RT-PCR和TC-RT-PCR 4种检测方法的灵敏度进行比较。结果表明:所建立的两种检测方法特异性良好;TCRT-PCR的灵敏度为10-1倍病毒提取液原液;IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR灵敏度相当,为10-3倍病毒提取液原液;TaqMan-MGB荧光定量IC-RT-PCR灵敏度最高,为10-5倍病毒提取液原液,是IC-RT-PCR和TaqMan-MGB荧光定量TC-RT-PCR检测方法的102倍,是TC-RT-PCR检测方法的104倍;两种检测方法均能较好应用于实际大豆样品的检测。本文所建立的TaqMan-MGB荧光定量IC/TC-RT-PCR检测方法利用抗原特异性或试管非特异性捕捉病毒粒子,无需提取RNA,为进境大豆种子上BPMV的检测提供了稳定、快速、简便的技术依据,其较高的灵敏度和特异性具有较好的应用价值。 相似文献
56.
本研究对菜豆荚斑驳病毒大、小亚基编码的基因密码子进行了优化并人工合成了这两个基因,然后克隆到原核表达载体p ET-22b(+)中,通过转化大肠杆菌BL21(DE3)菌种并在IPTG的诱导下进行了成功表达,大亚基表达产物分子量为41 k D、小亚基表达产物分子量为22 k D,并制备出了大小亚基基因表达产物的抗血清。测试结果表明,优化后的CP的大、小亚基基因在37℃、1.0 mmol/L IPTG诱导下,3 h后得到了成功的表达,制备的两种抗血清特异性强、效价都达到1∶3.2×10~4,可以对BPMV CP 3个不同的区域同时进行检测,提高了检测的准确度。 相似文献
57.
Foliar fungal disease‐resistant introgression lines of groundnut (Arachis hypogaea L.) record higher pod and haulm yield in multilocation testing 下载免费PDF全文
Janila Pasupuleti Manish K. Pandey Surendra S. Manohar Murali T. Variath Premalatha Nallathambi Hajisaheb L. Nadaf Harikishan Sudini Rajeev K. Varshney 《Plant Breeding》2016,135(3):355-366
Introgression lines (ILs) of groundnut with enhanced resistance to rust and late leaf spot (LLS) recorded increased pod and haulm yield in multilocation testing. Marker‐assisted backcrossing (MABC) approach was used to introgress a genomic region containing a major QTL that explains >80% of phenotypic variance (PV) for rust resistance and 67.98% PV for LLS resistance. ILs in the genetic background of TAG 24, ICGV 91114 and JL 24 were evaluated for two seasons to select 20 best ILs based on resistance, productivity parameters and maturity duration. Multilocation evaluation of the selected ILs was conducted in three locations including disease hot spots. Background genotype, environment and genotype × environment interactions are important for expression of resistance governed by the QTL region. Six best ILs namely ICGV 13192, ICGV 13193, ICGV 13200, ICGV 13206, ICGV 13228 and ICGV 13229 were selected with 39–79% higher mean pod yield and 25–89% higher mean haulm yield over their respective recurrent parents. Pod yield increase was contributed by increase in seed mass and number of pods per plant. 相似文献
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60.
不同播期东农42产质量性状动态变化规律研究 总被引:2,自引:1,他引:1
本试验通过高蛋白品种东农42的六个播期试验,对品质性状和部分产量性状动态取样分析进行研究。确定不同播期对大豆产质性状影响,为指导大豆生产实践提供理论基础。试验通过对大豆东农42在六个不同播种时期的形态及产质量性状中的九个性状进行动态取样和测量,并通过EXCEL和SPSS10.0对试验数据进行统计分析。通过东农42不同播期动态规律研究表明:不同播期之间对品质性状、产量性状和形态性状影响均较大。随着播期推迟,品质性状蛋白质含量增加,油分含量减少;产量性状的单株荚数、鲜粒荚比降低,而鲜皮荚比升高;形态性状的主茎节数降低。但其它一些性状受环境光温条件和降水量影响较大,如株高,平均鲜粒重和平均鲜荚重等。本实验证明,黑龙江省哈尔滨地区大豆的适宜播种期在4月底至5月上中旬,如果播期太晚,会严重影响大豆产量。 相似文献