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91.
为合理利用绿豆种质资源,本研究以55份绿豆种质资源为材料,通过对其10个农艺性状进行因子分析及聚类分析。结果表明:10个农艺性状的变异系数为8.57%~47.19%,其中单株粒重变异系数最大,生育期变异系数最小。将10个农艺性状简化为结荚数因子、高度因子、粒数因子、粒重因子和生育期因子5个独立的主因子,该5个主因子可以反映原始信息的86.340%。经综合得分排序,评选出10份性状优良的绿豆种质资源。聚类分析将55份种质资源的10个数量性状分为3大类,类群I、类群II、类群III分别包括22份、7份、26份材料。结合综合评价和聚类分析认为,在黑龙江绿豆生产中,‘安绿8号’、‘佳木斯黄绿豆’、‘冀绿1号’可作为品种选育的改良亲本,也可大面积种植利用。 相似文献
92.
93.
In coping with increasing energy consumption and the consequential environmental pollution, green development is becoming an important part of social development. Since the inauguration of China’s Silk Road Economic Belt Initiative (BRI), economic cooperation between China and other countries along BRI has seen much growth. Therefore, it is of great significance to study the levels of green total factor productivity (GTFP) of the countries in the Silk Roads Economic Belt (B&R) and examine how these levels vary spatially and evolve temporally. In this paper, a panel regression analysis with DEA windows is used to study the spatiotemporal trends of the levels of GTFP. The results are: (1) The B&R countries have seen an increase in their overall levels of GTFP over time; (2) There are regional differences in the levels of GTFP, with higher efficiency in Western Asia and Central and Eastern Europe, and lower efficiency in Southeast and Central Asia; (3) The analysis of GTFP for countries in these regions shows that the efficiencies of most countries have been improving, with that of only a few countries have been decreasing; (4) By using regression analysis, we find that variables such as import, export, industrial structure, and urban affect the B&R countries with growing GTFP. 相似文献
94.
为了改善单叶片泵的运行特性,降低径向受力不均匀性,采用数值计算与试验相结合的方法分析了单叶片离心泵径向力的动态特性.研究了3个不同流量工况(0.6Qd,1.0Qd和1.4Qd)下径向力的变化规律,结果表明,单叶片离心泵叶轮叶片工作面与背面所受压差是径向力产生的主要原因,并在小流量工况下径向力达到最值.通过对试验与数值模拟结果的分析对比,提出了平衡单叶片泵径向力的新方法-叶片开缝,并在叶片包角方向上选取3个不同位置(0°,90°和270°)布置宽度为1.0 mm的缝隙,分析了不同开缝位置对径向力及泵外特性的影响情况.结果表明:当在叶片尾缘开缝时,对泵的外特性影响较小,并可以较大降低单叶片离心泵叶片工作面和背面的压差,减小叶轮径向受力情况,提高单叶片泵的可靠性和使用寿命. 相似文献
95.
扎鲁特旗山地草地土壤含水量动态与气候因子的关系 总被引:1,自引:1,他引:0
通过对内蒙古通辽市扎鲁特旗巴雅尔吐胡硕牧业气象站1983-2012年气象数据和山地草地土壤含水量数据分析,揭示土壤含水量的动态变化及其与气候因子之间的相关关系。结果表明,1983-2012年山地草地土壤各层(0-10、10-20、20-30、30-40、40-50和0-50cm)含水量均呈现逐渐降低的变化趋势,草地逐渐旱化;土壤含水量下降过程可以分为3个阶段,第1阶段为1983-1987年,该阶段土壤含水量在15%~30%之间波动,属于土壤含水量的较高阶段;第2阶段为1988-1999年,该阶段土壤含水量在5%~15%范围内波动,属于土壤含水量高(15%~30%)向低(2%~10%)过渡阶段;第3阶段是2000-2012年,该阶段土壤含水量在2%~10%范围内波动,属于土壤含水量较低阶段;土壤含水量与温度和日照时数呈负相关,与降水量、相对湿度、蒸散量呈正相关。 相似文献
96.
利用树轮学方法,以长白山雌雄异株植物红豆杉、山杨和水曲柳为研究对象,通过判定雌雄异株树种生长释放/抑制事件及其与气候因子的关系,以期揭示物种属性和性别因素对树木生长释放/抑制事件的影响及其对气候响应机制的差异性。结果表明:3种雌雄植株的生长释放事件大多发生在幼龄阶段,生理特征差异也可能导致不同雌雄植株发生生长释放事件的时间和频率存在一定差异性。性别因素对山杨和红豆杉雌雄植株的生长释放存在显著影响,山杨雌株和红豆杉雄株对外界环境干扰更为敏感,水曲柳雌雄株对环境干扰的响应差异不明显;山杨更易受到外界环境干扰发生生长释放事件;水曲柳植株发生生长释放/抑制事件可能与林窗干扰有关。红豆杉和山杨的生长释放事件与气候因子具有显著相关关系,红豆杉雄株与温度、降水则存在显著正相关关系(P0.05),山杨雄株与温度、降水则存在显著负相关关系(P0.05),山杨雌株与降水呈显著负相关关系(P0.05),植株的生长释放/抑制事件对气候的响应与树木径向生长--逐月气候因子的关系有所不同。因此应当考虑生长--气候因子之间的非线性关系以及物种和性别因素对生长--气候关系的影响,以期完善植株生长对气候的响应机制。 相似文献
97.
氮肥与密度互作对单粒精播花生根系形态、植株性状及产量的影响 总被引:1,自引:0,他引:1
Jun-Hua LIU Zheng-Feng WU Pu SHEN Tian-Yi YU Yong-Mei ZHENG Xue-Wu SUN Lin LI Dian-Xu CHEN Cai-Bin WANG Shu-Bo WAN 《作物学报》2020,46(10):1605-1616
为明确花生单粒精播适宜的氮肥水平和种植密度,本研究于2018年和2019年以‘花育22’为供试花生品种,设置3个氮肥水平(0 kg hm~(–2), N0; 60 kg hm~(–2), N1; 120 kg hm~(–2), N2), 3个种植密度(7.93万株hm~(–2), D1; 15.86万株hm~(–2),D2; 23.79万株hm~(–2), D3),采用二因素裂区试验设计,研究氮肥、密度及其互作对单粒精播花生根系形态、植株性状及产量的影响。氮肥对花生根长、根表面积、根体积、根干重的影响不显著,而密度的影响显著。单株根长、根表面积、根体积及根系干重随密度的增加而降低, D1显著高于D2和D3, D2、D3处理间差异不显著;单位面积根长、根表面积、根体积及根系干重随密度的增加而增加, D1显著低于D2和D3, D2、D3处理间差异不显著。氮肥和密度互作对2019年收获期单位面积根长、根表面积的影响显著,与D1相比, N1处理下D3的增幅显著高于N0和N2处理。氮肥及氮肥与密度互作对植株性状的影响存在年度和时期间的差异,主茎叶片数、侧枝数和主茎第一节间粗随密度增加有降低趋势。氮肥对荚果产量的影响不显著,荚果产量随密度的增加呈增加的趋势。产量与根体积、根干重、主茎叶片数、主茎高及侧枝长呈显著正相关。综上所述,在本试验条件下,花生单粒精播适宜的氮肥(N)水平为60 kg hm~(-2),种植密度为18.8万株hm~(-2)。 相似文献
98.
本研究从已构建的苦瓜果实均一化文库筛选得到一个EIN3-like同源EST序列,结合RACE技术,克隆得到EIN3基因c DNA全长序列,命名为Mc EIL2(Gen Bank登录号:KF595122)。该基因全长2 122 bp,开放阅读框1 890 bp,编码629个氨基酸,预测该蛋白的分子量为71.58 k D,与黄瓜Cus EIN3、甜瓜Cm EIL1、苜蓿Mt EIL1、绿豆Vr EIL1和番茄Le EIL1的蛋白同源性分别为89.61%、78.37%、71.23%、69.09%和65.66%。Mc EIL2基因的编码蛋白亚细胞定位于细胞核,荧光定量分析表明Mc EIL2基因表达量在幼果期先强后弱,绿熟期最低,破色期表达量大幅增加至最高随后下降,推测该基因参与苦瓜果实成熟软化调控过程。本研究初步明确了Mc EIL2基因在苦瓜成熟过程表达模式,可为今后进一步揭示苦瓜果实成熟软化的分子机制奠定基础。 相似文献
99.
Genetic divergence in two tropical maize composites after four cycles of reciprocal recurrent selection 下载免费PDF全文
Adesike O. Kolawole Abebe Menkir Melaku Gedil Essie Blay Kwadwo Ofori Jennifer G. Kling 《Plant Breeding》2017,136(1):41-49
Two tropical maize composites were subjected to four cycles of reciprocal recurrent selection to develop divergent inbred lines with good combining ability. This study was conducted to examine the extent of genetic diversity, changes in allele composition and genetic structure, of 100 randomly selected S1 lines each from the original (C0) and advanced (C4) selection cycles of TZL COMP3 and TZL COMP4, genotyped using single nucleotide polymorphism (SNP) markers. Results revealed that the proportion of alleles at both low and high frequencies decreased from C0 to C4, whereas those at intermediate frequencies increased at C4 in the two composites. More unique and other alleles were lost at C4 in TZL COMP3 relative to those in TZL COMP4. The changes in different measures of genetic diversity were either small or negligible with selection in the two composites. The proportion of markers departing from Hardy–Weinberg equilibrium (HWE) decreased with selection, whereas the total number of pairs of markers in linkage disequilibrium increased with selection in the two composites. Examination of changes in population structures using a model‐based approach as well as cluster and multivariate analyses found a high degree of concordance in stratifying the 400 S1 lines into four non‐overlapping groups corresponding to the two selection cycles each within the reciprocal composites. The observed molecular‐based divergence between cycles within the same composite and the clear differentiation between the complementary composites highlight the importance of reciprocal recurrent selection for preserving genetic diversity for long‐term selection. This increases the potential of the advanced selection cycles to sustain genetic gain in productivity of hybrids adapted to the savannas in West and Central Africa. 相似文献
100.
AIM: To explore the clinical significance of Krüpple-like factor 15 (KLF15) protein expression in the patients with lung adenocarcinoma for exploring the therapeutic and prognositic biomarkers of lung cancer. METHODS: Four cases of lung adenocarcinoma tissues and matched adjacent tissues were collected from our hospital, and the expression of KLF15 protein in these tissues was analyzed by Western blot. At the same time, 72 cases of archived paraffin-embedded samples and clinical data of the patients with lung adenocarcinoma were also collected. The KLF15 protein expression in the archived paraffin-embedded lung adenocarcinoma samples was detected by immunohistochemical staining. The correlations between KLF15 protein expression and clinical characteristics of the patients including prognosis were also analyzed. In addition, the KLF15 protein was up-regulated in A549 cells, and then the effects of KLF15 protein on the viability of the cells were measured by CCK-8 assay. RESULTS: The protein expression of KLF15 in the 4 cases of lung adenocarcinoma tissues was significantly lower than that in matched paracancerous tissues. Fifty-three cases of lung adenocarcinoma specimens showed low expression or no expression of KLF15 protein in total 72 cases (73.6%). The 5-year survival rate of the patients with high expression of KLF15 protein in their specimens was higher than that of the patients with the low expression of KLF15 protein (P<0.01), and the expression of KLF15 protein was significantly correlated with the pathological staging (P<0.01) and T stage (P<0.01) of the patients with lung adenocarcinoma. Furthermore, the low expression of KLF15 protein was an important poor prognostic indicator of the patients. Up-regulation of KLF15 protein in the A549 cells significantly inhibited the growth of the cells. CONCLUSION: KLF15 inhibits the growth of lung adenocarcinoma cells. It could be used as a therapeutic target and a prognostic biomarker for the patients with lung adenocarcinoma. 相似文献