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61.
62.
采用室内培养皿法,测试除虫菊地上部分水浸液对田间常见6种杂草种苗生长的影响。结果表明:不同质量浓度水浸液对杂草种苗生长的抑制作用依质量浓度梯度存在差异,除播娘蒿外其他5种总体均表现"低促高抑"趋势,在最高质量浓度0.03g·mL-1处理下,抑制作用最强;杂草种苗所受抑制作用大小依受体杂草种类存在差异,总体抑制作用由大到小依次为播娘蒿泽漆雀麦婆婆纳反枝苋野燕麦;除虫菊地上部分水浸液对试验杂草生理代谢影响测试表明,高质量浓度水浸液处理下,杂草幼苗受氧化胁迫严重。双子叶杂草较单子叶杂草对水浸液更敏感。 相似文献
63.
小麦茎秆实心度对茎秆强度的影响及相关性状QTL分析 总被引:1,自引:0,他引:1
在QTL水平上研究茎秆实心度与强度的遗传关系及实心度对茎秆强度的影响,为小麦抗倒伏育种提供依据。利用普通小麦宁麦18与实秆小麦种质"武云实秆"的F2群体和F2:3家系,对小麦茎秆强度、实心度及影响实心度的相关性状包括厚径比、壁厚、茎粗和髓腔直径进行了相关分析,并对茎秆强度相关性状QTL进行分子标记定位及遗传效应分析。结果表明小麦茎秆强度与厚径比、壁厚均呈极显著正相关,与髓腔直径呈极显著负相关。基于复合区间作图法进行QTL定位,检测到与茎秆强度、厚径比、壁厚、茎粗和髓腔直径相关QTL共23个,分布在1B、3B、4A、4B、5A上,表型贡献率3.5%~44.0%。在染色体3B、4A和5A上的标记区间gwm547–gwm247、wmc718–wmc468和gwm156–gwm443均检测到贡献率很高的茎秆实心度相关QTL,说明在这3条染色体上可能存在控制茎秆强度的主效QTL。用普通小麦宁麦13(N13)×武云实秆的24个F7家系检验分子标记gwm247的可靠性表明利用标记gwm247选育茎秆实心度优于宁麦13的概率较大。研究结果为进一步精细定位相关主效QTL以及分子标记辅助改良小麦茎秆强度奠定了基础。 相似文献
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65.
The purpose of this study was to identify the dominant pathogens of Curvularia leaf spot and their pathogenicity variation in Huanghuaihai Region of China in recent years. In 2013 and 2016–2017, the occurrences of Curvularia leaf spots on maize were investigated in fields located in Henan, Hebei, Shandong, and Anhui provinces, and 292 fungi were isolated from diseased leaves. These fungal isolates were subjected to morphological identification, and 232 isolates were found to have about 70% uncurved conidia and were identified as Curvularia lunata var. Most of the conidia of 2 representative isolates, namely, HNWB-131 and HNWB-185, were oblong with parallel septations and were distinctly different from a reference isolate CX-3. For further determination, the internal transcribed spacer(ITS), glyceraldehyde 3-phosphate dehydrogenase(GPDH), the large subunit(LSU), and translation elongation factor 1-alpha(EF1-α) sequences of HNWB-131, HNWB-185, and CX-3 were amplified and sequenced. The results of sequence analysis showed that the 4 gene sequences from the 3 isolates had a similarity of more than 99% to C. lunata. Based on the sequences of ITS and the combined data of the 4 genes, neighbor-joining trees were constructed for phylogenetic analysis. The results indicated that these 3 isolates were clustered together with C. lunata. The expression of Clg2 p and ClUrase genes in mycelia and conidia was significantly(P0.05) higher in CX-3 than in HNWB-131 and HNWB-185. This study found that the dominant pathogen of Curvularia leaf spot was a new variety of C. lunata with morphological variations in Huanghuaihai Region from 2013 to 2017. The pathogenicity of the C. lunata var. was not significantly enhanced, and the expression of Clg2 p and ClUrase genes of C. lunata var. was decreased. 相似文献
66.
67.
水稻育苗基质可持续利用研究现状及建议对策 总被引:2,自引:0,他引:2
水稻育苗基质的可持续利用不仅关乎水稻生产,同时直接关系农业经济发展。辽宁作为北方粳稻主要产区,在当前大力发展水稻工厂化育苗的条件下,开展新型育苗基质的研发、示范与推广,是解决当前水稻育苗可持续利用的有效途径,也是今后水稻生产的发展趋势, 相似文献
68.
为了充分利用农业废弃物小麦秸秆,进行草炭替代性育苗基质原料的研发,实现农业资源循环化利用和生态可持续发展。以番茄‘毛粉802’为材料,通过小麦秸秆腐熟物、草炭、蛭石和珍珠岩4种基质原料及1种生物菌肥进行不同体积配比处理,研究不同配比的小麦秸秆复合基质对番茄幼苗生长指标、叶片色素及荧光指标、幼苗叶片理化性质指标、基质生物指标和理化性质的影响,探究适合番茄幼苗生长的小麦秸秆复合育苗基质配方。利用灰色关联法对19项指标进行综合分析。结果表明,V腐熟小麦秸秆∶V蛭石∶V珍珠岩∶V生物菌肥=6∶2.5∶1∶0.5番茄幼苗表现最好,而番茄幼苗在纯小麦秸秆腐熟物上的生长量远远低于其他处理,番茄幼苗的表现最差。 相似文献
69.
长链酯酰辅酶A合成酶(ACSLs)是长链脂肪酸通过硫代酯化进而合成酰基辅酶A衍生物所必需的酶,也是脂肪酸代谢的第一步。哺乳动物ACSL家族由ACSL1、ACSL3、ACSL4、ACSL5和ACSL65个不同的成员组成,ACSL1是主要的异构体之一。为探讨黄羽肉鸡ACSL1基因作为腹脂性状分子标记的可行性,本实验采用PCR-直接测序技术对黄羽肉鸡ACSL1基因进行遗传多态性分析。结果显示:黄羽肉鸡ACSL1基因第17到第18外显子区域(1295 bp)SNPs位点较丰富,T32126C、C32013T、A31958G这3个位点的等位基因频率符合哈代-温伯格平衡,且A31958G突变位点、T32126C突变位点与腹脂重、腹脂率不相关,C32013T突变位点对鸡的腹脂重与腹脂率有显著影响,提示能够利用C32013T突变位点对黄羽肉鸡腹脂重进行分子标记辅助选择。 相似文献
70.
In cucumber, the genetic basis of traits under domestication and/or diversifying selection is not well understood. Here, we reported QTL mapping for flowering time and fruit size-related traits with segregating populations derived from a cultivated × wild cross. Phenotypic data of flowering time (FT), fruit size (FS), fruit number (FN) and fruit weight per plant (FW) were collected in multiple environments. QTL analysis identified 19 QTL for these traits. We found that the major-effect QTL FT1.1 played an important role in regulating flowering time in cultivated cucumber, whereas the minor-effect QTL FT6.3 contributed to photoperiod sensitive flowering time during domestication. Two novel consensus FS QTL, FS1.4 and FS2.3, seem to be the targets of selection during breeding for the US processing cucumber. All other FS QTL were co-localized with previously detected QTL using populations derived from cultivated cucumbers, suggesting that they were under selection during both initial domestication and subsequent improvement. Results from this study also suggested that the wild cucumber is a useful resource for capturing positive transgressive segregation and novel alleles that could be explored in cucumber breeding. 相似文献