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61.
辣椒植株水浸液对辣椒和番茄种子萌发的自毒作用 总被引:9,自引:0,他引:9
采用室内生物测定的方法,研究了辣椒全株、根、茎、叶水浸液的化感效应.结果表明,辣椒全株、根、茎、叶水浸液对辣椒和番茄种子萌发的影响依供体部位、水浸液浓度和受体不同而有差异,辣椒植株水浸液对辣椒和番茄种子发芽存在自毒作用.辣椒植株全株、根、茎、叶水浸提液对辣椒和番茄种子发芽表现为抑制作用,并随着浓度的增大,抑制作用增强,这表明辣椒植株水浸液对辣椒和番茄种子发芽有较强的自毒作用.综合而言,辣椒全株、根、茎、叶水浸液对辣椒的自毒作用强弱依次为叶>根>茎>全株,对番茄的自毒作用强弱依次为叶>全株>根>茎.显示辣椒叶水浸液的自毒作用最强. 相似文献
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为揭示环境因子对果园表层土壤氯离子迁移累积的影响,为预防和改良土壤次生盐渍化提供理论指导和相关依据,研究果树生育期表层土壤不同土层氯离子的变化与环境因子(土温、土壤水分、蒸发量、降雨量、水分亏值、气温、空气相对湿度)的相互关系。结果表明:在土壤0~25cm土层的微域范围内,不同土层对氯离子的迁移与累积具有不同的功能。0~5cm土层为氯离子聚集层,10~15cm土层为氯离子传导层。认为10~15cm土层是半干旱地区环境因子对土壤性质直接作用与影响的临界深度。 相似文献
67.
Pollinator assemblages may shift as a consequence of the destruction and fragmentation of natural habitats. The scarcity of mates and pollinators can lead plant populations to suffer from pollen limitation and a decrease in reproductive performance within fragmented areas. We studied the shift in pollinator assemblages along with pollen limitation and seed production patterns in the Mediterranean shrub Myrtus communis. Our study included six populations contrasting in patch and population size (Large vs. Small) within a fragmented landscape characterized by ∼1% of potential forest coverage. The breeding system in Myrtus communis was self-compatible, but compared with natural pollination, fruit set increased with pollen addition (quantity limited), and seed set (brood size) increased with outcross pollen addition (quality limited). While the pollinator assemblage in Large patches was taxonomically diverse, it was almost monopolized by honeybees in Small patches, where visitation rates were highest and wild bee species were almost absent. In general, Small populations were less pollen limited for fruit set than Large populations, particularly those that received the highest rates of honeybee visits. However, despite differences in fragmentation and pollinators between Large and Small populations, seed production patterns (brood size and seed mass) were rather similar among them, in agreement with similar pollen limitation levels found for brood size. A higher susceptibility of native pollinators to the presence of honeybee hives was found in Small patches, suggesting that the pollinator assemblage may be severely altered when fragmentation occurs in combination with beekeeping. We discuss its implications and effects on plant reproduction in fragmented areas. 相似文献
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TANG Jiu-you JIANG Ling ZHANG Wen-Wei WANG Chun-ming LIU Shi-jia CHEN Liang-Ming ZHAI Hu-qu Atsushi Yoshimura WAN Jian-min 《中国农业科学(英文版)》2004,3(9)
Quantitative trait loci(QTL)controlling seed dormancy in rice were identified using recombinant inbred lines(RILs)population derived from the cross between a japonica variety Kinmaze and an indica variety DV85. Seeds of two parental cultivars and each RIL were harvested in 35d after heading.. The germination percentage of these seeds at 30℃for 7 days were measured as the degree of seed dormancy.. QTL analysis was performed with Windows QTL Cartographer 1.13a program by composite interval mapping.. A total of four QTL for seed dormancy were detected on chromosome 2(two regions),5 and 11,respectively.Phenotypic variation explained by each QTL ranged from 8.37 to 17.40%.. Responses of such loci to a dormancy-breaking treatment with dry heat were further detected. The results showed that two alleles of qDOR-2-1 and qDOR-5 from DV85 as well as the allele of qDOR11 from Kinmaze increased the seed dormancy,which seemed to be easily broken by dry heat treatment. Such loci of seed dormancy may be applied to rice genetic improvement.The allele of qDOR-2-2 from DV85 increased the seed dormancy,which could not be broken by dry heat treatment. 相似文献
69.
高压静电场在香葱种子分选上的应用初探 总被引:1,自引:0,他引:1
香葱种子落入高压静电场中 ,受场强的作用 ,沿电场方向产生位移 ,根据种子粒重不同 ,分布的区域也不同 ,位移距离较小的种子粒重较大 ,种子活力高 ,电导率低。随着分布区间不同 ,种子活力呈现有规律的变化。因此 ,利用高压静电场选种可作为香葱种子分选的一种有效途径。 相似文献
70.
对赣南杉木一代种子园子代测定林37个家系3个对照进行4a生长性状进行调查,并进行指标比较、相关性和聚类分析。结果表明:(1)参试家系的树高和胸径生长量均达到极显著差异,树高指标的变异系数范围为0.0497~0.2583,遗传力范围为0.7417~0.9503,胸径指标的变异系数范围为0.1061~0.3491,遗传力范围为0.6509~0.8939;(2)树高和胸径两个变量间存在极显著的线性正相关关系,即胸径随着树高的增加而增加;(3)对37个参试家系和3个对照的树高和胸径指标进行聚类,将参试材料分为3类,最优类群为类群Ⅲ,以树高和胸径指标均大于类群均值,初选出类群Ⅲ的优良家系为47、57、59、100、176号等5个家系。 相似文献