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891.
采用OPAL HA202和“保得”对菜心进行浸种处理,可以促进菜心地上部分生长,增加干物质的积累,提早抽薹,有明显的增产作用,其中以OPAL HA202 200倍液处理增产效果最为显著。  相似文献   
892.
露水河林业局森林景观空间自相关分析与拟合   总被引:1,自引:1,他引:1  
空间自相关是建立森林景观模型中不可回避的问题,然而目前众多研究中常忽略了这一点,为了探解决考虑空间自相关性,建立森林景观模型的问题,以露水河林业局为例,采用空间自相关分析、半方差分析等手段分析红松森林景观等景观类型的空间自相关性。研究结果发现,Moran’s I指数以及半方差图显示红松在空间分布上具有较强的空间自相关性,但这种空间自相关性从1987-2003年呈现减弱趋势,红松的分布由非随机因素占主导地位逐渐变为随机因素占主导地位,采伐等人为因素对于红松的分布产生了重要影响。在此基础上分别利用经典线性回归模型和空间滞后模型建立了红松森林景观分布与环境驱动因子的模拟模型,经过比较,认为空间滞后模型的拟合度优于经典线性回归模型。  相似文献   
893.
为了制备抗猫杯状病毒的单克隆抗体,并对其基本生物学特性进行鉴定。分别采用饱和硫酸铵方法、差速离心、氯化铯密度梯度离心方法对猫杯状病毒(FCV)进行纯化,将纯化的猫杯状病毒作为抗原对BALB/c小鼠进行免疫,通过细胞融合和杂交瘤筛选技术建立抗猫杯状病毒单克隆抗体的杂交瘤系,鉴定单克隆抗体的亚型。结果表明:本实验获得了2株稳定分泌特异性抗猫杯状病毒单克隆抗体的杂交瘤细胞,分别命名为D8、E5,其亚型均为IgM。获得的单克隆抗体与犬细小病毒(CPV)、猫细小病毒(FPV)、犬瘟热病毒(CDV)均无交叉反应。成功制备了抗猫杯状病毒单克隆抗体,为建立相关诊断方法奠定了基础。  相似文献   
894.
水稻新品种DUS测试目测性状标准品种的优化筛选   总被引:2,自引:2,他引:2  
为了筛选出稳定可靠的水稻新品种DUS测试目测性状的标准品种,通过对中日韩117个有代表性的水稻已知品种2008-2009年连续2年的田间测试试验,对水稻DUS测试指南中的27个目测性状的106个性状表达状态进行了系统的标准品种筛选。结果表明,筛选出的16个标准品种不仅涵盖了原有的23个标准品种代表的性状,还为多个没有标准品种的性状表达状态提供了标准品种;‘元子占稻’、‘坦紫’、‘旱轮稻’、‘起金’、‘乌嘴糯’这5个品种具有较强的生态适应性,可作为其他生态区标准品种筛选时优先考虑的品种;聚类分析法在水稻目测性状标准品种筛选过程中具有重要作用,可作为其他植物新品种DUS测试目测性状标准品种筛选提供参考。  相似文献   
895.
低磷胁迫对不同基因型小麦品种苗期性状的影响   总被引:7,自引:0,他引:7  
为研究低磷胁迫对小麦苗期性状的影响,在对照(200 μmol/L KH2PO4)和低磷(5 μmol/L KH2PO4)条件下比较了6个不同基因型小麦品种苗期性状指标。结果表明,小麦根系和地上部对低磷胁迫的反应不同,低磷诱导小麦根系伸长,根系生物量(根鲜重和根干重)增加,供试的6个小麦品种在低磷条件下的根系鲜重和干重与对照相比差异均达到显著或极显著水平。低磷处理对地上部则表现出抑制作用,但对不同品种的影响程度差异较大。总体来看,低磷胁迫处理对小麦根系性状的影响大于地上部性状,不同苗期性状受低磷胁迫影响的程度分别为:根系鲜重>最长根长>根系干重>地上部鲜重>地上部干重>苗长。6个供试小麦品种中,‘中国春’对低磷胁迫最为敏感,而‘京411’的耐低磷性相对较强。  相似文献   
896.
Pea would benefit from the plasticity and adaptability of its cross-incompatible relatives Pisum fulvum and Lathyrus sativus L., and we have tested reciprocal sexual crossings by manually cross-pollinating plants of genotypes of these three species. Studies of in situ germination of pollen grains on stigmata showed that pollen tubes were generally unable to germinate or could not reach the ovary. A few putative hybrid pods were nevertheless harvested, with one grain per pod germinated in vitro, then micropropagated for flow cytometry, isoenzyme, molecular (ribosomal ITS PCR-RFLP) and genomic in situ hybridization (GISH) studies. One such grain was recovered from an inter-generic cross of P. sativum x L. sativus and four from an inter-specific P. sativum x P. fulvumcross. A strong cross-incompatibility was shown between pea and grass pea, where the putative hybrid turned out to be pea. Conversely, with the interspecific, P. sativum x P. fulvum cross, flow cytometry and isoenzymes with leaf tissues strongly suggested hybridity, while molecular approaches and GISH confirmed the production of inter-specific hybrids, and without the need for a wild type P. sativum accession as a bridging cross.  相似文献   
897.
Chromosome duplication—autopolyploidization—may affect plant morphology and breeding systems, ultimately enabling the production of improved genotypes. In this study, the autotetraploid lines obtained from the self-incompatible diploid Hylocereus monacanthus and the autooctapolyploid lines obtained from the self-compatible tetraploid H. megalanthus were studied and compared with the donor accessions. The resulting H. monacanthus autotetraploids exhibit lower fruit weight, seed number, and pollen viability than the donor plant, but it has larger pollen grains. Although the resulting H. megalanthus autooctaploids had larger pollen grains and lower pollen viability compared with the donor plant, only aborted fruits were obtained from these lines. The most valuable change observed was the breakdown of the self-incompatibility system in the H. monacanthus autotetraploid lines. This research provides important information on the horticultural value of vine cacti autopolyploid lines.  相似文献   
898.
Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety mixtures relative to their component varieties. For this purpose, six variety mixtures of spring barley and 14 component varieties were grown in each of 17 trial environments. A total of 28 observed and a priori plant characteristics, including grain yield, disease severity and weed competitiveness, were derived for each component variety in each trial. The relationship between inter-varietal diversity of each characteristic and the mixing effect on grain yield was analysed. Additionally, various types of yield stability were estimated and compared among mixtures and component varieties. One mixture out-yielded all of its component varieties in almost half of the trial environments. Inter-varietal diversity in grain yield potential correlated significantly with mixing effect, as did straw length diversity when weighted with weed pressure. The grain yields of most mixtures were more stable across environments than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity.  相似文献   
899.
Field experiments were conducted to evaluate the effects of eco-friendly organic matrix entrapped urea (OMEU) on growth, productivity, and yield of rice (Oryza sativa L. cv. Basmati) and soil enrichment in the paddy field at Rohtak (Haryana) located near Delhi. The OMEU prepared in granular form contained cow dung, rice bran (grain cover of Oryza sativa), powder of neem leaves (Azadirachta indica), and clay soil (diameter of particles < 0.02 mm) in 1:1:1:1 ratios and saresh (plant gum of Acacia sp.) as binder along with half of the recommended dose of commercially available soluble urea (free urea; FU). Single basal application of OMEU showed an increase in plant growth in terms of fresh and dry weights, root length, root, leaf and tiller numbers, soluble protein, total N and ammonium in leaves, productivity in terms of grain and straw yield, and nutritional and microbial activities of field soil over free form of urea and no fertilizer application. Nutritional status of rice grains was also improved over the free urea and no fertilizer controls. Our data indicate that OMEU, which is low cost and based on bio-degradable, non-toxic, and locally available agro-waste, can be attempted to replace the conventional use of soluble urea in rice.  相似文献   
900.
Variation patterns and inheritance of anthocyanin content in the ripe berries of a tetraploid × diploid table grape cross population were investigated in two successive years. The population segregated for three different ploid levels: dipolids, triploids, and tetraploids. A total of 28 different anthocyanins were detected and quantified in the progeny population. Transgressive segregation for the total anthocyanin content was observed in all the three ploid progeny populations. The total anthocyanin content increased as the ploid level increased. The broad sense heritabilities (H2) of the total anthocyanin content were all relatively high, ranging from 0.53 to 0.98, 0.57 to 0.97 and 0.43 to 0.94 in the diploid, triploid and tetraploid population, respectively. Our results suggested that the total anthocyanin content followed an additive inheritance model in this polyploid segregation population. We also observed that the relative contribution of individual anthocyanins to the total anthocyanin content varied significantly among different ploid populations, suggesting that genetic background has important impact on the accumulation of the individual anthocyanin compounds. These results will help develop better breeding strategies in a polyploid table grape breeding program for improving the content of anthocyanins, an important class of polyphenolics possessing antioxidant activities and many other health-related benefits.  相似文献   
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