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钱开胜 《柑桔与亚热带果树信息》2002,18(10):42-42
生产上，常遇到果农埋怨银杏树不开花挂果，有的甚至丧失信心，将栽培了10多年的银杏树砍伐换种其他果树。笔调查发现，银杏树栽种近10年后仍难以开花结果的原因，除肥水管理条件外，主要是种苗问题。前些年，因全国各地掀起种植银杏热，有些银杏果苗生产为了获取暴利，在培育嫁接苗时，取用了大量低产劣质植株或雄株上的枝条作接穗，有的甚至直接采用“本砧本穗”(即将砧木苗的上段枝条芽嫁接于下段)，有的则完全是实生砧木苗，仅在苗木基部用嫁接刀割划出一道伤口，冒充嫁接苗。生产中采用了这些种苗，自然难以实现早结果，对此果农曾采用切接和枝接方法高接换种，但成活率都很低。笔在桂东北一带指导果农生产时，发现采用秋季芽接对上述不结果银杏树效果显。 相似文献
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北方冬季保护地桃应用壁蜂授粉研究 总被引：2，自引：0，他引：2
北方冬季在日光温室中应用壁蜂为桃树授粉，壁蜂破草出巢始期和高峰期比露地推迟，整个破茧出巢期延长。保护地桃利用壁蜂授粉放蜂时间应在桃树开花前７－１０ｄ。日光温室内度达到１４．５℃成蜂开始出巢采粉和营巢，２２－２５℃活动频繁。 相似文献
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果树授粉昆虫—紫壁蜂,凹唇壁蜂生物学研究 总被引：16，自引：0，他引：16
紫壁蜂，凹唇壁蜂喜在人工巢管内营巢，在果园中用芦苇管和纸管设巢可回收大量蜂种。它们均为一年一代。卵，幼虫，蛹在巢管内生长发育，成虫羽化后以滞育状态在茧内越冬。早春用０－４℃冰箱冷藏蜂茧，待果树开花前１周左右在园内释放。两种壁蜂访花范围是杏，樱桃，李，桃，梨，苹果等。壁蜂访花采蜜繁衍后代，同时提高了花朵丛刊要率及果品质量，两种壁蜂访花速度快，工作时间长，授粉能力强，因此成为我国北方果树优良授粉昆虫。 相似文献
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以黄瓜为受体,研究了银杏、毛白杨、油松、杨树、法桐、泡桐6种行道树落叶提取物对黄瓜的化感作用。结果表明：6种行道树落叶提取物对黄瓜均具有化感作用,但化感作用性质、作用强度各不相同。6种行道树落叶提取物对黄瓜苗高表现为促进作用,而对发芽率和干质量无作用|银杏、毛白杨、油松对根长表现为促进作用,杨树为抑制作用,法桐无作用,泡桐则为促进/抑制双重作用|银杏、毛白杨对幼苗鲜质量表现为促进作用,其他叶片无作用。根据综合敏感指数,行道树落叶化感作用强度银杏＞毛白杨＞法桐＞油松＞泡桐＞杨树|黄瓜各性状敏感性苗高＞鲜质量＞根长＞干质量＞发芽率。 相似文献
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We examined responses of Siberian flying squirrels ( Pteromys volans ) to edges between nesting habitat (mature spruce forests), movement habitat (other forests, pine bogs), and open areas within their home ranges in southern Finland in 1996-2000. Radio-tracked squirrels (n=146) were generally associated to edges when they were ac tive at night. Compared to distances expected from the habitat pattern of their home range, squirrels occurred closer to high-contrast edges (of open areas) and low-contrast edges (nesting or movement forest types). Asso ciation with edges of open areas was more pronounced when squirrels were in movement habitat than in nesting habitat, possibly because of stronger channeling of movements in the former habitat. When in nesting habitat, squirrels responded more strongly to field edges than to recent clearcut edges, probably as a result of the pres ence of more deciduous trees on field edges, unlike clearcut edges. Responses to open areas were independent of spatial scale. However, responses to movement habitat from nesting habitat, and vice versa, were more pronounced over hundreds than tens of meters. Nesting cavities and dreys were generally located at random with respect to edges. We conclude that squirrel responses to edges of landscape attributes are diverse and depend both on spatial scale and edge contrast.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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叶籽银杏DNA甲基化水平与模式变异的研究 总被引：1，自引：0，他引：1
以萌动期与展叶期的叶籽银杏和银杏为试材,采用基于DNA甲基化敏感扩增多态性分析（Methylation-sensitive amplification polymorphism,MSAP）方法,在全基因组水平上探究叶籽银杏、银杏不同发育期DNA序列中CCGG位点的甲基化水平及模式变化特征。萌动期选用22对引物,在叶籽银杏和银杏中检测到扩增位点为498和384个,甲基化位点为237和165个,其总甲基化率分别为47.6%和42.4%;展叶期选用40对引物,在叶籽银杏有叶生胚珠（YZ2）、无叶生胚珠（YC）及银杏（CK）叶片中检测到扩增位点767、600及367个,甲基化位点分别为370、244及152个,其总甲基化率分别为48.3%、40.5%及41.5%。进一步对不同发育期叶籽银杏、银杏DNA甲基化模式的变化特征进行分析,结果显示：萌动期、展叶期叶籽银杏与银杏相比均有超过半数的位点（52.1%、54.6%及64.2%）DNA甲基化模式发生多态性变化,萌动期叶籽银杏相对于银杏其变化趋势以超甲基化为主;展叶期叶籽银杏有叶生胚珠相对于叶籽银杏无叶生胚珠及银杏甲基化的变化趋势以超甲基化为主,叶籽银杏有叶生胚珠相对于银杏DNA甲基化模式变异幅度更大,超甲基化水平更高,显示出叶籽银杏基因组独特的DNA甲基化特征。 相似文献
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利用AFLP技术,对来源于全国20个省(区)的180份银杏古树种质进行遗传多样性分析,在此基础上,利用逐步聚类的方法构建核心种质。结果表明,8对AFLP引物组合共扩增出1 646条谱带,多态条带百分率(PPB)为100%;平均观测等位基因数(Na)、平均有效等位基因数(Ne)、平均Nei’s基因多样度(H)和平均Shannon’s信息指数(I)分别为2.0000、1.2575、0.1662和0.2746;各种质间的遗传相似系数在0.6904~0.9115之间,平均值为0.7919。建立的银杏古树核心种质保留了原始种质的35%的样品。t检验结果表明,所构建的核心种质遗传多样性指数与原始种质差异不显著,能够最大程度的代表原始种质资源。 相似文献
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As an important part of urban greening, the canopy of street trees has ecological benefits, such as oxygen production, noise reduction, and dust reduction. The living vegetation volume (LVV) can reflect the spatial structure of the canopy intuitively and enables the estimation of the ecological service value of street trees. Terrestrial laser scanning (TLS) has shown excellent performance for providing three-dimensional data of individual trees with high precision, enabling the accurate quantification of the LVV. In this study, we divided the LVV into the total living vegetation volume (tLVV) and the effective living vegetation volume (eLVV); the latter does not include branches. The eLVV of 40 ginkgo trees separated in two roads in Nanjing was calculated from TLS data. A novel method named LAIM for accurate eLVV calculation based on point cloud data was proposed. The point cloud data of individual tree was segmented along the Z-axis and image processing methods were used. With this, eLVV of each tree was obtained. The results were compared with data obtained from a clustered point cloud generated using convex hulls. The Bland-Altman analysis was used to investigate the consistency of the two methods. Furthermore, we used correlation analysis and all-subsets regression to choose the variables, and the eLVV was fitted using six models. Finally, we evaluated O2 production, CO2 and SO2 absorption by the street trees based on eLVV, the ecological benefits of street trees were quantified. The results showed the following: (1) The number of layers and the dilation size of the point cloud were crucial parameters in the LAIM. (2) For ginkgo trees, the mean difference between the eLVV obtained from the LAIM and the convex hull method was − 0.53–0.19 m3, indicating that the results were highly consistent for the two methods. (3) The eLVV fitting performance was better for the exponential function model (R2 =0.8523, RMSE=0.6838 m3) and linear model (R2 =0.8361, RMSE=0.7224 m3). The tree height and crown width significantly affected the eLVV estimation. (4) The evaluation about ecological benefits of Zhaoyang Road was better than Cuizhu Road. The quantified ecological benefits were conducive to road ecological evaluation. This study quantified the eLVV of individual trees using TLS, highlighting the importance of live vegetation in urban greening. The results can provide technical support for estimating the ecological service value of urban street trees. 相似文献
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本文介绍了建瓯市银杏种植现状,并总结了银杏速生丰产栽培技术,包括栽植地选择、整地、挖穴与栽植、矮化拉枝、整形修剪、雌雄同株嫁接、水肥管理、病虫害防治等方面内容,对建瓯市银杏种植实现速生丰产有一定借鉴意义。 相似文献
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为降低食用菌生产成本,实现农林废弃物的资源化利用,利用板栗苞、银杏叶分别开展不同比例（5%、10%、15%）代替棉籽壳栽培效果试验,比较分析不同处理平菇、秀珍菇的菌丝生长、子实体性状、产量和生物转化效率。结果表明：与对照（棉籽壳87%、麦麸10%、石灰3%）相比较,配方板栗苞10%、棉籽壳78%、麦麸10%、石灰3%能促进平菇菌盖的生长,提升平菇品质,对平菇菌丝有一定的抑制作用;但可促进秀珍菇菌丝的生长;平菇、秀珍菇单袋产量分别为1 077.53、815.53 g,生物转化率分别比对照提高31.40、32.40个百分点。配方银杏叶10%、棉籽壳78%、麦麸10%、石灰3%能促进平菇、秀珍菇菌丝的生长,单袋产量分别为1 010.16、608.93 g,生物转化率分别比对照提高20.55、3.50个百分点。板栗苞、银杏叶可用于平菇、秀珍菇生产。 相似文献
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传统银杏产业结构复杂,但仍然以第一产业为主,各银杏产业区呈现出不同程度的产能结构性失衡。山东省郯城县银杏产业实施了以提质增效、创造品牌、优化"三产"融合为突破口的供给侧结构性改革,提出深度挖掘银杏产业多种功能、优化一二三产融合结构、培育发展"第六产业",打造特色银杏小镇、创建银杏产业集群等改革路径。 相似文献