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运用8种聚集度指标对山楂叶螨卵在桃树上的空间分布型进行了研究,所有的指标都表明,山楂叶螨卵的空间分布型呈聚集分布,分布的基本成份是个体群,通过方差分析,山楂叶螨卵在桃树树冠的上、中、下3个层的分布数量差异都不显著。 相似文献
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１５ａ的研究结果表明：在冀中南部果产区,山楂叶螨种群消长呈单峰曲线,不同年份或同一年份不同果园的发生高峰不同,梨、桃园发生在６月下旬至７月中旬,苹果园发生在６月中旬至８月上旬。发生高峰的温湿度界限指标是旬日均温度２６．１４±２．１１℃,日均相对湿度６１．６７％±８．９２％;在发育起点温度（９．２℃）与界限指标温度范围内,种群增长与有效积温呈高度正相关,符合线性函数ｌｏｇｙ＝－３．５５７４＋２．５１９５ｌｏｇｘ,在果园和树冠内的种群空间分布属聚集型;山楂叶螨危害苹果、梨、桃树造成早期落叶的螨口指标分别是叶均３１．７９、３２．３４、１９．４７头（均指雌成螨）,叶片被害指数分别为６１．２７％、６０．０７％和５８．０１％。 相似文献
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苏氏盲走螨对山楂叶螨卵和幼螨的功能反应均可用Ｈｏｌｌｉｎｇ的圆盘方程模拟。在室内自然变温条件下,苏氏盲走螨对山楂叶螨卵和幼螨的最大日捕食量分别为６２．５４粒和３．８８头,时攻击率分别为０．２８０６和０．５５４４;在山楂叶螨各螨态中,对卵有明显的正喜好,其次是幼螨。 相似文献
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采用扩散系数C、Lloyd的指标L、Iwao回归及Taylor幂的法则测定:针叶小爪螨越冬卵孵化盛期活动螨在叶片上存在着个体群,个体群的空间分布为聚集分布,且具聚集度的密度依赖性。在此基础上,给出了理论抽样数和序贯抽样方案。并对活动螨的聚集原因作了探讨。 相似文献
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一、二斑叶螨的危害。二斑叶螨主要为害桃树，对梨树，葡萄，杏，山楂等危害也比较严重。二斑叶螨以若螨，成螨聚集在果树叶片的背面刺吸汁液，危害轻时，受害叶片失绿，呈浅白色；危害严重时，叶片焦枯脱落；虫口密度大时，在叶片背面结一层白色丝网或在新梢顶端群虫集结呈球状。 相似文献
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红蜘蛛种类较多,主要有山楂红蜘蛛、苹果红蜘蛛、苹果白蜘蛛、苜蓿红蜘蛛等。危害桃树的红蜘蛛主要是山楂红蜘蛛。山楂红蜘蛛又称山楂叶螨。1年发 相似文献
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桃树蚜虫越冬卵空间分布规律 总被引：1，自引：0，他引：1
2006年以来．在桃树害虫综合治理的实践中发现,桃树蚜虫越冬卵分布很不均匀。为此,从桃树蚜虫越冬卵的分布入手进行了认真细致的调查,把桃树赤蚜、桃粉蚜、桃瘤蚜3种越冬卵作为1个混合体进行研究。并运用生物数学的方法进行运标统计,得出桃蚜越冬卵呈聚集型分布。为桃树蚜虫的测报和防治提供了科学的依据。 相似文献
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一、二斑叶螨的危害二斑叶螨主要为害桃树,对梨树、葡萄、杏、山楂等危害也比较严重。二斑叶螨以若螨、成螨聚集在果树叶片的背面刺吸汁液,危害轻时,受害叶片失绿,呈浅白色;危害严重时,叶片焦枯脱落;虫口密度大时,在叶片背面结一层白色丝网或在新梢顶端群虫集结呈球状。二、二斑叶螨的发生规律二斑叶螨以受精成螨在果树根颈部,树翘皮裂缝处,落叶和地下杂草上越冬。翌年3月下旬,地下越冬的雌成螨先出蛰,集中在宿根性杂草如荠菜、苦菜等上生活出蛰,盛期在3月上旬,3月下旬陆续上树危害。树上越冬的雌成螨3月上旬出蛰,盛期在3月中旬,3月下旬出蛰… 相似文献
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扫螨净，尼索朗、三氯杀螨醇３种杀螨剂对山楂叶螨的防治试验表明：扫螨净３０００倍液对山楂叶螨的卵、幼若螨、成螨均有极强的触杀效果，其田间有效期长达５０天，一次用药可基本控制全年危害，效果优于尼索朗、三氯杀螨醇。 相似文献
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大棚内栽培桃树与露地果园生长的桃树病虫害种类与发生特点有所不同,通过对大棚栽培桃树病虫害调查,查明主要病虫害的种类与发生特点,为防治工作提供依据。结果表明,大棚桃树主要病虫害种类共有20种,其中病害6种,虫害14种,主要的必须进行防治的病虫害有桃细菌性穿孔病、桃流胶病、桃根癌病、桃蚜、桃粉大尾蚜、山楂红蜘蛛、桃潜蛾、小绿叶蝉8种。通过对主要病虫害的发生危害规律的观察,总结出发生特点。 相似文献
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根据根癌土壤杆菌Ti质粒的保守序列设计了2对引物,对我国不同木本植物上分离鉴定的10株致病性根癌土壤杆菌进行PCR,致瘤性根癌土壤杆菌(Agrobacterium tumefaciens)扩增出427 bp和338 bp的特异性DNA片段,而发根土壤杆菌(A.rhizogenes)仅扩增出338 bp片段,放线土壤杆菌(A.radiobacter)、丁香假单胞菌(Pseudomonas syringae)和泡桐丛枝病植原体(phytoplasma)皆未有特异扩增带.用CYT/CYT'引物对也可鉴定T-DNA遗传转化瘤组织,而VirD2A/VirD2E可用于工程土壤杆菌株侵染能力鉴定.从北京通州杨树苗圃和河北廊坊桃园的病树冠瘿组织和土壤中经选择培养基分离菌株,然后PCR筛选出6个致病性根癌土壤杆菌菌株,而未能从施用过抗根癌生防制剂的北京玉渊潭公园樱花根癌病园中分离和鉴定出典型的致病根癌土壤杆菌株.将杨树根癌土壤杆菌菌株(CFCC1001)异戊烯基转移酶基因(ipt)片段克隆和序列测定结果显示与A.tumefaciens Ti15955菌株的ipt基因序列同源性为83.64%.用此片段制备的ipt cRNA基因探针进行斑点杂交和Northern blot,结果显示此探针与杨树根癌土壤杆菌以及玫瑰、樱花、海棠、桃树等木本植物上分离鉴定的致病土壤杆菌菌株所扩增出的427 bp片段都有明显杂交信号,但与引起泡桐丛枝病植原体染色质和染色质外DNA均未有明显杂交信号. 相似文献
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笔者在广泛调研的基础上,筛选出了适宜在晋北发展和推广的山桃、西伯利亚杏、毛樱桃、刺梨4种经济林灌木,测定其树冠截持降水量、林地枯落物水容量、林地土壤养分、根系分布。结果认为：4种灌木能有效截持降水,减少地表径流;枯落物水容量大、营养丰富,可改良土壤,增加土壤肥力;灌木根系发达,可提高土壤抗蚀能力。同时分析了灌木资源的经济价值,为大面积开发利用灌木资源提供了依据。 相似文献
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Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive wood-boring beetle first detected in North America in 2002. Relatively little is known about the factors affecting the mating and oviposition behavior of EAB, even though they could have implications for the management of this species. Consequently, we conducted field surveys in Michigan to observe the diurnal behavior of EAB adults, in addition to examining how their behaviors associated with reproduction varied in relation to the size and condition of host trees. We observed most EAB adults between 11:00 and 15:00, and this pattern was the same for both sexes and for all of the specific behaviors examined (feeding, flying, mating, resting, and walking). Regarding host tree size and crown condition, we consistently found that the most EAB eggs, adults, mating pairs, and ovipositing females were observed on intermediately stressed trees with 40–60 % crown reductions (likely resulting from earlier EAB infestations). Additionally, host tree crown condition appeared to be a more important factor than diameter at breast height. Our results therefore provide support to the hypothesis that host tree crown (stressing) condition influences EAB oviposition behavior. Determining which trees are likely to contain the most EAB eggs should help to guide efforts for releasing and promoting the establishment of parasitoids utilized in biologic control. However, future work should attempt to experimentally test the hypothesis that host tree condition (e.g., crown reduction) drives EAB oviposition behavior, and investigate the fitness implications of these host choices. 相似文献
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Photosynthetic light acclimation of leaves can result from (i) changes in mass-based leaf nitrogen concentration, Nm, (ii) changes in leaf mass:area ratio, Ma, and (iii) partitioning of total leaf nitrogen among different pools of the photosynthetic machinery. We studied variations in Nm and Ma within the crowns of two peach (Prunus persica L. Batsch) trees grown in an orchard in Portugal, and one peach tree grown in an orchard in France. Each crown was digitized and a 3-D radiation transfer model was used to quantify the intra-crown variations in time-integrated leaf irradiance, . Nitrogen concentration, leaf mass:area ratio, chlorophyll concentration, and photosynthetic capacity were also measured on leaves sampled on five additional peach trees in the orchard in Portugal. The data were used to compute the coefficients of leaf nitrogen partitioning among carboxylation, bioenergetics, and light harvesting pools. Leaf mass:area ratio and area-based leaf nitrogen concentration, Na, were nonlinearly related to , and photosynthetic capacity was linearly related to Na. Photosynthetic light acclimation resulted mainly from changes in Ma and leaf nitrogen partitioning, and to a lesser extent from changes in Nm. This behavior contrasts with photosynthetic light acclimation observed in other tree species like walnut (Juglans regia L.) in which acclimation results primarily from changes in Ma. 相似文献
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蜀柏毒蛾卵与初龄幼虫种群空间格局的研究 总被引：1，自引：0，他引：1
根据m—m、m—s~2、logs~2—logm的相关分析,认为蜀柏毒蛾两代卵和初龄幼虫种群在林间呈负二项分布。其格局的结构均是以个体群结构存在,个体群内个体间相互吸引,第1代卵和两代的初龄幼虫个体群呈聚集分布,而越冬代卵期种群的个体群呈随机分布。探讨了公共K值,分析了聚集因素。 相似文献
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