共查询到19条相似文献,搜索用时 156 毫秒
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在苹果蠹蛾(Cydia pomonella L.)和梨小食心虫[Grapholita molesta(Busck)]混合发生的梨园,应用苹果蠹蛾性诱剂、梨小食心虫性诱剂监测和防治两种害虫。试验设置3组诱捕器,分别为苹果蠹蛾性诱剂诱芯单独放置、梨小食心虫性诱剂诱芯单独放置、以及同一诱捕器同时放置苹果蠹蛾和梨小食心虫性诱剂诱芯,比较不同诱捕器处理诱蛾效果差异。试验结果表明,试验梨园没有诱捕到苹果蠹蛾成虫,即没有苹果蠹蛾发生;但苹果蠹蛾性诱剂能显著提高梨小食心虫性诱剂的诱虫能力。本研究表明苹果蠹蛾性诱剂对梨小食心虫性诱剂诱虫效果具有显著的增效作用,在田间应用可以更好的监测和控制梨小食心虫的发生。 相似文献
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梨小食心虫(Grapholitha molesta Busck)是梨、桃、李等经济果树的重要害虫之一。为切实明确果实套袋方法在防控梨小食心虫上的应用,研究比较了不同时间、不同程度的和不同部位梨果套袋处理对梨小食心虫危害程度的影响。结果表明,套袋程度和套袋时间可显著影响梨小食心虫蛀果率及虫口数量,套袋时间越早、套袋程度越高,效果较好,梨树落花后20—40天后进行100%套袋,蛀果减退率96.96%,虫口减退率达90.51%;10%、30%套袋效果与不进行套袋无显著性差异;仅套取上部果实较仅套取中部果实和仅套取下部梨果,对梨小食心虫防控效果较好。 相似文献
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<正> 梨小食心虫,成虫危害规律受湿度影响较大,其危害时间长,面积也越来越大。如何及时、准确防治?我们自1985年起,在冀县南榆林果园应用梨小食心虫诱芯,测报田间蛾的发生高峰期。实践证明:含梨小性外激素的诱芯诱蛾 相似文献
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In 1992–2002, the flight activity of Adoxophyes orana (AO) was investigated using pheromone traps placed in apple orchards in five localities in Central and Eastern Bohemia. The
cumulative catches of AO were plotted against time expressed as the sum of day-degrees (D°) above 8°C and approximated by
a Richards’ function. This model was constructed using the numbers of AO males caught by pheromone traps from 1992–1998 at
all the localities. The flight of the overwintering generation of AO began when 200 D° had accumulated, culminated at 300
D° and ceased at 430 D°, irrespective of locality. The high predictive ability of the model was validated using data from
one locality for 2001–2003. It was impossible to construct a similar model to predict the flight activity of the summer generation
because its dependence on D° varied greatly between localities and years. 相似文献
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【目的】明确不同湿度条件下富士系苹果花过冷却点的分布频率,为苹果霜冻监测和预测提供参考。【方法】以中国种植最广泛的富士系苹果为研究对象,使用人工霜冻试验箱控制温湿度,模拟霜冻降温过程,设置高、中、低3个湿度范围,对富士系苹果花蕾和花朵子房过冷却点进行监测,研究环境相对湿度对富士系苹果花器官过冷却点的影响。【结果】富士系苹果花蕾和花朵子房过冷却点在-6.4^-1.9 ℃,50%的过冷却点集中在-4.4^-3.5 ℃,80%的过冷却点集中在-4.4^-2.5 ℃,平均过冷却点为-3.7 ℃。苹果花蕾和花朵子房的累积冻害率达到30%(轻度)的温度为-3.2 ℃,累积冻害率达到50%(中度)的温度为-3.6 ℃,累积冻害率达到80%(重度)的温度为-4.2 ℃。花蕾过冷却点的变异大于花朵子房过冷却点,不同湿度处理下花蕾和花朵子房过冷却点差异显著。中湿(相对湿度50%~70%)条件下,过冷却点最高,抗寒性最差,而低湿(相对湿度50%以下)和高湿(相对湿度大于70%)处理均可降低植株的过冷却点。【结论】-4.4^-2.5 ℃是富士系苹果花组织开始出现损伤的主要温度范围。干燥和高湿的环境均可降低富士系苹果花蕾和花朵的过冷却点,尤其是干燥的环境可降低苹果花蕾的过冷却点0.6 ℃,可降低苹果花朵子房的过冷却点0.4 ℃,提高苹果花蕾及花朵子房抗寒性。 相似文献
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Typhlodromus pyri Scheuten (Acari, Phytoseiidae) has been reported as the most important predator of the European red mite, Panonychus ulmi (Koch) (Acari, Tetranychidae) in apple culture. However, biological data on T. pyri was insufficient on important parameters like seasonal population dynamics and within-tree and on-leaf distribution in apple orchards in the region of Meckenheim, Germany. The purpose of the present work was, therefore, to obtain experimental data on these parameters of T. pyri from 2000 to 2002 in the apple orchards in this region. The results showed that overwintered females of T. pyri reactivate and start laying eggs between late March and early April. The mean daily number of the different stages of T. pyri per leaf peaked in July each year, where it ranged between 0.92–1.68 eggs, 0.81–1.41 nymphs, 0.64–1.32 females and 0.37–0.52 males. A significantly higher number of T. pyri individuals congregated in the bottom layer of trees (0.34–0.64 individuals/leaf) than in the middle and top layers (0.23–0.38 and 0.12–0.23 individuals/leaf, respectively). We found that 91.4–94.1% of the total eggs, 89.6–91.7% larvae, 73.0–76.5% nymphs, 60.5–64.6% adult females and 52.6–55.9% adult males concentrated their activities in the inner area of the leaf surface. More than 50% of the predatory mites congregated in the bottom layer in winter. Mean total density of the overwintering females in December of 2000,2001 and 2002 ranged between 10.6–14.2 females/5 cm twig in the bottom, 7.3–10.4 in the middle and 4.1–6.9 in the top layers of the apple trees. Mean total fecundity recorded over the 3 years was lowest in the overwintering generation with 31.8–37.6 eggs/female, highest in the June generation with 45.9–53.7 eggs/female, and intermediate in the August generation with 41.5–46.1 eggs/female. The overwintering generation was composed entirely of females, while the female to male ratio in the June generation was 2:1, and in the August generation 3:1. T. pyri overwinters as adult females in rough structures, cracks and crevices of twigs. 相似文献
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琯溪蜜柚园土壤酸化特征研究 总被引:5,自引:0,他引:5
【目的】为了研究蜜柚园土壤的酸化特征,从而为蜜柚园土壤改良提供参考依据。【方法】采集福建省平和县319个蜜柚园的土壤样品和25个蜜柚园土壤剖面表土层(0~20 cm)、亚表土层(20~40 cm)和底土层(40~60 cm)的土壤样品,分析了蜜柚园土壤pH值的分布特征、影响蜜柚园土壤酸化的因素和土壤pH值与盐基饱和度和交换性钙、交换性镁含量间的关系。【结果】平和县319个蜜柚园土壤pH值的变幅为3.26~6.22,其平均值为4.34,有89.97%的果园其土壤pH值低于柑橘生长适宜pH值的下限(pH为5.0),其中pH<4.5的强酸性果园占67.71%。25个蜜柚园剖面土壤pH平均值不同土层的高低顺序是表土层>亚表土层>底土层,与表土层土壤的pH值相比,亚表土层和底土层pH<4.5的土壤占比分别提高了50.00%和35.71%。土壤的酸化提高了土壤交换性氢、交换性铝的含量,相关分析结果表明,土壤pH值与土壤盐基饱和度及交换性钙、交换性镁含量间均呈极显著的正相关,说明酸化会减弱土壤的保肥能力,导致土壤钙、镁元素的缺乏。蜜柚园土壤的酸化程度随蜜柚树种植年限、土壤碱解氮含量及氮肥施用量、土壤有效硫含量的增加而降低。【结论】平和县蜜柚园土壤酸化现象严重,且园土亚表土层和底土层的酸化问题较表土层更为突出,氮肥和硫肥的过量施用是引起土壤酸化的原因。鉴于蜜柚园土壤的酸化特性,文中提出了降低果园氮素和硫素的投入、结合果园深翻改土施用碱性土壤改良剂、增施有机肥等防治蜜柚园土壤酸化的措施。 相似文献
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The invasive brown marmorated stink bug, Halyomorpha halys (Stål), has become a serious pest in mid-Atlantic apple orchards. Because no decision support tools exist for H. halys management, calendar-based insecticide applications have been the only successful technique for mitigating H. halys injury in orchards. Following the identification of the two-component aggregation pheromone of H. halys, we conducted a study to determine whether biological information generated by traps baited with this pheromone and pheromone synergist could be used to make management decisions. In this study, experimental apple orchards were treated with a H. halys-targeted insecticide only when a predetermined cumulative threshold of either 1, 10, or 20 adults per trap was reached. Once threshold was reached, two alternate row middle sprays 1 week apart were triggered and the threshold was reset. For comparison, some orchards were also subjected to a weekly alternate row middle spray or left untreated as controls. At harvest, significantly less fruit injury was observed when treated weekly or using a threshold of 1 or 10 H. halys adults per trap to trigger insecticide applications. Orchards treated using a cumulative threshold of 20 adults per trap or when left unsprayed had significantly higher fruit injury. In addition, insecticide applications were reduced by 40% using a threshold of 10 adults per trap. Our results suggest that baited pheromone traps can be used as decision support tools to trigger insecticide applications when needed to mitigate risk and effectively manage H. halys in apple orchards. 相似文献
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【目的】研究红心杉连栽对地力和林分生产力的影响,为红心杉人工林的可持续经营提供数据参考。【方法】选取立地条件相同的第1(G1)、2(G2)、3(G3)代红心杉人工幼林林地为研究对象,采用空间替换时间的方法,测定第1、2、3代红心杉幼林地0~20 cm,20~40 cm,40~60 cm土层中的土壤酶活性及主要理化性质,利用主成分分析法综合评估不同代次红心杉幼林林地的土壤肥力,探究与分析连栽红心杉林地肥力下降的主要影响因子。【结果】土壤肥力的综合评价指数F值的变化范围为5.993-4.436,23个评价指标通过“降维”成3个主成分,累计贡献率达88.913%,其中,第1主成分贡献率为71.862%,第2主成分的贡献率为9.123%,第3主成分的贡献率仅有7.927%;随着连栽代次增加和土层加深,土壤水分和孔隙指标均呈降低趋势;大量元素、有效微量元素、脲酶和磷酸酶活在第1、2、3代之间均具有显著差异(P<0.05)。【结论】在当前的种植方式下,随着红心杉连栽代次的增加,土壤肥力和容蓄能力下降,脲酶、磷酸酶、全P、碱解N、速效K、有效Cu、有效Mn和有效Fe是影响土壤肥力的关键要素。 相似文献
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巨峰葡萄套袋与日灼关系的研究 总被引:2,自引:0,他引:2
巨峰葡萄套袋后,袋内温度升高,比不套袋葡萄更易发生日灼;巨峰葡萄套袋后发生日灼与气温高低、套袋时间、袋型种类、袋体通气性、遮阴条件等因素有关;套袋时避开高温期,选用色调较浅、通气条件较好的袋型,日灼较轻;创造良好的遮阴条件,可有效地减少日灼。 相似文献