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沈阳沈北新区蔬菜大棚生产期气候变化及气象灾害对策 总被引：2，自引：1，他引：1
[目的]研究沈阳沈北新区蔬菜大棚生产期气候变化及气象灾害对策。[方法]利用沈阳沈北新区近38年气象观测资料,采用常规数理统计方法,分析沈北新区蔬菜大棚生产期气候变化,并探讨气象灾害天气的应对措施。[结果]近38年来,沈北新区光照条件一般,冬季平均日照时数较短（551 h）,呈缓慢减少趋势,但降幅并不明显;沈北新区蔬菜大棚生产期气温倾向率0.371℃/10 a,冬季气温倾向率0.313℃/10 a,气温虽呈升高趋势,但波动幅度较大,让生产管理难以控制;较寒冷期（11～3月）历年降水量、阴天日数呈增加趋势,对蔬菜大棚生产影响较大;低温寡照阴天是该区冬季气候特点,对发展蔬菜大棚产业不利,冬季增加取暖措施有望正常发展。[结论]研究结果可为当地设施农业的发展提供科学依据。 相似文献
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The whitefly Bemisia tabaci is a serious pest of eggplants, especially those grown undercover in polytunnels and greenhouses. Due to increasing levels
of resistance of B. tabaci to a wide range of insecticides, there is now an urgent need to explore other non-chemical methods of control. In this study,
Serangium parcesetosum, a ladybird, was evaluated as a possible biological control agent of B. tabaci’s winter and spring populations which infests eggplants grown undercover in Turkey. It was found that in winter, S. parcesetosum failed to control B. tabaci, even when the ladybird population was augmented six times over the course of the experiment. This contrasted with that observed
in spring when, with only one introduction of the ladybird, control of the pest was gained within 3 weeks after release. In
spring, the B. tabaci population in the cages receiving two and four S. parcesetosum adult per plant showed 56 and 53% reduction, respectively. The percent reduction in B. tabaci population rose to 98.6 and 98.3% in both cages, respectively, by the end of experiment. It is suggested that release of
S. parcesetosum against B. tabaci during spring months may be offered as an alternative solution to increase implementation of biologically based B. tabaci management. In winter other biological control agents are needed and these need to be further explored. 相似文献
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[目的]分析拉萨市周边大棚土壤有机质含量。[方法]以拉萨市周边主要县区的大棚为研究对象,采用重铬酸钾氧化-硫酸消化法对土壤样品进行测定。[结果]拉萨市周边大棚中不同土层有机质含量存在一定差别,深层土壤中有机质含量相对较低;不同栽培方式大棚中土壤有机质含量不同,与温室大棚相比,相同土层普通大棚有机质含量相对较低。土壤有机质含量低于临界值(20.00 g/kg)土样占61.33%,处于较高水平(≥30.00 g/kg)仅为10.64%。不同县区大棚土壤有机质含量由高到低依次为达孜县、堆龙德庆县、曲水县。[结论]拉萨市周边大棚土壤有机质含量以中低水平为主,为中低等肥力土壤。 相似文献
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