论文标题:苹果园生草与释放天敌对害虫的控制效应
Studies on the Effect That Planting Grass and Releasing Natural Enemies Has the Pests under Control in the Orchard
论文作者 姜玉兰
论文导师 李照会,论文学位 硕士,论文专业 农业昆虫与害虫防治
论文单位 山东农业大学,点击次数 166,论文页数 51页File Size4493k
2003-10-01论文网 http://www.lw23.com/lunwen_5160152/ 果园;植草;天敌;害虫;控制作用
Grass-planting orchard; natural enemy; pest; Control effect
本论文针对目前发展生态农业的要求,主要研究了苹果园植草对果园生态系统的影响,对天敌的保护和增殖作用及对害虫的控制作用,同时研究了释放天敌对害虫的控制作用,以及果园施药对天敌的不利影响。主要内容和结论如下: 1、苹果园植草后,节肢动物的物种丰富度、多样性指数和均匀性指数均明显大于清耕区。通过植被的多样化,增加了生物的多样性,使天敌群落发生改变,果园生态群落得到稳定,有利于维持果园的生态平衡。 2、根据苹果园害虫和天敌发生的特点,筛选出与天敌繁衍关系密切的有益杂草,在果树行间种植苜蓿和三叶草,通过果园植被的多样化改善果园生态环境,使之有利于天敌的繁衍,而不利于害虫的发生,根据益害比和害虫防治指标确定防治措施,尽量少用杀虫杀菌剂,充分发挥天敌的控制作用,可以达到持续有效地控制害虫的目的。研究表明,果园中种植苜蓿、三叶草,园内天敌的发生高峰期提前了7～10天,持续时间延长了30天以上;果园内天敌的种类和数量显著增加,从天敌总量的增长来看,三叶草区较清耕区天敌增加54.03%,苜蓿区增加86.53%,靠麦田苜蓿区则增加165.51%。果园植草后天敌对害虫的控制作用非常明显,其中,苜蓿区天敌较多,三叶草区天敌数量次之,而靠近麦田苜蓿区的天敌数量最多,果树上害虫最少,控制效果最好。果园植草后对苹果蚜虫的控制效果在72.26%～85.31%,对害螨的控制效果在32.59～66.86%,对其它害虫的控制效果在45.64～57.16%。苜蓿区天敌数量较多是由于高大的牧草隐蔽性好,可以为天敌提供更好的栖息场所,而且苜蓿区对害螨的控制效果(66.86%)好于三叶草区(32.59%),因此在胶东地区苜蓿比三叶草更适于做苹果园的有益植被。靠近麦田的苜蓿区,天敌数量较其它区多,说明果园内的天敌部分是由麦田转移来的,麦田内天敌的转移大多发生在麦收前,麦收后天敌的转移较少。果园植草后,天敌转移的数量明显增多。因此苹果园害虫的综合治理不是孤立的,必须与周围环境密切结合,摸清天敌在果园生境里的迁移规律,采用果园植草等技术招引助迁天敌。同时农作物收获后应在田间停留一段时间,以利于天敌的转移。 3、有益杂草是天敌昆虫越冬、栖息和大量增殖的主要场所,对天敌有保护和增殖作用。虚伪钝绥螨主要在地表覆盖
This paper studied the variety and amount of the arthropod in grass-planting orchard and no-grass orchard releasing Amblyseius fallacies in clover-planting orchard, and the control effect of pests .The main contents and conclusions are as follows:Under the control of the ecosystem in the orchard, the natural factors were very important to the occurrence and damage of the pests. The comprehensive effect of natural enemies and plant resistance went beyond 80%(pimonte 1992). After planting grass in the orchard, the natural enemies enjoyed a good living environment. Diversity, richness, evenness of community were all higher than that in no-grass orchard and it can enhanced the stability of ecosystem, so it was easy to keep ecological balance in grass-planting orchard.By investigation, there were a great number of natural enemies in the grass-planting orchard such as Aranea, Coccinella septempunctata, Scolothrips sexmaculatus and etc. It was very obvious that the variety and density of natural enemies in the grass-planting orchard was more than that in the no-grass orchard. Conversely the amount of pests decreased greatly.There were a great number of natural enemies in the wheat field. Before the wheat harvest, they began to transfer to the orchard, So protecting natural enemies in nearby wheat field was a feasible measure to increase natural enemies in the orchard.Applying agriculture chemical was the main reason that the pests were rampant again. The natural balance was destroyed after applying agriculture chemical, the amount of pests decreased rapidly if the natural environment was fit, while the amount of natural enemies was difficult to return to normal.By investigation on occurrence time of local natural enemies and pests in the clover-planting orchard, the local natural enemies couldn"t be in complete control of the pests, so the research on releasing suitable natural enemies was very necessary.Release was made in the apple orchard in Qingdao city, Shandong province. Amblyseius fallacies could survive, develop, and give a good control of pest mite Panonychus ulmi. The number of the pest mitewas 22.45 female adult/leaf on release trees, while 55.52/leaf on check tree in mid-July, the peak time of abundance.Several kinds of predatory natural enemies built up in released plot and check plot free from chemical spraying. Among which, Stethorus punctillum was dominant species, it played an significant role in the late season"s spider mite control, especially on the check tree. Very few natural enemies were found in the chemical control orchard.The OP resistance in the A. fallacies strain studied had declined due to the long laboratory rearing. Therefore, insecticide spraying was the major factor affecting the population growth of A. fallacies.Some other problems regarding the potential of utilizing the predator in apple orchards in Shandong area were discussed.
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