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2006年对永安市区行道树天竺桂上的日本龟蜡蚧采用树干基部注射及叶面喷雾防治试验,结果表明:注射防治法效果较差,不宜使用;而喷雾法4种可湿性粉剂均有较好效果,防治效果达75.6%~93.3%之间。从防治效果与成本两方面考虑,防治时应优先选用杀灭2 000倍液、删虫1 000倍液,其次是利克虱1 000倍液,最后是欧贝1 000倍液。防治时机应掌握在初孵若虫期进行。 相似文献
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柏大蚜生物学特性及防治技术 总被引:2,自引:0,他引:2
柏大蚜(Cinara tujafilina)是侧柏的主要害虫之一,在新乡市1年发生17-22代,以卵和无翅胎生雌蚜越冬,为留守型。经多年防治试验,用有机磷类农药树冠喷雾或树干基部打孔注射50%久效磷液,防治效果均达90%以上。文中还介绍了该虫的形态特征和生物学特性。 相似文献
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栓皮栎波尺蛾Laveran nisfilipjeri Wehril是栎类树木的重要食叶害虫。该虫在河南省西峡县一年1代,以蛹在地表层越冬,蛹期长达9个月。采用久效磷树干涂环;250倍敌杀死叶面喷雾及敌马烟剂地面熏杀,防治效果可达85%。 相似文献
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树干注射化学药剂防治松纵坑切梢小蠹试验 总被引:3,自引:0,他引:3
使用40%氧化乐果乳油、50%甲胺磷乳油两种内吸性杀虫剂树干注射防治松纵坑切梢小蠹的表明:树干注射化学药剂对防治蛀梢期小蠹成虫有较好的效果。两种药剂平均杀虫效率均70%以上,50%甲胺磷的效果略高于40%氧化乐果。药剂对云南松树梢和针叶均无不良影响。以8月采取每孔注射1.5mL的40%氧化乐果乳油或50%甲胺磷乳油的防治效果最佳,杀虫率达到87%以上。 相似文献
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We examined the water status of Hinoki cypress, Chamaecyparis obtusa (Siebold & Zucc.) Endl., trees after a severe typhoon to determine possible causes of the decline and dieback that can occur in what appear, at first, to be healthy trees in typhoon-damaged forest stands. We found that in apparently healthy trees in a storm-damaged stand, the water conducting area of the trunk cross section was greatly reduced compared with that of similarly sized trees in a nearby undamaged stand. Although leaf specific hydraulic resistance (Wl) from soil to leaf and from trunk to leaf was higher in trees from the storm-damaged than the undamaged stand, Wl values from soil to root were similar. Diurnal patterns in the rates of change in trunk diameter differed between trees in the damaged and the undamaged stand. We conclude that increased aboveground hydraulic resistance caused by a reduction in trunk water conducting area could be a major reason for the decline and dieback of apparently healthy trees in typhoon-damaged stands. 相似文献
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影响甜柿坐果率因素试验研究初报 总被引:1,自引:0,他引:1
为解决甜柿坐果率低的问题,采取了人工授粉、花期喷施赤霉素和主干环剥等技术措施。结果表明:人工授粉、花期喷施赤霉素和主干环剥与对照比较分别高24.28%,17.15%,13.87%,均能显著提高甜柿的坐果率。虽然花期喷施赤霉素和主干环剥的平均单果重显著小于对照,但甜柿单位面积产量与对照相比仍有显著提高。 相似文献
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泡桐大袋蛾防治指标的研究 总被引:1,自引:0,他引:1
本文通过测定大袋蛾(ClaniavariegataSnelen)幼虫食量、泡桐蓄叶量、模拟危害损失量等试验得出:每头幼虫一生平均食叶量为3780~3980cm2,雌虫比雄虫高407%;7、8月份泡桐蓄叶量与胸径分别为Y7=05319D16949和Y8=11327D14199的幂函数回归关系;在模拟危害率30%以下时,对当年泡桐生长无补偿作用,对翌年泡桐生长有补偿作用;7、8月份材损率与危害程度分别为Y7=07200X-00177和Y8=07571X-00146的线性回归关系。根据我国泡桐大袋蛾防治方法技术水平的不同,提出了大袋蛾危害15、20、25、30、35cm胸径泡桐时,采用人工注药的防治指标:百叶平均虫口分别为280、170、117、85、67头;采用飞机超低容量喷洒灭幼脲的防治指标:百叶平均虫口分别为188、124、90、70、56头。 相似文献
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Effects of trunk girdling on seasonal patterns of xylem water status, water transport and woody tissue metabolic properties were investigated in ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.) trees. At the onset of summer, there was a sharp decrease in stomatal conductance (g(s)) in girdled trees followed by a full recovery after the first major rainfall in September. Eliminating the root as a carbohydrate sink by girdling induced a rapid reversible reduction in g(s). Respiratory potential (a laboratory measure of tissue-level respiration) increased above the girdle (branches and upper trunk) and decreased below the girdle (lower trunk and roots) relative to control trees during the growing season, but the effect was reversed after the first major rainfall. The increase in branch respiratory potential induced by girdling suggests that the decrease in g(s) was caused by the accumulation of carbohydrates above the girdle, which is consistent with an observed increase in leaf mass per area in the girdled trees. Trunk girdling did not affect native xylem embolism or xylem conductivity. Both treated and control trunks experienced loss of xylem conductivity ranging from 10% in spring to 30% in summer. Girdling reduced xylem growth and sapwood to leaf area ratio, which in turn reduced branch leaf specific conductivity (LSC). The girdling-induced reductions in g(s) and transpiration were associated with a decrease in leaf hydraulic conductance. Two years after girdling, when root-to-shoot phloem continuity had been restored, girdled trees had a reduced density of new wood, which increased xylem conductivity and whole-tree LSC, but also vulnerability to embolism. 相似文献
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树木注射伤害分入针、注射及退针时的物理损伤,由药物—树木本身的生物化学反应造成的伤害、注射技术使用不当所引发的伤害5种类型。树木注射伤害是可以控制的,防止发生树木注射伤害必须选用正确的树木注射技术路线、合理控制高压注射的速度,需特别注意高压注射装置的针头密封以及进退针的方式,并选用安全、有效的药物。 相似文献
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对20年生北美鹅掌楸人工林生产力及碳氮积累研究表明:北美鹅掌楸福建北部生长潜力较大,树高达15.61~24.54m,胸径为21.37~33.31 cm,单株材积为0.259~0.990 m3。北美鹅掌楸对立地条件敏感,Ⅰ类地树高、胸径、材积生长分别比Ⅲ类地增加63.62%、55.90%、281.91%;全树总生物量可达580.27 t.hm-2,各生长器官的生物量大小顺序为树干>树枝>树根>树皮>树叶,分别占到总生物量的58.80%、20.61%、11.94%、5.58%和3.07%;树干、树叶、树皮、树枝、树根碳含量分别为52.13%、50.61%、49.20%、46.85%、45.34%,氮含量分别为0.72%、0.91%、0.96%、0.88%、0.83%;全树碳总积累量可达290.26 t.hm-2,树干、树枝、树根、树皮、树叶分别为177.86、56.02、31.43、15.92、9.03 t.hm-2;全树氮总积累量可达4.56 t.hm-2,大小顺序依次为树干>树枝>树根>树皮>树叶。 相似文献
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为了解PP333对盆栽蚊净香草观赏效果的影响,采用不同浓度的PP333对盆栽蚊净香草进行了盆土浇施和叶面喷施处理,结果表明,盆土浇施50-200mg/L,叶面喷施250~500mg/L的PP333能有效地提高盆栽蚊净香昌的观赏效果,而盆土浇施400mg/L以上,叶面喷施1000mg/L以上的PP333会造成不同程度的药害。在适宜的浓度下,盆土浇施效果优于叶面喷施。 相似文献
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森林生物量是反映森林生态环境的重要指标,是研究许多森林问题和生态问题的基础。本研究以河北省油松林调查数据为基础,借助Excel、SPSS11.0和ForStat统计分析软件对河北省油松单木生物量和分配格局进行分析,结果表明:(1)油松单木胸径与树高、树叶生物量、树干生物量、树枝生物量、树根生物量和全树总生物量均呈极显著正相关;树高与胸径、树干生物量、树枝生物量、树叶生物量、树根生物量和全树总生物量呈极显著正相关。(2)各调查地油松各器官的生物量,其中树干的平均值为50.55%,树枝的平均值为18.93%,树根的平均值为15.52%,树叶的平均值为15.00%。(3)随着单木生物量的增加,单木各器官树干、枝条和树叶的生物量分配比例保持相对稳定。 相似文献