自动控温的微波消毒温室土壤装置设计

土壤消毒处理是一种被广泛采用、积极有效的防治温室病虫草害的方法。目前普遍采用的甲基溴等化学试剂熏蒸方法对人类健康和自然生态环境有害，为解决这一问题，对微波消毒土壤进行了探索。采用不同功率的微波辐射进行土壤消毒处理，并与常规加热处理效果对比，对处理后土样中微生物的杀灭效果进行检测。结果表明，采用自动控温的微波消毒温室土壤装置可以有效杀灭土壤中的微生物和草籽，控制病虫草害，改善土壤环境。采用自动控温的微波消毒温室土壤装置消毒土壤是替代甲基溴等化学试剂熏蒸及其他物理消毒土壤的较好方法。     

绿色蔬菜病虫害生物防治新技术

指出了蔬菜的病虫害防治是蔬菜种植过程中需要重视的问题,如何进行绿色蔬菜病虫害防治是当前蔬菜种植急需解决的问题,从实际出发,对蔬菜种植过程汇总病虫害的防治技术进行研究,并提出了相应的蔬菜病虫害绿色防控技术及措施,希望对绿色蔬菜病虫害生物防治工作有所启发。     

温室病虫害防治小设备的正确使用方法

详细介绍了硫磺熏蒸器、捕虫板、频振诱虫灯3种温室病虫害防治小设备的正确使用方法及注意事项。     

银杏苗期的病虫害防治

银杏叶的药用保健价值正受到广泛的重视,现各地种植栽培银杏方兴未艾。加强银杏苗期的病虫害防治,对发展银杏产业至关重要,在此将银杏苗期控制病虫害发生的有关技术措施总结如下。1　圃地选择银杏为阳性树种,喜湿怕涝耐干旱。选择地势较高,排水良好,土层深厚肥沃,酸性或微碱性的壤土或沙壤土作圃地。要注意开挖排水沟以防雨涝灾害。在低洼,积水难排地上生长的银杏往往长势不良,易感染病虫害。2　土壤消毒清洁卫生的土壤有利于减少病虫害发生,使苗木健康生长。土壤消毒可结合整地进行,每667ｍ2直接施入硫酸亚铁10ｋｇ,40%多菌灵粉剂5ｋｇ和甲…     

DC-500型塑料大棚病害臭氧防治机

DC-500型塑料大棚病害臭氧防治机，是利用高压放电激活空气中的氧气，生成臭氧的原理而设计制造的。主要用于300m2塑料大棚，可对塑料大棚气体进行全面净化和灭菌消毒。能有效地控制塑料大棚病害发生，也适用于养殖业的畜禽舍的灭菌消毒。该机由牡丹江林业科学研究所开发，并在产业化基地使用。1主要结构及工作原理该机主要由交直流两输出电源、臭氧管、除尘除湿电极板、轴流风机及定时器等组成。旋动定时器、轴流风机和高压电源同时开始工作，这时大棚内的气体进入臭氧管区域，在臭氧管放电的作用下，空气中的氧气被激活为臭氧，臭氧随空…     

姜荷花的形态特征及在白云禁毒主题公园的花境应用

姜荷花Curcuma alismatifolia要种植在光照充足且排水良好的环境,种植时需消毒土壤及种球,使用缓释复合肥,保持土壤湿润,并及时防治炭疽病及蝗虫等病虫害.参考泰国农业部对姜荷花新品种的测试内容,对广州白云禁毒主题公园中种植的10个姜荷花品种的叶片、花序、株高等进行了观察测量.结果表明,10个品种的株高、冠...     

大棚蔬菜种植技术及病虫害防治策略

指出了在当前的大棚蔬菜种植过程中,因受天气因素、气体危害以及棚内温度控制不当等各种因素的影响,会对大棚蔬菜种植效率造成一定的影响。对大棚蔬菜种植技术进行了探讨,提出了病虫害防治策略,以期提供参考。     

苏云金杆菌在山西地区森林病虫害防治中的应用研究

苏云金杆菌属于国际上应用最为广泛的生物杀虫剂,其在农业、蔬菜、果树、森林病虫害防治中发挥着十分重要的作用。结合山西地区森林资源现状及特点,对苏云金杆菌在山西地区森林病虫害防治中的应用进行研究。对苏云金杆菌致病机理及用药方法进行探索,结合山西地区森林病虫害情况,对苏云金杆菌在森林病虫害防治中的作用进行研究。实践证明,根据实际情况,合理应用苏云金杆菌,可以有效防治森林病虫害发生,其应用综合效益明显,市场前景广阔。     

苦参碱烟剂熏蒸防治温室粉虱效果初探

粉虱(Aleyrodidae)是一种世界性害虫,对我国的农林业造成了严重危害,鉴于化学防治的缺点,本文主要应用苦参碱烟剂对温室粉虱进行防治,结果表明:苦参碱烟剂(1.2%烟碱·苦参碱)熏蒸是防治温室粉虱的一种十分有效的措施。在粉虱虫口密度较小时(6头/株),一次熏蒸即可;虫口密度较大(6头/株)时,可在3天后进行第2次熏蒸,并根据熏蒸结果情况适当增加熏蒸次数,最终完全杀死粉虱。     

黄陂区绿色有机蔬菜种植研究

指出了武汉市黄陂区拥有广阔的农业用地,为提高收益当前开始大批量种植绿色有机蔬菜,并开发出了专业的管控体系。我国当前已经制定了绿色有机蔬菜的生产规定,种植过程中必须考虑这类规定的实际落实方法,此外蔬菜种植过程必须考虑当地的病虫害爆发规律和种类、温度变化情况、当地的空气湿度等自然环境参数。为此,提出了黄陂区绿色有机蔬菜的种植技术和具体方法,以促使当地有机蔬菜种植系统稳定运行。     

大棚草莓重茬栽培土壤根际菌物和线虫数量变化的研究

通过比较大棚重茬草莓的幼果期、盛果期和采果后期及不同土壤处理（太阳能处理、原美草莓重茬病防治剂处理、溴甲烷熏蒸处理）的根际微生物的数量和种类变化,证实了原美防治剂的生态安全性及土壤处理效果.结果表明,大棚草莓根际土壤中真菌数量随着草莓发育进程的推进有增大趋势,细菌数量先升高后降低呈单峰曲线分布,放线菌数量盛果期有所上升,到采果后上升幅度较大.不同土壤处理后比对照土壤根际中细菌富集,真菌、放线菌受到抑制,土壤由＂真菌型＂土壤向＂细菌型＂土壤转化.用原美草莓重茬病防治剂处理过的土壤比对照土壤真菌少,约为对照的1/10,且与其他处理无差异;在盛果期放线菌数量太阳能、原美草莓重茬病防治剂、溴甲烷处理分别比对照减少85.9%、84.0%和71.1%;细菌数量在盛果期比对照土壤高2～3倍.同时,通过淘洗法测定了土壤处理对根际线虫数量的影响,其数量变化与土壤处理无明显规律.     

Bestimmung von Schwellwerten für die Schädigung von tierischen und pflanzlichen Organismen durch Phosphorwasserstoff und Methylbromid II. Untersuchungen an Brunnenkresse (Nasturtium officinale) und Kopfsalat (Lactuca sativa capitata)

In stored-product fumigations mainly methyl bromide and phosphine are used. These toxic gases can contaminate the environment. A harmful effect on vegetable and animal organisms cannot fundamentally be excluded. The threshold concentrations of methyl bromide and phosphine in air were determined for water cress and lettuce. These species were chosen because of their high sensitivity representing other species of plants. Whereas lettuce was harmed already at about 400 mg CH₃Br/m³, on water cress plants at 1400 mg CH₃Br/m³ external harmful changes couldn't be found. The threshold concentration for lettuce treated with phosphine is between 3 and 8 mg PH₃/m³. There is no difference between the development of water cress seeds in soil, which had been treated for 3 days with 4 mg–36g CH₃Br/m³ or 20–1400 mg PH₃/m³ and not treated soil. At high PH₃-concentrations a higher growth of water cress plants occurred.     

Effects of short-term ozone exposure and soil water availability on the carbon economy of juvenile Douglas-fir

Effects of ozone and soil water availability on partitioning and translocation of assimilates were studied in three-year-old Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) seedlings exposed, in separate experiments, to 0 and 106 or 0 and 514 micro g m(-3) ozone for 8 h day(-1) for 9 days. The dynamics of carbon from assimilated (14)CO(2) were followed. No interactions between ozone and soil water content were observed. Total net uptake of carbon was reduced by low soil water content, but was unaffected by ozone. Both ozone and low soil water content increased the amount of (14)C-photosynthates retained in the current-year needles. Total starch content in old and current-year needles was unaffected by ozone, but was reduced by low water availability. Translocation of carbon to the root-soil compartment was additively affected by ozone and low soil water content. The results suggest that dry periods in summer combined with high ozone concentrations cause the greatest reduction in the supply of carbon compounds to the root-soil compartment.     

四川山丘区抑螺防病林类型、建设模式与减量特性研究

本文调研了四川山丘区林业血防工程建设中抑螺防病林的生长状况、布局与林内外小气候特征。结合抑螺防病林与沟渠、沟溪、河流间关系,将其总结为9种类型,并提出5种建设模式。据测定,抑螺防病林能降低地表气温1.38℃,减少光照1 049.89×10 lux,降低土壤表层温度7.43℃(0 cm～5 cm土层)和5.28℃(5 cm～10 cm土层),具有减量特性。山丘区林业血防安全体系需要从天然水系、人工沟道等水系(流)网络上建设抑螺防病的网状森林廊道。     

Comparison of methyl bromide and herbicide effects on endomycorrhizal formation,seedling production,and weed control in sweetgum seedbeds

Sweetgum seedlings were grown in fumigated and nonfumigated nursery plots where equal portions were treated with a preemergence application of 1.1 kg/ha of trifluralin and a postemergence application of 1.7 kg/ha of napropamide. Methyl bromide at 478 kg/ha significantly decreased average root dry weight. Endomycorrhizal formation on one, two, and three month-old seedlings was not significantly decreased by fumigation or herbicide application. Weeding times for herbicide plots were less than half that for fumigated plots. These results show that herbicides can provide better control of annual weeds and produce better sweetgum seedlings than fumigating with methyl bromide.     

杂交竹白纹羽病生防菌的筛选与应用

本文以健康杂交竹根际土为对象,在稀释平板法获得25株芽孢杆菌基础上,采用牛津杯法、打孔法测定两株目标生防菌发酵滤波对白纹羽病菌的抑制活性,筛选出最优B2菌株,盆栽试验证明该菌株有较高生防潜能,形态学与生理生化鉴定为蜡样芽孢杆菌（Bacillus cereus）.田间试验表明该菌剂100倍～200倍（体积比）稀释度沿根系幅面灌根,每株100 mL,每年春季施用一次,可预防白纹羽病发生;50倍～100倍（体积比）稀释度沿根系幅面灌根及附近土壤淋灌,每株200 mL,春、夏各一次,连续3a,可有效治疗白纹羽病,总体效果优于甲基托布津.     

森林与生态环境(上)

本文介绍了目前国际社会注目的10个生态环境问题:温室效应加剧、生物多样性锐减、大气臭氧层损耗、水资源危机、水土流失、沙漠化扩大、土壤退化、噪声污染、大气污染和酸沉降、海洋污染,简述了生态环境恶化带来的严重后果,并重点阐述了森林与温室效应、生物多样性保护、大气臭氧层损耗、水资源危机的关系。     

Effects of compaction and water content on lodgepole pine seedling growth

Soil disturbance by heavy machinery usually causes a decrease in porosity and an increase in soil strength, which may limit access to nutrients and compromise seedling survival and growth. This study used a soil strength and a greenhouse experiment to assess the impact of compaction on lodgepole pine (Pinus contorta Dougl. Ex. Loud. var. latifolia Engelm.) seedling growth and the degree to which soil water influences the effects of compaction. A silt loam soil was collected from a forest landing in the central interior of British Columbia (BC) in the Sub-Boreal Spruce Biogeoclimatic zone. The silt loam soil was used in a soil strength experiment where soil with four water content levels (0.10, 0.18, 0.27, and 0.36 cm³ cm⁻³) was packed into 0.21 cm³ cores with three levels of compaction (74, 79, and 84% of maximum bulk density (MBD)). Soil strength was strongly affected by compaction and water content. In the greenhouse experiment, three water content levels (0.10–0.15, 0.20–0.30, and 0.30–0.35 cm³ cm⁻³) and three levels of compaction (67, 72, and 76% of MBD) were applied to soil in pots and 1-year old lodgepole pine seedlings were grown in the pots. Soil strength was highest (1275 kPa) for the high compaction and dry water content treatment in the greenhouse experiment. Though the soil strength for this treatment did not exceed 2500 kPa, the effect of compaction on growth was noticeable, with a decrease in diameter growth, total shoot mass, and new root mass as compaction increased at the dry water content. At dry water content and high compaction, foliar nutrient concentrations were greatest. Generally, water content had a greater impact on seedling growth than did compaction, at the levels of compaction used in this study. This study indicates that if there is a critical value for mechanical impedance of the conifer roots, it likely occurs below 2500 kPa. Our results are consistent with the explanation that soil strength incrementally affects root growth below 2500 kPa for this soil type. Expensive rehabilitation techniques may not be needed on lightly disturbed soils similar to that used in this study if soil water content is high enough throughout the conifer growing season to alleviate the effects of compaction on soil strength.     

Ozone uptake, water loss and carbon exchange dynamics in annually drought-stressed Pinus ponderosa forests: measured trends and parameters for uptake modeling

This paper describes 3 years of physiological measurements on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) growing along an ozone concentration gradient in the Sierra Nevada, California, including variables necessary to parameterize, validate and modify photosynthesis and stomatal conductance algorithms used to estimate ozone uptake. At all sites, gas exchange was under tight stomatal control during the growing season. Stomatal conductance was strongly correlated with leaf water potential (R2=0.82), which decreased over the growing season with decreasing soil water content (R2=0.60). Ozone uptake, carbon uptake, and transpirational water loss closely followed the dynamics of stomatal conductance. Peak ozone and CO2 uptake occurred in early summer and declined progressively thereafter. As a result, periods of maximum ozone uptake did not correspond to periods of peak ozone concentration, underscoring the inappropriateness of using current metrics based on concentration (e.g., SUM0, W126 and AOT40) for assessing ozone exposure risk to plants in this climate region. Both Jmax (maximum CO2-saturated photosynthetic rate, limited by electron transport) and Vcmax (maximum rate of Rubisco-limited carboxylation) increased toward the middle of the growing season, then decreased in September. Intrinsic water-use efficiency rose with increasing drought stress, as expected. The ratio of Jmax to Vcmax was similar to literature values of 2.0. Nighttime respiration followed a Q10 of 2.0, but was significantly higher at the high-ozone site. Respiration rates decreased by the end of the summer as a result of decreased metabolic activity and carbon stores.