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41.
采用抑菌圈法,对10种杀细菌剂在火龙果茎腐病病原上进行了毒力测定。结果表明:72%农用硫酸链霉素可溶粉剂、53.8%氢氧化铜水分散颗粒剂(杜邦TM)、45%代森铵水剂、47%春雷?王铜可湿性粉剂、50%福美双可湿性粉剂和3%中生菌素可湿性粉剂对火龙果茎腐病病原均有一定抑制效果。其中,45%代森铵水剂和50%福美双可湿性粉剂防治效果较好,抑制率分别达到78.88%和71.42%,其直线回归方程分别为y=2.380 2.477x,y=2.896 1.146x,EC50分别为0.4929,0.0240。72%农用硫酸链霉素可溶粉剂效果次之,抑制率达到66.67%,直线回归方程为y=1.020 1.040x,EC50值为2.5686。这3种药剂可作为火龙果茎腐病田间药效试验的首选药剂。 相似文献
42.
《Communications in Soil Science and Plant Analysis》2012,43(16):2488-2495
This article highlights the results of a long-term research project on the production of grape stalks engrafted by the desk method. The integrated impact of rootstock varieties, modes of stratification, and different substrates on vegetating vine cuttings, raised in heated greenhouses, and the capacity of their acclimatization after planting was studied. The results of the research show that rootstock variety and modes of stratification influence the output of engrafted vegetating cuttings of vines grown in pots using various substrates. In particular, the engrafted cuttings of variety Rkatsiteli produced on two rootstocks, 5 BB and 101-14, passed stratification (a) in sawdust with local electroheating, (b) on the water with its periodic change, and (c) in the layer of perlite. After preplanting preparations they were planted in pots with six different substrates: (1) soil (control); (2) perlite; (3) sawdust; (4) rice husk + soil + sand (1:1:1); (5) peat + soil + sand (1:1:1); and (6) mold + soil + sand (1:1:1). The cuttings were grown with a covered root system in a heated greenhouse for 35–40 days. Forty-day-old vegetating cuttings, after hardening, were planted into the open ground. Specialties were established during the root and shoot formation on vegetating nursery plant grafts during the rooting period. Optimal substrates for growing engrafted cuttings with a covered root system in heated greenhouses for each rootstock and stratification mode were determined. 相似文献
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Chen Qigao Feng Ya 《保鲜与加工》1993,(1)
This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance. 相似文献
46.
ABS与ASR控制算法研究及对比分析 总被引:2,自引:0,他引:2
对汽车而言,ABS是在制动过程中控制车轮的滑移率,ASR是在驱动过程中控制车轮的滑转率。为此,主要介绍了ABS和ASR的几种典型控制算法;说明了二者之间在算法中的相似和不同之处;同时,阐述了ASR的控制途径以及分析了ABS算法中的一些不足之处。 相似文献
47.
保雨灌溉技术的核心是向天空要水,与蒸发夺水,充分利用自然降水和土壤水分,满足作物需要。在作物需水不足时,提取地下水补充灌溉。三年试验结果表明,保雨灌溉比常规井灌年均节水2091mm/hm~2,增产粮食2020kg/hm~2,促进了优质高效农业的发展。 相似文献
48.
Sap flow meters based on the stem heat balance method were used to measure the mass flow rates or water use in young potted tea (Camellia sinensis L.) plants of clones AHP S15/10 and BBK35. The meters were constructed on site and installed onto the stem or branch sections of field growing plants in an experiment originally designed to study the effects of plant population density and drought on the productivity and water use of young tea clones. The objective of the study was to use the SHB method as a first attempt to use sap flow meters for determining the water use of young tea growing in the field under well watered conditions in Tanzania. The results are reported and recommendation made for further work on using the technique. 相似文献
49.
Fusheng Ma Shaozhong Kang Fusheng Li Jianhua Zhang Taisheng Du Xiaotao Hu Mixia Wang 《Agricultural Water Management》2007,90(3):190-196
The effects of water deficit in different fruit growth stages on the variation of stem sap flux of 6-year old greenhouse-grown pear-jujube trees were investigated. Treatments included sufficient water supply during the whole fruit-growing period (T1), mild water deficit during the flowering–fruit setting stage (T2), moderate water deficit during the fruit rapid growth stage (T3) and severe water deficit during the fruit maturing stage (T4). Results showed that significant compensation effect on stem sap flux after re-watering was observed in T2, but not in T3 and T4 stages. At the end of rapid growth stage, the diurnal variation of stomatal conductance generally had a similar trend as that of stem sap flux, but with a distinct midday depression from 12:00 to 14:00 p.m. In addition, a linear relationship between the relative available soil water content (RAWC) and the ratio of daily stem sap flux to that of sufficient water treatment was observed (R2 = 0.4489). 相似文献
50.
面向蔬菜病虫害视频移动获取的网络互通网关设计 总被引:2,自引:0,他引:2
网络互通问题是限制移动视频获取的关键技术瓶颈,为解决此问题,在前期关于视频分割、压缩、标注、检索等一系列研究基础上,设计出面向移动视频获取的网络互通网关,最终实现蔬菜病虫害视频的移动获取。首先对视频电话网络和IP网络的网络协议3G-324M和H.323进行了详细分析。进而基于不同网络协议原理的分析,设计出3G-324M与H.323的互通网关,包括信令网关和媒体网关两部分:信令网关负责处理信令(信号),实现视频电话网与IP网络间呼叫层面和系统层面的控制和互通;媒体网关负责数据传输,实现视频电话网与IP网络间媒体和数据层面的控制和互通。最终基于前期的研究基础和本文设计的网络互通网关,构建了蔬菜病虫害知识视频移动获取模型,实现了蔬菜病虫害的视频移动获取。此外还对视频获取模型进行对比试验,通过与传统方法的比较,证明所设计的网络互通网关和移动视频获取模型具有理论和实用价值。 相似文献