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在不同时期及不同处理相结合,试验白粉病发酵液对草莓白粉病的防治效果.结果表明:各种药剂处理对白粉病都有防治效果.白粉病发酵液防治草莓白粉病的使用浓度以300~500倍为宜. 相似文献
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甜瓜白粉病的抗病基因、鉴定寄主及种质资源 总被引:1,自引:0,他引:1
综合了当前有关甜瓜白粉病抗病基因、病原菌种和生理小种及其载体种质资源的研究成果,同时介绍了抗白粉病种质资源在生理小种鉴定中的应用及13份甜瓜抗病种质的性状特征、特性。 相似文献
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以杂种榛优良品系为试材,定期检测果实、果仁及果壳中氮、磷、钾、钙元素的含量并分析其相关性.结果表明:果实和果仁中的N、P,N、K,P、K显著或极显著正相关,果仁中P、Ca,K、Ca显著或极显著正相关.果仁和果实中的N、K、Ca显著或极显著正相关,果仁和果皮中的N极显著负相关,Ca显著正相关.果仁与果实、果仁与果皮中的P不存在相关性. 相似文献
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实验中发现西瓜大粒种子自交系BW85和其小粒种子突变体F211,在授粉后7 ~ 11 d,种子的大小无显著差异,其中11 d的种子长度、宽度、鲜种子百粒质量和干种子百粒质量分别为7.93 mm、4.53 mm、4.23 g、0.32 g和8.26 mm、4.95 mm、4.54 g、0.30 g;在授粉后13 d,种子大小出现显著差异,种子长度、宽度、鲜种子百粒质量和干种子百粒质量分别为9.99 mm、6.12 mm、9.47 g、1.33 g和8.86 mm、5.32 mm、4.60 g、0.46 g。用石蜡切片的方法比较BW85与其突变体F211之间解剖结构差异,结果表明:授粉后15 d,突变体F211种子的表皮、皮下组织和厚壁组织的平均厚度分别为144.57 μm、130.53 μm、38.22 μm,均显著小于BW85的各组织厚度。对BW85(P1)与突变体F211(P2)构建的F1、F2、BC1P1和BC1 P2群体的遗传分析发现,F1和BC1P2群体均表现为与突变体相同的小粒种子性状,F2和BC1P1群体小粒种子植株与野生型大粒种子植株比例分别符合3︰1和1︰1分离比,表明该突变性状受1个显性主基因控制。 相似文献
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Dimitrios Savvas Golgen Bahar Öztekin Mahmut Tepecik Andreas Ropokis Yuksel Tüzel Georgia Ntatsi 《The Journal of Horticultural Science and Biotechnology》2017,92(3):294-302
Tomato plants (cv. Primadonna F1), non-grafted, self-grafted, or grafted onto the commercial rootstocks ‘He-man’ and ‘Maxifort’, were grown in recirculating nutrient solution. The uptake concentrations (UCs), i.e. mean nutrient-to-water uptake ratios of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B, were estimated based either on depletion from the nutrient solution or on accumulation in the plant biomass. Grafting onto both commercial rootstocks increased the total plant biomass. Hetero-grafting also increased the leaf N, Ca, and Cu concentrations but decreased those of Mg and Fe in comparison with self- and non-grafted plants. The mean UCs of N, Ca, and Cu were higher in plants grafted onto both commercial rootstocks in comparison with self- and non-grafted plants. However, hetero-grafting also raised the UCs of P, Fe, Mn, and B, because of an increased deposition of these nutrients to the roots in comparison with self-rooted plants. The method used to estimate the UCs, i.e. nutrient removal from the recirculating nutrient solution vs. nutrient recovery from plant biomass per volume unit of transpired water, resulted in similar values for N, Ca, Zn, and Cu, but had a significant impact on those of P, K, Mg, Fe, Mn, and B. 相似文献
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通过研究温室非洲菊组培苗灰霉病的症状特点和温湿度、光照、通风状况、栽植密度、施肥、虫害对该病的影响,提出相应的防治措施。结果表明:灰霉病可侵害移栽后的非洲菊组培苗的叶片、根颈和花,引起叶片、花出现坏死病斑或枯死,根颈腐烂等症状。温度低、湿度高、光照强度小于2 000 lx、栽植密度过大、通气不良、室内不清洁、偏施氮肥、虫害较多均有利于发病。防治该病的方法是以农业防治为基础,如室内清洁卫生,穴盘消毒,合理浇水,定时通风,合理施肥,控制光照,治虫防病等;化学防治为辅;提倡使用生物防治手段。该研究为温室非洲菊组培苗移栽后灰霉病的防治提供了依据。 相似文献
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陕西苹果主产区果实农药残留水平及其评价 总被引:4,自引:0,他引:4
2003~2005年连续3年对陕西20个苹果基地县的农药残留状况采用GC和HPLC方法进行了监测,并以国家规定的苹果农药最大残留限量进行了评价。结果表明,陕西苹果的农药检出率为48.6%,样品农药检出率为93.6%。检出率2%以上的农药依次为多菌灵(89.5%)、甲氰菊酯(18.7%)、六六六(16.7%)、氯氰菊酯(15.7%)、氰戊菊酯(13.4%)、乐果(11.5%)、溴氰菊酯(11.2%)、滴滴涕(9.0%)、三氟氯氰菊酯(6.7%)、百菌清(5.8%)、异菌脲(5.3%)、毒死蜱(3.8%)、敌敌畏(2.3%)、氟氯氰菊酯(2.2%)和克菌丹(2.1%)。超标的农药有多菌灵(9.50%)、敌敌畏(1.54%)、辛硫磷(0.77%)和氰戊菊酯(0.75%);经单项农药污染指数、污染指数≥0.5的样品比率、检出率、超标率的综合评价发现,陕西苹果主要污染农药为杀菌剂中的多菌灵,拟除虫菊酯类的甲氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯和有机磷农药中的敌敌畏。 相似文献
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6种农药在温室和露地辣椒上消解动态及安全使用 总被引:2,自引:0,他引:2
采用气相色谱和高效液相色谱技术,在北方露地和冬春温室条件下分别测定了丙溴磷、甲氰菊酯、吡虫啉、乙酰甲胺磷、啶虫脒、三唑酮在辣椒上的残留消解动态和最终残留量。结果表明,温室条件下丙溴磷、甲氰菊酯、吡虫啉、乙酰甲胺磷、啶虫脒、三唑酮在辣椒上的原始沉积量分别为3.13、1.11、1.23、1.29、1.67、0.38mg·kg-1,分别比露地条件下高74.9%、3.7%、17.1%、27.7%、39.2%、111.1%;施药后1d温室辣椒上的残留量分别为3.78、1.27、1.88、1.36、2.85、0.58mg·kg-1,分别较原始沉积量高20.8%、14.4%、52.8%、5.4%、70.7%、52.6%。丙溴磷、甲氰菊酯、吡虫啉、乙酰甲胺磷、啶虫脒、三唑酮在北方冬春设施辣椒上的原始沉积量明显高于露地条件下的相应值,施药后1d的残留量比原始沉积量明显增加。北方冬春设施辣椒按照推荐剂量使用啶虫脒、三唑酮是安全的,使用甲氰菊酯是不安全的;丙溴磷、乙酰甲胺磷、吡虫啉应严格按照推荐剂量使用。 相似文献
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Residential properties in the United States represent a considerable amount of land area and contain substantial tree cover. Homeowners are important decision makers in the management of city trees because they influence the structure of urban forests, and ultimately, ecosystem service potential. To better understand the perceptions, knowledge, and practices of homeowners regarding residential tree preservation, we surveyed owners of newer versus older homes in a midwestern suburb in the United States. We found that newer homeowners were younger, wealthier, and less knowledgeable about the natural aspects of their property. During the redevelopment process, they relied on professionals to make major decisions regarding tree preservation. In contrast, owners of older homes often identified as retirees and gardeners, had more knowledge of the natural aspects of their property, and were more likely to hire an arborist. Regardless of these differences, both homeowner groups expressed equal appreciation for nature, planted, pruned, and mulched their trees, experienced tree loss, hired landscaping and tree care professionals, and communicated with the City’s Forestry Section. The results of our study further clarify the role that homeowners play in decision-making during development and highlight the important relationships that exist between homeowners and urban forest professionals. 相似文献