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1.
竹锈褐斑病由螨类为害引起,笔者于2008年3月至2009年12月对南京地区竹锈褐斑病发生状况进行了调查。结果表明:该病主要危害3个属共12种竹种,病害的发生与竹林地被物、竹种生长状况、竹种和竹林环境状况有密切关系。7月上中旬发病达到高峰,7月下旬至8月上旬螨类种群数量下降;8至9月气温仍然较高,同时降雨量减少,虫口数量有所回升。螨类1年发生多代,世代重叠严重。  相似文献   

2.
竹类产业被誉为21世纪的朝阳产业,具有发展空间和潜力.本文首先介绍山东省的自然环境状况,竹类资源在山东省的历史和现状情况,提出了一些针对山东省来说,竹子利用的研究方向和利用方法,以期为竹类植物的生态与进化、引种与栽培、开发与利用等方面的研究提供参考.  相似文献   

3.
南京地区竹类病害发生状况及防治对策   总被引:1,自引:1,他引:0  
为查清南京地区竹类病害发生流行状况,笔者通过野外路线踏查和标准地调查相结合,于2007年5月至2009年3月对该地区主要散、混生竹种系统开展了病害发生种类和危害状况调查,并对竹类病害发生流行的主导因子进行了分析。共调查竹种18属107种(含种下等级),发现竹类病害15种,其中真菌性病害13种、非侵染性病害1种和螨害1种。发生较严重的病害为竹丛枝病(Aciculosporium take)、竹叶枯型丛枝病(Phaeosphaeria bambusae)、刚竹秆褐腐病(Fusarium spp.)、竹叶锈病(Puccinia spp.,Uredo ignava)、竹叶锈褐斑病(Schizotetranychus nanjingensis)等,对竹类生产危害和影响较大。竹类病害的发生流行与竹种、环境条件及经营管理关系密切。在此基础上,提出了在竹类植物栽培过程中要做到适地适竹,科学管理,加强优良竹种选育以及竹类病害研究和检疫等的防治对策。  相似文献   

4.
为了丰富柳州城市园林绿化竹类植物的种类,2006年至2009年,在柳州市鹧鸪江苗圃内进行32种观赏竹引种栽培试种,综合评价引种竹种的抗逆性、生长状况和观赏性状稳定性,筛选出适合在柳州市生长的25个观赏竹品种。这25种观赏竹可以在柳州及周边地区推广种植。  相似文献   

5.
刘良盛 《广东科技》2014,(16):155-156
大头典竹是典型笋用竹种。通过开展大头典竹的埋杆(节)育苗和造林试验,初步探索出一套较为经济,周期较短,适应规模种植大头典竹的育苗和造林技术方法,以指导大头典竹的笋用竹林基地发展建设。  相似文献   

6.
重瓣黄刺玫在新疆未见有分布 ,石河子园林研究所自1994年开始引种栽培 ,对该树种的形态特征、物候特性、生长周期、引种适应性、繁育和栽培的多项研究 ,其表现出较强的适应性和较好的园林观赏性 ,在引种区有较好的推广应用前景  相似文献   

7.
【目的】探究海拔对金佛山方竹生长发育的影响,为金佛山方竹引种及高效培育技术提供参考。【方法】以贵州顶箐山和箐坝山的金佛山方竹林为研究对象,在试验林低、中低、中高、高海拔处分别布设样方,观测并比较笋期、幼竹高生长、成竹生长等指标。【结果】试验区金佛山方竹笋期为8月下旬至10月上旬,不同海拔处日出笋量的动态变化均呈典型的正态分布格局,出笋始发及结束时间、发笋高峰期均随海拔的增高而提前,但总出笋量差异较小;各海拔下幼竹高生长均符合“慢—快—慢”的“S”形曲线,Logistic回归方程模型能较好地拟合其生长节律,决定系数(R2)均达0.99以上。随着海拔的升高,幼竹高生长持续时间有所下降,但平均生长速率及最大生长速率总体呈上升趋势;成竹胸径和全高分别在中高和高海拔处最大,均在低海拔处最小,较高海拔处竹林生长优于较低海拔处。【结论】海拔对金佛山方竹的笋期及幼竹生长有明显影响,较高海拔处竹林出笋更早,生长状况更好。  相似文献   

8.
初步探讨了湖南吉首地区野生观赏植物的区系地理成分.该地产野生观赏植物79科,152属,280种,它们的区系地理成分有12个分布类型.根据“区系发生法”的引种理论,阐明了这些野生植物可以引种栽培的范围。  相似文献   

9.
《应用科技》1999,(8):36
该项目在查清浙江全省及全国竹子主产区的竹种资源的基础上,开发出早竹、白哺鸡竹、黄甜竹等优良笋竹种,并总结出一整套早出丰产栽培管理技术.上述笋用竹种具有产量高、笋期长、品味好等特点,适宜在我国南方各省市普遍推广栽种.该项目主要推广早竹、白哺鸡竹的早出丰产栽培技术,幼林经几年后可成林,一般每亩留竹600~800株,母竹健壮、结构合理即可进行覆盖,使地表温度保持在10℃以上,并适时施肥、浇水.  相似文献   

10.
土壤条件、气候是影响干热河谷荒山竹子造林成活的两大因子,试验表明部分竹种在干热河谷荒山土层深厚的沟谷地段造林有较强的适应性。我们总结出适宜干热河谷竹子造林的最佳时间,另外还进行了干热河谷造林竹种初步筛选以及造林时施保水剂和不施保水剂的竹子后期生长情况对比试验。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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