甜椒始花期氮素分配动态的研究   总被引：2，自引：1，他引：2  

隋方功  王运华  姚源喜  乌尼木仁  稻永醇二 《园艺学报》2002,29(3):238-242

 利用¹⁵N 示踪技术研究了营养液培养甜椒始花期吸收的氮素在体内的动态分配规律。结果表明: 根与果实中氮的含量在始采期以后保持稳定; 而叶片中氮的含量则随生育进程迅速下降, 盛采期时与果实和根相近, 且两倍高于茎和侧枝。始花期由根吸收的标记氮主要贮存在叶片中, 2 周后向新生器官的运转率高达50. 6%, 4 周后达到57. 1%, 6 周后为58. 0%, 说明越是新近吸收的氮素越容易被再度运转到其它器官, 随着在体内时间的延长, 氮的再运转能力逐渐降低。开花后2 周收获的果实中标记氮占始花期吸收总量的3. 24%, 第3、4、6 周分别为11. 12%, 9. 49%和4. 75%。果实是甜椒体内氮的强力库, 氮素竞争力最强。  相似文献   

高山夏秋黄瓜配套技术研究初报     

胡江  陈兵潮  姚国富  王忠兴 《长江蔬菜》2002,(1)

通过对高山夏秋黄瓜适宜种植地的选择,品种的筛选,播种期,密植程度及病虫防治等技术的试验研究,提出一套有效的高山夏秋黄瓜栽培技术,以便在同类地区推广应用。  相似文献   

Purification and characterization of an antibacterial compound produced by Agrobacterium vitis strain E26 with activity against A. tumefaciens     

H. M. Wang  H. X. Wang  T. B. Ng †  J. Y. Li 《Plant pathology》2003,52(2):134-139

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Effects of temperature on ascospore germination and penetration of oilseed rape (Brassica napus) leaves by A- or B-group Leptosphaeria maculans (phoma stem canker)     

Y. J. Huang  C. Toscano-Underwood  B. D. L. Fitt †  X. J. Hu  A. M. Hall 《Plant pathology》2003,52(2):245-255

Ascospores of both A-group and B-group Leptosphaeria maculans germinated at temperatures from 5 to 20°C on leaves of oilseed rape. Germination of ascospores of both groups started 2 h after inoculation and percentage germination reached its maximum about 14 h after inoculation at all temperatures. Both the percentage of A-/B-group ascospores that had germinated after 24 h incubation and germ tube length increased with increasing temperature from 5 to 20°C. Germ tubes from B-group ascospores were longer than those from A-group ascospores at all temperatures, with the greatest difference at 20°C. Hyphae from ascospores of both groups penetrated the leaves predominantly through stomata, at temperatures from 5 to 20°C. A-group ascospores produced highly branched hyphae that grew tortuously, whereas B-group ascospores produced long, straight hyphae. The percentage of germinated ascospores that penetrated stomata increased with increasing temperature from 5 to 20°C and was greater for A-group than for B-group L. maculans after 40 h incubation.  相似文献   

Modelling Plant Disease Epidemics     

A. van Maanen  X.-M. Xu 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(7):669-682

An epidemic is the progress of disease in time and space. Each epidemic has a structure whose temporal dynamics and spatial patterns are jointly determined by the pathosystem characteristics and environmental conditions. One of the important objectives in epidemiology is to understand such spatio-temporal dynamics via mathematical and statistical modelling. In this paper, we outline common methodologies that are used to quantify and model spatio-temporal dynamics of plant diseases, with emphasis on developing temporal forecast models and on quantifying spatial patterns. Several examples of epidemiological models in cereal crops are described, including one for Fusarium head blight.  相似文献   

Rapid detection of Phytophthora cinnamomi using PCR with primers derived from the Lpv putative storage protein genes   总被引：1，自引：1，他引：1  

P. Kong  C. X. Hong†  P. A. Richardson 《Plant pathology》2003,52(6):681-693

Phytophthora cinnamomi is an ecologically and economically important pathogen. In this study, PCR assays were developed with primer pair LPV2 or LPV3 for rapid detection and identification of this organism. Both primer pairs were selected from putative storage protein genes. The specificity of these primer pairs was evaluated against 49 isolates of P. cinnamomi , 102 isolates from 30 other Phytophthora spp., 17 isolates from nine Pythium spp. and 43 isolates of other water moulds, bacteria and true fungi. PCR with both primer pairs amplified the DNA from all isolates of P. cinnamomi regardless of origin. The LPV3 primers showed adequate specificity among all other species tested. The LPV2 primers cross-reacted with some species of Pythium and true fungi, but not with any other Phytophthora species. PCR with the LPV3 primers detected the pathogen at levels of a single chlamydospore or 10 zoospores in repeated tests. The PCR assay was at least 10 times more sensitive than the plating method for detection of the pathogen from artificially infested soilless medium, and, to a lesser extent, from naturally infected plants. PCR with LPV3 primers can be a useful tool for detecting P. cinnamomi from soilless media and plant tissues at ornamental nurseries, whereas the LPV2 primers can be an effective alternative for identification of this species from pure culture. Applications of these assays for detection of P. cinnamomi in other environments were also discussed.  相似文献   

对锰害敏感性不同的两个苹果品种枝条中锰的积累与分布   总被引：9，自引：0，他引：9  

徐圣友  姚青  王贺  张福锁  于忠范  姜学龄 《园艺学报》2003,30(1):19-22

 以对苹果粗皮病抗性不同的两个苹果品种富士(感病) 和乔纳金(抗病) 为材料,通过田间采样、室内盆栽模拟,结合组织化学、显微鉴定和X- 射线微区分析,研究了枝条内锰的累积、分布与粗皮病抗性的关系。结果表明,锰在韧皮部的含量高于木质部,感病品种含量高于抗病品种;粗皮病病斑部位存在氧化锰沉淀,韧皮部锰的局部累积和分布与病斑的分布相一致;锰在感病品种的枝条横截面上存在局部累积现象,而在抗病品种上分布较均匀。  相似文献   

“三北”防护林甘青宁类型区土地沙漠化遥感调查研究   总被引：1，自引：1，他引：1  

李振山  姚发芬 《干旱区资源与环境》1997,11(1):78-83

本文是“七五”期间“三北”防护林甘青宁类型区土地沙漠化遥感调查成果总结。该区沙漠化土地面积为２５８７８．３７ｋｍ２，其中轻度、中度、重度和极度沙漠化土地分别为３０２０．３０ｋｍ２，７２７７．４４ｋｍ２、７０８５．５９ｋｍ２ｔ和８４９５．０４ｋｍ２．文中对沙漠化土地的分布及影响因素进行了分析，最后筛出合理的农林牧用地结构。  相似文献   

雾培法根际CO2对马铃薯生长和光合作用的影响   总被引：13，自引：0，他引：13  

孙周平  李天来  姚莉  邹红藜 《园艺学报》2004,31(1):59-63

通过汽雾栽培方式对马铃薯根际连续 35d的CO2 处理表明 :温室大气处理 (CO2 380～ 92 0 μL·L-1 O2 2 1% )和室外大气处理 (CO2 380 μL·L-1 O2 2 1% )马铃薯植株的形态特征非常接近 ,其株高、叶面积、根系质量、匍匐茎数量、块茎产量以及生物量均比根际高CO2 处理 (CO2 36 0 0 μL·L-1 O2 2 1% )明显提高 ,叶片的气孔导度和胞间CO2 浓度增加 ,光呼吸速率与CO2 补偿点降低 ,叶片光系统Ⅱ功能改善 ,光合速率提高 ,植株生长发育旺盛 ,块茎产量增加 ,说明合适的根际CO2 浓度 (CO2 380～ 92 0 μL·L-1 O22 1% )可能是汽雾栽培马铃薯植株生长旺盛的重要原因  相似文献   

苹果基因组分子生物学研究进展   总被引：4，自引：1，他引：4  

姚玉新  翟衡 《果树学报》2004,21(6):586-591

借助分子标记手段苹果基因组研究取得了巨大成就,涉及苹果的抗性、生长发育、果实品质等各方面基因,综合有关文献,将其研究的主要成果,包括已发现的主要苹果遗传标记、已构建的苹果遗传连锁图谱及苹果的转基因研究进行综述,并对目前苹果基因组研究存在的问题和对策进行了分析,以期为苹果遗传育种提供参考。  相似文献