断根对菊芋生长速率和物质积累速率的影响     

朱铁霞  王琳  高阳  门果桃  乌日娜  高凯 《北方园艺》2016,(21):28-31

菊芋(Helianthus tuberosus)块茎作为生物乙醇和菊粉产业的主要原材料,研究提高菊芋块茎生物产量和品质成为学者们关注的热点问题。通过营养期对菊芋进行断根处理,探讨生长速率和各器官物质积累速率对断根的响应情况,以期为菊芋块茎高产栽培提供理论依据。结果表明:断根有效地提高了块茎膨胀高峰期(9月21日至10月20日)的物质积累速率,能够有效地提高块茎产量;叶片、茎秆和花的物质积累速率随着断根时间的延长呈现先增加后降低的变化趋势,其中叶片物质积累速率的升高,也是断根提高菊芋块茎产量的主要原因;重度断根处理(20cm)条件下菊芋生长速率呈现先增加后降低的变化趋势,其它各断根处理对菊芋生长速率没有显著改变。  相似文献   

Histological changes in the cell wall structure during wood decay by Trametes hirsuta and Trametes versicolor in neem (Azadirachta Indica A. Juss)     

Isha M. Bhatt  S. Pramod  Rina D. Koyani 《Journal of Sustainable Forestry》2013,32(8):578-590

ABSTRACT

Structural alterations in the wood cell walls of neem inoculated with by Trametes hirsuta and T. versicolor were studied by microscopic methods. In vitro decayed wood showed extensive weight loss of test blocks (26.7 and 41.38% by T. versicolor and T. hirsuta, respectively) at the end of 3 months. Selective delignification in the initial phase followed by simultaneous removal of lignin was evident in test blocks inoculated with both the species. The separation of middle lamellae and patches of cellulosic polysaccharides stained blue with Astra blue in the delignified region of the fiber wall during early stages indicates selective mode of decay. In contrast, the occurrence of erosion troughs with characteristic U-notch in tangential sections is a characteristic feature of simultaneous rot that was apparent after 3 months of incubation. The decay pattern occurred concomitantly in all the xylem elements irrespective of general resistance pattern shown by vessel and axial parenchyma cells. At an advance stage, both species of Trametes showed formation of erosion channels along the microfibrils angle of cellulose which is considered as characteristics of soft rot decay type. The sharing of white rot and soft rot decay pattern by both the fungi suggest a phylogenetic link between both groups of fungi.  相似文献   

Adsorption of systemic pesticides on ground stems and in the apoplastic pathway of stems,as related to lignification and lipophilicity of the pesticides     

Eran Barak  Benjamin Jacoby  Amos Dinoor 《Pesticide biochemistry and physiology》1983,20(2):194-202

The adsorption of five systemic fungicides (carbendazim, triadimefon, nuarimol, triarimol, and fenarimol) and one herbicide (fluometuron) on ground stems and in the apoplastic pathway of excised pepper, cotton, and bean stems was studied. Adsorption on ground and water extracted stems, as well as retention in the apoplast of excised stems, increased with the 1-octanol/water partition coefficients of the pesticides. Methylation of ground stems increased their adsorption capacity (carbendazim excluded), while extraction with organic solvents did not affect it. Woody stems adsorbed more of the pesticides than herbaceous ones. Binding of pesticides in the apoplastic pathway of stems seems to be related to their degree of lignification and to the lipophilicity of the pesticides.  相似文献   

Glutathione synthesis in response to captan: A possible mechanism for resistance of Botrytis cinerea to the fungicide     

Eran Barak  Lloyd V. Edgington 《Pesticide biochemistry and physiology》1984,21(3):412-416

Two Botrytis cinerea isolates, field captan-resistant and normal type, were grown in liquid medium for 4 days prior to captan application. The glutathione (GSH) and oxidized glutathione (GSSG) of their mycelium and medium were analyzed at various times during the fifth day of their growth. Only slight differences in GSH levels between the isolates were observed, but marked differences in mycelial GSH were found in response to captan. Following the application of captan, less GSH was produced and after a longer lag period by the normal type of the fungus compared to the resistant isolate. This increase in the GSH level in the resistant isolate could make more nonvital thiol compound available for detoxifying captan and therefore prevent damage the fungicide could cause to the vital protein thiols of fungal cells.  相似文献   

苹果及其浓缩果汁中农药残留分析进展   总被引：2，自引：0，他引：2  

尚洁  乌日娜 《农药科学与管理》2007,28(12):9-12,20

本文综述了苹果及浓缩苹果汁中农药残留的提取和净化方法、检测技术及其研究新动向。  相似文献   

黄斑星天牛溴甲烷检疫熏蒸技术研究   总被引：2，自引：5，他引：2  

王跃进  詹国平  王新  徐亮  Alan Barak  吴颖  朱蕴智  杭小溪  戎子斌  黄庆林 《植物检疫》2003,17(1):1-6

对杨树木质包装溴甲烷熏蒸试验结果进行机率值法分析，推算出溴甲烷在4.4℃、10.0℃、15.5℃和21.1℃温度条件下达到黄斑星天牛（Anoplophora nobilis）幼虫死亡机率值9要求的CT值分别为：1133.78、938.21、642.39和349.87g.h/m^3；根据毒力试验结果进行的室内验证试验证明：在上述4个温度条件下，只要熏蒸中CT值达到了毒力测定的要求，就能够完全杀灭杨树携带的光肩星天牛（A.glabripennis）和黄斑星天牛幼虫、蛹，以及芳香木蠹蛾东方亚种（Cossus cossus orientalis）和杨干透翅蛾（Sphecia siningensis）幼虫。在此基础上，提出了木质包装溴甲烷检疫熏蒸处理的技术指标。  相似文献   

Abstracts of papers presented at a meeting of the phytopathological society of Israel on fungicides,their structure and activity     

Miriam Freund  P. Bracha  E. Barak  Y. Samoucha  Talma Katan  Y. Cohen  Y. Samoucha 《Phytoparasitica》1987,15(1):81-84

  相似文献   

蓖麻毒蛋白A链基因克隆与重复表达载体构建   总被引：1，自引：0，他引：1  

黄凤兰  李国瑞  萨日娜  陈永胜  阎秀峰 《中国油料作物学报》2009,31(2):167-172

利用降落PCR的方法,从蓖麻基因组DNA中克隆毒蛋白A链基因的560bp片段;利用一步法将该基因的2个正义片段和2个反义片段分别与pBI-121质粒连接,构建含该基因的正义重复和反义重复表达载体,为利用共抑制技术抑制蓖麻毒蛋白A链基因表达的研究奠定基础。  相似文献   

竹绿虎天牛溴甲烷熏蒸处理技术研究     

余道坚  焦懿  陈志粦  康林  杨伟东  陈枝楠  章桂明  詹国平  Alan V.Barak 《植物检疫》2009,23(3)

1985～2005年,美国报道从我国出口的竹制品中发现包括竹绿虎天牛(Chlorophorus annularis F.)在内的20多种有检疫意义的害虫.由于目前还没有针对竹制品中竹绿虎天牛的熏蒸处理技术指标,美国APHIS-PPQ采用其检疫处理手册的T404-d方案对竹制品进行熏蒸处理,即溴甲烷熏蒸24h.美国采用的竹制品熏蒸方案中溴甲烷的用量较高,本文应用比T404～d方案更低剂量的溴甲烷,研究竹桩中竹绿虎天牛的熏蒸效果.溴甲烷熏蒸试验在自制的小型熏蒸箱中进行,在26.7℃48 g/m3、21.1℃ 64 g/m3、15.6℃ 80 g/m3、10.0℃ 96 g/m3和4.4℃ 112 g/m3等5个温度和剂量组合,共20个试验(每个剂量4个重复)共熏蒸处理2847头幼虫、140头蛹和122头成虫,死亡率达100%,而在3组对照中共发现455头活虫.同时,用装满竹杆(80%)的20尺集装箱模拟竹制品出口熏蒸试验,以检查在24h的熏蒸过程中溴甲烷是否保持必需的浓度要求.本研究推荐了较低剂量的溴甲烷熏蒸处理竹制品的新的技术指标.  相似文献   

DYNAMIC STUDY OF PHOTOSYNTHETIC CHARACTERISTICS OF LANIX GMELINI     

SONG Cai-ling  ZHAO Peng-wu  SU Rina  HAI Long  ZHOU Mei  FENG Lin 《内蒙古农业大学学报(自然科学版)》2008,29(4)

  相似文献