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71.
生长素在烤烟库源关系改变时对烟株根系钾的影响 总被引:2,自引:0,他引:2
采用土培试验方法,研究内外源生长素在不同生长阶段缺钾或供钾条件下对烟株根系钾的影响。结果表明:缺钾胁迫下,外源生长素在不同地烟株根系积累钾有很大的促进作用,内源生长素在腰叶成熟前对烟株根系积累钾的能力有一定的稳定作用。供钾条件下,内外源生长素在不同生长阶段对烟株根系积累钾均有很大的促进作用,其促进作用比缺钾胁迫时大。且无论缺钾与否,外源生长素对烟株根系积累钾的促进作用大于内源生长素的作用。 相似文献
72.
关中地区烤烟良种(系)适应性研究 总被引:2,自引:2,他引:0
以NC89(CK1)、秦烟96(CK2)为对照,对12个烤烟新品种(系)进行了小区比较试验,结果表明:Y8342、中烟202、9407、兴烟1号等4个品种具有较大的发展潜力。 相似文献
73.
为探索适宜烤烟生长的前茬作物,完善烤烟的种植制度,以烤烟连作为对照,研究了玉米(T1)、豆类/蔬菜(T2)和土豆(T3)三种前茬作物对烤烟成熟期农艺性状、根系发育、生物量和土壤养分含量的影响。结果表明,所有农艺性状指标中数值最高的是均为T2 处理,根深度和水平根宽度由高到低的处理顺序为T2>T3>T1>CK,根、茎、叶干物质重从高到低的处理顺序也为T2>T3>T1>CK;土壤养分中pH值、有机质含量、碱解氮含量从高到低的处理顺序为T2>T1>T3>CK。综上,适宜烤烟生长的前茬作物为豆类/蔬菜,其次为土豆。 相似文献
74.
Yoshikazu Kiriiwa Sunao Osumi Masanobu Endo Akira Nukaya Akio Morita Hiromi Yokota 《Soil Science and Plant Nutrition》2013,59(7):1119-1124
Abstract In alkaline soils, plant growth is impaired mainly by high pH and high concentration of bicarbonates. The bicarbonate concentration increases the pH value, and causes deficiency of iron. A bicarbonate-resistant cell line (BR line) of tobacco (Nicotiana tabacum L. cv. Burley21) was selected by adding excess bicarbonate ions (20 mmol L?1) to the culture medium. The pH of the medium was buffered 8.0 to 8.3. Under these conditions, about 80% of iron in the medium became insoluble. However, under such conditions, the BR line grew well. In this report, we examined some characteristics of the growth and iron uptake in the BR line under iron-deficient (i.e. high pH or no-iron) condition. At pH 5.8, the Fe3+ reduction activity was not significantly different between the non-selected line and the BR line. At pH 8.0, however, the Fe3+ reduction activity of the BR line was higher than that of the non-selected line. In no-iron condition, the growth of the non-selected line was markedly reduced after 2 weeks, while the BR line was not affected. The content of malic acid in both lines increased with the medium pH, and the content in the BR line was higher than that in the non-selected line. The BR line was able to adapt to the conditions, which restricted iron uptake, such as high bicarbonate concentration, high pH, and low iron conditions. The high ability of Fe3+ reduction was maintained at even high pH conditions. Further, the BR line may be able to improve the utilization of iron in the cells. 相似文献
75.
76.
利用保健栽培技术防治烟草黑胫病的研究 总被引:3,自引:1,他引:2
进行利用保健栽培防治烟草黑胫病的试验研究,结果表明:膜下小苗移栽的各项指标均优于其他处理,其防效达84.00%,烟叶鲜干比为7.00,上中等烟比例为90.76%,产量为2 382.00 kg/hm2。 相似文献
77.
以威灵仙根部为原料,采用黄酒用量、干燥条件、提取时间三因素,三水平的L9(34)正交试验设计,以水煎物干膏提取率、薄层层析检测威灵仙中的三萜皂苷为主要考核指标。结果表明:黄酒用量对威灵仙总皂苷提取率有极显著影响,烘干条件有显著影响,提取时间对试验结果影响不显著,表明影响因素最大的是黄酒用量,其次是干燥条件。 相似文献
78.
79.
Xanthomonas axonopodis pv. glycines ( Xag ) causes bacterial pustule disease which can significantly reduce the production of soybean. A collection of 26 isolates of Xag from different soybean-production areas of Thailand was shown to differ with regard to aggressiveness on soybean. They also differed in their ability to induce a hypersensitive response (HR) on four cultivars of tobacco and on other plant species including pepper, tomato, cucumber, pea and sesame. Tomato was most sensitive to HR induction by Xag . Isolate KU-P-34017 caused an HR on all the plant species tested. The minimal concentration of KU-P-34017 needed to induce HR on tobacco was approximately 5 × 108 CFU mL−1 . A bacterium–plant interaction period of at least 2·5 h was necessary for HR, and different temperatures, relative humidity and light periods did not affect HR development. Inhibitors of eukaryotic metabolism, including cobalt chloride, lanthanum chloride and sodium orthovanadate (completely), and cycloheximide (partially) blocked the HR on tobacco, indicating the association of an active plant response. In contrast, the HR on tomato was inhibited only by cobalt chloride. 相似文献
80.
Inducible responses in plants against pathogen attack play a major role in resistance to disease. The defense responses are
mostly associated with the expression of various kinds of inducible genes. We employed differential hybridization to isolate
elicitor-inducible genes (EIGs) of tobacco (Nicotiana tabacum cv. Samsun NN) using the tobacco-fungal elicitor system. A cDNA library was constructed from tobacco leaves treated for 12
hr with hyphal wall components (HWC) prepared from Phytophthora infestans, and six EIGs were identified. Expression of all EIGs was induced after inoculation with the soybean pathogen Pseudomonas syringae pv. glycinea (nonpathogenic on tobacco) or treatment with salicylic acid, and a variety of expression patterns of EIG mRNAs was observed.
Sequence analysis of EIG cDNAs revealed similarities to genes for SAR8.2 (EIG-B39 and EIG-D14), glycine-rich protein (EIG-G7), extensin (EIG-I30), acyltransferase (EIG-I24) and unknown protein (EIG-J7). Possible roles of EIG products in disease resistance are discussed.
Received 30 August 2000/ Accepted in revised form 30 November 2000 相似文献