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991.
D. Zhu T. W. Wang C. F. Cai L. Li Z. H. Shi 《Land Degradation \u0026amp; Development》2009,20(6):654-666
Reliable and cost‐effective soil erosion assessment is an important precondition for soil conservation measures, which remains a major challenge at large scale. Considering that the neuro‐fuzzy model has the special advantage in multi‐index comprehensive assessment and GIS technology is adept at geo‐spatial information processing, through the combination of them, it is possible to provide an effective approach for this difficult problem. Taking Hubei Province as a case study area, five evaluating indicators were selected for the large‐scale assessment, in which the GIS technology was used to construct the classification maps of evaluating indicators and to divide basic assessment units, and the neuro‐fuzzy model was adopted to extract fuzzy rules for individual units assessment from available ground truth data. According to the optimized assessment criteria generated by the neuro‐fuzzy model, the soil erosion state of the entire study area was then assessed. To represent the spatial distribution of soil erosion, a detailed map was produced by statistical mapping, which was represented with six erosion levels (from slight to severe) at a map scale of 1:250 000. The resulting map showed that about 30.1% of the total land area in Hubei was affected by different levels of soil erosion problem. Western high mountains and eastern low mountains suffered from the most serious erosion damage, a strong level of soil erosion was widely observed in these mountains. Large areas of moderate level erosion occurred in the northern hills. In contrast, most of the central plains were characterized as slight level erosion effect. The validation indicated that an overall accuracy of 88% and a κ of 0.89 were achieved, proving that the resulting map was in conformity with actual conditions, which indicates this assessment approach was reasonable and applicable. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
992.
993.
Journal of Plant Diseases and Protection - Root-knot nematodes (Meloidogyne spp.) are among the most damaging soilborne plant parasites and are responsible for large economic losses in a wide... 相似文献
994.
Plant glutathione S‐transferase (GST) forms a major part of the herbicide detoxification enzyme network in plants. A GST cDNA was isolated from Echinochloa crus‐galli and characterised. The gene, designated EcGST1 (E. crus‐galli GeneBank no: JX518596 ), has a 684 bp open reading frame predicted to encode a 25 kD protein. Sequence alignment showed that EcGST1 is a GST homologue. Its expression in response to quinclorac treatment was monitored in seedlings (leaves and roots) and adult plants (leaves, roots, stems and seeds) of quinclorac‐resistant (R) and susceptible (S) biotypes of E. crus‐galli. EcGST1 expression was 1.5–3 times greater in the R plants than in the S plants. However, after exposure to quinclorac, the difference in the expression levels of EcGST1 in R plants, compared with S plants, increased to a ratio of 6–10. Enhanced EcGST1 levels should enable greater quinclorac detoxification following quinclorac stimulation in R plants. GST‐based metabolism may be partially responsible for resistance to quinclorac in E. crus‐galli. The results suggest a new resistance mechanism for this R biotype in Chinese rice fields. 相似文献
995.
对采自贵州盘县八大山地区的1000余号苔藓植物标本进行了整理和鉴定。结果表明:该地区有苔藓植物54科125属277种(包括亚种、变种),其中,优势科:有丛藓科Pottiaceae、青藓科Brachytheciaceae、灰藓科Hypnaceae、羽苔科Plagiochilacea和地萼苔科Geocalyaceae等;优势属有青藓属Brachythecium、淘灯藓属Plagiomnium和真藓属Bryum等。 相似文献
996.
为了研究水稻Os09g29390基因在冷胁迫条件下的功能,以水稻苗期冷胁迫基因表达谱芯片中编码水稻质体蓝素类蛋白(Plastocyanin like protein)的下调表达基因Os09g29390为研究对象,对Os09g29390基因进行冷胁迫下表达特性分析、同源性分析及亚细胞定位分析.结果表明,Os09g29390基因在冷胁迫处理下表现为下调表达模式;氨基酸相似性分析与保守结构域分析显示,Os09g29390基因与其同源基因的氨基酸编码序列具有一个保守的铜结合位点;将Os09g29390基因与增强型绿色荧光蛋白(eGFP)融合,转化烟草原生质体,结果Os09g29390基因定位于细胞叶绿体中.以上结果初步阐明该基因在冷胁迫下的表达特性及作用位点,为以后更深入的研究该基因的功能提供了指导. 相似文献
997.
加强林农实用技术培训对于加快社会主义新农村建设,实现生态林业、民生林业的战略目标,全面建成小康社会具有重要意义.面对培训对象需求的多样性、特殊性以及时间的有限性等,要科学合理地制定林农实用技术培训方案,编写适合林农需求的培训教材,合理评聘和培养培训教师,改进教学方式方法,加强培训教学质量的监督与评估,以保证林农实用技术培训教学的质量,提高培训效果. 相似文献
998.
999.
S. Ke Q. Cai R. M. Skirvin 《The Journal of Horticultural Science and Biotechnology》2013,88(6):837-840
Protoplast-derived shoots (protoclones) of kiwifruit (Actinidia deliciosa) were cleft grafted directly from in vitro conditions onto mature rootstocks under field conditions on several different dates from June to August in 1987 and 1988. Shoots were taken from culture vessels, prepared for a cleft graft, placed in a cleft on a rootstock, covered with a glass culture tube and sealed with cotton fibres. Other plants were self-rooted in vitro and planted in the field to compare the growth rates and maturity rates of the two plant types. 相似文献
1000.
奇楠沉香为极具收藏及药用价值的上品沉香,其鉴定目前以化学方法为主,但其种苗从苗期至采香之间则难以用传统分类和化学方法进行鉴定,DNA条形码的发展为这一产业难题的解决提供了新的思路。本研究在明确白木香良种‘热科2号’可产奇楠沉香的基础上,采用11对植物DNA条形码通用引物对‘热科2号’和普通白木香两个沉香品种进行分子鉴定探索,发现改良的CTAB法更适合白木香叶片样本的DNA提取,继而发现ITS、ITS2和源自叶绿体的8个DNA条形码在两个品种均无变异,而ITS1序列的第159个碱基在‘热科2号’中为T,在普通白木香中为A,多样本实验证明该变异位点可以作为‘热科2号’和普通白木香种苗鉴定的分子标记。本研究结果为白木香良种‘热科2号’及其幼苗的鉴定提供分子水平的技术支持,也为白木香良种的溯源提供新的思路。 相似文献