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排序方式: 共有318条查询结果,搜索用时 15 毫秒
311.
Under field conditions in Germany over three growing seasons the pleiotropic effects on yield and its components of four sets of near isogenic lines carrying the GA insensitive dwarfing alleles Rht1, Rht2, Rht3, Rht1+2, Rht2+3 or rht (tall) in four different genetical backgrounds were examined together with 24 single chromosome recombinant lines segregating for the GA sensitive dwarfing gene Rht8 and the gene for day-length insensitivity Ppd1 in a ‘Cappelle-Desprez’ background. For the GA insensitive semi-dwarfs it was shown that in all three years a higher number of grains per ear was accompanied by a lower grain weight. Depending on the climatic conditions in a particular year, the increase in grain number was sufficient to compensate for the reduction in grain size and resulted in higher yields. For the Ppd1 allele yield advantages were found for wheats grown under environmental conditions of middle Europe. 相似文献
312.
Erika Hussar Sean Richards Zhi-Qing Lin Robert P. Dixon Kevin A. Johnson 《Water, air, and soil pollution》2012,223(9):5535-5548
South Chattanooga has been home to foundries, coke furnaces, chemical, wood preserving, tanning, and textile plants for over 100?years. Most of the industries were in place before any significant development of residential property in the area. During the 1950s and 1960s, however, the government purchased inexpensive property and constructed public housing projects in South Chattanooga. Many neighborhoods that surround the Chattanooga Creek were previous dumping grounds for industry. Polycyclic aromatic hydrocarbons (PAHs) comprised the largest component of the dumping and airborne industrial emissions. To address human exposure to these PAHs, a broad study of South Chattanooga soil contaminant concentrations was conducted on 20 sites across the city. Sixteen priority pollutant PAHs were quantified at two depths (0?C10 and 10?C20?cm) and compared against reference site soils, as well as to soils from industrially impacted areas in Germany, China, and the USA. From these data, the probability that people would encounter levels exceeding the United States Environmental Protection Agency (USEPA) residential preliminary remediation goals (PRG) was calculated. Results indicate that South Chattanooga soils have relatively high concentrations of total PAHs, specifically benzo[a]pyrene (B[a]P). These high concentrations of B[a]P were somewhat ubiquitous in South Chattanooga. Indeed, there is a high probability (88?%) of encountering soil in South Chattanooga that exceeds the USEPA PRG for B[a]P. However, there is a low probability (15?%) of encountering a site with ??PAHs exceeding USEPA PRG guidelines. 相似文献
313.
Eckerter Philipp W. Albrecht Matthias Bertrand Colette Gobet Erika Herzog Felix Pfister Sonja C. Tinner Willy Entling Martin H. 《Landscape Ecology》2022,37(6):1573-1586
Landscape Ecology - Flowering plants can enhance wild insect populations and their pollination services to crops in agricultural landscapes, especially when they flower before the focal crop.... 相似文献
314.
Shaw MR Zavaleta ES Chiariello NR Cleland EE Mooney HA Field CB 《Science (New York, N.Y.)》2002,298(5600):1987-1990
Simulated global changes, including warming, increased precipitation, and nitrogen deposition, alone and in concert, increased net primary production (NPP) in the third year of ecosystem-scale manipulations in a California annual grassland. Elevated carbon dioxide also increased NPP, but only as a single-factor treatment. Across all multifactor manipulations, elevated carbon dioxide suppressed root allocation, decreasing the positive effects of increased temperature, precipitation, and nitrogen deposition on NPP. The NPP responses to interacting global changes differed greatly from simple combinations of single-factor responses. These findings indicate the importance of a multifactor experimental approach to understanding ecosystem responses to global change. 相似文献
315.
Debasis MITRA Sergio DE LOS SANTOS-VILLALOBOS Fannie Isela PARRA-COTA Ana Mara Garcia MONTELONGO Erika Lorena BLANCO Vanessa L. LIRA Adeyemi N. OLATUNBOSUN Bahman KHOSHRU Rittick MONDAL Parameswaran CHIDAMBARANATHAN Periyasamy PANNEERSELVAM Pradeep K. DAS MOHAPATRA 《土壤圈》2023,33(2):268-286
Various microorganisms live in association with different parts of plants and can be harmful, neutral, or beneficial to plant health. Some microbial inhabitants of plants can control plant diseases by contesting with, predating on, or antagonizing plant pathogens and by inducing systems for plant defense. A range of methods, including plant growth-promoting microorganisms(PGPMs) as biological control agents(BCAs)(BCA-PGPMs) are used for the biological management and control of plant pathogens. S... 相似文献
316.
317.
Agricultural insect pests display an exceptional ability to adapt quickly to natural and anthropogenic stressors. Emerging evidence suggests that frequent and varied sources of stress play an important role in driving protective physiological responses; therefore, intensively managed agroecosystems combined with climatic shifts might be an ideal crucible for stress adaptation. Cross-protection, where responses to one stressor offers protection against another type of stressor, has been well documented in many insect species, yet the molecular and epigenetic underpinnings that drive overlapping protective responses in insect pests remain unclear. In this perspective, we discuss cross-protection mechanisms and provide an argument for its potential role in increasing tolerance to a wide range of natural and anthropogenic stressors in agricultural insect pests. By drawing from existing literature on single and multiple stressor studies, we outline the processes that facilitate cross-protective interactions, including epigenetic modifications, which are understudied in insect stress responses. Finally, we discuss the implications of cross-protection for insect pest management, focusing on the consequences of cross-protection between insecticides and elevated temperatures associated with climate change. Given the multiple ways that insect pests are intensively managed in agroecosystems, we suggest that examining the role of multiple stressors can be important in understanding the wide adaptability of agricultural insect pests. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
318.
Siwaporn Siltecho Nopmanee Suvannang Juthamard Kaiphoem Erika Medeiros José Romualdo de Sousa Lima Nattaporn Prakongkep Robert Gilkes Claude Hammecker 《Soil Use and Management》2022,38(2):1293-1306
Pradoo wood biochar has been tested in order to explore sustainable solutions to the development of agriculture on poor sandy soils in marginal areas in Northeast Thailand. Some basic physicochemical properties of biochar, for example pore size distribution, cation exchange capacity (CEC), specific surface area (SSA), and water and nutrient adsorption, were determined and compared to soil properties in order to determine appropriate biochar application to soil. Pradoo wood biochar showed important adsorption properties with high SSA, CEC and nutrient adsorption. The water retention properties were also improved on the dry end of the water retention curve. Phosphorous and ammonium adsorption–desorption isotherms were established and their respective affinity for the biochar surface was quantified, by the means of a retention index and thermodynamical parameters. We found that despite excellent retention properties, biochar needs to be added in large amounts (between 10 and 70 kg m−2) to soil to be able to modify noticeably the resulting soil properties. 相似文献