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981.
Alberto C. De Campos Bernardi Quirino A. De Camargo Carmello Sérgio Alves De Carvalho Eduardo Caruso Machado Camilo Lázaro Medina Mara De Menezes De Assis Gomes 《Journal of plant nutrition》2015,38(12):1902-1912
The objective of this research was to evaluate the nitrogen, phosphorus and potassium (NPK) fertilizer effect on the development of ‘Valencia’ sweet orange nursery trees budded on Rangpur lime rootstocks in a greenhouse using containers. The experiment was a complete (1/5) 53 factorial randomized blocks design. Treatments comprised five concentrations (g per plant) of N (1.25; 6.25; 11.25; 16.25; 21.25); K (0.42; 3.75; 6.22; 9.34; 12.45); and P (0.19; 0.89; 1.59; 2.29; 2.99). Carbon dioxide assimilation rate (A), transpiration rate (E), stomata conductance (gs), and internal carbon dioxide (CO2) concentration (Ci) and water use efficiency (WUE). Reducing sugar, sucrose and starch were evaluated. Response functions were adjusted and nutrient rates for maximum yield were presented. The results indicated that the high levels of N (>16.25 g per plant) interferes negatively on photosynthesis. Potassium at intermediate fertilization levels (from 3.75 to 6.22 g per plant) had positive effects on photosynthesis. But P had little interference on photosynthesis. Carbohydrates levels were not related to nutrients fertilized. 相似文献
982.
Samuel Munyaka Kimani Putu Oki Bimantara Satoshi Hattori Keitaro Tawaraya Shigeto Sudo 《Soil Science and Plant Nutrition》2020,66(1):152-162
ABSTRACT To investigate the influence of Azolla (A. filiculoides Lam.) incorporated as a green manure and its subsequent growth as a dual crop with rice on simultaneous methane (CH4) and nitrous oxide (N2O) emissions from a flooded alluvial soil planted with rice, a pot experiment with three treatments, chemical fertilizers (NPK) as the control, incorporation of Azolla as green manure (AGM), and AGM plus basal chemical fertilizers (NPK+AGM) was conducted in Tsuruoka, Yamagata, Japan in 2017. AGM and NPK+AGM treatments significantly increased CH4 emissions at early rice growth stages before 63 days after transplanting (DAT) by 123.0% and 176.7% compared to NPK, respectively. At late rice growth stages (after 63 DAT), only the NPK+AGM treatment significantly increased CH4 emission by 22.1% compared to NPK. However, percentage of CH4 emitted after 63 DAT relative to the seasonal CH4 emission followed the order of NPK (86.2%) > AGM (76.5%) > NPK+AGM (73.3%). Higher CH4 emissions from AGM and NPK+AGM before 63 DAT were attributed to the incorporated Azolla, while the higher emissions after 63 DAT in all treatment groups were ascribed to rice photosynthesis. AGM and NPK+AGM treatments significantly decreased N2O emissions by 71.6% and 81.1% compared to NPK, respectively, at early rice growth stages. Azolla incorporation may have restricted N2O emission from initial soil nitrate before 63 DAT and not have contributed to N2O emissions after 63 DAT. Significantly higher grain yields were observed under the AGM (32.5%) and NPK+AGM (36.3%) compared to NPK. Together, AGM and NPK+AGM treatments significantly increased seasonal CH4 emissions by 31.5% and 43.5%, and decreased seasonal N2O emissions 3.4- and 4.6- fold compared to NPK, respectively. There were no significant differences in the CH4 emissions per grain yield among the treatments; however compared to NPK, AGM and NPK+AGM treatments significantly reduced N2O emissions per grain yield by 78.7% and 84.1%, respectively. 相似文献
983.
Bruno Baur Samuel ZschokkeArmin Coray Martin SchläpferAndreas Erhardt 《Biological conservation》2002,105(2):133-142
Habitat destruction and degradation are the major causes for the decline of the endangered grass-feeding flightless beetle Dorcadion fuliginator in Central Europe. We examined habitat characteristics at 19 localities which still support abundant D. fuliginator populations in the southern part of the Upper Rhine valley (border region of Switzerland, Germany and France) to obtain basic information for the management of deteriorating habitats with declining beetle populations. Populations of D. fuliginator were found in different types of grassland on south, south-west and south-east facing slopes and flat ground. Correspondence analysis showed that plant communities of D. fuliginator localities overlap widely with fertilized, dry hay meadows (phyto-sociologically defined as dry type of the Arrhenatheretum community) and to a minor extent with traditionally extensively cultivated dry grasslands (Xerobrometum and Teucrio-Mesobrometum communities). Average indicator scores of the plant communities characterize the habitat of D. fuliginator as fairly light-exposed and warm, but with relatively large ranges in humidity and nutrient content. The results of a 16-year study on the timing of emergence of the first beetles in a population provided further evidence for the high temperature requirements of D. fuliginator. Proposed conservation measures include traditional cultivation of the present secondary, man-made D. fuliginator habitats, introduction of beetles to suitable motorway embankments as well as large-scale measures allowing natural dynamics in the flood plain along the river Rhine, the presumably primordial habitat of this highly endangered beetle. 相似文献
984.
Hold GL Russell VJ Pryde SE Rehbein H Quinteiro J Vidal R Rey-Mendez M Sotelo CG Pérez-Martin RI Santos AT Rosa C 《Journal of agricultural and food chemistry》2001,49(3):1175-1179
Analysis of restriction fragment length polymorphism (RFLP) profiles of a 464 bp amplicon obtained from the mitochondrial cytochrome b gene was used to differentiate between several different fish species. The method was tested by a collaborative study in which 12 European laboratories participated to ascertain whether the method was reproducible. Each laboratory was required to identify 10 unknown samples by comparison with RFLP profiles from authentic species. From a total of 120 tests performed, unknown samples were correctly identified in 96% of cases. Further work attempting to use the method to analyze mixed and processed fish samples was also performed. In all cases the species contained within mixed samples were correctly identified, indicating the efficacy of the method for detecting fraudulent substitution of fish species in food products. 相似文献
985.
V. Sérgio Emílio Dos Santos M. Aparecido Gimenes J. Francisco Montenegro Valls C. Romero Lopes 《Genetic Resources and Crop Evolution》2003,50(8):841-848
Some Arachis species are widely used as commercial plants, e.g. the groundnut A. hypogaea, an important source of good quality protein and oil, and A. pintoi and A. glabrata, that are utilized as forage species. Germplasm of most Arachis species is available in germplasm banks. However, little it is known about the genetic attributes of this germplasm, and mainly about its genetic variability, which is very important for its maintenance. In the present study RAPDs were used to assay the genetic variation within and among 48 accessions of five sections of the genus Arachis and to establish the genetic relationships among these accessions. Ten of 34 primers tested were selected for DNA amplification reactions since they yielded the largest numbers of polymorphic loci. A dendrogram was constructed based on data from the 10 primers selected. Eighty RAPD polymorphic bands were analyzed among the accessions studied. The relationships among species based on RAPDs were similar to those previously reported based on morphological, cytological and crossability data; demonstrating that RAPDs can be used to determine the genetic relationships among species of the different sections of the genus Arachis. In general, wide variation was found among accessions and low variation was found within the accessions that had two or more plants analyzed. However, higher polymorphism was found in the section Trierectoides and in one accession of A. major, indicating that generalizations should be avoided and each species should be analyzed in order to establish collection and maintenance strategies. 相似文献
986.
dos Santos Araújo Fernando Arriel Nair Helena Castro de Medeiros Everaldo Paulo de Lima Liziane Maria de Souza Mayara Andrade de Andrade Alberício Pereira de Lucena Alcântara Bruno Riselane 《Genetic Resources and Crop Evolution》2022,69(3):1219-1227
Genetic Resources and Crop Evolution - The remaining populations of perennial cotton (Gossypium hirsutum L. r. marie-galante Hutch.) that occur in northeastern Brazil are part of the primary gene... 相似文献
987.
de Souza Carneiro Adriana dos Santos Adriano Laviola Bruno Galvas Teodoro Larissa Pereira Ribeiro Teodoro Paulo Eduardo Rodrigues Erina Vitrio 《Genetic Resources and Crop Evolution》2022,69(1):245-254
Genetic Resources and Crop Evolution - Jatropha (Jatropha curcas L.) is an oleaginous potential, howetever, some studies report that there is low genetic diversity in Brazilian genotypes.... 相似文献
988.
Craighead Kimberly Yacelga Milton Wan Ho Yi Vogt Robert Cushman Samuel A. 《Landscape Ecology》2022,37(1):129-146
Landscape Ecology - Few habitat modeling studies consider multiple spatial or temporal scales; less identify the operative scale of an organism's response to predictor variables. Optimizing... 相似文献
989.
Stupariu Mihai-Sorin Cushman Samuel A. Pleşoianu Alin-Ionuţ Pătru-Stupariu Ileana Fürst Christine 《Landscape Ecology》2022,37(5):1227-1250
Landscape Ecology - Artificial Intelligence (AI) has rapidly developed over the past several decades. Several related AI approaches, such as Machine Learning (ML), have been applied to research on... 相似文献
990.
Silveira dos Santos Juliana Vitorino Luciana Cristina Fabrega Gonçalves Renata Corrêa Côrtes Marina Souza Cruz Alves Rafael Cezar Ribeiro Milton Garcia Collevatti Rosane 《Landscape Ecology》2022,37(10):2481-2501
Landscape Ecology - Despite the importance of secondary forests for the maintenance of biodiversity, the impact of pioneer trees on habitat loss and fragmentation is poorly understood. We analyzed... 相似文献