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Somatic Embryogenesis in Iberian Grapevine (Vitis vinifera) Cultivars Using Carpels as Initial Explants: Protocol Establishment and Histological Evaluation 被引量:2
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作者 Hélia Guerra Cardoso Maria Catarina Campos +1 位作者 Maria Salomé Pais Augusto Peixe 《Journal of Agricultural Science and Technology(B)》 2019年第1期15-30,共16页
Trincadeira and Aragonez are two important grapevine cultivars in the Iberian Peninsula, used for high quality red wines production. Both cultivars are strongly affected by fungal diseases, with consequent high loses ... Trincadeira and Aragonez are two important grapevine cultivars in the Iberian Peninsula, used for high quality red wines production. Both cultivars are strongly affected by fungal diseases, with consequent high loses on plant productivity and fruit quality. A successful protocol for plant regeneration via somatic embryogenesis (SE) was established for both cultivars allowing further plant improvement based on gene transfer technology. Several factors were evaluated during the three different phases which characterize an SE plant regeneration protocol. The culture room temperature during the induction phase, a parameter usually accepted as standard by most researchers, proved in these trials to significantly affect the embryo induction rates. Concerning embryo conversion, it was specially affected by the embryo developmental stage, by the intensity and duration of the chilling treatment and by the supplementation of conversion culture medium with activated charcoal. The responses obtained, both for induction and conversion, proved to be highly genotype dependent. Calli structure, as well as embryo integrity, was histologically observed, allowing to characterize embryonic and non-embryonic masses and to identify abnormalities on embryo development. 展开更多
关键词 Aragonez Trincadeira GRAPEVINE MEGASPOROGENESIS somatic EMBRYOGENESIS
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Development of a Data Acquisition System to Optimizing the Agricultural Tractor Performance 被引量:1
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作者 J. M. Serrano J. O. Peca +3 位作者 S. Shahidian M. C. Nunes L. Ribeiro F. Santos 《Journal of Agricultural Science and Technology(B)》 2011年第5期756-766,共11页
A novel data acquisition system was successfully integrated on-board the Massey Ferguson 3,000 series agricultural tractors for measuring tractor-implement performance. A commercial load cell was incorporated into the... A novel data acquisition system was successfully integrated on-board the Massey Ferguson 3,000 series agricultural tractors for measuring tractor-implement performance. A commercial load cell was incorporated into the existing system for the needed tractor-implement performance, measurements. This system is capable of measuring, displaying and recording, in real-time, the tractor's theoretical travel speed, the actual travel speed, the engine speed, the fuel consumption rate, and the drawbar pull. Static calibration tests on various associated sensors for the required measurements show excellent linearity with correlation coefficients that are close to 1. The developed system was extensively and successfully field demonstrated for tractor-implement performance with offset disc harrows on dry, undisturbed loamy soils. Under these conditions, a ratio of tractor power to implement width is suggested. The data also show the existence of a linear relationship between fuel consumption per hectare and specific draught, for the 4 to 9 kN m^-1 range, which suggests the possibility of extending the American Society of Agricultural and Biological Engineers model of draught prediction to forecast fuel consumption. The configuration of the tractor-harrow combination, based on the measurement of the draught required under operational conditions, provides the manufacturers with a reliable indication of the recommended power required for each harrow model. With this type of information farmers can make decisions regarding selection of a suitable tractor-implement combination for their farms. As a consequence, there is improved tractor-harrow productivity and field efficiency. 展开更多
关键词 Data acquisition system datatronic TILLAGE tractor implement performance
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Evaluation of Variable Rate Technology for Fertilizer Application in Permanent Pastures
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作者 J. M. Serrano J. M. Peca Shahidian 《Journal of Agricultural Science and Technology(A)》 2011年第4X期489-499,共11页
This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a signifi... This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a significant and systematic difference between the application rates of the two discs (about 20%). This difference had to be corrected by the manufacturer that carried out the necessary changes to the electric actuators. The fertilizer spreader had good distribution homogeneity, considering different working velocities and different positions in the parcel. The pattern distribution curve for 18% super phosphate fertilizer led to an effective working width of 28 meters, with a coefficient of variation of 15%. The longitudinal test, under experimental working conditions led to a machine delay time of 6-7 seconds. The results show an actual fertilization application density between 74%-90% of that determined for each location. These results confirm that the spreader can be used to spread fertilizer differentially in the field. 展开更多
关键词 Calibration centrifugal fertilizer spreader evaluation precision agriculture variable rate technology.
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Comparative Analysis of Energy Efficiency in Wheat Production in Different Climate Conditions of Europe
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作者 Janusz Gotaszewski Marcel van der Voort +3 位作者 Andreas Meyer-Aurich Fatima Baptista Athanasios Balafoutis Hannu Juhani Mikkola 《Journal of Agricultural Science and Technology(B)》 2014年第8期632-640,共9页
This paper presents results concerning energy efficiency of wheat production considered in the context of specific energy input variation in different climatic conditions of Europe as well as case studies on implement... This paper presents results concerning energy efficiency of wheat production considered in the context of specific energy input variation in different climatic conditions of Europe as well as case studies on implementation of selected energy saving measures in practice. The source data collected from the six european union (EU) countries represent five agricultural regions of continental Europe and three climates: continental, temperate and Mediterranean. The life cycle assessment (LCA) methodology was applied to analyze the data excluding of pre-farm gate activities. The total primary energy consumption was decomposed into main energy input streams and it was regressed to yield. In order to compare energy efficiency of wheat production across the geographical areas, the data envelopment analysis (DEA) was applied. It was shown that the highest wheat yield (6.7 t/ha to 8.7 t/ha) at the lowest specific energy input (2.08 GJ/t to 2.56 G J/t) is unique for temperate climate conditions. The yield in continental and Mediterranean climatic conditions is on average lower by 1.3 t/ha and 2.7 t/ha and energy efficiency lower by 14% and 38%, respectively. The case studies have shown that the energy saving activities in wheat production may be universal for the climatic zones or specific for a given geographical location. It was stated that trade-offs between energy, economic, and environmental effects, which are associated with implementation of a given energy saving measure or a set of measures to a great extent depend on the current energy efficiency status of the farm and opportunity for investment, which varies substantially across Europe. 展开更多
关键词 WHEAT energy efficiency trade-off analysis
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Soil and Phytosociological Characterisation of Grasslands in the Western Mediterranean
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作者 A. Cano-Ortiz E. Bioindi +2 位作者 C. J. Pinto Gomes S. Del Río González E. Cano 《American Journal of Plant Sciences》 2014年第21期3213-3240,共28页
A study was made of grasslands in olive groves with a high frequency of Hordeum leporinum Link, Chrysanthemum coronarium L., Malva neglecta Wallr., Aegilops geniculata Roth and Dasypyrum villosum (L.) Borbas, initiall... A study was made of grasslands in olive groves with a high frequency of Hordeum leporinum Link, Chrysanthemum coronarium L., Malva neglecta Wallr., Aegilops geniculata Roth and Dasypyrum villosum (L.) Borbas, initially included in the alliance Hordeion leporini Br.-Bl. in Br.-Bl., Gajewski, Wraber & Walas 1936 corr. O. Bolós 1962, and sub-alliance Malvenion neglectae Gutte 1966. The study was carried out in the western Mediterranean (Spain, Italy, Portugal and northern Morocco). The soil and phytosociological treatment of the samples contributes information for new plant communities. In the study of plant communities, the indices of degree of presence are adapted to those of Van der Maarel. The new alliance Securigero securidacae-Dasypyrion villosi is proposed for the sub-Mediterranean and Euro-Siberian territories, with the new communities Securigero securidacae-Dasypyretum villosi and Convolvulo elegantissimi-Aegilopetum geniculatae. This last community, due to its richness in Aegilops geniculata Roth, could be included in the alliance Taeniathero-Aegilopion geniculatae Rivas-Martínez & Izco 1977;however, the soil and statistical analyses reveal that it should remain part of the alliance Securigero securidacae-Dasypyrion villosi. The soil and floristic study of Hordeion leporini and Malvenion neglectae allows us to describe the new sub-alliance Resedo albae-Chrysanthemenion coronarii, subordinated to Malvion neglectae (Gutte 1966) status novo. 展开更多
关键词 SOIL GRASSLAND COMMUNITY ASSOCIATION
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