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111.
Solis-Badillo Elizabeth Agama-Acevedo Edith Tiessen Axel Lopez Valenzuela Jose A. Bello-Perez Luis A. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):76-82
Plant Foods for Human Nutrition - ADP-glucose pyrophosphorylase (AGPase) is a key enzyme of starch synthesis in seeds, tubers and fruits. UDP-glucose pyrophosphorylase (UGPase) is an important... 相似文献
112.
Blanch Gracia Patricia Gómez-Jiménez Maria C. del Castillo Maria Luisa Ruiz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):177-183
Plant Foods for Human Nutrition - Grapes contain high contents of phenolics, which are known to possess health promoting properties. Exogenous application of phytoregulators, mainly methyl... 相似文献
113.
A study was conducted in northwest Florida, USA, to investigate root development and morphology of cotton (Gossypium hirsutum L.) under pecan (Carya illinoensis K. Koch) trees in an alleycropping experiment. Root:shoot ratio, root biomass, total root length and root length density
were examined under three treatments: (1) barrier (separating belowground interspecific competition by trenching to a depth
of 120 cm and installing polyethylene barrier), (2) non-barrier (root systems were free to interact), and (3) monoculture
of cotton (without above and belowground interspecific competition with trees). Results indicated that plants in the barrier
and non-barrier treatments had lower root:shoot ratios compared to the monoculture treatment. Belowground competition for
resources between pecan and cotton in the non-barrier treatment resulted in 25 and 33% reduction of total root length (359 cm)
when compared to that of the barrier (477 cm) and monoculture (539 cm) treatments, respectively. The non-barrier plants also
exhibited the lowest root length density. Specific root length was highest for the monoculture (179 cm g−1) and lowest for the non-barrier treatment (146 cm g−1) with the barrier treatment being intermediate (165 cm g−1). Interspecific competition with pecan significantly altered root development and morphology of cotton plants. Research in
agroforestry should take into account the developmental differences in root systems of the associated crop species so that
better models incorporating nutrient and water uptake can be developed. 相似文献
114.
In this paper, we report molecular investigation of an ectomycorrhizal fungi (EMF) community of European larch (Larix decidua Mill.) seedlings grown in a bare-root nursery. In total, we surveyed 32 nurseries that were each active in supplying planting stocks to restock forests and for afforestation of post-agricultural land. Sequence-based approach was used to identify EMF taxa, quantify EMF richness, and document differences in the relative abundance of individual taxa. We identified seven fungal species that might contribute to the mycorrhizal community structure of 1 to 3-year-old L. decidua seedlings. The species richness in the examined larches varied between one and four fungal taxa, depending on both the nursery stock samples (NSS) and age class of the seedlings. The average was 1.4 for 1-year-old seedlings and 2.3 for 2- and 3-year-old plants. The dominance of Ascomycota over Basidiomycota and the prevalence of two species, Wilcoxina mikolae and Suillus grevillei, as EMF partners were characteristic features of nursery-grown L. decidua seedlings. S. grevillei was the only one basidiomycetes colonized roots of tested seedlings. The rest of the mycorrhizal pool from forest nurseries was typically dominated by pioneer fungal ascomycetes. W. mikolae was the most common mycorrhizal ascomycete present at a high frequency on NSS from both age classes and with very high abundance (average 90%) on 1-year-old seedlings. Some other ascomycetes (Pezizales 1, Pezizales 2 and Pezizales 3) appeared on tested larches at a low frequency, but sometimes in high abundance. Tuber spp. appeared at a low frequency and low abundance. The relative abundance of S. grevillei was positively correlated with the age of seedlings, while W. mikolae was negatively correlated with age. Tuber sp. 1 and 2, Pezizales 2, and W. mikolae were positively associated with the basic soil pH values. However, forward selection of the environmental variables showed that only the age of the larch seedlings contributed significantly (F = 11.45, P = 0.02) to the variance in the ECF community. 相似文献
115.
Increasingly, economies that have traditionally benefited from offshoring are losing some of their strategical advantages, with a consequent increase in backshoring by developed economies. This paper describes the phenomenon and tries to shed light on the current challenges, trends, and debates in the area, and on the main determinants of backshoring. A new phenomenon known as nearshoring is also analysed—this consists of relocating some previously offshored manufacturing activities so that they are now close to previous core locations, but not so close as to suffer from disagglomeration effects. This combines the advantages of offshoring and backshoring. 相似文献
116.
Esdras M. Carbajal M. Carolina Zuleta Luellen Swayzer Brian M. Schwartz Maria Carolina Chavarro A. Carolina Ballen‐Taborda Susana R. Milla‐Lewis 《Plant Breeding》2019,138(6):958-966
St. Augustinegrass is well suited for lawns and commercial landscapes. While many genotypes are cross‐fertile, all cultivars are propagated vegetatively in sod production. To ensure varietal purity, development of sterile triploid hybrids by crossing tetraploid and diploid genotypes has been successfully used in other warm‐season turfgrasses. Applying this model in St. Augustinegrass would be beneficial to sod producers and turf managers who require purity for certification and uniformity for performance, respectively. This study was conducted to develop colchicine‐induced tetraploid lines of St. Augustinegrass. Seeds of cultivar ‘Raleigh’ were treated with four colchicine concentrations at four exposure times. A non‐treated control was included among the treatments. Seedlings that germinated were screened for genome size changes using flow cytometry. Line DSA 13005 and two progeny lines derived through selfing, DSA 16001 and DSA 16016, were corroborated as tetraploids (2n = 4x = 36) through chromosome counts. These lines will be used in future breeding efforts to attempt development of sterile triploid cultivars of St. Augustinegrass. 相似文献
117.
Carlos A Martínez-Palacios Maria Gisela Ríos-Durán Jorge Fonseca Madrigal Mayra Toledo Cuevas Angela Sotelo López & Lindsay G Ross 《Aquaculture Research》2008,39(7):738-747
The Mexican silverside, Menidia estor, is a species with great regional importance and with very high prices in local markets. Unfortunately, due to high fisheries pressure, environmental degradation and pollution, the species has become endangered. Recently, there has been much progress in the biotechnology of this species, aimed at its culture, and the present paper describes the advances in feeding and nutrition of those important fish. M. estor is a stomachless, zooplantophagous fish, which also occasionally feeds on small fish and crustaceans in the adult stage. Studies on the digestive enzymatic activities show high proteolytic capacity and a late or different model of digestive maturation from that described for marine stomach fish. Nutritional studies on M. estor have shown that juveniles have dietary requirements of about 400 g kg?1 protein and 80 mg kg?1 vitamin C. The upper level of dietary carbohydrate for good growth and survival for juveniles is about 150 g kg?1. Based on the high docosahexaenoic acid (DHA) content in flesh when fed on diets low in DHA, it is believed that the species has the capacity to biosynthetize >20‐carbon fatty acids from 18‐carbon fatty acids. The high levels of DHA in flesh makes this fish a very significant potential component of human nutrition. Using these findings the first practical diets for commercial culture of the species have been developed. 相似文献
118.
Brown shrimp (Farfantepenaeus aztecus) density distribution in the Northern Gulf of Mexico: an approach using boosted regression trees
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Jose T. Montero Tanya A. Chesney Jennifer R. Bauer John T. Froeschke Jim Graham 《Fisheries Oceanography》2016,25(3):337-348
The estuarine‐dependent brown shrimp, Farfantepenaeus aztecus, is a significant commercial fishery and important species in the Gulf of Mexico (GOM) ecosystem as well as being a key component in energy transfer between benthic and pelagic food web systems. Because of the economical and ecological importance of brown shrimp, we developed a spatial population model to identify places of high shrimp density under a set of spatial, environmental and temporal variables in the Northern Gulf of Mexico (NGOM). We used fisheries‐independent data collected by the Southeast Area Monitoring and Assessment Program (SEAMAP) from 1992 to 2007 (summer and fall seasons). The relationship between the predictor variables and shrimp density was modeled using Boosted Regression Trees (BRT). Within the environmental variables included in the model, bottom type and depth of the water column were the most important predictors of shrimp density in the NGOM. Spatial predictions performed using the trained BRT model for summer and fall seasons showed a spatial segregation of shrimp density. During the summer, higher densities were predicted near the Texas and Louisiana coast and during the fall, higher densities were predicted further offshore. The model performed well and allowed successful prediction of brown shrimp hot spots in the NGOM. Model results allow fisheries managers to evaluate the potential impact from fisheries on the resource and to develop future fisheries management strategies, understand the biology of brown shrimp as well as assess the potential impacts of oil spills or climate change. 相似文献
119.
Characterizing environmental and spatial variables associated with the incidental catch of olive ridley (Lepidochelys olivacea) in the Eastern Tropical Pacific purse‐seine fishery
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Jose T. Montero Raul O. Martinez‐Rincon Selina S. Heppell Martin Hall Michael Ewal 《Fisheries Oceanography》2016,25(1):1-14
In the Eastern Tropical Pacific (ETP), a region of high fishing activity, olive ridley (Lepidochelis olivacea) and other sea turtles are accidentally caught in fishing nets with tuna and other animals. To date, the interaction between fishing activity, ocean conditions and sea turtle incidental catch in the ETP has been described and quantified, but the factors leading to the interaction of olive ridleys and fishing activity are not well understood. This information is essential for the development of future management strategies that avoid bycatch and incidental captures of sea turtles. We used Generalized additive models (GAM) to analyze the relationship between olive ridley incidental catch per unit effort (iCPUE) in the ETP purse‐seine fisheries and environmental conditions, geographic extent and fishing set type (associated with dolphins, floating objects or in free‐swimming tuna schools). Our results suggest that water temperature, set type and geographic location (latitude, longitude and distance to nesting beaches) are the most important predictor variables to describe the probability of a capture event, with the highest iCPUE observed in sets made over floating objects. With the environmental predictors used, sea surface temperatures (SST) of 26–30°C and chlorophyll‐a (chl‐a) concentrations <0.36 mg m?3 were associated with the highest probability of an incidental catch. Temporally, the highest probability of an incidental catch was observed in the second half of the year (June to December). Four regions were observed as high incidental catch hotspots: North and south of the equator between 0–10°N; 0–10°S and from 120 to 140°W; and along the Colombian coast and surrounding regions. 相似文献