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101.
Ruiz Maria Luiza Owatari Marco Shizuo Yamashita Marcela Maya Ferrarezi José Victor Saffadi Garcia Patricia Cardoso Lucas Martins Maurício Laterça Mouriño José Luiz Pedreira 《Tropical animal health and production》2020,52(1):167-176
Tropical Animal Health and Production - The aims of this study were to evaluate the inclusion of different concentrations of Lactobacillus plantarum in Nile tilapia diet and to verify histological... 相似文献
102.
Robles Jimenez Lizbeth E. Ruiz Perez Jose A. Nicolas Di Lorenzo Chay Canul Alfonso J. Ramirez-Rivera Julio Cesar Villegas-Estrada Daniela Vargas-Bello-Pérez Einar Gonzalez-Ronquillo Manuel 《Tropical animal health and production》2020,52(3):1257-1267
Tropical Animal Health and Production - Currently for the reduction of methane (CH4) emissions are using fodder rich in condensed tannins, however, not yet known exactly how they act in the rumen... 相似文献
103.
Nursery Crop Growth Response to Municipal Biosolids: Species Salt and Xeric Adaptation a Key Factor?
Geno A. Picchioni Julie Ruiz Ryan M. Goss John G. Mexal 《Compost science & utilization》2013,21(3):138-152
ABSTRACTGrowth responses of potted ornamental crops to municipal biosolids in the semiarid southwestern USA are not adequately known. In 10- to 11-wk greenhouse pot studies, we evaluated the effects of dried biosolids-amended growing media on four ornamental crop species: Garden chrysanthemum (Dendranthema Xgrandiflorum ‘Megan’), butterfly bush (Buddleia davidii ‘Nanho Blue’), Japanese honeysuckle (Lonicera japonica ‘Purpurea’), and blanket flower (Gaillardia Xgrandiflora ‘Goblin’). The biosolids were composted without bulking agents (100% sewage sludge) and incorporated into growing media at rates ranging from 0 to 593 kg m?3, or 0 to 72% by volume. Biosolids increased substrate pH from 5.8 to 7.2 and electrical conductivity (EC) from 2.6 to 47.3 dS m?1. Any addition of biosolids (≥30 kg m?3) reduced total plant dry matter (DM) of chrysanthemum. Conversely, shoot DM of blanket flower and butterfly bush increased by four- to five-fold at biosolids rates of 59 to 148 kg m?3 (7 to 18% by volume) with corresponding increases in shoot N and P concentrations. Biosolids rates higher than 148 kg m?3 reduced top growth of the latter two species and of Japanese honeysuckle. For all species, growth reductions with excessive biosolids rates likely resulted from osmotic stress and specific NH4 toxicity. However, based on the substantial growth stimulations at moderate biosolids rates, xeric and salt-adapted species, such as blanket flower and butterfly bush, may be ideally suited for expanding the use of highly saline biosolids at semiarid nursery production sites. 相似文献
104.
A. I. Milder B. Fernndez‐Santos C. Martínez‐Ruiz 《Land Degradation \u0026amp; Development》2013,24(1):39-46
In this study, we combined the analysis of a coenocline with Huisman–Olff–Fresco (HOF) modelling of species behaviour to describe colonization patterns of woody species on reclaimed coal wastes in northern Spain. We hypothesize that fine‐scale variation in abiotic factors along the forest‐grassland gradient that appears after mining restoration affects colonization pattern of woody species. To understand these factors, we analysed changes in floristic composition and abundance of the main woody colonizers according to the spatial distance from forest limit, as well as the spatial variability of some edaphic and microclimatic parameters. Our results showed how the primary coenocline extracted from DCA1 reflected a gradient in environmental conditions influencing the species composition of the woody plant communities, from the more shade, moist and dense forest on acid and rich soils to the open, dry and oligotrophic grassland. The colonization pattern of woody species is affected by fine‐scale variations in abiotic factors, such as the increase in pH, P, light, and the decrease in K, N, C/N, organic matter and soil moisture, from the forest to the restored mine. Most species HOF modelled showed monotone responses with decreasing trends along the environmental gradient from forest to mine, being Quercus petraea the species clearly dominant in the forest. On the contrary, Cytisus scoparius and Genista florida colonize intensely in the mine area, reaching the maximum abundance around 15 and 10 m distance from the forest limit, respectively. We conclude that the composition of woody species in the forest is not a good predictor of the colonizing intensity, not even of the species composition in the mine area. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
105.
106.
Effects of N fertilization on yield for low-input production in Spanish wheat landraces (Triticum turgidum L. and Triticum monococcum L.) 总被引:1,自引:0,他引:1
A core subset of Spanish durum wheat landraces was evaluated at two nitrogen levels (80 and 220 kg/ha) to identify landrace genotypes adapted to low N production. Yield differences were statistically significant between N levels and among genotypes at both levels. Fifty-one per cent of the landraces yielded significantly more at low than at high N (low-N varieties) while 26% had a positive (high-N varieties) and 23% an indifferent (indifferent-N varieties) response to N fertilizer. No significant agromorphological differences were found among low and high-N varieties at low N level that conferred some advantage to low-N varieties. In contrast, high-N varieties possessed longer grain-filling period under high N level. Phenological characters showed an important influence on yield and on the performance of the varieties within each subgroup. The traits affecting grain yield most positively, mainly the low-N varieties, were long filling period and earliness. Five entries were selected for prebreeding to low N adaptation. 相似文献
107.
Light interception and radiation use efficiency in temperate quinoa (Chenopodium quinoa Willd.) cultivars 总被引:1,自引:0,他引:1
Sea level quinoas are grown at low altitudes in Central and Southern Chile. Both sensitivity to photoperiod and response to temperature largely determine quinoa adaptation, but crop biomass production must be quantified to evaluate agronomic performance. The objectives of this work are: (i) to characterize development effects on leaf area evolution for genotypes of sea level quinoa differing in cycle length, (ii) to quantify the extinction coefficient (k) for photosynthetically active radiation (PAR) and radiation use efficiency (RUE) from emergence up to the beginning of grain filling and (iii) to identify which crop attributes related to canopy architecture should be considered to improve biomass production. Four cultivars (NL-6, RU-5, CO-407 and Faro) were cropped in Pergamino (33°56′S, 60°35′W, 65 m a.s.l.), Argentina, at three densities (from 22 to 66 plants m−2) in two consecutive years under field conditions with adequate water and nutrient supply. Thermal time to first anthesis and maximum leaf number on the main stem were linearly correlated (r2 = 0.87; p < 0.0001). Leaf area continued to increase during the flowering phase, notably in NL-6, the earliest genotype. There were significant differences in maximum plant leaf area between cultivars. Increasing density reduced plant leaf area but effects were comparatively small. Estimated k was 0.59 ± 0.02 across genotypes and was higher (p < 0.05) for 66 plants m−2. Values for RUE changed as cumulative intercepted PAR (IPAR) increased; at initial stages of development RUE was 1.25 ± 0.09 g MJ IPAR−1, but if cumulative IPAR was higher than 107.5 ± 10.4 MJ IPAR m−2, RUE was 2.68 ± 0.15 g MJ IPAR−1. That change occurred when leaf area index (LAI) and fraction of PAR intercepted were still low and ranged from 0.61 to 1.38 and from 0.33 to 0.51, respectively. No significant association was found with any developmental stage. Our results agreed to the notion that RUE variation during pre-anthesis phases is largely determined by LAI through its effect on radiation distribution within the canopy. Biomass production could be improved if periods of interception below 50% of incoming PAR were reduced to ensure high RUE. This seems to be possible in temperate areas both by the use of late genotypes with a higher number of leaves on the main stem and by early genotypes provided adequate plant density is chosen. Early increment in LAI and overlapping of the leaf area increase period with the flowering phase are desirable strategies for earliest genotypes to maximize yield. 相似文献
108.
Enrique Ritter Leire Barandalla Raquel López José Ignacio Ruiz de Galarreta 《Potato Research》2008,51(3-4):301-311
Native potato species (NPS) are cultivated potatoes which do not belong to S. tuberosum ssp. tuberosum. They are maintained by the farmers of the Andes for subsistence under harsh environmental conditions where other potatoes cannot compete. Within the huge phenotypic variability between and within these species certain accessions possess resistances to different pests and diseases, remarkable culinary and processing quality and favourable nutritional properties. We present first evaluation results of a set of NPS for these characters and discuss prospects for exploiting this valuable germplasm for breeding and for developing novel products for niche markets. 相似文献
109.
Reduced Impact Logging (RIL) has traditionally been described as a set of forest management practices that reduce logging impacts and improve productivity. In this paper, we review the evolution of the logging sector in the Congo basin since the early 20th century. We argue that logging in the Congo basin has been little influenced by RIL until the recent regional Forestry Law reforms that started in Cameroon in 1994. RIL has not been integrated into the logging sector of the region as an independent body of knowledge, but more as a complement of the new mandatory management plans. In spite of its proven environmental and economic advantages, the role of RIL in improving forest management has been poorly understood, and we identify some causes of this situation. Finally, based on a regional study of 30 concessions, we analyse the frequency of some RIL-related practices and their relation with markets and certification schemes. We conclude that a clear definition of what RIL techniques are embraced by the logging sector is needed if RIL is to fully benefit from the recent development of new market and logging schemes based on certification, improved logging efficiency and a more transparent chain of custody. 相似文献
110.
Frederic Aparicio Salvador Soler José Aramburu Luis Galipienso Fernando Nuez Vicente Pallás Carmelo López 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(1):117-123
A polyprobe for the simultaneous detection by non-isotopic molecular hybridisation has been developed to detect any of the
following six viruses causing important economic losses in tomato crops: Tomato spotted wilt virus, Tomato mosaic virus, Pepino mosaic virus, Cucumber mosaic virus, Potato Y virus and Parietaria mottle virus. The polyprobe detected all six viruses with similar sensitivity to that obtained using individual riboprobes. In addition,
we evaluated the possible use of the tissue-printing as a sample preparation technique applied to routine diagnosis of tomato
plants with the polyprobe.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献