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971.
Gustavo Rubén Rodríguez Guillermo Raúl Pratta David Rodolfo Liberatti Roxana Zorzoli Liliana Amelia Picardi 《Euphytica》2010,176(1):137-147
A tomato cultivar with high quality fruit and a long shelf life is a main goal in tomato breeding and it would be achieved
using wild germplasm. The objective of this work was to explore the inheritance for fruit quality traits, especially fruit
shelf life, in three tomato crosses using a standard Argentinean cultivar (Ca, cv ‘Caimanta’), a ripening mutant (nor, homozygous
for the nor gene) of Solanum lycopersicum, and a wild cherry type (Ce, LA1385 of S. lycopersicum var. cerasiforme). The wild parent had a shorter fruit shelf life than the mutant genotype but higher than Ca. When the Ce genotype was analyzed
in hybrid combination, the F1 (Ca×Ce) was similar to the wild genotype for shelf life whereas the F1 (nor × Ce) had a longer shelf life. Both F1 crosses and backcrosses to the cherry type genotype had significantly lower fruit weight than the cultivated genotypes but
higher than the cherry type parent. In the F2 analysis, it was found that the inheritance underlying quality traits is complex since non allelic interactions were detected.
A significant additive genetic variance was found for fruit shelf life as well as for other fruit quality traits in each cross.
The genetic parameters analyzed by mean values and variances in parental, F1 and F2 and backcross generations indicated that the cross between the normal ripening cultivar and LA1385 of S. lycopersicum var. cerasiforme offers the best possibility to obtain long shelf life tomato genotypes with good fruit quality. 相似文献
972.
Stervins Alexis Luis G. García-Montero Ana J. Hernández Antonio García-Abril Jesús Pastor 《Agroforestry Systems》2010,79(3):381-391
In the jaragua-bahoruco-enriquillo biosphere reserve, located on the southern border between the Dominican Republic and Haiti,
there are depressed rural areas with soils with high content in Cadmium and other heavy metals which originate naturally in
the geological substrate. Data from 80 soils and an inventory of 76 plantations (coffee and kidney bean were used) to design
a GIS (geographic information systems) tool which integrated statistical multivariate methods, soil parameters including heavy
metal content into models of land planning, agricultural development, forests and protection of the health of the area’s inhabitants
and the natural environment. This GIS tool is based on raster models of an open source, which use combination and reclassification
operations based on the maps, geostatistical methods (Kriging), statistical analyses external to the GIS, and cartography
of limiting and excluding particular factors for crops (including heavy metal soil content). The GIS tool developed discriminates
extreme situations in sustainable agroforestry planning in contaminated rural areas of the Caribbean, Central America and
other tropical regions. 相似文献
973.
Maria Ivanilda de Aguiar Stoécio Malta Ferreira Maia Francisco Alisson da Silva Xavier Eduardo de Sá Mendonça João Ambrósio Araújo Filho Teógenes Senna de Oliveira 《Agroforestry Systems》2010,79(3):277-289
Inadequate soil management practices adopted in the Brazilian semi-arid region contribute to erosive processes. Agroforestry
systems (AFs) have been considered an alternative to reduce water erosion. This study aimed to evaluate the impact of two
alternatives AFs, a traditional and an intensive cropping system on the losses of sediments, water, organic carbon and nutrients
caused by water erosion in comparison to the natural vegetation (caatinga) in a semi-arid region of northeastern Brazil. The
agroecosystems studied were: agrosilvopasture (AGP) which consisted of an alley cropping system, cultivated with Leucaena leucocephala and maize, within an area composed by 22% of native trees (200 native trees per hectare) which was grazed during the dry
season; silvopasture (SILV) that was composed by 38% of native trees (260 trees per hectare) with a stocking rate of 20 ewes
during whole year; traditional agrosilvopasture (TRAG) being managed as following: total deforestation, burning of the residues,
cropped with maize for 2 years (1998 and 1999) and fallow during 8–10 years; and intensive cropping (IC) system which was
deforested and burned in 1997 followed by cultivation of maize from 1998 to 2002, and thereafter by a fallow period of 8–10 years
similar to TRAG. Two areas of native forest (NF1, NF2) known as ‘caatinga’, used as grassland during the dry season and as
a source of wood, were selected and used as reference of steady state in the comparative study in relation to the cultivated
sites. Sediment and water losses as a result of erosion were collected during two rainy seasons, i.e. 2003 and 2004, and nutrients
and organic carbon contents were determined. Soil samples were collected and organic carbon, pH in water, pH in KCl, water
dispersible clay (WDC) and hydraulic conductivity (K0) were measured. In 2003, sediment and water losses did not differ significantly among all treatments. However, in 2004, TRAG
(0.70 Mg ha−1) and NF1 (1.37 Mg ha−1) showed the highest sediment losses, whereas TRAG and IC presented the highest water losses. On average, nutrients losses
in cropped areas were lower than in natural vegetation (NF1, NF2). The alternative AFs (AGP, SILV) were efficient to reduce
water erosion effects when compared to the most common agricultural practices adopted in the region, being highly recommended
as sustainable technical alternatives for food production in the region. 相似文献
974.
Susana Pascual Guillermo Cobos Elena Seris Manuel González-Núñez 《Journal of pest science》2010,83(2):121-133
The particle film technology based on processed kaolin sprays has been recently introduced for the control of the olive fruit
fly Bactrocera oleae (Rossi), the key pest of olive groves. A 3-year field experiment was conducted from 2005 to 2007 at Villarejo de Salvanés,
Spain to assess the efficacy of a kaolin-based product (Surround WP) for controlling B.
oleae and two other olive insect pests: the olive black scale Saissetia
oleae (Olivier) and the olive psyllid Euphyllura
olivina (Costa). The effects of Surround WP on the arthropod community of olive trees and on natural enemies were also evaluated.
In a high olive fruit fly pressure year (2007), Surround WP sprays significantly reduced the incidence of B. oleae and that of S. oleae. However, Surround WP treatments did not have any effect on E. olivina populations. Both the abundance and the diversity of arthropods were reduced by Surround WP treatment. The principal response
curve (PRC) analysis revealed a significant deleterious effect of Surround WP on the natural enemy arthropod community of
the olive grove. The most affected taxa were the following: the coccinellids Scymnus mediterraneus Iablokoff-Khnzorian, Stethorus punctillum Weise and Hyperaspis reppensis (Hbst.); the mirid Brachynotocoris ferreri n. sp. Baena (in litteris); different species of Orius and the families of Philodromidae, Scelionidae, Pteromalidae, Chrysopidae and Aphelinidae. Processed kaolin is proposed as
an alternative to chemical control of the olive fruit fly. However, the effect of processed kaolin treatments on natural enemies
should be taken into account in a rational pest control programme. 相似文献
975.
The inland region of Galicia (NW Spain) marks the boundary between the Atlantic climate of the coastal area and the typical
Mediterranean climate of central Spain. Compared to the Atlantic coast, climate in this area has a pronounced summer drought,
lower annual precipitation, and higher annual thermal oscillation. Despite the high productivity and ecological importance
of maritime pine in inland Galicia, local forest reproductive material (FRM) of high genetic quality is not available for
this area. Seed sources originating elsewhere and of unknown adaptation to this area are commonly used for reforestation.
With the aim of finding new sources of FRM for this region and exploiting the genetic gains of existing breeding programmes,
we analysed the performance in field conditions of improved families of the Coastal Galicia (CG) and Western Australia (WA)
breeding programmes. Growth, stem characteristics and branch habit were evaluated in five progeny trials established following
a coastal-to-inland gradient. Likelihood-based analyses were used to estimate genetic correlations between environments and
to test statistically for causes and patterns of genotype × environment interaction. Because of the strong non-random spatial
structures and heterogeneity of residual variances, the analyses were carried out using heterogeneous residual variance mixed
models on spatially adjusted data. The results indicated that there is not sufficient evidence to subdivide Galicia into the
two current deployment areas. Interaction patterns do not reveal significant differences between zones, and crossover interactions
for height growth are present both between and within areas. On the inland sites, the Atlantic improved materials clearly
outperformed unimproved seedlots tested in adjacent provenance trials, suggesting the feasibility of using both the CG and
WA breeding materials as sources of FRM for reforestation in inland Galicia. Of the two, the WA material showed excellent
results for all traits. The inclusion of this material into the Galician maritime pine breeding population should be strongly
considered. 相似文献
976.
977.
Evaluation of poultry by‐product meal as partial replacement of fish meal in practical diets for juvenile tench (Tinca tinca L.)
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Álvaro González‐Rodríguez Jesús D Celada José M Carral María Sáez‐Royuela Vanesa García Juan B Fuertes 《Aquaculture Research》2016,47(5):1612-1621
The aim of this study was to evaluate different replacement levels of fish meal (FM) by poultry by‐product meal (PBM) on survival, growth performance and body composition of juvenile tench (Tinca tinca). A 90‐day experiment was conducted with 5 month‐old juveniles (31.95 mm total length, 0.396 g weight). Eight practical diets (50% crude protein) differing in the level of replacement of FM protein by PMB protein were tested: 0% (control), 25%, 31%, 37%, 43%, 49%, 55% and 61% corresponding to 0, 184.8, 229.2, 273.5, 317.8, 362.1, 406.5 or 450.8 g PBM kg?1 diet respectively. Significant differences were not found (P > 0.05) between 25% replacement of FM protein by PBM protein (184.8 g kg?1 PBM in diet) and control diet. At higher replacement levels, fish had significantly lower growth, higher feed conversion ratio and lower protein productive value (P < 0.05). Fish with externally visible deformities ranged from 1.1% to 3.3%. The relation among amino acid profiles of the diets, body composition, growth performance of juveniles and amino acid requirements of other fish species is discussed. Up to 184.8 g PBM kg?1 diet can be included in diets for juvenile tench without impairing growth performance. 相似文献
978.
Elvia A Espinosa Moya César A Angel Sahagún J Mario Mendoza Carrillo Pedro J Albertos Alpuche C Alfonso Álvarez‐González Rosario Martínez‐Yáñez 《Aquaculture Research》2016,47(6):1716-1726
Aquaponics is a recirculating aquaculture system (RAS), where plants and aquatic animals are grown using the same water. In these systems, plants act as part of biological filters. The cultivation of O. basilicum, Menta x piperita and M. spicata is commonly integrated to the production of O. niloticus in aquaponics. The aim of this study was to evaluate the ability of these herbs as part of biological filters for tilapia intensive production in aquaponics. Various physicochemical parameters were evaluated as water quality indicators. N and P content in the different elements of the system were also measured. Results showed that for tilapia growing the three herbaceous evaluated could be used as part of the biological filters in aquaponics, because they remove significant concentration in nitrogen compounds and phosphates; however, there were no differences among species. There was a positive relationship between the time and the levels of NH4 and therefore NO3? in the water. The pH, temperature and dissolved oxygen were kept at appropriate ranges for tilapia. The electrical conductivity and total dissolved solids were in suitable levels for growing herbaceous, which adapted to flooded substrates, with water constantly moving and high concentration of dissolved oxygen. A key parameter to consider is the oxygen concentration in water when herbaceous is used in aquaponics, due to the high input of this element for these species need, especially basil. Tilapia largely incorporated N and P entering the system. 相似文献
979.
This work aimed to determine whether a minimum provision of marine oil in practical diets for Litopenaeus vannamei is required when replacing fish meal (FM) by soy protein concentrate (SPC). The study consisted of three growth experiments conducted in 500‐L tanks with 70 shrimp m?2. In experiment #1, FM was progressively replaced by SPC as fish oil (FO) levels increased with a consistent input of whole squid meal (WSM). In experiment #2, FM was replaced by SPC under two levels of FO (10 or 20 g kg?1) without the presence of a feeding effector. In experiment #3, three dietary levels of krill meal (KRL) and WSM (5, 10 and 20 g kg?1) were included in a basal diet containing SPC and low levels of FM. Results showed that under a clear‐water condition, the dietary levels of FO in practical diets for L. vannamei have a significant impact on the amount of FM that can be replaced by SPC. As much as 31% replacement of FM/SPC was possible with 20 g kg?1FO. Whenever dietary fat was adjusted by using FO as a lipid source, complete replacement of FM by SPC was achieved with no negative effect on shrimp growth. 相似文献
980.
José Luis Arredondo‐Figueroa Jesús Trinidad Ponce‐Palafox Keiko Shirai‐Matsumoto Ángel Pérez‐Zavaleta Irene De Los Ángeles Barriga‐Sosa Arturo Ruiz Luna 《Aquaculture Research》2013,44(6):966-973
An experiment was carried out to analyse the effects of substituting fish‐meal (FM) with soya bean meal and shrimp protein hydrolysate (SPH) on the percent survival, growth rate, feed efficiency and molt frequency of redclaw crayfish hatchlings, Cherax quadricarinatus. The experiment was performed in a closed recirculating‐water system over a 56‐day period. Five diets were tested: a control diet (SPH0) comprising 100% FM without SPH, and four diets with 2.5%, 5.0%, 10.0% and 15.0% SPH substitution (diets SPH2.5, SPH5, SPH10 and SPH15 respectively). Analysis of water quality indicated that it was adequate to maintain a good growth and survival of hatchlings. The results showed that 100% survival was obtained for hatchlings fed with SPH5, SPH10 and SPH15 diets. Higher mean values of final weight were obtained for the SPH5 diet. The highest weight gain was observed in SPH2.5 and SPH5 diets. Hatchlings showed similar specific growth rates for all diets. The efficiency rate of the SPH15 diet was lower compared to the other diets. Overall, individual feed consumption was higher in hatchlings fed diets of SPH5 and SPH15. It is recommended that 5.0% of SPH could be included in diets of hatchling redclaw crayfish to improve their growth efficiency. 相似文献