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801.
Genetic mapping of sedimentation volume across environments using recombinant inbred lines of durum wheat 总被引:13,自引:0,他引:13
A. Blanco M. P. Bellomo C. Lotti T. Maniglio A. Pasqualone R. Simeone A. Troccoli N. di Fonzo 《Plant Breeding》1998,117(5):413-417
SDS-sedimentation volume (SV) is a biochemical index widely used to evaluate flour quality in durum and bread wheats. Significant association between SV and endosperm proteins (gliadin, high-molecular-weight- and low-molecular-weight-glutenin subunits) have been reported. Protein loci, however, account for only a portion of the total genetic variability. The objective of this study was to identify and locate quantitative trait loci (QTLs) associated with SV in a set of recombinant inbred (RI) lines, derived from a cross between the cv.‘Messapia’ of durum wheat and the accession MG4343 of the var. dicoccoides, and characterized for 259 genetic and molecular (RFLP) markers. Significant differences were detected for the quality index in the six environments examined, while the pattern of variability was that of a quantitative trait. Regression analysis of marker loci and sedimentation volume indicated, as expected, that chromosome 1B, on which are located the Gli-B 1/Glu-B 3 loci for some gliadin and glutenin subunits, is important for wheat quality. Two additional regions located on chromosomes 6AL and 7BS, and four regions on 1AL, 3AS, 3BL and 5AL, were shown to have single-factor effects on sedimentation volume at P < 0.001 and P < 0.01, respectively. Positive effects were contributed by both parents. A multiple linear regression model consisting of seven significant loci on different chromosomes explained 62–91% of the genotypic variation of the trait. The availability of linked markers to QTLs may facilitate the genetic dissection of quantitative traits and the early selection in wheat breeding programmes. 相似文献
802.
Vernica Elizabeth Viau Jonatan Gabriel Prez Ana Laura Tomas Pablo Andrs Fracas Florencia Beln Veira Itzick Vatnick Laura Susana Lpez Greco 《Aquaculture Research》2020,51(9):3847-3864
Neocaridina davidi is a popular shrimp in the aquarium industry; however, information regarding its husbandry is scarce. In this study, we investigated the contribution of biofilm to its life cycle, comprising three successive phases: (1) the evaluation of biofilm growth on plastic nets (PN), plastic sheets (PS) and agrovelo (AV); (2) the reproduction of adult shrimp to get juveniles (JI); and (3) the effects of biofilm on the survival and growth performance of JI. Trials were performed in aquaria with zero water exchange and natural environmental conditions. Biofilm was composed mainly of microalgae, diatoms, cyanobacteria and ciliates and used as the sole diet. Survival, biomass and biochemical reserves of JI reared in this culture system were significantly higher in the presence of PN and AV substrates. The occurrence of ovarian maturation and egg incubation of female shrimp in these treatments indicate that biofilm supplied the energy required for somatic growth and fecundity. Harvested females also displayed the size and the red pigmentation associated with premium pricing. Based on these results, it is concluded that N. davidi can complete the life cycle and display characteristic life history traits in a low‐cost biofilm technology system without losing economic value as ornamental species. 相似文献
803.
804.
María Asunción Piedecausa Felipe Aguado-Giménez Benjamín García-García Gabriel Ballester & Trevor Telfer 《Aquaculture Research》2009,40(15):1703-1714
The physico-chemical characteristics of particulate wastes of Sparus aurata and Dicentrarchus labrax were investigated. Changes in the dimensions, settling velocity and total ammonia nitrogen (TAN) leached from commercial feed pellets were investigated after soaking. Also, the settling velocity and TAN leached from faecal pellets of these fish were assessed at 15 and 25 °C. The settling velocity of feed pellets was influenced positively by pellet weight and negatively by immersion length as a result of changes in pellet dimensions after soaking. The settling velocity of faecal pellets was determined by pellet weight. The experimental design did not allow identification of any consistent effect of water temperature on settling velocity. Total ammonia nitrogen leaching over time from feed and faecal pellets was successfully explained by means of a first-order kinetic equation. For feed pellets, water temperature significantly affected the speed of the process and the time at which the maximum TAN leached was reached, but did not influence the maximum TAN leached. Leaching was related to feed pellet size, and so the smaller the pellet, the higher the leaching. Total ammonia nitrogen leaching from faecal pellets was greater per unit weight than in feed pellets. However, neither water temperature nor fish species influenced TAN leaching from faeces. 相似文献
805.
Amalia Pérez‐Jiménez María Carmen Hidalgo Amalia E. Morales Marta Arizcun Emilia Abellán Gabriel Cardenete 《Aquaculture Research》2009,41(1):111-119
Determining an adequate macronutrient balance is essential to guarantee the production success. As protein is the limiting component for fish food, the utilization of lipids or carbohydrates as partial substitutes of this nutrient is a challenge to improve its use. In order to get an approximation of the maximum levels of utilization for carbohydrates and/or lipids and determine the most adequate macronutrient to partly replace protein as the main energy source of diets for dentex (91.7 ± 1.4 g mean weight), four experimental diets with different protein:lipid:carbohydrate percentages (43/16/28, 43/24/4, 38/19/28 and 38/24/13) were tested for 13 weeks. The results indicated the possibility of using 38% of dietary protein without affecting growth performance, under the experimental conditions. There were no differences among the four diets either in most of the nutritive utilization indicators or in the body composition and haematological parameters. The influence of dietary composition was only observed in the feed intake, being higher with more dietary carbohydrates, and the hepatosomatic index and protein efficiency ratio, showing more elevated values in diets with a higher lipid level. The dentex capacity of using both carbohydrates and lipids efficiently to obtain the necessary energy for its correct growth, as well as to compensate the energetic ‘vacuum’ caused by the dietary protein reduction, under the assayed conditions, was confirmed. 相似文献
806.
Gabriel Gana Bake Masato Endo Atsushi Akimoto Toshio Takeuchi 《Fisheries Science》2009,75(5):1275-1283
A 70-day feeding trial was conducted to evaluate the suitability of recycled food wastes [food industry waste (FIW) and soy
sauce waste (SSW)] as protein sources in the diet of Oreochromis niloticus fry. Diets were formulated that contained 0 and 20–22%, respectively, recycled food wastes, namely D1 (0% recycled food waste),
D2 (20% FIW), D3 (10% FIW and SSW, respectively), D4 (20% FIW and tryptophan), and D5 (22% SSW). Although feed efficiency,
net protein retention, and protein efficiency were not significantly different among fish on the different diets (p > 0.05), those on D3 had a better growth performance than the controls (D1). Fish fed diet D4 (tryptophan supplement) had
a higher final weight gain than those fed D2, in addition to the other growth parameters, but these differences were not significant
(p > 0.05), with the exception of total feed intake. D1 produced fish with higher carcass protein, while fish fed on D3 had
the highest lipid content. There was no significant difference between groups in terms of carcass moisture and ash contents.
These findings show that the proper combination of recycled food waste is suitable for use in the production of fish feed
and may ultimately result in reductions in the level of fishmeal in aquafeeds. 相似文献
807.
Lenir Fátima Gotz Nerilde Favaretto Gabriel Barth Paulo Sergio Pavinato Volnei Pauletti 《Soil Use and Management》2023,39(1):606-617
The benefits of manure as a source of nutrients for plants and to improve soil quality are well-known. Monitoring of manure application is needed if environmental issues are to be prevented. In particular, the availability and accumulation of phosphorus (P) has to be subject to rigorous monitoring. This study aims to both evaluate the efficacy of the resin method in extracting inorganic labile P in soils under the long-term application of dairy liquid manure (DLM), and verify the influence of DLM on the recovery of applied P and soil legacy P. To realize our objectives, two long-term field experiments were established under a no-tillage system with annual DLM application on sandy clay loam (sandy Oxisol) and clayey (clayey Oxisol) soils. Treatment consisted of DLM applications (0, 60, 120, 180 m3 ha−1 year−1), independent of mineral fertilizer. Soil samples were taken from the 0–5, 5–10 and 10–15 cm layers after 10 years from the beginning of the trial. A single extraction with resin underestimated inorganic labile P; however, successive extractions were able to take up 43% and 26% of the total P in sandy and clayey Oxisols, respectively, whereas in a single extraction the take-up was 17% and 8% from the same soils, respectively. The resin method was more effective in extracting P from the sandy Oxisol. Thus, when interpreting soil P contents for fertilizer planning, the soil texture should be taken into account. DLM application decreased P recovered from applied P, ranging from 54% to 83% (sandy), and 43% to 67% (clayey), and substantially increased soil legacy P. 相似文献
808.
Christian Spalthoff Vincent L. Salgado Narayanan Balu Michael D. David Philip Hehlert Huazhang Huang John E. Jones Ramani Kandasamy Gabriel A. Knudsen Katherine R. Lelito James B. Machamer Alexandre Nesterov Michael Tomalski Gregory D. Wahl Barbara J. Wedel Martin C. Göpfert 《Pest management science》2023,79(5):1635-1649
The cover image is based on the Research Article The novel pyridazine pyrazolecarboxamide insecticide dimpropyridaz inhibits chordotonal organ function upstream of TRPV channels by Christian Spalthoff et al., https://doi.org/10.1002/ps.7352