Spanish Journal of Agricultural Research
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In vitro fermentation pattern and acidification potential of different sources of carbohydrates for ruminants given high concentrate diets
No full textThe in vitro fermentation pattern of five sources of carbohydrates of differing nature (maize grain, MZ; sucrose, SU; wheat bran, WB; sugarbeet pulp, BP; and citrus pulp, CT) under conditions of high concentrate diets for ruminants was studied. A first 8 h incubation trial was performed under optimal pH using inoculum from ewes given a fibrous diet, to compare fermentative characteristics of substrates. As planned, incubation pH ranged within 6.3 to 6.6. The gas produced from CT was higher than MZ, SU and BP from 4 and 6 h onwards, and at 8 h, respectively (p<0.05). There were no differences (p>0.05) on total volatile fatty acid (VFA) concentration, nor on acetate or propionate proportions, but butyrate was lowest (p<0.05) with CT and BP. The second incubation trial was performed in a poorly-buffered medium, with inoculum from ewes given a concentrate diet. All substrates showed a gradual drop of pH, being lowest with SU after 4 h (p<0.05). Throughout the incubation, gas production was highest with CT and lowest with MZ and BP (p<0.05). Total 8 h VFA concentration was higher with CT than BP, SU and MZ (p<0.05). Acetate proportion was higher, and that of propionate lower, with BP than WB (p<0.05), butyrate proportion being higher with MZ and WB than with BP and CT (p<0.05). Lactic acid concentration was higher (p<0.05) with SU than WB and BP. Fermentation characteristics and acidification potential of feeds depend on the nature of their carbohydrate fraction, and must be considered for practical applications
Expression of the aldehyde oxidase 3, ent-copalyl diphosphate synthase, and VIVIPAROUS 1 genes in wheat cultivars differing in their susceptibility to pre-harvest sprouting
No full textThe quality of wheat grains is often negatively affected by pre-harvest sprouting (PHS), a complex trait with a poorly understood genetic background. In this study two wheat cultivars differing in their susceptibility to PHS were used to investigate expression of three genes: AAO3, CPS3 and VP1. AAO3 is coding for aldehyde oxidase 3, an enzyme involved in the synthesis of abscisic acid. CPS3 codes for ent-copalyl diphosphate synthase which belongs to the pathway of gibberellic acid synthesis. The product of VP1 (VIVIPAROUS 1) is a transcription factor which controls expression of the former two genes. The study was carried out using both developing and sprouting-induced grains. In Piko, a wheat cultivar susceptible to PHS, accumulation of the AAO3 transcript was significantly decreased, during the last stages of grain development, in comparison to Sława, a cultivar tolerant to PHS. In case of the CPS3 and VP1 transcripts, the differences between cultivars were especially evident from 17th to 31st day after pollination. In turn, after induction of sprouting within spikes, accumulation of the AAO3 and VP1 mRNA in the Sława grains was lower in comparison to that observed in the Piko grains. Moreover, accumulation of the CPS3 transcript was significantly higher for Piko than for Sława, both in sprouting and non-sprouting grains. According to our knowledge this report provides the first description of the AAO3 and CPS3 expression in the context of PHS, and in the future it would be valuable to correlate this information with the data on the accumulation of ABA and GA3
External validation of the GrazeIn model of pasture dry matter intake and milk yield prediction for cows managed at different calving dates and stocking rates
No full textThe aim was to evaluate the prediction accuracy of pasture dry matter intake (PDMI) and milk yield (MY) predicted by the GrazeIn model using a database representing 124 PDMI measurements at paddock level and 2232 MY measurements at cow level. External validation of the model was conducted using data collected from a trial carried out with Holstein-Friesian cows (n=72) while grazed 28 paddocks and were managed in a 2×2 factorial design by considering two calving dates (CD), with different number of days in milk (DIM), early (E, 29 DIM) vs. middle (M, 167 DIM), and two stocking rates (SR), medium (M, 3.9 cows ha-1) vs. high (H, 4.8 cows ha-1), under a rotational grazing system. Cows were randomly assigned to four grazing scenarios (EM, EH, MM and MH). The mean observed PDMI of the total database was 14.2 kg DM cow-1 day-1 while GrazeIn predicted a mean PDMI for the database of 13.8 kg DM cow-1 day-1. The mean bias was −0.4 kg DM cow-1 day-1. GrazeIn predicted PDMI for the total database with a relative prediction error (RPE) of 10.0% at paddock level. The mean observed MY of the database was 23.2 kg cow-1 day-1 while GrazeIn predicted a MY for the database of 23.1 kg cow-1 day-1. The mean bias was –0.1 kg cow-1 day-1. GrazeIn predicted MY for the total database with a mean RPE of 17.3% at cow level. For the scenarios investigated, GrazeIn predicted PDMI and MY with a low level of error which made it a suitable tool for decision support systems
Plant-conservative agriculture of acid and degraded Raña-grassland enhances diversity of the common soil mites (Oribatida)
No full textThe seminatural prairie of the Raña of Cañamero (Spain) is a degraded and unproductive agrosystem with acid and stony soils, and low coverage of xerophytic grasses. In a project about secondary reconversion of the raña-prairie to a more productive cropland, an experimental field (EF) was established to assess the effect on plot-productivity of the interaction between correction of soil pH (liming) with three cropping systems: a no-tilled and annually fertilized and improved prairies, and a conventionally-tilled forage crop. The EF model of management was designed as plant-conservative, because no herbicide was applied after seeding to preserve the post-emergence of wild herbs and the natural grass diversity of the prairie. Between 2008 and 2012, we analysed the effect of managing factors (initial conventional-tillage, fertilization, liming and cropping) and agricultural predictors (pH, C:N ratio, soil bulk density and herbaceous biomass) on the alpha(α)-diversity of one of the major group of soil animals, the oribatids. In relation to the raña-prairie, all EF-plots improved their soil bulk density (ρs) and herbaceous biomass (t/ha), and enhanced desirable α-diversity values (richness, abundance and community equity). We conclude that the plant-conservative model: i) do not affect statistically the species richness of the prairie; ii) the desirable α-diversity responses are negatively correlated with soil bulk density and positively with herbaceous biomass, and iii) the low input or minimum intervention model, of an initial and conventional till and annual fertilisation, is the threshold and optimal model of agricultural management to improving oribatids diversity of the raña-soil
Effect of space allowance during transport and fasting or non-fasting during lairage on welfare indicators in Merino lambs
No full textA total of 72 male lambs of Merina breed were sampled in a 3×2 factorial design, testing three different space allowances treatment (SA) during transport [0.16 m2/animal (SAL; n=24); 0.20 m2/animal (SAM; n=24) and 0.30 m2/animal (SAH; n=24)] and two lairage treatments (TL) during 18 h previous slaughter [fasting (FAST; n=36) vs feeding (FEED; n=36)] on welfare physiological indicators. After transport, glucose and lactate dehydrogenase (LDH) were highest in SAM group and lowest in SAH one (p<0.05). SAL showed intermediate values for both parameters. SA did not affect the rest of the blood parameters studied. TL-FAST treatment decreased glucose values (p<0.001) while increased LDH (p<0.001). Fasting caused an increase (p<0.05) of Red Blood Cell Count values in SAM group. Feed deprivation did not affect cortisol or adrenaline values. Noradrenaline value was higher (p<0.001) in TL-FAST groups than in TL-FEED. In conclusion, under the conditions of this study, a range of space allowance during transport between 0.16 and 0.30 m2/lamb could be recommended without showing major changes on welfare physiological indicators; and feeding could be more appropriate than fasting during lairage
Carbon dioxide enrichment: a technique to mitigate the negative effects of salinity on the productivity of high value tomatoes
No full textThe present study was conducted to determine the mitigating influence of greenhouse CO2 enrichment on the negative effects of salinity in Mediterranean conditions. Hybrid Raf (cv. Delizia) tomato plants were exposed to two salinity levels of the nutrient solution (5 and 7 dS/m) obtained by adding NaCl, and two CO2 concentrations (350 and 800 μmol/mol) in which CO2 enrichment was applied during the daytime according to a strategy linked to ventilation. Increasing water salinity negatively affected the leaf area index (LAI), the specific leaf area (SLA), the water use efficiency (WUE), the radiation use efficiency (RUE) and dry weight (DW) accumulation resulting in lower marketable yield. The high salinity treatment (7 dS/m) increased fruit firmness (N), total soluble solids content (SSC) and titratable acidity (TA), whereas pH was reduced in the three ripening stages: mature green/breaker (G), turning (T), and pink/light red (P). Also, the increase in electrical conductivity of the nutrient solution led to a general change in intensity of the sensory characteristics of tomato fruits. On the other hand, CO2 enrichment did not affect LAI although SLA was reduced. RUE and DW accumulation were increased resulting in higher marketable yield, through positive effects on fruit number and their average weight. WUE was enhanced by CO2 supply mainly through increased growth and yield. Physical-chemical quality parameters such as fruit firmness, TA and pH were not affected by CO2 enrichment whereas SSC was enhanced. Greenhouse CO2 enrichment did mitigate the negative effect of saline conditions on productivity without compromising organoleptic and sensory fruit quality
Bitter pit in apples: pre- and postharvest factors: A review
No full textBitter pit is a physiological disorder that significantly reduces the quality of apples. Although it has been detected since the beginning of the last century, still there is little known about the mechanism of its occurrence. According to numerous studies, bitter pit is formed as a result of calcium deficiency in the fruit. Some authors cite the high concentration of gibberellins, later in the production season, most probably caused by excessive activity of the roots, as the chief causative factor. Beside Ca, there are several factors that can also contribute to its development, like imbalance among some mineral elements (N, P, K and Mg), cultivar, rootstock, the ratio of vegetative and generative growth, post-harvest treatments and the storage methods. There are some prediction models available that can estimate the risk of bitter pit in apples, but even those are not always reliable. The aim of this review was to encompass the pre and postharvest factors which cause bitter pit and point out the directions for solving this problem
Genetics of drought tolerance at seedling and maturity stages in Zea mays L.
No full textShortage of irrigation water at critical growth stages of maize is limiting its production worldwide. Breeding drought-tolerant cultivars is one possible solution while identification of potential genotypes is crucial for genetic improvement. To assess genetic variation for seedling-stage drought tolerance, we tested 40 inbred lines in a completely randomized design under glasshouse conditions. From these, two contrasting inbred lines were used to develop six basic generations (P1, P2, F1, F2, BC1F1, BC2F2). These populations were then evaluated in a triplicated factorial randomized complete block design under non-stressed and drought-stressed conditions. For statistical analyses, a nested block design was employed to ignore the replication effects. Significant differences (p≤0.01) were recorded among the genotypes for investigated seedling-traits. Absolute values of fresh root length, fresh root weight, and dry root weight lead to select two genotypes, one tolerant (WFTMS) and one susceptible (Q66). Estimates of heritability, genetic advance, and genotypic correlation coefficients were higher and significant for most of the seedling-traits. Generation variance analysis revealed additive gene action. Narrow-sense heritability [F2 ≥ 65; F∞ ≥ 79] revealed the same results. Generation mean analysis signified additive genetic effects in the inheritance of cob girth, non-additive for plant height, grains per ear row and grain yield per plant, and environmental for ear leaf area, cob length, grain rows per ear, biomass per plant, and 100-grain weight under drought-stressed conditions. For conferring drought-tolerance in maize, breeders can adopt the recombinant breeding strategy to pyramid the desirable genes
Evaluation and prioritization of rice production practices and constraints under temperate climatic conditions using Fuzzy Analytical Hierarchy Process (FAHP)
No full textDue to overwhelming complex and vague nature of interactions between multiple factors describing agriculture, Multi-Criteria Decision Making (MCDM) methods are widely used from farm to fork to facilitate systematic and transparent decision support, figure out multiple decision outcomes and equip decision maker with confident decision choices in order to choose best alternative. This research proposes a Fuzzy Analytical Hierarchy Process (FAHP) based decision support to evaluate and prioritize important factors of rice production practices and constraints under temperate climatic conditions and provides estimate of weightings, which measure relative importance of critical factors of the crop under biotic, abiotic, socio-economic and technological settings. The results envisage that flood, drought, water logging, late sali, temperature and rainfall are important constraints. However, regulating transplantation time; maintaining planting density; providing training to the educated farmers; introducing high productive varieties like Shalimar Rice-1 and Jhelum; better management of nutrients, weeds and diseases are most important opportunities to enhance rice production in the region. Therefore, the proposed system supplements farmers with precise decision information about important rice production practices, opportunities and constraints
Assessing diversity among traditional Greek and foreign eggplant cultivars using molecular markers and morphometrical descriptors
No full textEggplant is a widely cultivated vegetable crop of great economic importance. Its long lasting history of domestication, selection and breeding has led to the development of numerous cultivars with variable traits. In the present study, we assessed the diversity levels within and among eleven Greek and foreign cultivars, using 22 morphological descriptors and two different classes of molecular markers (retrotransposon microsatellite amplified polymorphism-REMAP markers and nuclear microsatellites). Our results, in accordance with other studies in the field showed: a) the limited levels of genetic polymorphism within the cultivars; b) the high morphological and genetic divergence existing among them as indicated by the genetic distance values calculated, which could be attributed to selection, inbreeding and bottleneck effects; and c) the lack of concordance among morphological descriptors and molecular markers. Despite these, our analysis showed that the utilization of combinations of markers is an effective method for the characterization of plant material providing also useful diagnostic tools for the identification and authentication of the selected Greek cultivars