Scientific Journals of INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria)
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Effect of corn replacement with graded levels of wheat screening and enzyme supplementation on performance, blood lipids, viscosity and jejunal histomorphology of finisher broilers
Get PDFAn experiment was carried out to study the effect of corn replacement with five levels of wheat screening (0, 150, 300, 450 and 600 g/kg of diet) with (0.5 g/kg of diet) or without xylanase-glucanase enzyme on performance, blood lipids, viscosity and jejunal histomorphology of finisher broilers (25-42 days of age). Five hundred day-old Ross-308 male broiler chicks were fed by a standard commercial diet up to 24 days of age, then randomly assigned to 10 diets. Each diet was fed to five groups of ten chicks each. There was not significant differences in body weight gain (BWG), feed intake, and feed conversion ratio of birds fed with different levels of wheat screening (WS), whereas enzyme increased (p<0.05) BWG. Different levels of WS and enzyme did not have a significant effect on relative weights of carcass, breast, thigh, and abdominal fat of broilers. Relative weights of gizzard, pancreas, small and large intestine, and relative length of jejunum and jejunal and ileal viscosity were increased (p<0.05) by WS, while were decreased (p<0.05) by enzyme. The serum cholesterol level decreased (p<0.05) by increasing levels of WS. Jejunal histomorphological observations showed (p<0.05) shorter and thicker villus and lower crypt depth by increasing levels of WS, while addition of enzyme to the diets, affected (p<0.05) reversely to these parameters. The results showed that the addition of wheat screening up to an inclusion level of 600 g/kg of diet had no adverse effect on broiler performance in the finisher (25-42 d) phases whereas decreased serum cholesterol levels, increased viscosity and villus atrophy. The dietary administration of exogenous enzyme improved performance parameters and decreased viscosity and villus atrophy of broiler jejunum
Genetic relationships between interspecific lines derived from Oryza glaberrima and Oryza sativa crosses using microsatellites and agro-morphological markers
Get PDFNew Rice(s) for Africa (NERICA) are high yielding rice varieties mostly cultivated in Sub-Saharan Africa and developed by the Africa Rice Center. This study is aimed at investigating the proportion of introgression of parental genomic contribution of 60 lowland NERICA varieties and establishment of molecular profiling. Agro-morphological data from 17 characteristics was recorded and significant (p<0.05) to high significant (p<0.0001) differences were obtained with leaf length and width, plant height at maturity, days to heading, maturity, primary and secondary branching of panicles, and grain width and grain thickness. A total of 114 microsatellite polymorphic markers covering 2183.13 cM of the rice genome showed the proportions of alleles introgressed from the donor parent (Oryza glaberrima) into 52 lowland NERICA lines (TOG5681 and IR64) as follows: 11% for BC2, 6.07% for BC3, and 7.55% for BC4. The introgression proportions for the eight remaining lowland NERICA lines derived from other crosses ranged from 5.5 to 11.3%. The proportion recorded with the recurrent parent was 83.99%. The highest introgression proportions of the O. glaberrima allele for all 60 lowland NERICA lines were found on chromosomes 2, 6 and 12 (TOG5681/IR64) and on chromosome 3 with NERIC-L-29 (TOG5681/IR1529-680-3-2). Multivariate analyses performed using an association of agro-morphological and molecular data revealed two major groups according to the distribution of the lowland NERICAs including the lowland NERICAs released were found in cluster 1 of the dendrogram. Genetic and genomic studies, QTL identification and analysis using agro-morphologically significant traits revealed should be used to develop mega-varieties adapted in rice growth conditions in Sub-Saharan Africa
Use of organic mulch to enhance water-use efficiency and peach production under limiting soil conditions in a three-year-old orchard
Get PDFMulching techniques have emerged in recent years to overcome soil constraints and improve fruit tree productivity. The object of this study was to evaluate the effects of a low-cost organic mulch application in a newly planted peach orchard under a ridge planting system. Three treatments were performed in 12 elementary plots using a randomized complete block design. The orchard was drip-irrigated. Mulch was applied in two treatments, which differed in fertigation (none vs. multi-nutrient fertigation), while the third treatment did not include either mulch or fertigation and served as the control. Treatments were compared in terms of their effects on the physical properties of the soil, crop response, and water-use efficiency. Mulch treatments did not alter the soil bulk density. However, the mulch significantly (p=0.0004) increased the water infiltration rate (2.21 mm/h vs. 121 mm/h), which is a key issue when working in high frequency irrigation systems under soil limiting conditions. Similarly, mulched treatments showed a more favorable water status both in the second and the third year, which was translated in a better crop response. Thus, mulched treatments recorded higher yields both in the second (+155%, p=0.0005) and the third year (+53%, p=0.0007) of the experiment. Water use efficiency (WUEagr) was higher in the mulch treatments (+50% in average, p=0.0007) than in the control in the third year of the study. On the basis of our results, we propose that organic-mulching techniques should be considered as a beneficial practice to apply in fruit-trees production under limiting soil conditions
Comparison of the growth and biomass production of Miscanthus sinensis, Miscanthus floridulus and Saccharum arundinaceum
Get PDFMiscanthus and Saccharum are considered excellent candidates for bioenergy feedstock production. A field experiment was conducted in Zhejiang province of China to characterize the phenotypic differences in three species, two of Miscanthus (M. sinensis and M. floridulus) and one of Saccharum (S. arundinaceum), each with two accessions collected from China. Agronomical traits, including plant height, culm number, tuft diameter and culm diameter, were monitored monthly for the first 3 years of growth. For each year of trail, flowering time was observed and biomass yield was harvested. M. floridulus produced a superior biomass yield with increasing plant age associated with higher yields (4.18, 24.16 and 29.01 t dry matter/hain November of years one to three, respectively). Higher culm diameter, plant height and tuft diameter values were observed for M. floridulus when compared to the other species. Biomass yield was positively correlated to tuft diameter, culm diameter, culm number and negatively to flowering time, but it showed no correlation with plant height. Tuft diameter and culm diameter could be suitable indicators in the selection of accessions for crop yield at the yield-building phase. Studies of the primary colonizers of Miscanthus and Saccharum in their original location may be of interest from the perspective of bioenergy germplasm resource collection
Organic amendments conditions on the control of Fusarium crown and root rot of asparagus caused by three Fusarium spp.
Get PDFFusarium oxysporum (Fo), F. proliferatum (Fp) and F. solani (Fs) are causal agents associated with roots of asparagus affected by crown and root rot, a disease inflicting serious losses worldwide. The propagule viability of Fusarium spp. was determined on substrate artificially infested with Fo5, Fp3 or Fs2 isolates, amended with either poultry manure (PM), its pellet (PPM), or olive residue compost (ORC) and, thereafter, incubated at 30 or 35°C for different periods. Inoculum viability was significantly affected by these organic amendments (OAs) in combination with temperature and incubation period. The greatest reduction in viability of Fo5 and Fs2 occurred with PPM and loss of viability achieved was higher at 35°C than at 30ºC, and longer incubation period (45 days). However, the viability of Fp3 did not decrease greatly in most of the treatments, as compared to the infested and un-amended control, when incubated at 30ºC. After incubation, seedlings of asparagus `Grande´ were transplanted into pots containing substrates infested with the different species of Fusarium. After three months in greenhouse, symptoms severity in roots showed highly significant decreases, but Fp3 caused lower severity than Fo5 and Fs2. Severity reduction was particularly high at 30ºC (by 15 days incubation for Fs2 and by 30-45 days for Fo5), after PPM treatment, as well as PM-2% for Fo5 and Fs2 incubated during 30 and 45 days at both temperatures, and with ORC (15-30 days incubation). Moreover, assessment of plants fresh weight showed significantly high increases in Fo5 and Fs2, with some rates of the three OAs tested, depending on incubation period and temperature
Use of geophysical survey as a predictor of the edaphic properties variability in soils used for livestock production
Get PDFThe spatial variability in soils used for livestock production (i.e. Natraquoll and Natraqualf) at farm and paddock scale is usually very high. Understanding this spatial variation within a field is the first step for site-specific crop management. For this reason, we evaluated whether apparent electrical conductivity (ECa), a widely used proximal soil sensing technology, is a potential estimator of the edaphic variability in these types of soils. ECa and elevation data were collected in a paddock of 16 ha. Elevation was negatively associated with ECa. Geo-referenced soil samples were collected and analyzed for soil organic matter (OM) content, pH, the saturation extract electrical conductivity (ECext), available phosphorous (P), and anaerobically incubated Nitrogen (Nan). Relationships between soil properties and ECa were analyzed using regression analysis, principal components analysis (PCA), and stepwise regression. Principal components (PC) and the PC-stepwise were used to determine which soil properties have an important influence on ECa. In this experiment elevation was negatively associated with ECa. The data showed that pH, OM, and ECext exhibited a high correlation with ECa (R2=0.76; 0.70 and 0.65, respectively). Whereas P and Nan showed a lower correlation (R2=0.54 and 0.11 respectively). The model resulting from the PC-stepwise regression analysis explained slightly more than 69% of the total variation of the measured ECa, only retaining PC1. Therefore, ECext, pH and OM were considered key latent variables because they substantially influence the relationship between the PC1 and the ECa (loading factors>0.4). Results showed that ECa is associated with the spatial distribution of some important soil properties. Thus, ECa can be used as a support tool to implement site-specific management in soils for livestock use
Evaluation of Forest Dynamics Focusing on Various Minimum Harvesting Ages in Multi-Purpose Forest Management Planning
Get PDFAim of study: Exploring the potential effects of various forest management strategies on the ability of forest ecosystems to sequester carbon and produce water has become of great concern among forest researchers. The main purpose of this study is to evaluate the effects of management strategies with different minimum harvesting ages on the amount and monetary worth of carbon, water and timber values.Area of study: The study was performed in the Yalnızçam planning unit located on the northeastern part of Turkey.Material and Methods: A forest management model with linear programming (LP) was developed to determine the effects of various minimum harvesting ages. Twenty-four different management strategies were developed to maximize the economic Net Present Value (NPV) of timber, water and carbon values in addition to their absolute quantities over time. Amount and NPV of forest values and ending inventory with different minimum harvesting ages were used as performance indicators to assess and thus understand forest dynamics.Main results: Amount and NPV of timber and carbon generally decreased with extended minimum harvesting ages. However, similar trends were not observed for water production values. The results pointed out that the performance of a management strategy depends highly on the development of a management strategy and the initial forest structure aside from the growth rate.Research highlights: Minimum harvesting ages affect forest outputs under the same objectives and constraints. Performance of a management strategy highly depends on initial age class structure in addition to the contents of a management strategy.Keywords: linear programming; forest management planning; carbon sequestration; water production; forest dynamics
Changes in climate-growth relationships and IADF formation over time of pine species (Pinus halepensis, P. pinaster and P. sylvestris) in Mediterranean environments
Get PDFBackground: The Mediterranean basin has experienced an increase in the mean annual temperature, a decrease in the mean annual precipitation, and an increase in the frequency of severe drought periods during the second half of the 20th century. However, winter and spring precipitation has increased and summer precipitation has decreased in the western Mediterranean region. Aim of the study:The objectives of the present study were: i) to compare changes in climate-growth relationships over time for Pinus halepensis, P. pinaster and P. sylvestris in Spain ii) to quantify the presence of intra-annual density fluctuations (IADFs) on the three species, and iii) to define the associated climatic variables. Area of study: 26 sampling sites (8 P. halepensis sites, 8 P. pinaster sites and 10 P. sylvestris sites) were selected in their distribution area in Spain. Main results:Precipitation is the main factor influencing growth and IADF occurrence in the three species. Wet periods during previous winter and spring induced higher growth rates on P. halepensis and P. pinaster, while P. sylvestris was mostly influenced by summer precipitation. However, the influence of these climatic variables on the growth of these species changed over the studied period. The increase of winter and spring precipitation combined with increasingly harsh summer climatic conditions in the second half of the 20th century may have enhanced the importance of precipitation at the beginning of the growing season on the growth of species subject to higher summer drought stress (P. halepensis and P. pinaster) and increased IADF occurrence. Research highlights: Besides reflecting changes in the environmental conditions during the growing season, the inclusion of IADF detection in chronologies adds new information to ring-width chronologies, thereby improving its quality.Key words: Aleppo pine; maritime pine; scots pine; dendroclimatology, IADFs.Abbreviations used: IADF: Intra-annual density fluctuation; AIC: Akaike information criterion; ROC: Receiver operating characteristic
Response of European yews to climate change: a review
Get PDFAim of study: Being the longest-lived of all European trees, capable of living significantly over 2,000 years, yew is highly likely to be negatively affected by climate change; this paper explores the changes in distribution and abundance. Main results: Yew is unlikely to migrate north due to its slow rate of invasion, its disjunct soil needs and an inability to cope with the expected rate of climate change. It will, however, retreat from the southern end of its range in Spain due to increased evapotranspiration allied to reduced rainfall. In the south, increased drought will be exacerbated by extreme drought and increased fire frequency. In drier areas at the northern edge of its range, yew will decline where growing on well-drained limestone outcrops with little shelter from the sun (increased evaporation) and reduced water availability due to limited root spread. On wetter northern sites, yew should find better climatic conditions but will be slow to invade new areas due to poorer reproduction affected by reduced pollen production, population fragmentation and limited seed movement. Overall, without our intervention, yew will survive by inertia in the short-term but eventual become extinct in most areas. Of equal concern will be the loss of old veteran individuals and associated biodiversity. Research highlights: There is an urgent need for interventionist management for both old and young trees, relieving the stress on old veteran trees, and planting and maintaining seedlings through vulnerable young age. A list of management priorities is given.Keywords: Yew; Taxus baccata; Temperature; Precipitation; Seedlings; Bioclimate envelope; Species range
Estimation of Acacia melanoxylon unbleached Kraft pulp brightness by NIR spectroscopy
Get PDFAim of the study: The ability of NIR spectroscopy for predicting the ISO brightness was studied on unbleached Kraft pulps of Acacia melanoxylon R. Br.Area of study: Sites covering littoral north, mid interior north and centre interior of Portugal.Materials and methods: The samples were Kraft pulped in standard identical conditions targeted to a kappa number of 15. A Near Infrared (NIR) partial least squares regression (PLSR) model was developed for the ISO brightness prediction using 75 pulp samples with a variation range of 18.9 to 47.9 %.Main results: Very good correlations between NIR spectra and ISO brightness were obtained. Ten methods were used for PLS analysis (cross validation with 48 samples), and a test set validation was made with 27 samples. The 1stDer pre-processed spectra coupling two wavenumber ranges from 9404 to 7498 cm-1 and 4605 to 4243 cm-1 allowed the best model with a root mean square error of ISO brightness prediction of 0.5 % (RMSEP), a r2 of 99.5 % with a RPD of 14.7.Research highlights: According to AACC Method 39-00, the present model is sufficiently accurate to be used for process control (RPD ≥ 8).Key words: Acacia melanoxylon; unbleached Kraft pulps; ISO Brightness; NIR; RPD