Albornoz F.,Institute Investigaciones Agropecuarias INIA |
Lieth J.H.,University of California at Davis
Journal of Plant Nutrition | Year: 2017
Under conditions of limited nutrient supply, plant nutrient uptake is controlled by the external concentration of the ions. Limited information exists about the whole-plant regulation of nutrient uptake when the supply is adequate. To study the relationship between growth rate and carbon dioxide (CO2) assimilation with nutrient uptake, growth chamber experiments were conducted with temperatures ranging from 10 to 35°C at medium (600 µmol m−2 s−1) and high (1200 µmol m−2 s−1) light intensities. Nutrient solution samples were collected every 24 hours and the concentration of ions was analyzed by Inductively coupled plasma -atomic emission spectroscopy (ICP-AES) and nitrate and ammonium (NO3 −/NH4 +) conductivity. Leaf photo-synthesis was measured using a closed gas exchange system and the total amount of CO2 assimilated was calculated from dry weight increases. The daily absorption of NO3 −, Total nitrogen (N), dihydrogen phosphate (H2PO4 −) and potassium (K+) responded linearly to plant growth, while ammonium (NH4 +) and sulfate (SO4 2−) uptake showed a curvilinear response. All the ions studied showed a curvilinear relation with CO2 assimilation. © 2017 Taylor & Francis Group, LLC.
Ramirez-Retamal J.,Austral University of Chile |
Morales R.,Institute Investigaciones Agropecuarias INIA
Chilean Journal of Agricultural Research | Year: 2014
This paper reviews two factors (breed and feed) affecting the carcass and meat quality of sheep. The quality of livestock products has acquired greater importance from the distinct perspectives of the different participants in the agricultural food chain. Consumers, producers and the industry give different levels of importance to the parameters of meat and carcass quality. Nevertheless, all the participants in the meat production chain must ensure quality to improve their competitiveness. The quality of the carcass and meat can be influenced by different factors such as breed and type of feed. The breed can influence weight, yields, and the conformation of the carcass, among other variables, as well as the pH level and the fatty acid composition of the meat, whereas the feed mainly affects carcass conformation and several physicochemical and organoleptic parameters of meat quality such as proximal composition, the fatty acid profile, tenderness and color. Consequently, the effects of breed and feed type should be considered to obtain a quality product that satisfies consumer demand.
Rehner S.A.,U.S. Department of Agriculture |
Minnis A.M.,U.S. Department of Agriculture |
Sung G.-H.,Mushroom |
Luangsa-ard J.J.,National Center for Genetic Engineering and Biotechnology |
And 2 more authors.
Mycologia | Year: 2011
Beauveria is a cosmopolitan anamorphic genus of arthropod pathogens that includes the agronomically important species, B. bassiana and B. brongniartii, which are used as mycoinsecticides for the biological control of pest insects. Recent phylogenetic evidence demonstrates that Beauveria is monophyletic within the Cordycipitaceae (Hypocreales), and both B. bassiana and B. brongniartii have been linked developmentally and phylogenetically to Cordyceps species. Despite recent interest in the genetic diversity and molecular ecology of Beauveria, particularly as it relates to their role as pathogens of insects in natural and agricultural environments, the genus has not received critical taxonomic review for several decades. A multilocus phylogeny of Beauveria based on partial sequences of RPB1, RPB2, TEF and the nuclear intergenic region, Bloc, is presented and used to assess diversity within the genus and to evaluate species concepts and their taxonomic status. B. bassiana and B. brongniartii, both which represent species complexes and which heretofore have lacked type specimens, are redescribed and types are proposed. In addition six new species are described including B. varroae and B. kipukae, which form a biphyletic, morphologically cryptic sister lineage to B. bassiana, B. pseudobassiana, which also is morphologically similar to but phylogenetically distant from B. bassiana, B. asiatica and B. australis, which are sister lineages to B. brongniartii, and B. sungii, an Asian species that is linked to an undetermined species of Cordyceps. The combination B. amorpha is validly published and an epitype is designated. © 2011 by The Mycological Society of America.
Haverkort A.J.,Wageningen University |
Haverkort A.J.,University of Pretoria |
Sandana P.,Institute Investigaciones Agropecuarias INIA |
Kalazich J.,Institute Investigaciones Agropecuarias INIA
Potato Research | Year: 2014
In Chile, potatoes are grown in a wide range of ecological zones and levels of technology resulting in wide ranges of crop management and yields. The aim of the present study was to assess yield gaps, resource use efficiencies and foot-printing in different potato cropping zones between 18 and 53° South considering early and late crops, small and large holdings (>10 ha/year) and ware and seed potato crops. Two mathematical tools were used to generate data for comparisons: the light interception and utilization simulator for potato crops (LINTUL-Potato) to calculate potential yields and water need of each system and the Cool Farm Tool – Potato (CFT) to calculate the amount of CO2 associated with the production of 1 ton of potato. Meteorological data for LINTUL-Potato came from official services, and data needed to complete the CFT came from a survey carried out for the 10 sites yielding amounts of inputs and number of operations, potato yields and planting and harvesting dates. The survey yielded 20 cropping systems with an average yield of 31 t ha−1. Yields were related to daily growth rate and not to the length of the growing season. Considerable variation was found in resource-use efficiency and CO2 emission. It was concluded that large farms show a lower land footprint than small farms due to a higher technological level, but while applying more water and fertilizer, they result in higher water and CO2 footprints. Late crops may fetch higher off-season prices but have higher land, water and CO2 footprints. The most suitable potato production systems are the rain-fed summer crops in the South with the lowest footprints. The highest footprints have the irrigated winter crops in the centre of Chile. The subsistence high altitude Andean crop in the utmost North has the highest land footprint but the lowest CO2 emission. The description, analysis and benchmarking of the potato production systems in Chile allow strategies for improving footprints and profitability and yields information about future investments in research, development and production of the crop. © 2014, EAPR.
Morales R.,Institute Investigaciones Agropecuarias INIA |
Aguiar A.P.S.,Institute Investigaciones Agropecuarias INIA |
Subiabre I.,Institute Investigaciones Agropecuarias INIA |
Realini C.E.,IRTA - Institute of Agricultural-Alimentary Research and Technology
Food Quality and Preference | Year: 2013
Beef acceptability and consumer expectations generated with production systems and beef marbling were evaluated in two major Chilean cities. A panel of 204 consumers from Osorno and Santiago rated beef acceptability from four treatments (low or high marbling. ×. grazing or feedlot) in a blind condition, and then with information about marbling and production systems. In addition, consumer expectations induced by the information were evaluated. Three groups of consumers, 'lean beef lovers' (25.5%), 'high expectation consumers' (53.4%) and 'grass-fed beef lovers' (21.1%), were identified based on their expected acceptability. Information about the marbling level and production systems generated positive expectations and increased acceptability of beef with low marbling levels and beef from grazing animals. Results from this study have important implications for the development of beef marketing strategies in the Chilean market. © 2013 Elsevier Ltd.
Carrasco-Rios L.,University of Tarapacá |
Pinto M.,Institute Investigaciones Agropecuarias INIA
Chilean Journal of Agricultural Research | Year: 2014
Salinity is an important problem to crop production; affecting photosynthesis process which favors the production of reactive oxygen species. Plants have generated adaptation strategies to prevent oxidative damage caused by salinity. In this study we evaluated the effect of salinity on lipid peroxidation and antioxidant enzymes in leaves of corn (Zea mays L.) plants 'Lluteño' (adapted to salinity) and 'Jubilee' (improved variety). 'Lluteño' is the only one corn capable to prosper in the Valley of Lluta under saline conditions (EC = 9.1 dS m-1) and the most widely cultivated crop in terms of area in the desert of northern Chile. Plants of 21 d old were subjected for 15 d to two saline treatments: 50 and 100 mM NaCl. Salinity caused a significant reduction in plant biomass, ca. 65% in 'Jubilee' and 20% in 'Lluteño' (P ≤ 0.05). The biomass reduction and oxidative damage to cell membranes caused by the generation of peroxides was significantly less in 'Lluteño'. The activity of superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX), and ascorbate peroxidase (APX) in 'Lluteño' was significantly greater than in 'Jubilee' in all treatments, while glutathione reductase (GR) had greater activity in 'Jubilee'. However, most enzymes studied were adversely affected by salinity compared to the control. These results indicate that tolerance to salinity exhibited by 'Lluteño' should in part due to the high activity that exhibit antioxidant enzymes compared to 'Jubilee'.
Inostroza L.,Institute Investigaciones Agropecuarias INIA |
Acuna H.,Institute Investigaciones Agropecuarias INIA
Plant Breeding | Year: 2010
Water use efficiency (WUE) of nine naturalized white clover (Trifolium repens L.) populations was evaluated to select parental genotypes for future breeding programmes and to identify associated physiological traits that could be used as selection criteria. A greenhouse experiment was carried out during the spring of 2007 in Chillán, Chile (36°p03'S, 72°07'W). The nine naturalized populations plus two controls were planted in pots containing soil as substrate. The plants were grown under two soil water treatments: with water stress (-1 MPa) and without water stress (-0.01 MPa). The experiment was arranged in a randomized complete block design with three replicates. Transpirated water (T) was recorded daily by weighing the pots, shoot DM (leaves + petioles + stolons) production was measured and WUE was calculated (shoot DM/T). Stomatal conductance (gs), chlorophyll content, relative water content, leaf 13C isotopic discrimination, canopy temperature and stolon water potential were also evaluated. The WUE varied significantly (P = 0.05) among populations and increased under drought conditions because of gs reduction. A high WUE was associated with populations that had a low leaf area DM investment and high stolon DM investment. © 2010 Blackwell Verlag GmbH.
Herrera G.,Institute Investigaciones Agropecuarias INIA
Chilean Journal of Agricultural Research | Year: 2013
Sharka disease, which is caused by Plum pox virus (PPV), is one of the most serious diseases affecting stone fruit trees around the world. Identified in Bulgaria in 1931, it was restricted to the European continent until 1992 when the virus was identified in Chile. It was subsequently verified in the USA, Canada, and Argentina. After 20 years since first detecting PPV in Chile, it seems clear that the disease cannot be eradicated in spite of various measures. Considering the seriousness of this problem for the domestic industry, a series of studies have been conducted to determine the distribution and degree of transmission of the disease, its biological and molecular characterization and epidemiological aspects, etc. The available information has allowed national phytosanitary control agencies to take steps to decrease the effects of the virus. However, there is a lack of data with respect to epidemiological factors for a more accurate understanding of the performance of the virus under Chilean conditions.
Hirzel J.,Institute Investigaciones Agropecuarias INIA |
Matus I.,Institute Investigaciones Agropecuarias INIA
Chilean Journal of Agricultural Research | Year: 2013
Agronomic practices, climatic variables, and soil conditions are key factors in crop productivity. Although the effects of soil chemical properties and water and agronomic crop management are known, there is little information about effective soil depth and its influence on crop productivity. Since most crop fertilization systems are based on the productive potential associated with climatic conditions and chemical properties of the first 20 cm of soil depth, the objective of this study was to determine the importance of effective depth in terms of increasing fertilization rates on durum wheat (Triticum turgidum L. var. durum) productivity. Two experiments were conducted in the 2006-2007 season in the Santa Rosa Experimental Station (71o54' S, 36o31' W, 220 m a.s.l.) of the Instituto de Investigaciones Agropecuarias (INIA) located in south central Chile. We used the hard wheat cvs. Llareta-INIA and Corcolén-INIA because both respond differently to soil physicochemical properties. Each cultivar was sown in sectors with different depths: 1) 0.45 m depth, silt loam on river material and 2) 1.0 m depth, loam on deep sediments. Fertilization was: 1) control without fertilization, 2) basal fertilization (BF) based on P, K, Ca, Mg, S, B, and Zn plus 90 kg N ha-1, and 3) BF plus 210 kg N ha-1. Grain yield, plant height, and number of stems m-2 were positively affected by increasing depth of soil profile. The increasing fertilization rate affected grain yield and plant height. Grain yield for cv. Corcolén-INIA had a greater response than cv. Llareta-INIA when soil depth was increased.
Method For The Extraction Of Furan Derivative Compounds From Seeds Of Hass Avocado (Persea Americana Mill) At Low Temperature And Their Use As Repellents And Miticides Against Tetranychus Urticae, Tetranychus Cinnabarinus, Oligonychus Yothersi, Panonychus Citri, And Brevipalpus Chilensis.
Institute Investigaciones Agropecuarias Inia | Date: 2014-06-20
This invention relates to the extraction and use of bioactive compounds from avocado seeds (var. Hass; Persea americana Mill) at room temperature. The extraction was performed with dichloromethane as a solvent using a simple diffusion mechanism within pressed avocado seeds. The extracted compounds were identified as furan derivative structures and fragments derived thereof that exhibited repellent and miticide activity against mite species of economic interest: Tetranychus urticae, Tetranychus cinnabarinus, Oligonychus yothersi, Panonychus citri, and Brevipalpus chilensis. The compounds obtained have the general structure of a disubstituted furan, as illustrated in FIG. 1, and the fragments thereof are derived from mono-substituted furans and from side-chain fragments. The utility of these compounds as repellents was determined over a 48-hour period, and their function as miticides was evaluated for 24 hours after application.