Scientific Journals of INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria)
Not a member yet
3042 research outputs found
Sort by
Short communication: Effect of mycoviruses on growth, spore germination and pathogenicity of the fungus Fusarium circinatum
Get PDFAim of the study: To assess the impact on two mycoviruses recently described in F. circinatum mitovirus 1, and 2-2 (FcMV1 and FcMV2-2) on i) mycelial growth, ii) spore germination and iii) relative necrosis.Material and methods: Fourteen monosporic strains of F. circinatum (one of each pair infected with mycoviruses and the other without them) of the pathogen with and without viruses were selected for the assay. The statistical analysis, were a linear mixed model of analysis of variance considering one between-subjects factor (isolate) and one within-subjects factor with four levels (1=without viruses, 2=only virus FcMV1, 3=only virus FcMV2-2 and 4=both viruses).Main results: Colony growth rates of F. circinatum isolates were significantly reduced in presence of mycoviruses (p=0.002). The spore germination was also reduced in the F. circinatum isolates containing mycovirus as compared to mycovirus-free isolates (p<0.001). No significant differences in lesion lengths caused by F. circinatum were found in relation to the presence/absence of mycovirus (p<0.61).Research highlights: Reduction of the percentage of spore germination in the isolates of F. circinatum with mycovirus infections, as compared to free isolates, provides indications of reduction of metabolic activity and plant physiology are discussed. The lack of significant differences found in the length of the lesions caused by F. circinatum with respect to the presence/absence of mycovirus, indicates that further studies with a larger number of variables are required.
Fire response of the endangered Pinus culminicola stands after 18 years in Cerro El Potosí, northeast Mexico
Get PDFAim of the study: To analyze the impact of the 1998 wildfire on dwarf pine (Pinus culminicola) population stands 18 years after the fire.Area of study: Cerro el Potosí, Nuevo León (México)Material and methods: We measured regeneration, biovolume of individuals, diversity and species composition in unburned and burned plots randomly selected in the area.Main results: Recovery was very slow, with limited dense natural regeneration and very slow growth. Significant differences between control and burned plots were found with respect to regeneration, species composition, evenness and soil nutrients, suggesting that fire could promote natural regeneration and biodiversity in these communities.Research highlights: Management efforts are necessary to maintain a natural fire regime and ensure grazing exclusion in order to favor the conservation of the community dominated by this rare species P. culminicola
Susceptibility of eucalyptus species and hybrids to the gall wasp Leptocybe invasa (Hymenoptera: Eulophidae) in northern Misiones, Argentina
Get PDFAim of study: To analyze the susceptibility of Eucalyptus and hybrids species to Leptocybe invasa through field assays.Area of study: The north of the Argentine province of Misiones (Colonia Delicia). Material and methods: A total of 11 Eucalyptus species and 2 hybrids were surveyed for damage and severity of L. invasa infestation. Six evaluations were made during an annual period.Main results: The susceptibility ranking to L. invasa from highest to lowest was E. tereticornis > E. propinqua > E. dunni > E. camaldulensis > E. grandis > E. major > E. longistrata >E. grandis × E. camaldulensis. However, E. moluccana, E. urophylla × E. grandis and E. urophylla were tolerant to L. invasa.Research highlights: This study suggests that in Misiones, E. tereticornis is the most sensible eucalyptus species to gall wasp attack, whereas other species and hybrids presented low damage levels or tolerance to L. invasa region
Estimating forest uniformity in Eucalyptus spp. and Pinus taeda L. stands using field measurements and structure from motion point clouds generated from unmanned aerial vehicle (UAV) data collection
Get PDFAim of study: In this study we applied 3D point clouds generated by images obtained from an Unmanned Aerial Vehicle (UAV) to evaluate the uniformity of young forest stands.Area of study: Two commercial forest stands were selected, with two plots each. The forest species studied were Eucalyptus spp. and Pinus taeda L. and the trees had an age of 1.5 years.Material and methods: The individual trees were detected based on watershed segmentation and local maxima, using the spectral values stored in the point cloud. After the tree detection, the heights were calculated using two approaches, in the first one using the Digital Surface Model (DSM) and a Digital Terrain Model, and in the second using only the DSM. We used the UAV-derived heights to estimate an uniformity index.Main results: The trees were detected with a maximum 6% of error. However, the height was underestimated in all cases, in an average of 1 and 0.7 m for Pinus and Eucalyptus stands. We proposed to use the models built herein to estimate tree height, but the regression models did not explain the variably within the data satisfactorily. Therefore, the uniformity index calculated using the direct UAV-height values presented results close to the field inventory, reaching better results when using the second height approach (error ranging 2.8-7.8%).Research highlights: The uniformity index using the UAV-derived height from the proposed methods was close to the values obtained in field. We noted the potential for using UAV imagery in forest monitoring
Developing a quantitative hunting regionalization framework: A new game management tool
Get PDFAim of study: Monitoring and control the hunting activity is primordial to guarantee its sustainability. However, the governmental agencies responsible to manage hunting commonly are unable to adequately do this job because the thousands of small private hunting states, associated exclusively by political-administrative criteria. In this work, we provided a new management tool through the establishment of a hunting regions system.Area of study: Castilla-La Mancha region, central Spain.Material and methods: We used a two-stage procedure to establish the environmental units than, afterwards, were characterized on a set of hunting variables.Main results: We generate a hunting regionalization with 12 hunting regions and proposed regional hunting yields for each of the hunting regions.Research highlights: The use of hunting regions will permit to define the game management practices more appropriately on a large scale, but also, will facilitate the tasks of assessment, management and monitoring of game of the number hunting states included in each hunting region.Aim of study: Monitoring and control the hunting activity is primordial to guarantee its sustainability. However, the governmental agencies responsible to manage hunting commonly are unable to adequately do this job because the thousands of small private hunting states, associated exclusively by political-administrative criteria. In this work, we provide a new management tool through the establishment of a hunting regions system.Area of study: This study was conducted at the Castilla-La Mancha region, in central Spain.Material and methods: We used a two-stage procedure to establish the environmental units than, afterwards, were characterized on a set of hunting variables.Main results: We generate a hunting regionalization with 12 hunting regions and proposed a regional hunting yields for each of the hunting regions.Research highlights: The use of hunting regions will permit to define the game management practices more appropriately on a large scale, but also, will facilitate the tasks of assessment, management and monitoring of game of the number hunting states included in each hunting regio
Use of LiDAR data during multi-annual periods for estimating forestry variables
Get PDFAim of study: To test the use of LiDAR data from a single acquisition in order to estimate volume overbark variations ina 5-yr period of Pinus radiata D. Don.Area of study: Province of Bizkaia in the Autonomous Community of the Basque Country (Spain).Material and methods: Two field plot measurements were made in 2011 and 2015 and two wood volume models (one for each year) were fitted using the metric variables of the 2012 LiDAR points cloud. The models were applied to a 26.59 m raster covering the study area and the increase in volume at each pixel was calculated by subtraction.Main results: The increase in estimated wood volume, when added to the volume of timber extracted in the area during the 5-yr period under consideration, yielded an average increase of 13.74 m3 ha-1 yr-1, which corresponds to the average growth of the P. radiata in that area. The harvest area estimated using this procedure largely coincides with the actual harvest area in the same period. The value of R2 (85%) of the wood volume model for 2011 is similar to that obtained in other studies. However, as expected, the one obtained for the wood volume model for 2015 (80%) is significantly lower.Research highlights: The increase in wood volume can be estimated using a single LiDAR flight and field data from the 5-yr period provided that data from plots subjected to this kind of harvest is included in the models
The effect of coarse-droplet spraying with double flat fan air induction nozzle and spray volume adjustment model on the efficiency of fungicides and residues in processing tomato
Get PDFThe study was conducted for the purpose of improving the application of fungicides against potato late blight (Phytophthora infestans (Mont.) de Bary) (PLB) in processing tomato. The usability of coarse spray quality with double flat fan air induction IDKT12003 nozzle and the impact of fixed and variable spray volume and adjuvants during alternate application of azoxystrobin and chlorothalonil were analysed on the basis of plant infestation and fungicide residues. The variable spray volume was calculated based on the number of leaves on a plant. The study was conducted during three vegetation seasons. Spraying of plants with significantly flattened canopies during the peak of the fructification season using an IDKT12003 nozzle was as effective as in the case of fine spraying performed with an XR11003 nozzle and facilitated the increase of fungicides residue. In the case of plants with high-spreading canopy at the beginning of fructification, XR11003 nozzle favoured the reduction of PLB infestation. Both spray volume adjustment systems enabled the same level of protection of tomato against PLB, which could result from alternate application of systemic and contact fungicides. Polyalkyleneoxide modified heptamethyltrisiloxane adjuvant, which causes siginificant increase in wetting and droplet spreading, facilitated the reduction of tomato PLB infestation during the application of fungicides using an IDKT12003 nozzle
Arthropod communities within the olive canopy as bioindicators of different management systems
Get PDFArthropods, within the olive tree canopy, which can act as bioindicators of different management systems (conventional, integrated and organic), were collected in costal Croatia during 2007-2009. The aim of the research was to determine the arthropod orders present in each of the observed olive groves, to identify the number of individuals in each order, and to set potential bioindicators of different management systems. In order to do that, arthropods were collected from the olive canopies at three locations (Supetar, Kaštel Stari and Duilovo). After the samples were sorted according to orders, and determined according to arthropods determination keys. Olive groves were characterised by the same growth conditions and environment, with differences in agricultural management systems. In this investigation, 7882 arthropods were collected, belonging to 17 orders. It was found that Diptera, Heteroptera and other Hemiptera individuals, excluded Cicadidae and Psyllidae family individuals, could be defined as potential bioindicators of olive groves under different management systems. The number of Araneae and Coleoptera individuals significantly differed in all researched olive groves. So, these orders can be considered as bioindicators of different management systems. The knowledge obtained in this research can potentially be exploited in olive production in the future. Obtained results represent an important contribution to the inventory of arthropods in olive canopy. Also, this research significantly improves understanding of both harmful and beneficial entomofauna in olive groves and consequently contributes to better understanding of the total entomofauna in Croatia