Authors
| Filter results15 paper(s) found. |
|---|
1. Variable Rate Application Of Potassium Fertilizer For Soybean Crop Growth In A No-till SystemVariable rate application of fertilizer has the potential to improve nutrient use efficiency, improve economic returns, and reduce negative environmental impacts. The objective of this study was to evaluate the variable rate application of potassium fertilizer to soybean crop in a no-till system. The study was conducted on a 13-ha soybean grain field in Carambeí, State of Paraná, Brazil in a Typic Hapludox. The area has been under no-tillage for more than 10 years growing grains... A.C. Bernardi, L.M. Gimenez, C.A. Silva, P.L. Machado |
2. Evaluation Of A Controlled Release N-P Fertilizer Using A Modified Drill For Variable Rate FertilizationBase NP or NPK fertilization is a common practice in cereal production in Chile. Usually, a physical NPK blend is band applied with the seed at planting with the drill. Normal fertilizer rates vary from 400 to 500 kg ha-1; however, there is a tendency in the market to move from physical blend towards chemical blends (monogranule) and, more recently, to controlled release fertilizers (CRF). The CRF are usually recommended at very low rates, varying from 70 to 120 kg ha-1, however this rates are... R.A. Ortega, J.F. Reyes, W. Esquivel, J. Orellana |
3. Spatial Variability Of Spikelet Sterility In Temperate Rice In ChileSpikelet sterility (blanking) causes large economic losses to rice farmers in Chile. The most common varieties are susceptible to low air and water temperatures during pollen formation and flowering, which is the main responsible for the large year to year variation observed in terms of blanking and, therefore, of grain yield. The present work had for objective to study the spatial variability of spikelet sterility within two rice fields, during two consecutive seasons, and relate it to water... R.A. Ortega, D.E. Del solar, E. Acevedo |
4. Use of Cluster Regression for Yield Prediction in Wine Grape@font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }div.Section1 { page: Section1;... L.E. Acosta, L.A. Jara, R.A. Ortega |
5. Melon Classification and Segementation Using Low Cost Remote Sensing Data DronesObject recognition represents currently one of the most developing and challenging areas of the Computer Vision. This work presents a systematic study of various relevant parameters and approaches allowing semi-automatic or automatic object detection, applied onto a study case of melons on the field to be counted. In addition it is of a cardinal interest to obtain the quantitative information about performance of the algorithm in terms of metrics the suitability whereof is determined by the final... T. Zhao, Y. Chen, J. Franzen, J. Gonzalez, Q. Yang |
6. Use of the Active Sensor Optrx to Measure Canopy Changes to Evaluate Foliar Treatments and to Identify Soil Quality in Table GrapeTable Grape (Vitis vinifera L.) is the main exporting horticultural crop in Chile, with the country being one of the top exporters at the world level. Commonly, grape producers perform trials of different commercial products which are not evaluated in an objective way. On the other hand they do not have the tools to easily identify areas within the field that may have some limiting factor. The use of active ground sensors that pass under the canopy several times during the season may... R.A. Ortega, M.M. Martinez, H.P. Poblete |
7. AGTECH CHILE: an Outreach and Technology Transfer Platform for Closing Gaps in Emerging Chilean Precision Agriculture CompaniesPrecision agriculture (PA) is being developed in Chile since 1997. Today there are approximately 20 companies providing products and services in PA at different levels. Most of them are young entrepreneurships which have important knowledge gaps, particularly on technology basis and data management to transform them into useful information. In order to help closing some of the gaps, and contributing to the development of an innovation ecosystem, an extension proposal was developed, which... R.A. Ortega, P. Trebilcock |
8. Almond Canopy Detection and Segmentation Using Remote Sensing Data DronesThe development of Unmanned Aerial System (UAV) makes it possible to take high resolution images of trees easily. These images could help better manage the orchard. However, more research is necessary to extract useful information from these images. For example, irrigation schedule and yield prediction both rely on accurate measurement of canopy size. In this paper, a workflow is proposed to count trees and measure the canopy size of each individual tree. The performances of three different methods... T. Zhao, M. Cisneros, Y. Chen, Q. Yang, Y. Zhang |
9. Data Fusion of Imagery from Different Satellites for Global and Daily Crop MonitoringSatellite-based Crop Monitoring is an important tool for decision making of irrigation, fertilization, crop protection, damage assessment and more. To allow crop monitoring worldwide, on a daily basis, data fusion of images taken by different satellites is required. So far, most researches on data fusion focus on retrospective analysis, while advanced crop monitoring capabilities mandate the use of data in real time mode. Therefore, our project goals were: (1) to build a data-fusion online system... O. Beeri, R. Pelta, S. Mey-tal, J. Raz |
10. Detecting Variability in Plant Water Potential with Multi-Spectral Satellite ImageryIrrigation Intelligence is a practice of precise irrigation, with the goal of providing crops with the right amount of water, at the right time, for optimized yield. One of the ways to achieve that, on a global scale, is to utilize Landsat-8 and Sentinel-2 images, providing together frequent revisit cycles of less than a week, and an adequate resolution for detection of 1 ha plots. Yet, in order to benefit from these advantages, it is necessary to examine the information that can be extracted... O. Beeri, S. May-tal, R. Rud, Y. Raz, R. Pelta |
11. A Hyperlocal Machine Learning Approach to Estimate NDVI from SAR Images for Agricultural FieldsThe normalized difference vegetation index (NDVI) is a key parameter in precision agriculture used globally since the 1970s. The NDVI is sensitive to the biochemical and physiological properties of the crop and is based on the Red (~650 nm) and NIR (~850 nm) spectral bands. It is used as a proxy to monitor crop growth, correlates to the crop coefficient (Kc), leaf area index (LAI), crop cover, and more. Yet, it is susceptible to clouds and other atmospheric conditions which might alter... R. Pelta, O. Beeri, T. Shilo, R. Tarshish |
12. Changes in Soil Quality when Building Ridges for Fruit PlantationMany fruit plantations are usually performed in ridges for various reasons including, escaping from a clay horizon, improving overall soil quality and drainage, among others. Normally ridges are built using the surface horizons, producing a mixture of soils layers, and therefore changing the quality of the soil at the rooting zone. We were interested in studying the changes in soil properties when building ridges in a flat alluvial soil that was planted with avocado. A detailed... H.P. Poblete, R.A. Ortega |
13. Yield Estimation for Avocado Using Systematic Sampling TechniquesAvocado is a high value crop ranking fourth among the planted fruit species in Chile with more than 32,000 ha. Yield estimation is an important challenge in avocado due to its phenology, the size of the tree, and to the large variability usually observed within the orchards. Due to the practical difficulties to sample the trees we use the following approach: 1) establish a systematic, non-aligned grid with > 20 sampling points (trees)/field, 2) previous to harvest, and once... H.P. Poblete, R.A. Ortega |
14. Analysis of the Mapping Results Using SoilOptix TM Technology in Chile After Two SeasonsSoil mapping is a key element to successfully implement Integrated Nutrient Management (INM) in high value crops. SoilOptixTM is a mapping service based on the use of gamma radiation technology that arrived in Chile in 2019. Since then, around 2000 ha have been mapped, mainly in fruit orchards and vineyards. The technology has demonstrated its value in determining the most limiting factors in new and old orchards, and the possibility of correcting them in a site-specific... R.A. Ortega, A.F. Ortega, M.C. Orellana |
15. Multi-sensor Imagery Fusion for Pixel-by-pixel Water Stress MappingEvaluating water stress in agricultural fields is fundamental in irrigation decision-making, especially mapping the in-field water stress variability as it allows real-time detection of system failures or avoiding yield loss in cases of unplanned water stress. Water stress mapping by remote sensing imagery is commonly associated with the thermal or the short-wave-infra-red (SWIR) bands. However, integration of multi-sensors imagery such as radar imagery or sensors with only visible and near-infra-red... O. Beeri, R. Pelta, Z. Sade, T. Shilo |