Hasil untuk "Agriculture (General)"

Zhongsheng Zhang, Zhongsheng Zhang, Zhongsheng Zhang et al.

Light strongly influences the carbon (C) metabolism of seaweed through both algal carbon content and organic carbon release, thereby driving the carbon cycling of coastal oceans. However, the response of seaweed organic carbon release to varying light intensities remains an underexplored area of research. This study aimed to fill this gap by analyzing the effects of four different light intensities (5, 50, 200, and 500 μmol m–2 s–1) on the growth, carbon content, and organic carbon release of two strains (W28–42 and WO15-4) of Pyropia haitanensis. The results showed that as light intensity increased, both strains experienced an initial rise in growth rate followed by a decline, with the highest growth observed at 200 μmol m–2 s–1. Simultaneously, tissue C content increased with light intensity, whereas the nitrogen (N) and phosphorus (P) contents exhibited decreasing trends. This led to increases in the C:N and C:P ratios, indicating that high light intensity may enhance C fixation and suppress the absorption of N and P. Of particular interest was the difference in organic carbon release between the two strains. The W28–42 strain’s rate of dissolved organic carbon (DOC) release increased significantly with light intensity, whereas the WO15–4 strain’s DOC release rate remained unaffected by variations in light intensity. The particulate organic carbon (POC) release rates of both strains increased under higher light intensity, with the W28–42 strain showing a more substantial increase than the WO15–4 strain. This study demonstrates that the release of DOC by P. haitanensis exhibits distinct strain-specific responses to variations in light intensity, a result that may be attributed to differences in photosynthetic physiology and genetic makeup. These insights provide a foundation for enhancing the efficiency of fishery carbon sinks through the manipulation of light intensity.

Grishin Igor, Selivanov Victor, Rudenko Marina et al.

It is generally accepted that UAVs - unmanned aerial vehicles, otherwise known as drones, are used only for military purposes. This is a misconception: since the 60s of the last century, Russian and American specialists have been building unmanned UAVs not only for the armies of their countries, but also for peaceful purposes. The purpose of the article is to study the possibilities and progress in the development of drones for civil and needs. In preparing and writing the article, such research methods as general scientific methods of historical and logical, abstract and concrete, analysis and synthesis, comparisons and analogies were used. The main result of the study is the conclusion that unmanned aerial vehicles can be successfully used for civilian purposes, and not just for military purposes. Drones are now actively used for agricultural and environmental purposes. They are called “eco-drones”. They are no different from ordinary ones; the prefix is designed to emphasize their purely peaceful, scientific purpose.

K. Fue, W. Porter, E. Barnes et al.

In this review, we examine opportunities and challenges for 21st-century robotic agricultural cotton harvesting research and commercial development. The paper reviews opportunities present in the agricultural robotics industry, and a detailed analysis is conducted for the cotton harvesting robot industry. The review is divided into four sections: (1) general agricultural robotic operations, where we check the current robotic technologies in agriculture; (2) opportunities and advances in related robotic harvesting fields, which is focused on investigating robotic harvesting technologies; (3) status and progress in cotton harvesting robot research, which concentrates on the current research and technology development in cotton harvesting robots; and (4) challenges in commercial deployment of agricultural robots, where challenges to commercializing and using these robots are reviewed. Conclusions are drawn about cotton harvesting robot research and the potential of multipurpose robotic operations in general. The development of multipurpose robots that can do multiple operations on different crops to increase the value of the robots is discussed. In each of the sections except the conclusion, the analysis is divided into four robotic system categories; mobility and steering, sensing and localization, path planning, and robotic manipulation.

Solomon Olum, X. Gellynck, J. Juvinal et al.

Unlike most studies that focused on specific innovations, this study systematically analyzed farmers’ adoption of agricultural innovations in general. It reports willingness to pay (WTP; willingness to accept (WTA)) as a proxy for adoption, its determinants, applied methods, and statistical models. After searching and screening, 80 studies qualified for review. Majority (n = 30) of studies focused on farmers’ WTP for innovations in agricultural water provision or environmental and crop protection (n = 35), while the remaining studies handled crop or animal improvement innovations. Most studies were performed in developing countries, using stated preference methods for economic valuation, with 55% of the studies (n = 44) applying contingent valuation compared to 39% taking choice modeling approach. While farmers are generally willing to pay premium for improvement in agriculture technologies, WTP (WTA) depends on the innovation (system). For example, premiums ranged from about 0.125 to 2 USD/m3 of water depending on water supply (e.g. ground vs. surface water). Furthermore, the determinants of farmers’ WTP can be grouped into sociodemographic, biophysical, technological, institutional, and behavioral factors. As illustrated by relatively high WTP, the review demonstrates that farmers embrace most innovations, regardless of the context and methods applied.

M. Michels, V. Bonke, O. Musshoff

Flavio B. P. Malavazi, R. Guyonneau, Jean-Baptiste Fasquel et al.

The purpose of the work presented in this paper is to develop a general and robust approach for autonomous robot navigation inside a crop using LiDAR (Light Detection And Ranging) data. To be as robust as possible, the robot navigation must not need any prior information about the crop (such as the size and width of the rows). The developed approach is based on line extractions from 2D point clouds using a PEARL based method. In this paper, additional filters and refinements of the PEARL algorithm are presented in the context of crop detection. A penalization of outliers, a model elimination step, a new model search and a geometric constraint are proposed to improve the crop detection. The approach has been tested over a simulator and compared with classical PEARL and RANSAC based approaches. It appears that adding those modification improved the crop detection and thus the robot navigation. Those results are presented and discussed in this paper. It can be noticed that even if this paper presents simulated results (to ease the comparison with other algorithms), the approach also has been successfully tested using an actual Oz weeding robot, developed by the French company Naio Technologies.

Katia Pinello, Irina Amorim, Isabel Pires et al.

Analysis of canine and feline tumor malignancy data can help clinicians identify high-risk patients and make more accurate decisions. Based on a sample of 16,272 cancer records, including 3266 cats and 13,006 dogs, collected from January 2019 to December 2021 in the Vet-OncoNet Network database, this study aimed to compare the tumor malignancy profile between cats and dogs, considering animal-related factors (sex, age, and breed), topography, and geographic location using a mixed-effects logistic regression model. Cats had a higher proportion of malignant tumors (78.7%) than dogs (46.2%), and the malignancy profile was very different regarding tumors’ topographies. The mean age of malignant tumors occurred eight months later than benign ones (9.1, SD = 3.4; 9.8, SD = 3.2), in general. Species (OR = 3.96, 95%CI 3.57: 4.39) and topography (MOR = 4.10) were the two most important determinants of malignancy risk. Female dogs had a higher risk than male dogs (OR = 1.19, 95%CI 1.08: 1.31), which does not appear to be the case in cats (OR = 0.98, 95%CI 0.77: 1.23). Breed contributed significantly to differences in malignancy risk in dogs (MOR = 1.56), particularly in pit bulls and boxers. District of residence was not so relevant in predicting malignancy risk (MOR = 1.14). In both species, the risk of malignancy increased by approximately 20% every three years. It could be hypothesized that species differences in genetic structure may contribute to tumor malignancy.

Oswaldo Guzmán López, María del Carmen Nuñez-Camargo, Alejandro Salinas-Castro

Background. Cultivation of forage grasses is an important component in the dual-purpose cattle production system; however, insect pests can decrease fresh material yields. Objective. To taxonomically identify the causal agent that damages the cultivars Panicum maximum (Jacq.) cv. Mombasa and Panicum maximum cv. Zuri. Methodology. In two locations in the central region of Veracruz, specimens of an insect in the larval and pupal stages were collected using the quadrant method in an area of 50 ha. Subsequently, in the laboratory, larvae were boiled for two minutes and preserved in 70% alcohol. Meanwhile, pupae were placed in a brood chamber with foliage to obtain adults and to extract their genitalia, which represents the most important morphological structure for the identification of a species. Results. The total number of collected larvae was 650, and 65 pupae, all reaching the adult stage. Based on the taxonomic morphology, the species Mocis latipes or striped grassworm was determined. Damage was estimated at approximately 40% per hectare. Implications. Correct identification of the pest insect allows the implementation of a strategy for proper management. Conclusion. The species M. latipes was identified in forage grasses P. maximum cv. Mombasa and P. maximum cv. Zuri in Veracruz.

C. Ashley, S. Maxwell

K. Fuglie

Abstract Declining rates of growth in crop yields, slowing investment in agricultural research, and rising commodity prices has raised concerns of a general slowdown in global agricultural productivity. However, there is no evidence of a general slowdown in the rate of growth in agricultural output. Thus, for productivity to slow, input use in agriculture would have to be expanding at an accelerated rate. Available data suggest that growth rates in agricultural land, labor and inputs in total have been steadily slowing over time, leading to accelerated growth rates in their average productivities. Increased cropping intensity has compensated for declining growth in average yield per harvest to keep land productivity growth from falling. Most of the acceleration in world agricultural productivity growth has taken place in developing countries; for industrialized countries, long-term trends show gradually declining agricultural productivity growth.

D. Pimentel, A. Marklein, Megan A. Toth et al.

Mariane Peripolli, Sylvio H. B. Dornelles, Sidinei J. Lopes et al.

ABSTRACT The objective of this study was to evaluate the effect of the application of the biostimulants Seed+ and Crop+ on physiological and production variables and on the activity of antioxidant enzymes (superoxide dismutase - SOD and guaiacol peroxidase - POD) in tomato plants subjected to two soil water conditions. The experiment was carried out in a greenhouse, in a 2 x 2 x 6 factorial scheme, with two times of application of the biostimulants (flowering and fruiting), two soil water conditions (50 and 100% of soil water holding capacity) and six biostimulants (control treatment; Seed+; Seed+ + Crop+ 1x; Seed+ + Crop+ 2x; Crop+ 1x; + Crop+ 2x). The exprimental design was completely randomized, with four repetitions. The biostimulants Seed+ and Crop+ increased the quantum yield of photosystem II (Fv/Fm), regardless of the time of application and water condition of the soil. The biostimulants Seed+ + Crop+ 2x and Crop+ 2x stood out in the pre-morning period, with an average Fv/Fm of 0.813, under the conditions tested. The highest SOD activity (372.12 U mg-1 of protein) was obtained with Crop+ 2x biostimulant in fruiting and under water deficit. For POD, when under water deficit, the best results were obtained with the biostimulants Seed+ + Crop+ 2x, Crop+ 1x and Crop+ 2x in flowering (810.94; 691.19 and 921.59 U mg-1 protein) and in fruiting (703.60; 800.00 and 972.62 U mg-1 protein). Thus, the use of Seed+ and Crop+ biostimulants can be an alternative to help mitigate the damage caused by water deficit in tomato crop.

Ajar Nath Yadav

Plant-microbes interaction is a key for plant growth, development and soil health. An understanding of plant microbiome and their beneficial attributes could have multiple benefits towards sustainable agriculture. Recently, a great emphasis is given on decoding of microbial diversity associated with plants from diverse habitats. Microbial diversity is considered important for maintaining for the sustainability of agriculture production systems. In the 90s, the interaction of microbes with plants was simply thought of as being an effect, but today it is recognized as a process with a high level of complexity in which at least different type of microbes share information without sharing the same spaces from a cellular perspective. In general, there are three kinds of plant-microbes interactions are considered i.e. epiphytic, endophytic and rhizospheric.

Agriculture Editorial Office

The editorial team greatly appreciates the reviewers who have dedicated their considerable time and expertise to the journal’s rigorous editorial process over the past 12 months, regardless of whether the papers are finally published or not [...]

H. Selod, K. Deininger, Rabah Arezki

This paper studies the determinants of foreign land acquisition for large-scale agriculture. To do so, gravity models are estimated using data on bilateral investment relationships, together with newly constructed indicators of agro-ecological suitability in areas with low population density as well as land rights security. Results confirm the central role of agro-ecological potential as a pull factor. In contrast to the literature on foreign investment in general, the quality of the business climate is insignificant whereas weak land governance and tenure security for current users make countries more attractive for investors. Implications for policy are discussed.

Chien Thang Doan, Thi Ngoc Tran, Van Bon Nguyen et al.

Chitosanase has attracted great attention due to its potential applications in medicine, agriculture, and nutraceuticals. In this study, <i>P. mucilaginosus</i> TKU032, a bacterial strain isolated from Taiwanese soil, exhibited the highest chitosanase activity (0.53 U/mL) on medium containing shrimp heads as the sole carbon and nitrogen (C/N) source. Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, a chitosanase isolated from <i>P. mucilaginosus</i> TKU032 cultured on shrimp head medium was determined at approximately 59 kDa. The characterized chitosanase showed interesting properties with optimal temperature and thermal stability up to 70 &#176;C. Three chitosan oligosaccharide (COS) fractions were isolated from hydrolyzed colloidal chitosan that was catalyzed by TKU032 chitosanase. Of these, fraction I showed the highest &#945;-glucosidase inhibitor (aGI) activity (65.86% at 20 mg/mL); its inhibitory mechanism followed the mixed noncompetitive inhibition model. Fractions II and III exhibited strong 2,2-diphenyl1-picrylhydrazyl (DPPH) radical scavenging activity (79.00% at 12 mg/mL and 73.29% at 16 mg/mL, respectively). In summary, the COS fractions obtained by hydrolyzing colloidal chitosan with TKU032 chitosanase may have potential use in medical or nutraceutical fields due to their aGI and antioxidant activities.

Eldo Yoel Flores del Castillo, Gladys Julia Álvarez Paz

En la estación de investigaciones de granos Sur del Jíbaro, en la provincia Sancti Spíritus, durante la campaña húmeda 2016-2017, se evaluaron dos poblaciones de arroz para determinar la variabilidad genética en base a sus caracteres morfo-agronómicos. PIACuba-4 y PIACuba-5 son poblaciones portadoras del gen de androesterilidad, obtenidas por mejora poblacional a través de la selección recurrente. Fueron sembradas en parcelas mediante la tecnología de trasplante, en un área de 700 m2. Para evaluar las plantas de forma individual se adoptó un marco de siembra de 0.30 x 0.25 metros, los caracteres evaluados fueron: longitud del tallo, rendimiento por planta, cantidad de granos por panícula, longitud de las panículas, número de hijos por planta, longitud de los granos y peso de mil granos. Los datos se procesaron mediante una estadística descriptiva para datos agrupados por distribución de frecuencias; en ambas poblaciones se observó variabilidad genética y esta varió en dependencia de la población y el carácter evaluado. Se logró determinar la variabilidad genética de las poblaciones PIACuba-4 y PIACuba-5, los caracteres que mostraron mayor coefi ciente de variación fueron la longitud del tallo, el rendimiento por planta, el número de granos por panícula y el número de hijos por planta. Otros caracteres como la longitud de la panícula, longitud de los granos y peso de 1 000 granos mostraron coefi cientes de variación moderados. A partir de la evaluación morfo-agronómica de las poblaciones, se seleccionaron plantas promisorias con características apropiadas para la cosecha mecanizada y se colectaron semillas de 120 líneas seleccionadas, 66 originadas de la población PIACuba-4 y 54 derivadas de PIACuba-5.

Frank A. Chapman, Richard D. Miles

Color in fish is mostly genetically determined, but they are unable to produce red, orange, yellow, green, and some blue colors themselves. They get these colors from their food. Fish raised in aquariums or recirculating water systems without pigment supplementation in their diet will fade and lose their vibrant hues. Even in ponds, dietary pigment supplementation can make fishes brighter and more variably colored, just like their wild counterparts. This 6-page fact sheet written by F. A. Chapman and R. D. Miles and published by the UF/IFAS School of Forest Resources and Conservation, Program in Fisheries and Aquatic Sciences, addresses how ornamental fish get their colors and provides a list of ingredient sources for diets that can be used to enhance and intensify fish colors. http://edis.ifas.ufl.edu/fa192 Accessibility Summary: In accordance with Title II regulations this content meets all points of exemption as Archived web content and/or Preexisting conventional electronic documents.

M. Eichhorn, P. Paris, F. Herzog et al.

Rodrigo Ferreira da Silva, Marcia Matsuoka, Gilvan Moisés Bertollo et al.

The inclusion of winter cover crops and fertilization with nitrogen to the soil can have an effect on their biological and microbiological attributes. The aim of this study was to evaluate biological and microbiological attributes in soil under different winter cover crops and nitrogen doses. The experiment was conducted at the Frederico Westphalen-RS campus of the Federal University of Santa Maria (UFSM) in a Rhodic Hapludox soil. The experimental design was a randomized block in factorial arrangement (2 x 10): 10 winter cover crops systems (Fallow [control], black oats, white oats, ryegrass, forage turnip, vetch, white lupine; black oat + forage turnip; black oat + vetch and black oat + vetch + fodder turnip), and two nitrogen rates in the form of urea applied in successive crops of beans common and maize, with four replications. We assessed the biological attributes (Margalef’s richness, Simpson’s dominance, Shannon’s diversity and abundance of organisms) and microbiological (carbon and nitrogen microbial biomass, basal respiration, metabolic quotient and microbial quotient of the soil). The fallow with wild species and white lupine showed greater Simpson’s dominance and abundance of organisms due to the increase in the number of individuals of the order Collembola. Vetch improved the biological attributes of the soil with increase in Collembola abundance and diversity of organisms of soil fauna. The application of nitrogen favored the microbial biomass carbon and reduced the metabolic quotient.