Open AccessArticle
A Novel Machine Learning Method for Estimating Biomass of Grass Swards Using a Photogrammetric Canopy Height Model, Images and Vegetation Indices Captured by a Drone
Agriculture 2018, 8(5), 70; https://doi.org/10.3390/agriculture8050070 -
Abstract
Silage is the main feed in milk and ruminant meat production in Northern Europe. Novel drone-based remote sensing technology could be utilized in many phases of silage production, but advanced methods of utilizing these data are still developing. Grass swards are harvested three
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Silage is the main feed in milk and ruminant meat production in Northern Europe. Novel drone-based remote sensing technology could be utilized in many phases of silage production, but advanced methods of utilizing these data are still developing. Grass swards are harvested three times in season, and fertilizer is applied similarly three times—once for each harvest when aiming at maximum yields. Timely information of the yield is thus necessary several times in a season for making decisions on harvesting time and rate of fertilizer application. Our objective was to develop and assess a novel machine learning technique for the estimation of canopy height and biomass of grass swards utilizing multispectral photogrammetric camera data. Variation in the studied crop stand was generated using six different nitrogen fertilizer levels and four harvesting dates. The sward was a timothy-meadow fescue mixture dominated by timothy. We extracted various features from the remote sensing data by combining an ultra-high resolution photogrammetric canopy height model (CHM) with a pixel size of 1.0 cm and red, green, blue (RGB) and near-infrared range intensity values and different vegetation indices (VI) extracted from orthophoto mosaics. We compared the performance of multiple linear regression (MLR) and a Random Forest estimator (RF) with different combinations of the CHM, RGB and VI features. The best estimation results with both methods were obtained by combining CHM and VI features and all three feature classes (CHM, RGB and VI features). Both estimators provided equally accurate results. The Pearson correlation coefficients (PCC) and Root Mean Square Errors (RMSEs) of the estimations were at best 0.98 and 0.34 t/ha (12.70%), respectively, for the dry matter yield (DMY) and 0.98 and 1.22 t/ha (11.05%), respectively, for the fresh yield (FY) estimations. Our assessment of the sensitivity of the method with respect to different development stages and different amounts of biomass showed that the use of the machine learning technique that integrated multiple features improved the results in comparison to the simple linear regressions. These results were extremely promising, showing that the proposed multispectral photogrammetric approach can provide accurate biomass estimates of grass swards, and could be developed as a low-cost tool for practical farming applications. Full article
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Open AccessFeature PaperArticle
Food Energy Availability from Agriculture at the Farm-Level in Southeastern Nigeria: Level, Composition and Determinants
Agriculture 2018, 8(5), 69; https://doi.org/10.3390/agriculture8050069 -
Abstract
Among the four pillars of ‘food security’ (i.e., ‘food availability’, ‘food accessibility’, ‘food stability’ and ‘food utilization’), ‘food availability (FA)’ underpins the core concept because at the micro-level it is strongly related to the overall availability of food, which is determined by domestic
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Among the four pillars of ‘food security’ (i.e., ‘food availability’, ‘food accessibility’, ‘food stability’ and ‘food utilization’), ‘food availability (FA)’ underpins the core concept because at the micro-level it is strongly related to the overall availability of food, which is determined by domestic food production, food imports and food aid. This paper examines the level of food energy availability (FEA) at the farm level, relationships between farm size and FEA and the determinants of FEA based on a survey of 400 households from Ebonyi and Anambra States of Southeastern Nigeria. FEA in this study refers to Partial Food Energy Availability (PFEA) because it excludes procurement of food from other sources, e.g., purchase from the market, borrow/exchange from others and/or receiving as food aid. Results show that the sample is dominated by small–scale farmers (81% of the total sample) owning land <1.00 ha. The average farm size is small (1.27 ha). Farmers grow multiple food crops. Sixty-eight percent of the farmers produced at least two food crops. Average PFEA is estimated at 4492.78 kcals/capita/day produced from one ha of land area. Approximately 30.92% of the total food produced is set aside for home consumption. Among the food crops, 40.70% of cassava output is set aside for home consumption while most of yam and rice are mainly destined for the market. Inverse farm size–PFEA relationship exists amongst the sampled farmers. The regression results reveal that subsistence pressure, profit motive and share of yam in total output significantly reduces PFEA whereas an increase in the share of cassava in total output significantly increases PFEA. A one percent increase in the share of cassava output will increase PFEA by 0.14%. A one percent increase in subsistence pressure will reduce PFEA by 0.98%. Farmers identified a lack of agricultural extension agents, farm inputs and basic infrastructures as the main constraints adversely affecting food production at the farm-level. Policy implications include investments targeted to improve cassava production and measure to reduce future family size by improved family planning to increase PFEA at the farm-level. Full article
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Open AccessFeature PaperArticle
The Genetic Variability of Floral and Agronomic Characteristics of Newly-Bred Cytoplasmic Male Sterile Rice
Agriculture 2018, 8(5), 68; https://doi.org/10.3390/agriculture8050068 -
Abstract
Male sterility enabled commercialization of heterosis in rice but low seed set remains a constraint on hybrid dissemination. We evaluated 216 F6 maintainer lines for agronomic and floral characteristics in augmented design and selected 15 maintainer lines, which were testcrossed with IR58025A.
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Male sterility enabled commercialization of heterosis in rice but low seed set remains a constraint on hybrid dissemination. We evaluated 216 F6 maintainer lines for agronomic and floral characteristics in augmented design and selected 15 maintainer lines, which were testcrossed with IR58025A. Five backcrosses were conducted to transfer cytoplasmic male sterility (CMS) to select maintainer lines. Newly-bred BC5:6 CMS lines were evaluated for outcrossing rates and agronomic characteristics. There were highly significant differences among 216 F6 maintainer lines for characteristics whose genotypic variance was higher than environmental variance. The phenotypic coefficient of variation was almost the same as the genotypic coefficient of variation, indicating that most phenotypic variation was due to genetics. There were highly significant differences among CMS lines for number of days to 50% flowering and maturity; stigma exertion; panicle exertion, length and weight; spikelet fertility; tillers per plant; plant height; grains per panicle; grain yield per plant; and 1000-grain weight, but not for pollen and panicle sterility during dry and wet seasons. Three CMS lines (CMS3, CMS12, and CMS14), exhibited high outcrossing rates (56.17%, 51.42% and 48.44%, respectively), which had a highly significant, positive correlation with stigma exertion (0.97), spikelet opening angle (0.82), and panicle exertion (0.95). Full article
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Open AccessArticle
The Effect of Supplemental Irrigation on Canopy Temperature Depression, Chlorophyll Content, and Water Use Efficiency in Three Wheat (Triticum aestivum L. and T. durum Desf.) Varieties Grown in Dry Regions of Jordan
Agriculture 2018, 8(5), 67; https://doi.org/10.3390/agriculture8050067 -
Abstract
One critical challenge facing the world is the need to satisfy the food requirements of the dramatically growing population. Drought stress is one of the main limiting factors in the wheat-producing regions; therefore, wheat yield stability is a major objective of wheat-breeding programs
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One critical challenge facing the world is the need to satisfy the food requirements of the dramatically growing population. Drought stress is one of the main limiting factors in the wheat-producing regions; therefore, wheat yield stability is a major objective of wheat-breeding programs in Jordan, which experience fluctuating climatic conditions in the context of global climate change. In the current study, a two-year field experiment was conducted for exploring the effect of four different water regimes on the yield, yield components, and stability of three wheat (Triticum aestivum L.; T. durum Desf.) Jordanian cultivars as related to Canopy Temperature Depression (CTD), and Chlorophyll Content (measured by Soil-Plant Analysis Development, SPAD). A split plot design was used in this experiment with four replicates. Water treatment was applied as the main factor: with and without supplemental irrigation; 0%, 50%, 75%, and 100% of field capacity were applied. Two durum wheat cultivars and one bread wheat cultivar were split over irrigation treatments as a sub factor. In both growing seasons, supplemental irrigation showed a significant increase in grain yield compared to the rain-fed conditions. This increase in grain yield was due to the significantly positive effect of water availability on yield components. Values of CTD, SPAD, harvest index, and water use efficiency (WUE) were increased significantly with an increase in soil moisture and highly correlated with grain yield. Ammon variety produced the highest grain yield across the four water regimes used in this study. This variety was characterized by the least thermal time to maturity and the highest values of CTD and SPAD. It was concluded that Ammon had the highest stability among the cultivars tested. Furthermore, CTD and SPAD can be used as important selection parameters in breeding programs in Jordan to assist in developing high-yielding genotypes under drought and heat stress conditions. Full article
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Open AccessArticle
Salt Tolerance of Six Switchgrass Cultivars
Agriculture 2018, 8(5), 66; https://doi.org/10.3390/agriculture8050066 -
Abstract
Panicum virgatum L. (switchgrass) cultivars (‘Alamo’, ‘Cimarron’, ‘Kanlow’, ‘NL 94C2-3’, ‘NSL 2009-1’, and ‘NSL 2009-2’) were evaluated for salt tolerance in two separate greenhouse experiments. In experiment (Expt.) 1, switchgrass seedlings were irrigated with a nutrient solution at an electrical conductivity (EC) of
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Panicum virgatum L. (switchgrass) cultivars (‘Alamo’, ‘Cimarron’, ‘Kanlow’, ‘NL 94C2-3’, ‘NSL 2009-1’, and ‘NSL 2009-2’) were evaluated for salt tolerance in two separate greenhouse experiments. In experiment (Expt.) 1, switchgrass seedlings were irrigated with a nutrient solution at an electrical conductivity (EC) of 1.2 dS·m−1 (control) or a saline solution (spiked with salts) at an EC of 5.0 dS·m−1 (EC 5) or 10.0 dS·m−1 (EC 10) for four weeks, once a week. Treatment EC 10 reduced the tiller number by 32% to 37% for all switchgrass cultivars except ‘Kanlow’. All switchgrass cultivars under EC 10 had a significant reduction of 50% to 63% in dry weight. In Expt. 2, switchgrass was seeded in substrates moistened with either a nutrient solution of EC 1.2 dS·m−1 (control) or a saline solution of EC of 5.0, 10.0, or 20.0 dS·m−1 (EC 5, EC 10, or EC 20). Treatment EC 5 did not affect the seedling emergence, regardless of cultivar. Compared to the control, EC 10 reduced the seedling emergence of switchgrass ‘Alamo’, ‘Cimarron’, and ‘NL 94C2-3’ by 44%, 33%, and 82%, respectively. All switchgrass cultivars under EC 10 had a 46% to 88% reduction in the seedling emergence index except ‘NSL 2009-2’. No switchgrass seedlings emerged under EC 20. In summary, high salinity negatively affected switchgrass seedling emergence and growth. Dendrogram and cluster of six switchgrass cultivars indicated that ‘Alamo’ was the most tolerant cultivar, while ‘NSL 2009-2’ was the least tolerant cultivar at both seedling emergence and growth stages. A growth-stage dependent response to salinity was observed for the remaining switchgrass cultivars. ‘NSL 2009-1’ and ‘NL 94C2-3’ were more tolerant to salinity than ‘Cimarron’ and ‘Kanlow’ at the seedling emergence stage; however, ‘Kanlow’ and ‘Cimarron’ were more tolerant to salinity than ‘NSL 2009-1’ and ‘NL 94C2-3’ at the seedling growth stage. Full article
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Open AccessArticle
Multi-Temporal Site-Specific Weed Control of Cirsium arvense (L.) Scop. and Rumex crispus L. in Maize and Sugar Beet Using Unmanned Aerial Vehicle Based Mapping
Agriculture 2018, 8(5), 65; https://doi.org/10.3390/agriculture8050065 -
Abstract
Sensor-based weed mapping in arable fields is a key element for site-specific herbicide management strategies. In this study, we investigated the generation of application maps based on Unmanned Aerial Vehicle imagery and present a site-specific herbicide application using those maps. Field trials for
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Sensor-based weed mapping in arable fields is a key element for site-specific herbicide management strategies. In this study, we investigated the generation of application maps based on Unmanned Aerial Vehicle imagery and present a site-specific herbicide application using those maps. Field trials for site-specific herbicide applications and multi-temporal image flights were carried out in maize (Zea mays L.) and sugar beet (Beta vulgaris L.) in southern Germany. Real-time kinematic Global Positioning System precision planting information provided the input for determining plant rows in the geocoded aerial images. Vegetation indices combined with generated plant height data were used to detect the patches containing creeping thistle (Cirsium arvense (L.) Scop.) and curled dock (Rumex crispus L.). The computed weed maps showed the presence or absence of the aforementioned weeds on the fields, clustered to 9 m × 9 m grid cells. The precision of the correct classification varied from 96% in maize to 80% in the last sugar beet treatment. The computational underestimation of manual mapped C.arvense and R.cripus patches varied from 1% to 10% respectively. Overall, the developed algorithm performed well, identifying tall perennial weeds for the computation of large-scale herbicide application maps. Full article
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Open AccessArticle
Relationship of Date Palm Tree Density to Dubas Bug Ommatissus lybicus Infestation in Omani Orchards
Agriculture 2018, 8(5), 64; https://doi.org/10.3390/agriculture8050064 -
Abstract
Date palm trees, Phoenix dactylifera, are the primary crop in Oman. Most date palm cultivation is under the traditional agricultural system. The plants are usually under dense planting, which makes them prone to pest infestation. The main pest attacking date palm crops
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Date palm trees, Phoenix dactylifera, are the primary crop in Oman. Most date palm cultivation is under the traditional agricultural system. The plants are usually under dense planting, which makes them prone to pest infestation. The main pest attacking date palm crops in Oman is the Dubas bug Ommatissus lybicus. This study integrated modern technology, remote sensing and geographic information systems to determine the number of date palm trees in traditional agriculture locations to find the relationship between date palm tree density and O. lybicus infestation. A local maxima method for tree identification was used to determine the number of date palm trees from high spatial resolution satellite imagery captured by WorldView-3 satellite. Window scale sizes of 3, 5 and 7 m were tested and the results showed that the best window size for date palm trees number detection was 7 m, with an overall estimation accuracy 88.2%. Global regression ordinary least square (OLS) and local geographic weighted regression (GWR) were used to test the relationship between infestation intensity and tree density. The GWR model showed a good positive significant relationship between infestation and tree density in the spring season with R2 = 0.59 and medium positive significant relationship in the autumn season with R2 = 0.30. In contrast, the OLS model results showed a weak positive significant relationship in the spring season with R2 = 0.02, p < 0.05 and insignificant relationship in the autumn season with R2 = 0.01, p > 0.05. The results indicated that there was a geographic effect on the infestation of O. lybicus, which had a greater impact on infestation severity, and that the impact of tree density was higher in the spring season than in autumn season. Full article
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Open AccessReview
Sustainable Intensification in Dryland Cropping Systems—Perspectives for Adaptions across the Western Siberian Grain Belt
Agriculture 2018, 8(5), 63; https://doi.org/10.3390/agriculture8050063 -
Abstract
The Western Siberian grain belt is of global significance in terms of agricultural production as well as carbon sequestration and biodiversity preservation. Regional downscaling of general circulation models predict increasing drought risks and water scarcity for this area. Additionally, significant land-use changes took
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The Western Siberian grain belt is of global significance in terms of agricultural production as well as carbon sequestration and biodiversity preservation. Regional downscaling of general circulation models predict increasing drought risks and water scarcity for this area. Additionally, significant land-use changes took place in this region after the dissolution of the USSR and collapse of the state farm system: Land-use intensity in Western Siberia (Russian Federation) continuously decreased on grassland, whilst on cropland the intensity increased through recultivation of abandoned cropland and rising fertilizer inputs since 2003. Together, these changing conditions have led to challenges for sustainable agriculture in this semi-arid environment. For sustainable land management, strategies for adapted crop production systems are needed. In agronomic field trials, the potential of enhanced water use efficiency as contribution to a resilient agricultural system under changing climate conditions was evaluated and related to the common practice and regional research. In participatory on-farm trials, higher average soil water content (+40%) in the top soil layer led to higher grain yield (+0.4 t ha−1) and protein yield (+0.05 t ha−1) under no-till compared to the common practice of conventional tillage. Despite this, regional research still promotes bare fallowing with beneficial effects only in the first harvest after fallow, whereas the potential of no-till was visible each year, even under above-average wet and cool growing conditions. In this case study from the Western Siberian grain belt, we depict a possible pathway to make cereal production in Western Siberia more sustainable. However, the approach of applied sustainable intensification by promoting no-till is related to the negative concomitant effect of increased herbicide applications. Due to the strict rejection of GMOs in Russian agriculture by the federal government, this is a great opportunity to maintain a large, pristine area of over 17 million km2 with a lower risk of glyphosate-dependent cropping systems. Full article
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Open AccessFeature PaperArticle
Exploring the Relationships between Greenhouse Gas Emissions, Yields, and Soil Properties in Cropping Systems
Agriculture 2018, 8(5), 62; https://doi.org/10.3390/agriculture8050062 -
Abstract
Relationships between greenhouse gas emissions, yields, and soil properties are not well known. Utilizing two datasets from long-term cropping systems in Illinois, USA, our we aim to address these knowledge gaps. The objective of this study was to explore the relationships between the
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Relationships between greenhouse gas emissions, yields, and soil properties are not well known. Utilizing two datasets from long-term cropping systems in Illinois, USA, our we aim to address these knowledge gaps. The objective of this study was to explore the relationships between the physical and chemical properties and greenhouse gas (GHG) emissions of soil, and cash crop yields over a four-year time-period and following 15 years of treatment implementation in Illinois, USA. The experimental layout was a split-plot arrangement involving rotation and tillage treatments in a randomized complete block design with four replications. The studied crop rotations were continuous corn [Zea mays L.] (CCC), corn-soybean [Glycine max (L.) Merr.] (CS), continuous soybean (SSS), and corn-soybean-wheat [Triticum aestivum L.] (CSW), with each phase being present for every year. The tillage options were chisel tillage (T) and no-tillage (NT). We used an array of multivariate approaches to analyze both of our datasets that included 31 soil properties, GHG emissions (N2O, CO2, and CH4) and cash crop yields. The results from our analyses indicate that N2O emissions are associated with a low soil pH, an increased Al concentration, the presence of soil nitrate throughout the growing season, an increase in plant available water (PAW) and an increased soil C concentration. Likewise, soil CO2 respiration was correlated with low pH, elevated Al concentrations, low Ca, increased PAW, higher levels of microbial biomass carbon (MBC), and lower water aggregate stability (WAS). Emissions of CH4 were associated with increased levels of MBC. Lastly, the yield index (YdI) was correlated with lower levels of soil Ca and available P and lower values of WAS. The association between high YdI and lower WAS can be attributed to tillage, as tillage lowers WAS, but increases yields in highly productive cropping systems in the Midwest. Full article
Open AccessArticle
Effect of Simulated Tillage in Combination with Post-Shattering Temperature Conditions on Senna obtusifolia and Xanthium strumarium Seed Survival, Seedling Emergence and Seedbank Potential
Agriculture 2018, 8(4), 61; https://doi.org/10.3390/agriculture8040061 -
Abstract
Two of the most troublesome weeds in soybean, cotton, and corn in cropping systems of mid-south United States (US) are Senna obtusifolia and Xanthium strumarium. Understanding their population dynamics, particularly weed seedling emergence patterns, is important for the timely implementation and the
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Two of the most troublesome weeds in soybean, cotton, and corn in cropping systems of mid-south United States (US) are Senna obtusifolia and Xanthium strumarium. Understanding their population dynamics, particularly weed seedling emergence patterns, is important for the timely implementation and the success of weed management strategies. Identifying the sources of variation of emergence patterns could greatly improve our ability to predict emergence timing. A three-years field study was conducted to determine the effect of environmental conditions on S. obtusifolia and X. strumarium seedling emergence and seedbank potential. The experiment was conducted with two seed sources; X. strumarium burs and S. obtusifolia seeds from a single maternal plant source, and X. strumarium burs and S. obtusifolia seeds from multiple maternal plant sources, both being exposed either to 5 cm burial depth (buried) or left on the soil surface (soil surface) in the fallow or planted in spring after their storage under chilled (chill) or room temperature (no chill) conditions. X. strumarium and S. obtusifolia seedling emergence was lower from burs and seeds that were planted in the soil in September as compared with the chill and/or no chill seeds/burs stored for six months. X. strumarium seedling emergence was reduced from 37 to 1% when burs were left on the soil surface when compared to buried burs. S. obtusifolia seedling emergence was reduced from 47 to 13% when seeds were left on the soil surface as compared to buried. At the end of the experimental period, the soil seedbank of X. strumarium had been significantly depleted, whereas the remaining seeds of S. obtusifolia were viable. Full article
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Open AccessArticle
Modelling Soil Water Content in a Tomato Field: Proximal Gamma Ray Spectroscopy and Soil–Crop System Models
Agriculture 2018, 8(4), 60; https://doi.org/10.3390/agriculture8040060 -
Abstract
Proximal soil sensors are taking hold in the understanding of soil hydrogeological processes involved in precision agriculture. In this context, permanently installed gamma ray spectroscopy stations represent one of the best space–time trade off methods at field scale. This study proved the feasibility
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Proximal soil sensors are taking hold in the understanding of soil hydrogeological processes involved in precision agriculture. In this context, permanently installed gamma ray spectroscopy stations represent one of the best space–time trade off methods at field scale. This study proved the feasibility and reliability of soil water content monitoring through a seven-month continuous acquisition of terrestrial gamma radiation in a tomato test field. By employing a 1 L sodium iodide detector placed at a height of 2.25 m, we investigated the gamma signal coming from an area having a ~25 m radius and from a depth of approximately 30 cm. Experimental values, inferred after a calibration measurement and corrected for the presence of biomass, were corroborated with gravimetric data acquired under different soil moisture conditions, giving an average absolute discrepancy of about 2%. A quantitative comparison was carried out with data simulated by AquaCrop, CRITeRIA, and IRRINET soil–crop system models. The different goodness of fit obtained in bare soil condition and during the vegetated period highlighted that CRITeRIA showed the best agreement with the experimental data over the entire data-taking period while, in presence of the tomato crop, IRRINET provided the best results. Full article
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Open AccessArticle
Characterisation of Castor (Ricinus communis L.) Seed Quality Using Fourier Transform Near-Infrared Spectroscopy in Combination with Multivariate Data Analysis
Agriculture 2018, 8(4), 59; https://doi.org/10.3390/agriculture8040059 -
Abstract
The potential of single-seed near-infrared (NIR) spectroscopy was investigated to characterise castor seeds based on their seed viability and seed oil content. Distinct differences between viable and non-viable seeds were observed in the principal component analysis (PCA) analysis. Furthermore, the PCA compared heavy
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The potential of single-seed near-infrared (NIR) spectroscopy was investigated to characterise castor seeds based on their seed viability and seed oil content. Distinct differences between viable and non-viable seeds were observed in the principal component analysis (PCA) analysis. Furthermore, the PCA compared heavy and medium seeds with light seeds, which were comparable to the clusters of viable and non-viable seeds, respectively. Prediction accuracies of 98.7% and 99.6% were obtained with the partial least squares discriminant analysis (PLS-DA) model with a classification error rate of 0.8% and 1.1% for the training set and test set, respectively. The NIR spectral regions having chemical information from the oil in castor seeds were found to be vital for determination of seed viability. Full article
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Open AccessArticle
Bringing the Consumer Back in—The Motives, Perceptions, and Values behind Consumers and Rural Tourists’ Decision to Buy Local and Localized Artisan Food—A Swedish Example
Agriculture 2018, 8(4), 58; https://doi.org/10.3390/agriculture8040058 -
Abstract
This article highlights the motivational factors behind consumers’ and tourists’ decisions to buy local artisan cheese in Jämtland (Sweden). Empirically, the case itself diverts from the typical Franco-Mediterranean case in which both the actions of producers and consumers are embedded in historical, long-term
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This article highlights the motivational factors behind consumers’ and tourists’ decisions to buy local artisan cheese in Jämtland (Sweden). Empirically, the case itself diverts from the typical Franco-Mediterranean case in which both the actions of producers and consumers are embedded in historical, long-term culinary traditions and territorial features, nor is it the typical farmers’ market or another market-driven direct produce system. The main purpose is to shed light on the motivational factors behind the purchasing decision of consumers and tourists by studying the attributes that consumers embody in the products. The article is based on two consumer surveys/short interviews, the first conducted in June 2012 and the second in February 2017. The results were tested against/related to the wider local food discussion conceptualized through four types of attributes. Namely, intrinsic and extrinsic attributes; post-modernity and environmental attributes; geographical and territorial attributes; and local and rural development attributes. The results in this article clearly show that consumers value a combination of different attributes from both market-driven direct produce systems and close typicity systems. Therefore, the construction of proximity from the point of view of the consumer can be derived from a complex set of attributes and motivational factors not normally highlighted in the localized food discussion. Full article
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Open AccessReview
An Overview of the Post-Harvest Grain Storage Practices of Smallholder Farmers in Developing Countries
Agriculture 2018, 8(4), 57; https://doi.org/10.3390/agriculture8040057 -
Abstract
Grain storage loss is a major contributor to post-harvest losses and is one of the main causes of food insecurity for smallholder farmers in developing countries. Thus, the objective of this review is to assess the conventional and emerging grain storage practices for
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Grain storage loss is a major contributor to post-harvest losses and is one of the main causes of food insecurity for smallholder farmers in developing countries. Thus, the objective of this review is to assess the conventional and emerging grain storage practices for smallholder farmers in developing countries and highlight their most promising features and drawbacks. Smallholder farmers in developing countries use conventional grain storage structures and handling systems such as woven bags or cribs to store grain. However, they are ineffective against mold and insects already present in the grain before storage. Different chemicals are also mixed with grain to improve grain storability. Hermetic storage systems are effective alternatives for grain storage as they have minimal storage losses without using any chemicals. However, hermetic bags are prone to damage and hermetic metal silos are cost-prohibitive to most smallholder farmers in developing countries. Thus, an ideal grain storage system for smallholder farmers should be hermetically sealable, mechanically durable, and cost-effective compared to the conventional storage options. Such a storage system will help reduce grain storage losses, maintain grain quality and contribute to reducing food insecurity for smallholder farmers in developing countries. Full article
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Open AccessArticle
Importance of Agronomic Practice on the Control of Wheat Leaf Diseases
Agriculture 2018, 8(4), 56; https://doi.org/10.3390/agriculture8040056 -
Abstract
Soil tillage and crop rotation are considered important tools in wheat leaf disease control; however, the results of investigations are inconsistent. The aim of the present study was to determine the effect of the soil tillage system and cropping sequence on the development
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Soil tillage and crop rotation are considered important tools in wheat leaf disease control; however, the results of investigations are inconsistent. The aim of the present study was to determine the effect of the soil tillage system and cropping sequence on the development of winter wheat leaf diseases in 2012–2017. The disease development was assessed in a two-factor experiment: (a) soil tillage system; and (b) crop rotation. Foliar fungicides were used uniformly in all variants. The results showed that tan spot (caused by Pyrenophora tritici-repentis) dominated in 2012, 2013, and 2016, but the level of Septoria tritici blotch (Zymoseptoria tritici) was essentially lower and exceeded the severity of tan spot only in 2015. The agronomic practice used significantly influenced only the development of tan spot. Reduced soil tillage and continuous wheat sowing substantially increased tan spot severity, especially when both practices were used simultaneously. Short crop rotation (only wheat and oilseed rape) provided sufficient control of tan spot in ploughed fields, whereas in non-ploughed fields, the level of this disease did not decrease. The results could be explained by differences in the pathogens’ life cycle: P. tritici-repentis ascospores in wheat debris is the main source of infection; in contrast, Z. tritici spreads by conidia from living plants. Full article
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Open AccessFeature PaperReview
Crop Systems, Quality and Protection of Diplotaxis tenuifolia
Agriculture 2018, 8(4), 55; https://doi.org/10.3390/agriculture8040055 -
Abstract
Perennial wall-rocket (Diplotaxis tenuifolia (L.) D.C.) is a herbaceous plant belonging to the Brassicaceae with a cosmopolitan distribution. Traditionally harvested as a spontaneous herb, today it is a crop species of increasing importance after the diffusion of the ready-to-use salads in the
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Perennial wall-rocket (Diplotaxis tenuifolia (L.) D.C.) is a herbaceous plant belonging to the Brassicaceae with a cosmopolitan distribution. Traditionally harvested as a spontaneous herb, today it is a crop species of increasing importance after the diffusion of the ready-to-use salads in the vegetable retail markets. Besides relevance as a food crop, its consumption is prompted by consideration in the traditional medicine of several peoples in the native areas of the Mediterranean and western Asia based on recognized health beneficial effects. In fact, the leaves have notable nutritional properties related to their contents of glucosinolates and some antioxidant compounds, such as vitamin C and flavonoids, which entitle their dietary inclusion for the prevention of cancer and cardiovascular diseases. This paper provides an overview on aspects concerning the biology, crop management, nutritional properties, industrial processing and uses of perennial wall-rocket. Full article
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Open AccessArticle
Adjustment of Weed Hoeing to Narrowly Spaced Cereals
Agriculture 2018, 8(4), 54; https://doi.org/10.3390/agriculture8040054 -
Abstract
Weed hoeing can be successfully performed in wide row crops, such as sugar beet, maize, soybean and wide spaced cereals. However, little experience is available for hoeing in narrow cereal row spaces below 200 mm. Yet, mechanical weed control can pose an alternative
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Weed hoeing can be successfully performed in wide row crops, such as sugar beet, maize, soybean and wide spaced cereals. However, little experience is available for hoeing in narrow cereal row spaces below 200 mm. Yet, mechanical weed control can pose an alternative to herbicide applications by reducing the herbicide resistant populations present in the field. In this experiment, it was investigated whether hoeing is feasible in cereals with 150 and 125 mm row spacings. The trial was set up at two locations (Ihinger Hof and Kleinhohenheim) in southwest Germany. Three different conventional hoeing sweeps, a goosefoot sweep, a no-till sweep and a down-cut side knife were adjusted to the small row widths, and hoeing was performed once with a tractor and a standard hoeing frame which was guided by a second human operator. The average grain yield, crop and weed biomass, and weed control efficacy of each treatment were recorded. The goosefoot and no-till sweep were tested at driving speeds of 4 and 6 km·h−1. The down-cut side knife was applied at 4 km·h−1. The results indicate that hoeing caused no yield decrease in comparison to a conventional herbicide application or manual weeding. The highest yield with a mechanical treatment was recorded for the no-till sweeps at both trial locations. Hoeing was performed successfully in narrowly spaced cereals of 150 and 125 mm, and the weed control efficacy of the mechanical treatments ranged from 50.9% at Kleinhohenheim to 89.1% at Ihinger Hof. Future experiments are going to focus on more distinct driving speeds ranging from 2 to 10 km·h−1 and performing more than one pass with the hoe. Additionally, combining the mechanical weeding tools with a camera-steered hoeing frame could increase accuracy, allow for higher working speeds and substitute the second human operator guiding the hoe. Full article
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Open AccessArticle
Assessing the Economic Impacts of Pesticide Regulations
Agriculture 2018, 8(4), 53; https://doi.org/10.3390/agriculture8040053 -
Abstract
Economic impacts of pesticide regulations are assessed using five alternative methodologies. The regulations include crop supply-enhancing eradication programs and crop supply-decreasing pesticide bans. Alternative assessment methodologies differ regarding assumptions about market price and crop acreage adjustments. Results show that market and producer adjustments
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Economic impacts of pesticide regulations are assessed using five alternative methodologies. The regulations include crop supply-enhancing eradication programs and crop supply-decreasing pesticide bans. Alternative assessment methodologies differ regarding assumptions about market price and crop acreage adjustments. Results show that market and producer adjustments substantially impact conclusions about winners and losers from regulations, and estimated welfare effects can differ widely between the different methodologies. For small technological changes such as the hypothetical pendimethalin regulation, farm budgeting and sector modeling yield similar estimates. For more severe technological changes—like the boll weevil eradication program—simple budgeting approaches lead to a substantial bias. Full article
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Open AccessArticle
Translocation of Endosulfan from Soil to Ginseng (Panax ginseng C. A. Meyer)
Agriculture 2018, 8(4), 52; https://doi.org/10.3390/agriculture8040052 -
Abstract
This study was conducted to examine the translocation of highly residual agrochemical in soil, the endosulfan (total), to ginseng (Panax ginseng C. A. Meyer). The soil with the level of the amount of 5.0 mg kg−1 of endosulfan (total) was prepared
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This study was conducted to examine the translocation of highly residual agrochemical in soil, the endosulfan (total), to ginseng (Panax ginseng C. A. Meyer). The soil with the level of the amount of 5.0 mg kg−1 of endosulfan (total) was prepared in a Wagner pot into which the seedling of ginseng was transplanted and then the specimens of ginseng (root, leaf, and stem) were collected quarterly and analyzed through GC-MS. The level of residual of endosulfan (total) in the soil has decreased from 4.28 mg kg−1 (April 2013) to 1.94 mg kg−1 (December 2014) while the level in the specimens of leaf and stem of ginseng respectively sampled according to its growth phase in June and September from 2013 and 2014 showed an increase from 0.56 mg kg−1 (June 2013) to 2.46 mg kg−1 (September 2013) and decrease from 0.29 mg kg−1 (June 2014) to 0.18 mg kg−1 (September 2014). For the case of the root of ginseng, the level of the amount of 10.77 mg kg−1 of endosulfan (total) was detected in June 2013 and then, the level has decreased to the level of 4.88 mg kg−1 in December 2014. The translocation of residual endosulfan (total) in soil to ginseng with time was identified. The amount of residuals of α-endosulfan and β-endosulfan was also decreased with time however, the ratio of endosulfan-sulfate, the main metabolite, was gradually increasing. The retention of metabolite (endosulfan-sulfate) in soil identified thereby thus suggests the potential of its translocation to plants in the case of the soils containing the residual of endosulfan (total). Full article
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Open AccessReview
22 Years of Governance Structures and Performance: What Has Been Achieved in Agrifood Chains and Beyond? A Review
Agriculture 2018, 8(4), 51; https://doi.org/10.3390/agriculture8040051 -
Abstract
Although the existing literature has shown that the choice of governance structure plays a key role in inter-organizational performance, the nature of construct measurability still remains equivocal. The diversity of terminologies used means that the full potential of most studies may be lost
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Although the existing literature has shown that the choice of governance structure plays a key role in inter-organizational performance, the nature of construct measurability still remains equivocal. The diversity of terminologies used means that the full potential of most studies may be lost in the confusion of indistinctive and misapplied terms. To better understand the relationship between governance structures and performance, a descriptive systematic review was conducted on the extant literature; essentially, to provide a comprehensive point of reference for researchers interested in this research area and to identify future research gaps. A simple analytical framework—Search, Appraisal, and Synthesis—was used to extract data. A total of 110 peer-reviewed journal articles were identified and analyzed. The results indicated that different governance structures are positively related to performance except for the spot market. The findings provide strong evidence that under certain circumstances, the contractual governance structure is negatively related to performance. Whereas in other circumstances, there is a positive interaction. Furthermore, the results revealed that numerous proxy indicators have been used to measure governance structures and performance. Overall, this study provides new insights on the relationship between governance structures and performance in the agrifood sector and beyond. The contribution of the study, implications, and suggestions for future research outlook are discussed in relation to governance structures and performance. Full article
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