Next Issue
Previous Issue

Table of Contents

Agronomy, Volume 8, Issue 2 (February 2018)

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Cover Story (view full-size image) Analyses of climate change impacts consistently show that cereal yields may decrease by as much as [...] Read more.
View options order results:
result details:
Displaying articles 1-16
Export citation of selected articles as:
Open AccessArticle Protein, Calcium, Zinc, and Iron Contents of Finger Millet Grain Response to Varietal Differences and Phosphorus Application in Kenya
Received: 24 July 2017 / Revised: 8 November 2017 / Accepted: 22 November 2017 / Published: 24 February 2018
PDF Full-text (1169 KB) | HTML Full-text | XML Full-text
Abstract
This study was carried out to investigate the influence of phosphorus fertilizers on the concentrations of nutrients, particularly calcium, protein, zinc, and iron in finger millet grains grown in different agro-ecologies in Kenya. The on-station experiments were carried out at Kiboko (Eastern Kenya),
[...] Read more.
This study was carried out to investigate the influence of phosphorus fertilizers on the concentrations of nutrients, particularly calcium, protein, zinc, and iron in finger millet grains grown in different agro-ecologies in Kenya. The on-station experiments were carried out at Kiboko (Eastern Kenya), Kakamega, and Alupe (Western Kenya) in 2015 during the short and long rainy seasons. The trials were laid out in a randomized complete block design (RCBD) in a 4 × 3 factorial arrangement with three replicates. The treatments comprised of four levels of phosphorus (0, 12.5, 25.0 and 37.5 kg ha−1 P2O5) and three finger millet varieties (U-15, P-224 and a local variety). Application of phosphorus significantly (p ≤ 0.05) increased the protein content of finger millet grain in varieties in all the three sites. Variety U-15 had the highest protein content (11.0%) at 25 kg ha−1 P2O5 with the control (zero P) on variety P-224 eliciting the lowest (4.4%) at Kiboko. At Kakamega, the 25 kg ha−1 P2O5 treatment with U-15 variety had the highest protein content (15.3%) while the same variety at 12.5 kg ha−1 P2O5 rate elicited the highest protein content (15.0%) at Alupe. Phosphorus application significantly enhanced the nutritional quality of finger millet grains specifically protein, calcium, iron, and zinc. Variety P-224 had the highest calcium content in all sites and highest iron content at Kakamega while the local varieties had the highest zinc content in all sites. The varieties responded differently to each quality component but generally, based on the protein content, the 25 kg ha−1 P2O5 is recommended. Full article
Figures

Figure 1

Open AccessArticle A Tool for the Evaluation of Irrigation Water Quality in the Arid and Semi-Arid Regions
Received: 19 December 2017 / Revised: 30 January 2018 / Accepted: 19 February 2018 / Published: 22 February 2018
PDF Full-text (237 KB) | HTML Full-text | XML Full-text
Abstract
In the Mediterranean arid and semi-arid regions, large amounts of low quality waters could be used for crop irrigation, but the adoption of articulated classifications with too rigid quality limits can often reduce the recoverable quantities of water and make the monitoring of
[...] Read more.
In the Mediterranean arid and semi-arid regions, large amounts of low quality waters could be used for crop irrigation, but the adoption of articulated classifications with too rigid quality limits can often reduce the recoverable quantities of water and make the monitoring of water quality too much expensive. Therefore, an evaluation of irrigation water quality based on only a few crucial parameters, which consider the crop species to be irrigated and the type of irrigation system and management adopted, can be an easy and flexible method for maximizing the reuse of wastewater and low-quality water for agricultural purposes. In this view, an irrigation water quality tool (IWQT) was developed to support farmers of arid and semi-arid regions on evaluating the use of low quality water for crop irrigation. The most significant and cheapest parameters of irrigation water quality were identified and clustered in three quality classes according to their effects on crop yield and soil fertility (agronomic quality indicators), human health (hygiene and health quality indicators), and irrigation systems (management quality indicators). According to IWQT parameters, a tool reporting a series of recommendations, including water treatment types, was implemented to guide farmers on the use of low quality irrigation water. Full article
Open AccessArticle Effect of Digestate and Biochar Amendments on Photosynthesis Rate, Growth Parameters, Water Use Efficiency and Yield of Chinese Melon (Cucumis melo L.) under Saline Irrigation
Received: 2 December 2017 / Revised: 30 January 2018 / Accepted: 13 February 2018 / Published: 20 February 2018
Cited by 1 | PDF Full-text (1747 KB) | HTML Full-text | XML Full-text
Abstract
Despite the recent interest in biochar and digestate as soil amendments for improving soil quality and increasing crop production, there is inadequate knowledge of the effect of the combination of biochar and digestate, particularly under saline irrigation conditions. A pot experiment with Chinese
[...] Read more.
Despite the recent interest in biochar and digestate as soil amendments for improving soil quality and increasing crop production, there is inadequate knowledge of the effect of the combination of biochar and digestate, particularly under saline irrigation conditions. A pot experiment with Chinese melon was conducted in a greenhouse, biochar (5%) and digestate (500 mL/pot) were used with and without the recommended mineral NPK (Nitrogen, Phosphorus and Potassium) fertilizer dose (120-150-150 Kg ha−1). The plants were irrigated with tap water (SL0) and 2 dS/m (SL1) NaCl solution. The growth, photosynthesis rate, water use efficiency (WUE) and yield of Chinese melon were affected positively when biochar was combined with digestate amendment, particularly under saline irrigation water with and without mineral NPK fertilizer. The maximum yield under normal water was obtained by digestate (SL0: 218.87 t ha−1) and biochar amendment combined with digestate (SL1: 118.8 t ha−1) under saline water. The maximum WUE values were noticed with the biochar and digestate combination under all water treatments (SL0: 32.2 t ha−1 mm−1 and SL1: 19.6 t ha−1 mm−1). It was concluded that digestate alone was more effective than the use of biochar, particularly with normal water. The combination of biochar with digestate had a significant effect on the Chinese melon growth, photosynthesis rate, water use efficiency and yield under saline irrigation, and it can be used as an alternative fertilizer for mineral NPK fertilizer. Full article
Figures

Figure 1

Open AccessArticle Dynamic Carbohydrate Supply and Demand Model of Vegetative Growth: Response to Temperature, Light, Carbon Dioxide, and Day Length
Received: 29 November 2017 / Revised: 31 January 2018 / Accepted: 13 February 2018 / Published: 16 February 2018
PDF Full-text (2095 KB) | HTML Full-text | XML Full-text
Abstract
Predicting the growth response of seedlings from the environmental responses of photosynthesis and metabolism may be improved by considering the dynamics of non-structural carbohydrate (NSC) over a diurnal cycle. Attenuation of growth metabolism when NSC content is low could explain why some NSC
[...] Read more.
Predicting the growth response of seedlings from the environmental responses of photosynthesis and metabolism may be improved by considering the dynamics of non-structural carbohydrate (NSC) over a diurnal cycle. Attenuation of growth metabolism when NSC content is low could explain why some NSC is conserved through the night. A dynamic model, incorporating diurnal variation in NSC, is developed to simulate growth of seedlings hour-by-hour. I compare predictions of this model to published growth and NSC data for seedlings that varied according to temperature, light, day length, or CO2. Prolonged-darkness experiments show a temperature dependent upper limit on the respiration capacity. Respiration is attenuated as NSC is depleted. Furthermore, when NSC is high at dawn, inhibition of photosynthesis could attenuate the accumulation of NSC under low temperature, high light, or high CO2. These concepts are used to simulate plant metabolism and growth rates and diurnal variation of NSC in tomato seedlings under two light levels and various temperatures. Comparison of other results using the same model parameters show the dynamic model could predict results for starch and starch-less plants, and when growth was affected by CO2 enrichment and day length. Full article
(This article belongs to the Special Issue Photosynthetic Carbon Metabolism to Enhance Crop Productivity)
Figures

Figure 1

Open AccessReview The ALMT Gene Family Performs Multiple Functions in Plants
Received: 5 January 2018 / Revised: 4 February 2018 / Accepted: 5 February 2018 / Published: 14 February 2018
Cited by 1 | PDF Full-text (2900 KB) | HTML Full-text | XML Full-text
Abstract
The aluminium activated malate transporter (ALMT) gene family is named after the first member of the family identified in wheat (Triticum aestivum L.). The product of this gene controls resistance to aluminium (Al) toxicity. ALMT genes encode transmembrane proteins that
[...] Read more.
The aluminium activated malate transporter (ALMT) gene family is named after the first member of the family identified in wheat (Triticum aestivum L.). The product of this gene controls resistance to aluminium (Al) toxicity. ALMT genes encode transmembrane proteins that function as anion channels and perform multiple functions involving the transport of organic anions (e.g., carboxylates) and inorganic anions in cells. They share a PF11744 domain and are classified in the Fusaric acid resistance protein-like superfamily, CL0307. The proteins typically have five to seven transmembrane regions in the N-terminal half and a long hydrophillic C-terminal tail but predictions of secondary structure vary. Although widely spread in plants, relatively little information is available on the roles performed by other members of this family. In this review, we summarized functions of ALMT gene families, including Al resistance, stomatal function, mineral nutrition, microbe interactions, fruit acidity, light response and seed development. Full article
Figures

Figure 1

Open AccessReview Cropping Systems and Climate Change in Humid Subtropical Environments
Received: 15 December 2017 / Revised: 7 February 2018 / Accepted: 10 February 2018 / Published: 14 February 2018
PDF Full-text (2484 KB) | HTML Full-text | XML Full-text
Abstract
In the future, climate change will challenge food security by threatening crop production. Humid subtropical regions play an important role in global food security, with crop rotations often including wheat (winter crop) and soybean and maize (summer crops). Over the last 30 years,
[...] Read more.
In the future, climate change will challenge food security by threatening crop production. Humid subtropical regions play an important role in global food security, with crop rotations often including wheat (winter crop) and soybean and maize (summer crops). Over the last 30 years, the humid subtropics in the Northern Hemisphere have experienced a stronger warming trend than in the Southern Hemisphere, and the trend is projected to continue throughout the mid- and end of century. Past rainfall trends range, from increases up to 4% per decade in Southeast China to −3% decadal decline in East Australia; a similar trend is projected in the future. Climate change impact studies suggest that by the middle and end of the century, wheat yields may not change, or they will increase up to 17%. Soybean yields will increase between 3% and 41%, while maize yields will increase by 30% or decline by −40%. These wide-ranging climate change impacts are partly due to the region-specific projections, but also due to different global climate models, climate change scenarios, single-model uncertainties, and cropping system assumptions, making it difficult to make conclusions from these impact studies and develop adaptation strategies. Additionally, most of the crop models used in these studies do not include major common stresses in this environment, such as heat, frost, excess water, pests, and diseases. Standard protocols and impact assessments across the humid subtropical regions are needed to understand climate change impacts and prepare for adaptation strategies. Full article
(This article belongs to the Special Issue Adapting Crop Productivity to Climate Change)
Figures

Figure 1

Open AccessArticle Quantifying Variability in Maize Yield Response to Nutrient Applications in the Northern Nigerian Savanna
Received: 23 December 2017 / Revised: 7 February 2018 / Accepted: 8 February 2018 / Published: 10 February 2018
PDF Full-text (3231 KB) | HTML Full-text | XML Full-text
Abstract
Diagnostic on-farm nutrient omission trials were conducted over two cropping seasons (2015 and 2016) to assess soil nutrients related constraints to maize yield in the northern Nigerian savanna agro-ecological zone and to quantify their variability. Two sets of trials were conducted side by
[...] Read more.
Diagnostic on-farm nutrient omission trials were conducted over two cropping seasons (2015 and 2016) to assess soil nutrients related constraints to maize yield in the northern Nigerian savanna agro-ecological zone and to quantify their variability. Two sets of trials were conducted side by side, one with an open pollinated maize variety (OPV) and the other one with a hybrid maize variety and each set had six equal treatments laid out in 198 farmers’ fields. The treatments comprised (i) a control, (ii) a PK (‘−N,’ without N), (iii) an NK (‘−P,’ without P), (iv) an NP (‘−K,’ without K), (v) an NPK and (vi) an NPK + S + Ca + Mg + Zn + B (‘+SMM,’ NPK plus secondary macro- and micro-nutrients). Moderate to a large variability in most soil characteristics was observed in the studied fields. Consequently, cluster analysis revealed three distinct yield-nutrient response classes common for the two types of maize varieties. These define classes were fields that have (i) no-response to any nutrient, (ii) a large response to N and P and (iii) a large response to N alone. Although overall yield performance of OPV and hybrid varieties was similar, a distinct fourth class was identified for the hybrid variety, (iv) fields with a large response to N and secondary macro- and micro-nutrients. The results indicate that the large variability in soil nutrients related constraints need to be accounted for to optimize maize yield in the northern Nigerian savanna. The development of field- and area-specific fertilizer recommendations is highly needed, using simple decision support tools that consider variable soil fertility conditions and yield responses as obtained from this study. Full article
Figures

Figure 1

Open AccessReview Molecular Markers Improve Breeding Efficiency in Apomictic Poa Pratensis L.
Received: 6 December 2017 / Revised: 25 January 2018 / Accepted: 5 February 2018 / Published: 10 February 2018
PDF Full-text (826 KB) | HTML Full-text | XML Full-text
Abstract
Kentucky bluegrass (Poa pratensis L.) is a highly adapted and important turfgrass species in cool-season climates. It has high and variable polyploidy, small and metacentric chromosomes, and a facultative apomictic breeding system. As a result of the polyploidy and apomixis, identifying hybrids
[...] Read more.
Kentucky bluegrass (Poa pratensis L.) is a highly adapted and important turfgrass species in cool-season climates. It has high and variable polyploidy, small and metacentric chromosomes, and a facultative apomictic breeding system. As a result of the polyploidy and apomixis, identifying hybrids for Mendelian selection, identifying fixed apomictic progeny of desirable hybridizations for cultivar development, or differentiating among cultivars with subtle phenotypic differences is challenging without the assistance of molecular markers. Herein, we show data and review previous research showing the uses and limitations of using molecular markers for hybrid detection, apomixis assessment, and cultivar discrimination. In order to differentiate among different apomictic offtypes, both molecular markers and flow cytometry are necessary. For assessing similarity among progeny of hybridizations, as well as discriminating among cultivars, sets of markers are necessary and cryptic molecular variation must be considered. High throughput genotyping platforms are critical for increased genotyping efficiency. Full article
(This article belongs to the Special Issue Turfgrass Biology, Genetics, and Breeding)
Figures

Figure 1

Open AccessArticle Towards Remote Estimation of Radiation Use Efficiency in Maize Using UAV-Based Low-Cost Camera Imagery
Received: 24 November 2017 / Revised: 23 January 2018 / Accepted: 30 January 2018 / Published: 6 February 2018
Cited by 1 | PDF Full-text (2009 KB) | HTML Full-text | XML Full-text
Abstract
Radiation Use Efficiency (RUE) defines the productivity with which absorbed photosynthetically active radiation (APAR) is converted to plant biomass. Readily used in crop growth models to predict dry matter accumulation, RUE is commonly determined by elaborate static sensor measurements in the field. Different
[...] Read more.
Radiation Use Efficiency (RUE) defines the productivity with which absorbed photosynthetically active radiation (APAR) is converted to plant biomass. Readily used in crop growth models to predict dry matter accumulation, RUE is commonly determined by elaborate static sensor measurements in the field. Different definitions are used, based on total absorbed PAR (RUEtotal) or PAR absorbed by the photosynthetically active leaf tissue only (RUEgreen). Previous studies have shown that the fraction of PAR absorbed (fAPAR), which supports the assessment of RUE, can be reliably estimated via remote sensing (RS), but unfortunately at spatial resolutions too coarse for experimental agriculture. UAV-based RS offers the possibility to cover plant reflectance at very high spatial and temporal resolution, possibly covering several experimental plots in little time. We investigated if (a) UAV-based low-cost camera imagery allowed estimating RUEs in different experimental plots where maize was cultivated in the growing season of 2016, (b) those values were different from the ones previously reported in literature and (c) there was a difference between RUEtotal and RUEgreen. We determined fractional cover and canopy reflectance based on the RS imagery. Our study found that RUEtotal ranges between 4.05 and 4.59, and RUEgreen between 4.11 and 4.65. These values are higher than those published in other research articles, but not outside the range of plausibility. The difference between RUEtotal and RUEgreen was minimal, possibly due to prolonged canopy greenness induced by the stay-green trait of the cultivar grown. The procedure presented here makes time-consuming APAR measurements for determining RUE especially in large experiments superfluous. Full article
Figures

Figure 1

Open AccessTechnical Note Autonomous Mower vs. Rotary Mower: Effects on Turf Quality and Weed Control in Tall Fescue Lawn
Received: 19 December 2017 / Revised: 22 January 2018 / Accepted: 3 February 2018 / Published: 6 February 2018
PDF Full-text (238 KB) | HTML Full-text | XML Full-text
Abstract
Autonomous mowers are battery-powered machines designed for lawn mowing that require very low human labour. Autonomous mowers can increase turf quality and reduce local noise and pollution compared with gasoline-powered rotary mowers. However, very little is known about the effects of autonomous mowing
[...] Read more.
Autonomous mowers are battery-powered machines designed for lawn mowing that require very low human labour. Autonomous mowers can increase turf quality and reduce local noise and pollution compared with gasoline-powered rotary mowers. However, very little is known about the effects of autonomous mowing on encroaching weeds. The aim of this research was to compare the effects of an autonomous mower and an ordinary gasoline-powered mower on weed development in an artificially infested tall fescue (Festuca arundinacea Schreb.) turf with different nitrogen (N) rates. A three-way factor experimental design with three replications was adopted. Factor A consisted of three N rates (0, 75, and 150 kg ha−1), factor B consisted of two mowing systems (autonomous mower vs. walk-behind gasoline rotary mower equipped for mulching), and factor C which consisted of four different transplanted weed species: (a) Bellis perennis L., (b) Trifolium repens L.; (c) Trifolium subterraneum L.; and (d) Lotus corniculatus L. Of these, B. perennis is a rosette-type plant, while the other three species are creeping-type plants. The interaction between mowing system and transplanted weed species showed that the four transplanted weed species were larger when mowed by the autonomous mower than by the rotary mower. The autonomous mower yielded larger weeds probably because the constant mowing height caused the creeping weed species to grow sideways, since the turfgrass offered no competition for light. N fertilization increased turf quality and mowing quality, and also reduced spontaneous weed infestation. Autonomous mowing increased turf quality, mowing quality, but also the percentage of spontaneous weed cover. Full article
(This article belongs to the Special Issue Turfgrass Biology, Genetics, and Breeding)
Open AccessReview Effects of Climate Change on Grassland Biodiversity and Productivity: The Need for a Diversity of Models
Received: 14 December 2017 / Revised: 29 January 2018 / Accepted: 31 January 2018 / Published: 2 February 2018
Cited by 1 | PDF Full-text (262 KB) | HTML Full-text | XML Full-text
Abstract
There is increasing evidence that the impact of climate change on the productivity of grasslands will at least partly depend on their biodiversity. A high level of biodiversity may confer stability to grassland ecosystems against environmental change, but there are also direct effects
[...] Read more.
There is increasing evidence that the impact of climate change on the productivity of grasslands will at least partly depend on their biodiversity. A high level of biodiversity may confer stability to grassland ecosystems against environmental change, but there are also direct effects of biodiversity on the quantity and quality of grassland productivity. To explain the manifold interactions, and to predict future climatic responses, models may be used. However, models designed for studying the interaction between biodiversity and productivity tend to be structurally different from models for studying the effects of climatic impacts. Here we review the literature on the impacts of climate change on biodiversity and productivity of grasslands. We first discuss the availability of data for model development. Then we analyse strengths and weaknesses of three types of model: ecological, process-based and integrated. We discuss the merits of this model diversity and the scope for merging different model types. Full article
(This article belongs to the Special Issue Climate Change in Agriculture: Impacts and Adaptations)
Open AccessArticle Cultivar Variety and Added Potassium Influence the Nutraceutical and Antioxidant Content in Hydroponically Grown Basil (Ocimum basilicum L.)
Received: 31 December 2017 / Revised: 22 January 2018 / Accepted: 24 January 2018 / Published: 30 January 2018
Cited by 1 | PDF Full-text (1631 KB) | HTML Full-text | XML Full-text
Abstract
The potential impact of increased levels of potassium (K+) in hydroponic solution on the production of bioactive compounds, which provide added value to products, is relevant for local economy and human health. This research pursues assessing different levels of K+
[...] Read more.
The potential impact of increased levels of potassium (K+) in hydroponic solution on the production of bioactive compounds, which provide added value to products, is relevant for local economy and human health. This research pursues assessing different levels of K+ on the nutrition of basil, an important aromatic crop in the arid region of La Laguna, northern México, where water scarcity demands the conversion from open-field agriculture to hydroponics. A randomized complete block design with a factorial arrangement (3 × 4) was used to determine the content of nutraceutical components, including polyphenolic compounds, flavonoids, anthocyanins, vitamin C, chlorophylls, and the antioxidant capacity of three varieties of hydroponic basil, with four doses of K+ in the nutrient solution, 7, 9, 11 and 13 mmol L−1. The analysis of variance showed significant differences (p ≤ 0.001) in most of the response variables, caused by the genotype and doses of K+. The antioxidant capacity of assessed cultivars was improved when doses of K+ were increased in the nutrient solution. Furthermore, the antioxidant capacity was positively correlated to the content of flavonoids (r = 0.621), anthocyanins (r = 0.655) and total phenolic compounds (r = 0.549). In conclusion, the nutraceutical content was increased in basil when controlling K+ in the nutrient solution. Full article
Figures

Graphical abstract

Open AccessArticle Grassland Establishment of Dwarf Napiergrass (Pennisetum purpureum Schumach) by Planting of Cuttings in the Winter Season
Received: 10 November 2017 / Revised: 20 January 2018 / Accepted: 24 January 2018 / Published: 28 January 2018
PDF Full-text (978 KB) | HTML Full-text | XML Full-text
Abstract
We investigated a new method for the establishment of dwarf Napiergrass by covering stem cuttings with soil in the winter season analogously to summer establishment in sugarcane. Three experiments were conducted, including measuring the labor involved in plant establishment, and an extension study
[...] Read more.
We investigated a new method for the establishment of dwarf Napiergrass by covering stem cuttings with soil in the winter season analogously to summer establishment in sugarcane. Three experiments were conducted, including measuring the labor involved in plant establishment, and an extension study was applied to livestock producers’ fields in two locations. Using this technique, we obtained an emerged plant density of over two plants/m2. Moreover, this proved a simple and labor-saving method compared with manual or mechanical transplanting. Sowing of Italian ryegrass at the same time as covering cuttings of dwarf Napiergrass with soil could control spring weed growth without disturbing the emergence of dwarf Napiergrass, suggesting the feasibility of a double-cropping forage production system in the region. Full article
Figures

Figure 1

Open AccessFeature PaperArticle Utilizing Process-Based Modeling to Assess the Impact of Climate Change on Crop Yields and Adaptation Options in the Niger River Basin, West Africa
Received: 21 December 2017 / Revised: 19 January 2018 / Accepted: 23 January 2018 / Published: 27 January 2018
PDF Full-text (7521 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Climate change is estimated to substantially reduce crop yields in Sub-Saharan West Africa by 2050. Yet, a limited number of studies also suggest that several adaptation measures may mitigate the effects of climate change induced yield loss. In this paper, we used AquaCrop,
[...] Read more.
Climate change is estimated to substantially reduce crop yields in Sub-Saharan West Africa by 2050. Yet, a limited number of studies also suggest that several adaptation measures may mitigate the effects of climate change induced yield loss. In this paper, we used AquaCrop, a process-based model developed by the FAO (The Food and Agriculture Organization, Rome, Italy), to quantify the risk of climate change on several key cereal crops in the Niger Basin. The crops analyzed include maize, millet, and sorghum under rain fed cultivation systems in various agro-ecological zones within the Niger Basin. We also investigated several adaptation strategies, including changes in the sowing dates, soil nutrient status, and cultivar. Future climate change is estimated using nine ensemble bias-corrected climate model projection results under RCP4.5 and RCP8.5 (RCP—Representative Concentration Pathway) emissions scenario at mid future time period, 2021/25–2050. The results show that on average, temperature had a larger effect on crop yields so that the increase in precipitation could still be a net loss of crop yield. Our simulated results showed that climate change effects on maize and sorghum yield would be mostly positive (2% to 6% increase) in the Southern Guinea savanna zone while at the Northern Guinea savanna zone it is mostly negative (2% to 20% decrease). The results show that at the Sahelian zone the projected changes in temperature and precipitation have little to no impact on millet yield for the future time period, 2021/25–2050. In all agro-ecological zones, increasing soil fertility from poor fertility to moderate, near optimal and optimal level significantly reversed the negative yield change respectively by over 20%, 70% and 180% for moderate fertility, near optimal fertility, and optimal fertility. Thus, management or adaptation factors, such as soil fertility, had a much larger effect on crop yield than the climatic change factors. These results provide actionable guidance on effective climate change adaptation strategies for rain fed agriculture in the region. Full article
(This article belongs to the Special Issue Climate Change in Agriculture: Impacts and Adaptations)
Figures

Figure 1

Open AccessArticle On-Farm Demonstrations with a Set of Good Agricultural Practices (GAPs) Proved Cost-Effective in Reducing Pre-Harvest Aflatoxin Contamination in Groundnut
Received: 13 November 2017 / Revised: 22 December 2017 / Accepted: 10 January 2018 / Published: 24 January 2018
PDF Full-text (646 KB) | HTML Full-text | XML Full-text
Abstract
Aflatoxin contamination in groundnut is an important qualitative issue posing a threat to food safety. In our present study, we have demonstrated the efficacy of certain good agricultural practices (GAPs) in groundnut, such as farmyard manure (5 t/ha), gypsum (500 kg/ha), a protective
[...] Read more.
Aflatoxin contamination in groundnut is an important qualitative issue posing a threat to food safety. In our present study, we have demonstrated the efficacy of certain good agricultural practices (GAPs) in groundnut, such as farmyard manure (5 t/ha), gypsum (500 kg/ha), a protective irrigation at 90 days after sowing (DAS), drying of pods on tarpaulins after harvest in farmers’ fields. During 2013–2015, 89 on-farm demonstrations were conducted advocating GAPs, and compared with farmers’ practices (FP) plots. Farmers’ awareness of GAPs, and knowledge on important aspects of groundnut cultivation, were also assessed during our experimentation in the selected villages under study. Pre-harvest kernel infection by Aspergillus flavus, aflatoxin contamination, and pod yields were compared in GAPs plots, vis-à-vis FP plots. The cost of cultivation in both the plots was calculated and compared, based on farmer’s opinion surveys. Results indicate kernel infections and aflatoxins were significantly lower, with 13–58% and 62–94% reduction, respectively, in GAPs plots over FP. Further, a net gain of around $23 per acre was realized through adoption of GAPs by farmers besides quality improvement of groundnuts. Based on our results, it can be concluded that on-farm demonstrations were the best educative tool to convince the farmers about the cost-effectiveness, and adoptability of aflatoxin management technologies. Full article
Figures

Figure 1

Open AccessArticle Diversity of Maize Kernels from a Breeding Program for Protein Quality III: Ionome Profiling
Received: 27 November 2017 / Revised: 8 January 2018 / Accepted: 15 January 2018 / Published: 23 January 2018
PDF Full-text (4437 KB) | HTML Full-text | XML Full-text
Abstract
Densities of single and multiple macro- and micronutrients were estimated in the mature kernels of 1348 accessions in 13 maize genotypes. The germplasm belonged to stiff stalk (SS) and non-stiff stalk (NS) heterotic groups (HGs) with one (S1) to four (S4) years of
[...] Read more.
Densities of single and multiple macro- and micronutrients were estimated in the mature kernels of 1348 accessions in 13 maize genotypes. The germplasm belonged to stiff stalk (SS) and non-stiff stalk (NS) heterotic groups (HGs) with one (S1) to four (S4) years of inbreeding (IB), or open pollination (OP), and with opaque or translucent endosperm (OE and TE, respectively). Indices were calculated for macronutrients (M-Index), micronutrients (m-Index) and an index based on Fe and Zn densities (FeZn-Index). The objectives were to (1) build predictive models and quantify multivariate relationships between single and multiple nutrients with physical and biochemical constituents of the maize kernel; (2) quantify the effects of IB stages and endosperm textures, in relation to carbon and nitrogen allocation, on nutrients and their indices; and (3) develop and test the utility of hierarchical multi-way classification of nutrients with kernel color space coordinates. Differences among genotypes and among IB stages accounted for the largest amount of variation in most nutrients and in all indices, while genotypic response to IB within HGs explained 52.4, 55.9, and 76.0% of variation in the M-Index, m-Index, and FeZn-Index, respectively. Differences in C and N allocation among HGs explained more variation in all indices than respective differences in allocation among endosperm (E) textures, while variation decreased with sequential inbreeding compared to OP germplasm. Specific color space coordinates indicated either large macronutrient densities and M-Index, or large micronutrient densities, m-Index, and FeZn-Index. These results demonstrated the importance of genotypes and the C:N ratio in nutrient allocation, as well as bivariate and multiple interrelationships. Full article
Figures

Figure 1

Back to Top