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Recovery of eggplant field waste as a source of phytochemicals
No full textThe influence of ripening stage was evaluated on fruit characteristics of three widely cultivated eggplant cultivars (Birgah, Black Bell and Black Moon), with the aim to characterize their fruit residual waste for phytochemicals extraction. At overripening stage, eggplant fruits showed the highest average weight, dry matter content and weight incidence of the pulp. Total anthocyanins concentration of the peel (mainly represented by nasunin) was higher at commercial ripening, whereas total polyphenols (most of all 5-O-caffeoylquinic acid) and steroidal glycoalkaloids (α-solasonine and α-solamargine) peaked at the overripening stage. Because of these modifications, every ton of fresh fruit gave up to 59 g of total anthocyanins, 1054 g CAE of total polyphenols and 252 g of total glycoalkaloids, depending on cultivar and fruit ripening stage. This study highlighted the possibility to manage the choice of cultivar and harvest time in the view of valorise this raw material for phytochemical extraction.</p
A model-based exploration of farm-household livelihood and nutrition indicators to guide nutrition-sensitive agriculture interventions
No full textAssessing progress towards healthier people, farms and landscapes through nutrition-sensitive agriculture (NSA) requires transdisciplinary methods with robust models and metrics. Farm-household models could facilitate disentangling the complex agriculture-nutrition nexus, by jointly assessing performance indicators on different farm system components such as farm productivity, farm environmental performance, household nutrition, and livelihoods. We, therefore, applied a farm-household model, FarmDESIGN, expanded to more comprehensively capture household nutrition and production diversity, diet diversity, and nutrient adequacy metrics. We estimated the potential contribution of an NSA intervention targeting the diversification of home gardens, aimed at reducing nutritional gaps and improving livelihoods in rural Vietnam. We addressed three central questions: (1) Do ‘Selected Crops’ (i.e. crops identified in a participatory process) in the intervention contribute to satisfying household dietary requirements?; (2) Does the adoption of Selected Crops contribute to improving household livelihoods (i.e. does it increase leisure time for non-earning activities as well as the dispensable budget)?; and (3) Do the proposed nutrition-related metrics estimate the contribution of home-garden diversification towards satisfying household dietary requirements? Results indicate trade-offs between nutrition and dispensable budget, with limited farm-household configurations leading to jointly improved nutrition and livelihoods. FarmDESIGN facilitated testing the robustness and limitations of commonly used metrics to monitor progress towards NSA. Results indicate that most of the production diversity metrics performed poorly at predicting desirable nutritional outcomes in this modelling study. This study demonstrates that farm-household models can facilitate anticipating the effect (positive or negative) of agricultural interventions on nutrition and the environment, identifying complementary interventions for significant and positive results and helping to foresee the trade-offs that farm-households could face. Furthermore, FarmDESIGN could contribute to identifying agreed-upon and robust metrics for measuring nutritional outcomes at the farm-household level, to allow comparability between contexts and NSA interventions.</p
Unravelling the variability and causes of smallholder maize yield gaps in Ethiopia
No full textEthiopia has achieved the second highest maize yield in sub-Saharan Africa. Yet, farmers’ maize yields are still much lower than on-farm and on-station trial yields, and only ca. 20% of the estimated water-limited potential yield. This article provides a comprehensive national level analysis of the drivers of maize yields in Ethiopia, by decomposing yield gaps into efficiency, resource and technology components, and accounting for a broad set of detailed input and crop management choices. Stochastic frontier analysis was combined with concepts of production ecology to estimate and explain technically efficient yields, the efficiency yield gap and the resource yield gap. The technology yield gap was estimated based on water-limited potential yields from the Global Yield Gap Atlas. The relative magnitudes of the efficiency, resource and technology yield gaps differed across farming systems; they ranged from 15% (1.6 t/ha) to 21% (1.9 t/ha), 12% (1.3 t/ha) to 25% (2.3 t/ha) and 54% (4.8 t/ha) to 73% (7.8 t/ha), respectively. Factors that reduce the efficiency yield gap include: income from non-farm sources, value of productive assets, education and plot distance from home. The resource yield gap can be explained by sub-optimal input use, from a yield perspective. The technology yield gap comprised the largest share of the total yield gap, partly due to limited use of fertilizer and improved seeds. We conclude that targeted but integrated policy design and implementation is required to narrow the overall maize yield gap and improve food security.</p
Association mapping and genetic dissection of drought-induced canopy temperature differences in rice
No full textDrought-stressed plants display reduced stomatal conductance, which results in increased leaf temperature by limiting transpiration. In this study, thermal imaging was used to quantify the differences in canopy temperature under drought in a rice diversity panel consisting of 293 indica accessions. The population was grown under paddy field conditions and drought stress was imposed for 2 weeks at flowering. The canopy temperature of the accessions during stress negatively correlated with grain yield (r= –0.48) and positively with plant height (r=0.56). Temperature values were used to perform a genome-wide association (GWA) analysis using a 45K single nucleotide polynmorphism (SNP) map. A quantitative trait locus (QTL) for canopy temperature under drought was detected on chromosome 3 and fine-mapped using a high-density imputed SNP map. The candidate genes underlying the QTL point towards differences in the regulation of guard cell solute intake for stomatal opening as the possible source of temperature variation. Genetic variation for the significant markers of the QTL was present only within the tall, low-yielding landraces adapted to drought-prone environments. The absence of variation in the shorter genotypes, which showed lower leaf temperature and higher grain yield, suggests that breeding for high grain yield in rice under paddy conditions has reduced genetic variation for stomatal response under drought
Early-onset preeclampsia, plasma microRNAs, and endothelial cell function
No full textBackground: Preeclampsia is a hypertensive pregnancy disorder in which generalized systemic inflammation and maternal endothelial dysfunction are involved in the pathophysiology. MiRNAs are small noncoding RNAs responsible for post-transcriptional regulation of gene expression and involved in many physiological processes. They mainly downregulate translation of their target genes. Objective: We aimed to compare the plasma miRNA concentrations in preeclampsia, healthy pregnant women, and nonpregnant women. Furthermore, we aimed to evaluate the effect of 3 highly increased plasma miRNAs in preeclampsia on endothelial cell function in vitro. Study Design: We compared 3391 (precursor) miRNA concentrations in plasma samples from early-onset preeclamptic women, gestational age–matched healthy pregnant women, and nonpregnant women using miRNA 3.1. arrays (Affymetrix) and validated our findings by real-time quantitative polymerase chain reaction. Subsequently, endothelial cells (human umbilical vein endothelial cells) were transfected with microRNA mimics (we choose the 3 miRNAs with the greatest fold change and lowest false-discovery rate in preeclampsia vs healthy pregnancy). After transfection, functional assays were performed to evaluate whether overexpression of the microRNAs in endothelial cells affected endothelial cell function in vitro. Functional assays were the wound-healing assay (which measures cell migration and proliferation), the proliferation assay, and the tube-formation assay (which assesses formation of endothelial cell tubes during the angiogenic process). To determine whether the miRNAs are able to decrease gene expression of certain genes, RNA was isolated from transfected endothelial cells and gene expression (by measuring RNA expression) was evaluated by gene expression microarray (Genechip Human Gene 2.1 ST arrays; Life Technologies). For the microarray, we used pooled samples, but the differently expressed genes in the microarray were validated by real-time quantitative polymerase chain reaction in individual samples. Results: No significant differences (fold change 1.2 with a false-discovery rate <0.05) were found in miRNA plasma concentrations between healthy pregnant and nonpregnant women. The plasma concentrations of 26 (precursor) miRNAs were different between preeclampsia and healthy pregnancy. The 3 miRNAs that were increased with the greatest fold change and lowest false-discovery rate in preeclampsia vs healthy pregnancy were miR-574-5p, miR-1972, and miR-4793-3p. Transfection of endothelial cells with these miRNAs in showed that miR-574-5p decreased (P<.05) the wound-healing capacity (ie, decreased endothelial cell migration and/or proliferation) and tended (P<.1) to decrease proliferation, miR-1972 decreased tube formation (P<.05), and also tended (P<.1) to decrease proliferation, and miR-4793-3p tended (P<.1) to decrease both the wound-healing capacity and tube formation in vitro. Gene expression analysis of transfected endothelial cells revealed that miR-574-5p tended (P<.1) to decrease the expression of the proliferation marker MKI67. Conclusion: We conclude that in the early-onset preeclampsia group in our study different concentrations of plasma miRNAs are present as compared with healthy pregnancy. Our results suggest that miR-574-5p and miR-1972 decrease the proliferation (probably via decreasing MKI67) and/or migration as well as the tube-formation capacity of endothelial cells. Therefore, these miRNAs may be antiangiogenic factors affecting endothelial cells in preeclampsia.</p
Foliar herbivory by caterpillars and aphids differentially affects phytohormonal signalling in roots and plant defence to a root herbivore
No full textPlant-mediated interactions are an important force in insect ecology. Through such interactions, herbivores feeding on leaves can affect root feeders. However, the mechanisms regulating the effects of above-ground herbivory on below-ground herbivores are poorly understood. Here, we investigated the performance of cabbage root fly larvae (Delia radicum) on cabbage plants (Brassica oleracea) previously exposed to above ground herbivores belonging to two feeding guilds: leaf chewing diamondback moth caterpillars (Plutella xylostella) or phloem-feeding cabbage aphids (Brevicoryne brassicae). Our study focusses on root-herbivore performance and defence signalling in primary roots by quantifying phytohormones and gene expression. We show that leaf herbivory by caterpillars, but not by aphids, strongly attenuates root herbivore performance. Above-ground herbivory causes changes in primary roots in terms of gene transcripts and metabolites involved in plant defence. Feeding by below-ground herbivores strongly induces the jasmonate pathway in primary roots. Caterpillars feeding on leaves cause a slight induction of the primary root jasmonate pathway and interact with plant defence signalling in response to root herbivores. In conclusion, feeding by a leaf chewer and a phloem feeder differentially affects root-herbivore performance, root-herbivore-induced phytohormonal signalling, and secondary metabolites.</p
International comparison of pig production costs 2018 : Results of InterPIG
No full textThe cost of pig production in the Netherlands is in a medium position, compared to the Netherlands’ direct neighbours, as it is characterized by a high sow performance and feed efficiency, as well as high costs for environmental protection and animal welfare. In piglet production, the Netherlands has a rather favourable cost position. This analysis is based on the InterPIG network.In light of the current market situation, it is necessary for European producers and supply chains toprepare for a future price collapse. Since the Western European market is a front-runner in focusingon sustainability and animal welfare, EU producers should focus on long-term cooperation and supply to high-end markets
Innovative irrigation water management: a strategy to increase yield and reduce salinity hazard of small scale irrigation in Ethiopia
No full textTo address the problem of water scarcity and to achieve food self-sufficiency, huge efforts and massive irrigation developments have been made in the last twenty-five years by the Ethiopian Government. However, the performance of many small-scale irrigation (SSI) schemes is still very poor. Deficient irrigation water management is one of the major factors challenging the success and the sustainability of the SSI. Farmers are constrained by inappropriate irrigation management strategies, which result in irrigation water scarcity, yield loss and undesirable environmental impacts in most SSI. The issue of sustainability is given hardly attention. This thesis tries to assess, understand and evaluate the current irrigation water management practices in relation to crop yield and soil salinization and then come-up with simple and innovative irrigation water management strategies that can influence the farmers’ decision and enable them to cope with the problem of water scarcity and soil salinity. In Chapter 2 farmers’ irrigation water management practices, challenges, perceptions and adaptation were studied. We evaluated farmers survey data, field observations and measurements and found that the farmers’ perception of the major causes for aggravating water scarcity, crop yield decline and soil salinization were in line with field observations. The overall plot level and scheme level adaptation strategies of the farmers were not good enough. The farmers are constrained by lack of technical knowledge, weak enforcement capability of the Water Users Association (WUA) and poor irrigation infrastructures to manage the irrigation water properly at plot as well as at scheme level. The government involvement on sustainability of irrigation schemes is poor. Also, the top-down approach by local government authorities has been constraining the farmers’ adaptation strategies. The study showed that allowing beneficiaries to make their own decision resulted in innovative drought adaptation strategies. For sustainable utilization of the irrigation scheme, priority should be given to interventions focused on improvement of water efficiency at farm as well as at scheme level. In Chapter 3 we developed a simple irrigation scheduling method based on an FAO procedure (Brouwer et al., 1989), the Hargreaves ET0 equation and the opinions of local farmers and extension agents. Then, under participation and close observation of farmers the method was compared to CropWat simulated and local (Traditional) scheduling practices, using maize as indicator crop. We found that the simple irrigation schedule method resulted in higher grain yield, substantial irrigation water saving and subsequently in significant improvement of water productivity as compared to the other approaches. Farmers’ and experts’ opinions were in favour of the Practical scheduling method. The practical irrigation scheduling method is thus recommended for maize in the Gumselassa area. The presented procedure can be adopted for preparation of irrigation calendars of other crops, and in other regions. In Chapter 4 we presented a sustainable utilization of the scarce irrigation water resources using cyclic (conjunctive) irrigation strategies for the production of onion. The effects of irrigation strategies using fresh water, moderately-saline water and cyclic combinations of both waters on onion yield and soil salinization were evaluated based on two years experimental data. The study was conducted under close observation and involvement of farmers and extension agents. The results indicated that the cyclic irrigation strategies are promising options for the production of onion without undue onion yield reduction and soil salinization as compared to irrigation using fresh water. In Chapter 5 the long-term (ten years) impact of cyclic irrigation strategies on relative onion yield and soil health were evaluated. Climatic data, and data collected from the irrigation scheme and the field experiment (Chapter 4) were used to calibrate and validate the Soil-Water-Atmosphere-Plant (SWAP) model. Two scenarios, i.e. 60 mm pre-plant irrigation (PPI) for the 1st case and 70 mm PPI plus 20 percent leaching fraction (LF) for the 2nd case, were used for long-term simulations. Results of the simulation revealed that salinity build-up is critically affected by irrigation water qualities and the application frequencies and the amount of annual rainfall. Irrigating using seepage water resulted in lower onion yield and higher salt accumulation in the root-zone, for both scenarios. Considering soil salinization, results of the long-term simulation indicated that, the cyclic irrigation strategies can be used safely through increasing the PPT to 70 mm and introducing 20% LF
Dairy farming system markers: The correlation of forage and milk fatty acid profiles from organic, pasture and conventional systems in the Netherlands
No full textThe relationships between the fatty acid (FA) composition in forage and milk (F&M) from different dairy systems were investigated. Eighty milk samples and 91 forage samples were collected from 40 farms (19 organic, 11 pasture and 10 conventional) in the Netherlands, during winter and summer. The FA profiles of F&M samples were measured with gas chromatography. The results showed that the F&M of organic farms were significantly differentiated from the F&M of other farms, both in summer and winter. The differences are likely due to the different grazing strategies in summer and different forage composition in winter. The Pearson's correlation results showed the specific relationship between individual FAs in forages and related milk. A PLS-DA model was applied to classify all milks samples, resulting in 87.5% and 83.3% correct classifications of training set and validation set.</p