Agro-ecological Zones Of Malawi Research Articles

Household Food Security Status and Diet Diversity Predictors of Mother Child-Dyads from Rural Smallholders in Three Agroecological Zones of Malawi

ABSTRACT Data from mother-child dyads (n = 375) living in rural smallholder farming households in Malawi was utilized. Households with an average income of >$4.2 US dollars per member had 60% lower odds (OR: 0.40, 95%CI: 0.19–0.82) of food insecurity. Household food insecurity was a predictor of Minimum Dietary Diversity for Women (MDD-W) (OR: 0.43, 95%CI: 0.21–0.89). Children whose female caregivers met MDD-W had 37 times higher odds (OR: 37.6, 95%CI: 13.9–117) of meeting the recommended dietary diversity score. To address food and nutrition security in this population, an approach that encompasses women’s empowerment and income diversification is required.

The paradox of safe milk supply by small-scale dairy farmers in Sub-Saharan Africa: insights based on current practices in Malawi

Abstract This research paper aimed to assess milking and milk handling practices among small-scale dairy farmers and determine the presence of E. coli in raw and processed liquid milk in Malawi. A total of 113 dairy farmers were interviewed across three agroecological zones of Malawi. Eighty-seven (87) processed and raw milk samples were collected from selected food stores and dairy farms and tested for E. coli. Ninety-five percent of small-scale dairy farmers had at most 2 milking cows, with daily average milk production of less than 10 L. Sixty-nine percent cleaned milking utensils using untreated water, and the farmers had no refrigerators. Eighty-eight percent held raw milk for over 6 hours at room temperature. Escherichia coli was found to be widely distributed in raw milk (76%) and pasteurized milk (75%), averaging 5.38 ± 1.82 and 2.47 ± 1.02 log cfu/ml, respectively. In conclusion, this study demonstrates that Malawian small-scale dairy farmers employ poor milking and post-milking practices, which compromise the socioeconomic environment of small-scale dairy farmers.

Isolation Characterization and Diversity of Indigenous Pesticide Degrading Microbes from Selected Agro Ecological Zones of Malawi

Pesticide xenobiotics have a great impact on bio argumentation, bio-magnification, and environment degradation regardless of being adopted by green revolution technologies. Bioremediation is widely accepted because it’s cheap, practical at the same time environmentally friendly. Bioremediation advocates indigenous microbes use to degrade pesticides, therefore a study has been performed to show prospects of degrading microorganisms. The study isolated microbes from different agro ecological zones to assess their capacity to utilize some pesticide as sole carbon source complimented by the presence of laccase gene. Biochemical test and genetic characterization using 16S rDNA genes were used in identification. Diversified species and strains of genus Enterobacter, Klebsiella, Pseudomonas, Pantoea and Leclercia, were found to degrade cypermethrin and acetochlor but no microbe was found to degrade dimethoate. The study adds new strain of microbes involved in degradation of cypermethrin and acetochlor and also strains that that can degrade both. The study puts proposition that pest infestation in fields is a result of abundance of xenobiotic degrading microbes due to natural selection pressure not pesticide resistance of the pest.

Effect of combining organic manure and inorganic fertilisers on maize–bush bean intercropping

SummaryIn sub-Saharan Africa (SSA), farmers intercrop common beans with maize but apply inorganic or organic fertilisers targeting only maize. Effects of this practice on bush bean yield have not been fully evaluated with respect to input use and compatibility when intercropped with maize. An on-farm trial managed by smallholder community members was conducted to assess the influence of various soil fertility management options and cropping systems on the yield of two bush bean genotypes (SER45 and SER83) in two agro-ecological zones of Malawi. The farmer-managed trials were laid out in split-plot design, with the bean genotypes as main plots and a combination of the soil fertility management options (i.e., no input, manure, fertiliser and fertiliser + manure) and cropping systems (i.e., sole crop and intercrop) as subplots. The trials were affected by terminal drought and dry spells, but results show that manure and fertiliser application enhanced the resilience of the drought-tolerant bean genotypes. The genotype SER45 was responsive to manure application in the sole crop, giving a 44.4% yield increase over no-manure application. In sole cropping with fertiliser plus manure, bean yields improved by 40.1% for SER45 and 78.3% for SER83 relative to the no-input control. Although sole cropping had higher bean yields, the treatment with manure and fertiliser had a higher land equivalence ratio for intercrop of 1.54 for SER45 and 1.32 for SER83 over sole cropping. These results show that, under smallholder farmer management, the climate adaptability of bush bean genotypes could be enhanced by the combined application of organic and inorganic fertilisers in maize–bean intercrop. The combined application also enhances whole-farm productivity of the common maize–bean intercrop practice than monocrop, hence is of benefit to most low-input smallholder farmers of SSA.

Carbon sequestration and selected hydraulic characteristics under conservation agriculture and traditional tillage practices in Malawi

Conservation agriculture (CA) is increasingly promoted among smallholder farmers of sub-Saharan Africa in a quest to improve food security while sustaining the natural resource base of the agro-ecosystems where agriculture is based. The aim of this study was to investigate the effects of CA and traditional tillage on soil organic carbon (SOC) and selected hydraulic properties in two contrasting agro-ecological zones of Malawi. Six farmers hosted on-farm trials in each location, with each farmer having the following treatments: CA with continuous sole maize (CA-SM), CA with maize–legume intercrops (CA-ML), and traditional tillage with continuous sole maize (CT-SM). Soil samples were randomly collected in October 2015, from farmers’ fields located in Chipeni, Chinguluwe, Lemu, and Zidyana where CA had been implemented for 10 years (2005–2015) at six depth intervals: 0–10, 10–20, 20–40, 40–60, 60–80, and 80–100 cm. Bulk density, soil water characteristics, and pore size distribution were determined using undisturbed core samples. At all sites, CA improved total SOC, carbon stocks, and the stable fraction of particulate organic carbon. Maize–legume intercropping under CA had 35%, 33%, and 73% more total SOC than CT-SM in Chipeni, Lemu, and Zidyana respectively. In Chinguluwe and Lemu, CA-ML had 0.54 and 0.50 g kg–1 respectively more stable fraction of particulate organic carbon (POMP) than CT-SM; whereas in Chipeni, CA-SM had 0.73 g kg–1 higher POMP compared with CT-SM. CA also improved soil porosity, pore size distribution, and water retention capacity by increasing the proportion of mesopores and micropores compared with CT-SM. Thus, changing management practices from CT-SM to CA has the potential to improve the soil organic matter and soil hydraulic properties across agro-ecological zones in Malawi, which is important for sustainable agriculture. Farmers should be encouraged to minimise tillage, retain residues as mulch on the soil surface, and practice crop rotation.

Diversifying conservation agriculture and conventional tillage cropping systems to improve the wellbeing of smallholder farmers in Malawi

Food production and the wellbeing of smallholder farmers are constrained by their limited financial resources, poor market access, and inadequate institutional support in southern and eastern Africa. Conservation agriculture (CA)–minimal soil disturbance, year-round ground cover, and diverse crop rotations–is being promoted to sustainably boost crop production, increase household income, and diversify diets for better nutrition. In this study, three cropping systems–continuous no-till maize, CA rotation, and conventional tillage rotation–were established on smallholder farms in the Nkhotakota and Dowa districts, two distinct agroecological zones in Malawi. Diverse three-year crop rotations in CA and conventional tillage systems included the alternative food crops sweet potato and cassava and the grain legumes common bean, soybean, cowpea, and pigeonpea. The effects of cropping system on labor use and financial returns, which served as a rough indicator of feasibility and farmer wellbeing, were analyzed for three years from 2011 to 2014. Over the three years of the study, continuous no-till maize produced the greatest gross and net revenues, despite also having greater production costs than CA and conventional systems. Although substantially less profitable than continuous no-till maize, the diversified CA and conventional tillage rotations were profitable for smallholder farmers, partially due to lower production costs. Sensitivity analysis was used to test the robustness of each cropping system under varying labor, input, and output price scenarios. Altering farmgate prices had the greatest impact on profitability, regardless of the crop grown. The input and output prices for maize were stable over the course of the study so that continuous no-till maize was the most robust cropping system. In contrast, high input cost and output price variability for alternative crops increased risk compared to maize, which may reduce their appeal to smallholder farmers. Reducing the risk of conservation agriculture rotations could provide smallholder farmers with more diversified diets and greater ecosystem services, such as greater rainwater infiltration and storage to withstand dry spells. Based on the results of this study, policies that reduce input price variability and increase farmgate prices of alternative food crops would have the greatest impact on the adoption of diverse crop rotations in Malawi.

English

The aim of the present study was to determine the nutrient composition of Cleome gynandra L. Nutrient content determination of C. gynandra was limited in the previous studies done in Malawi. C. gynandra is a readily available vegetable used for relish and medicine. The study was done from February to March 2014. Nutrient analysis was done on C. gynandra. L. leaf samples collected from different agro-ecological zones in Malawi. Nutrient analyses included moisture, protein, crude fibre, ash, iron, calcium and zinc. All the analysis of the nutrients was done on dry weight basis. Results obtained indicated significant differences (p<0.05) in ash, iron and calcium contents ranging from 5.2 to 6.88, 22.93 mg/100 g – 44.7 and 1667.0 – 2497.5 mg/100 g, respectively. However C. gynandra from different agro ecological zones did not differ significantly (p > 0.05) in moisture content ranging from 79.28– 83.58 g/100 g, protein content ranging from 3.85– 5.80 g/100 g, crude fibre content ranging from 1.76– 2.06 g/100 g, vitamin C ranging from 214.31– 319.12 mg/100 g and zinc ranging from 2.28 – 2.9 mg/100 g. This study revealed that C. gynandra contains macro and micro nutrients which are essential for the growth and maintenance of the human body. Hence, it can be promoted for consumption to contribute some nutrients to the diet. The values generated by this study can contribute to Malawi Food Composition database. Key words: Agro ecological zone, Cleome gynandra, Malawi, nutrients.

English

Evaluation of dry matter, starch, beta-carotene content and stability of eight orange-fleshed sweet potato genotypes was conducted at Bunda College in Malawi. Genotypes LU06/0527, LU06/0252, LU06/0428, LU06/0299, LU06/0258, BV/009, Kenya and Zondeni were evaluated. The genotypes were grown in three agro-ecological zones of Malawi namely Maseya in Chikhwawa District representing low altitude areas with hot climate; Bunda in Lilongwe District representing medium altitude with warm climate and Bembeke in Dedza District representing high altitude areas with cool climate. Harvested tubers were evaluated for dry matter, starch and beta-carotene content using spectrophotometry. Analysis of variance on the main effects between genotypes and environments as well as Interaction Principle Component Analysis (IPCA) for the residual multiplication interaction between genotypes and environments for beta-carotene content in the eight genotypes were conducted. Results showed significant differences in dry matter, starch and beta-carotene content among genotypes and across sites. Zondeni produced highest dry matter (34.4%) while BV/009 was the least (26.8%). Genotype LU06/0252 produced highest beta-carotene (6793.2 μg/100 g) followed by Zondeni (5620.9 μg/100 g). Beta-carotene content increased significantly with decreasing altitude and was highest at Maseya (4258.5 μg/100 g) followed by Bunda (3556.2 μg/100 g). Stability analysis showed that Kenya (SPN/O) was the most stable genotype in beta-carotene content across the sites. Bembeke was the most stable site while Maseya recorded highest beta-carotene content but was unstable site. Key words: Orange-fleshed sweet potato, agro-ecological zones, beta-carotene content, starch content, dry matter content.

Crop production and soil water management in conservation agriculture, no-till, and conventional tillage systems in Malawi

Smallholder farming in southern and eastern Africa is constrained by low water-use efficiency, frequent dry spells, and drought. Conservation agriculture (CA), defined as minimal soil disturbance, year-round ground cover, and crop rotations, is being promoted as a way to sustainably improve water-use efficiency, reduce soil erosion, and boost crop production. In this study, three cropping systems – continuous no-till maize, CA rotation, and conventional tillage rotation – were established on smallholder farms in the Nkhotakota and Dowa districts, two distinct agroecological zones in Malawi. Three-year crop rotations of cassava, cowpea, and maize and cassava, soybean, and maize were implemented in CA and conventional tillage, respectively, in Nkhotakota. In Dowa, a 3-year rotation of sweet potato, bean, and maize was implemented in both CA and conventional tillage. Cropping systems were analyzed for their impact on infiltration, soil moisture content, sediment runoff, earthworm and termite abundance, and crop production from 2011 to 2014. In Nkhotakota, which had high potential evapotranspiration and low soil water-holding capacity, residue retention was positively correlated with infiltration and no-till and CA increased soil water content (0–60cm) compared to conventional tillage by an average of 20mm. In Dowa, which had lower potential evapotranspiration, eliminating tillage and retaining residue did not improve infiltration or soil water content. In 2013/2014, no-till and CA reduced sediment runoff by 1537kgha−1 and 1309kgha−1 in Nkhotakota and 346kgha−1 and 209kgha−1 in Dowa, respectively, compared to conventional tillage. Tillage and residue management did not have a significant impact on sweet potato, cassava, bean, soybean, or cowpea production. Crop rotations had the greatest impact on maize yields in 2013/14, with CA and conventional tillage rotations increasing maize yields compared to no-till maize by 2525kgha−1 and 2145kgha−1 in Dowa and 1364kgha−1 and 469kgha−1 in Nkhotakota, respectively. However, cumulative protein production was greater in no-till than CA and conventional tillage rotations in Dowa and greater than conventional rotations in Nkhotakota. Rotation crop productivity needs to be improved with better yielding grain legumes and other higher protein crops before widespread adoption of diverse rotations can occur on smallholder farms in eastern and southern Africa.

Fungal metabolites diversity in maize and associated human dietary exposures relate to micro-climatic patterns in Malawi

This study investigated the diversity of fungal metabolites in maize across four agro-ecological zones of Malawi. A total of 90 maize samples (for human consumption), collected from farmsteads, were analysed for 235 fungal metabolites using liquid chromatography-tandem mass spectrometry. A total of 65 metabolites were found in the samples. 75% of samples from the hottest agro-ecological zone contained either aflatoxins, fumonisins, deoxynivalenol, zearalenone; or a combination thereof in levels exceeding European Union (EU) maximum levels, whereas the related fraction was only 17% in the cool temperature zone. Aflatoxins, citrinin, 3-nitropropionic acid, monocerin and equisetin were most prevalent and in higher levels in samples from hot agro-ecological zones, whereas deoxynivalenol, nivalenol, zearalenone and aurofusarin were most prevalent in cool agro-ecologies. On the basis of per-capita maize consumption, estimated daily intakes for all samples from hot ecologies were well above the JECFA's provisional maximum tolerable daily intake (PMTDI) of 2.0 μg/kg body weight (bw)/day for fumonisins, whereas the PMTDI of 1.0 μg/kg bw/day for deoxynivalenol was exceeded in relatively more (90%) samples from the cool highlands than the other zones. These results demonstrate the influence of micro-climatic conditions on mycotoxin prevalence patterns and underscores the need for development of agro-ecological specific mycotoxin dietary exposure management strategies.

Utility of root cortical aerenchyma under water limited conditions in tropical maize (Zea mays L.)

It has recently been shown that root cortical aerenchyma (RCA) formation substantially reduces the metabolic costs of soil exploration, thereby improving rooting depth, water capture, and plant growth under drought. The objectives of this study were to evaluate phenotypic variation of RCA formation in Malawi maize germplasm and confirm the utility of RCA formation in different agroecologies at field stations and on smallholder farms in Malawi. Forty maize accessions collected across Malawi were grown under rainfed field conditions, and a subset contrasting for RCA were grown under well-watered and water stressed conditions at two research stations and under natural drought on farms across two agroecological zones in Malawi. We found substantial variation for RCA in local germplasm ranging from 0% to 37% of root cross sectional area. Suboptimal water availability increased RCA from 54% to 77% across environments. Under water stress high RCA genotypes had 23% to 29% greater leaf relative water content, 67% to 96% greater shoot biomass 70 days after planting, and 78% to 143% greater grain yield than low RCA genotypes. Our results are consistent with the hypothesis that RCA improves plant growth under drought by reducing the metabolic costs of soil exploration and improving water acquisition. RCA has value as a selection criterion to improve the performance of maize and possibly other cereal crops in water limited environments.

Genetic diversity in Sorghum bicolor (L.) moench accessions from different ecogeographical regions in Malawi assessed with RAPDs.

Genetic variation within and among several Sorghum populations from different agroecological zones in Malawi were investigated using random amplified polymorphic markers (RAPDs). DNA samples from individual plants were analyzed using 35 oligonucleotides of random sequence. Twenty five of these primers allowed amplifications of random polymorphic (RAPD) loci. Overall, 52% of the scored loci were polymorphic. Every accession was genetically distinct. The analysis of molecular variance revealed that the within-region (among accessions) variations accounted for 96.43% of the total molecular variance. Observed variations in allelic frequency was not related to agroecological differences. The degree of band sharing was used to evaluate genetic distance between accessions and to construct a phylogenetic tree. Further analysis revealed that the sorghum accessions analyzed were genetically close despite considerable phenotypic diversity within and among them. It is suggested that all the sorghum landraces currently available in Malawi should be conserved both ex situ and in situ to maintain the current level of genetic diversity.