Cassava Weed Management Data

The ‘Sustainable Weed Management Technologies for Nigeria’ was a 5-year project that was developed and assessed with smallholder farmer participation modern, relevant and appropriate cassava weed management technologies suitable for sustainable intensification in major agro-ecological (humid rainforest, forest transition savanna and southern Guinea savanna) and socio-economic conditions of Nigeria. An important goal of the project was to help smallholder cassava growers achieve sustainable increases in their productivity and incomes through the development and adoption of improved weed control methods. The project evaluated enhanced cassava agronomy, including judicious, safe use of herbicides, toward improved weed management, across 4 states in Nigeria where cassava is central to food security and livelihoods of 4.5 million farm families.

Though Nigeria is still the global leader in the overall production of cassava with about 50 million tons on 3.8 million hectares, average yields in Nigeria are only about half of those in leading countries in Asia, and less than half of those typical from researcher-run trials in Nigeria. Diverse factors are responsible for low productivity on about 4.5 million cassava farms, but poor weed management is generally among the principal factors. Weed control in the humid tropics is always a challenge, but compared to most other field crops, weed control in cassava systems is much more demanding. The crop is in the field for a long time (12 to 18 months), and is sown at wide spacing, resulting in ample opportunity for weeds to occupy space under the cassava canopy and reduce productivity. Although weeds are one of the most important constraints to improving cassava productivity; for high yields, good weed control needs to be coupled with improved varieties sown in the right densities at the right time. Adequate plant nutrition and pest control are also important; however, such inputs will not result in better yields if weeds are not controlled.

Hand weeding is the predominant weed control practice on smallholder cassava farms. Conventionally, farmers weed cassava three times, but in cassava farms where perennial weeds, such as Imperata, are predominant, extra hoe weeding may be required. Weeding takes 50 to 80% of the total labor budget. Up to 200-500 hours of labor for mostly women and children per ha are needed to prevent economic cassava root losses in Nigeria.
IITA and its partners are therefore, through this project conducted research that developed innovative weed management practices, combining improved varieties, proper planting dates, plant populations, and plant nutrition, all coupled to intercropping and tillage options, through well-focused trials in the three agro-ecologies where cassava dominates in Nigeria. Herbicides, meeting globally accepted conventions and safety thresholds appropriate for smallholders, were tested for efficacy and economic merit. Multi-location on-station/off-station trials were followed with participatory farmer evaluations. Extension manuals and other tools for farmer and applicator learning were developed.

Results from this project showed that with appropriate weed management couple with best cassava agronomy cassava growers in can more than double the national yield average in Nigeria.

Data from: Exercise plasma metabolomics and xenometabolomics in obese, sedentary, insulin-resistant women: impact of a fitness and weight loss intervention

Insulin resistance has wide-ranging effects on metabolism but there are knowledge gaps regarding the tissue origins of systemic metabolite patterns, and how patterns are altered by fitness and metabolic health. To address these questions, plasma metabolite patterns were determined every 5 min during exercise (30 min, ~45% of V̇O2peak, ~63 W) and recovery in overnight-fasted sedentary, obese, insulin resistant women under controlled conditions of diet and physical activity. We hypothesized that improved fitness and insulin sensitivity following a ~14 wk training and weight loss intervention would lead to fixed workload plasma metabolomics signatures reflective of metabolic health and muscle metabolism. Pattern analysis over the first 15 min of exercise—regardless of pre- vs. post-intervention status—highlighted anticipated increases in fatty acid tissue uptake and oxidation (e.g., reduced long-chain fatty acids), diminution of non-oxidative fates of glucose (e.g., lowered sorbitol-pathway metabolites and glycerol-3-galactoside [possible glycerolipid synthesis metabolite]), and enhanced tissue amino acid use (e.g., drops in amino acids; modest increase in urea). A novel observation was that exercise significantly increased several xenometabolites (“non-self” molecules, from microbes or foods), including benzoic acid/salicylic acid/salicylaldehyde, hexadecanol/octadecanol/dodecanol, and chlorogenic acid. In addition, many non-annotated metabolites changed with exercise. Although exercise itself strongly impacted the global metabolome, there were surprisingly few intervention-associated differences despite marked improvements in insulin sensitivity, fitness, and adiposity. These results, and previously-reported plasma acylcarnitine profiles, support the principle that most metabolic changes during sub-maximal aerobic exercise are closely tethered to absolute ATP turnover rate (workload), regardless of fitness or metabolic health status.

Supporting Materials include graphs of blood patterns of metabolites in adult women during a sub-maximal exercise bout and recovery period, and primary data in spreadsheet format on model performance, exercise and recovery, and correlation statistics for metabolites.

Journal information — Am J Physiol, Endo & Metabolism, Exercise plasma metabolomics and xenometabolomics in obese, sedentary, insulin-resistant women: impact of a fitness and weight loss intervention.

Data from: A life cycle assessment of the environmental impacts of a beef system in the USA

Purpose: The need to assess the sustainability attributes of the United States beef industry is underscored by its importance to food security locally and globally. A life cycle assessment (LCA) of the US beef value chain was conducted to develop baseline information on the environmental impacts of the industry including metrics of the cradle-to-farm gate (feed production, cow-calf, and feedlot operations) and post-farm gate (packing, case-ready, retail, restaurant, and consumer) segments.

Methods: Cattle production (cradle-to-farm gate) data were obtained using the integrated farm system model (IFSM) supported with production data from the Roman L. Hruska US Meat Animal Research Center (USMARC). Primary data for the packing and case-ready phases were obtained from packers that jointly processed nearly 60% of US beef while retail and restaurant primary data represented 8 and 6%, respectively, of each sector. Consumer data were obtained from public databases and literature. The functional unit or consumer benefit (CB) was 1 kg of consumed, boneless, edible beef. The relative environmental impacts of processes along the full beef value chain were assessed using a third party validated BASF Corporation Eco-Efficiency Analysis methodology.

Results and discussion: Value chain LCA results indicated that the feed and cattle production phases were the largest contributors to most environmental impact categories. Impact metrics included water emissions (7005 L diluted water eq/CB), cumulative energy demand (1110 MJ/CB), and land use (47.4 m2a eq/CB). Air emissions were acidification potential (726 g SO2 eq/CB), photochemical ozone creation potential (146.5 g C2H4 eq/CB), global warming potential (48.4 kg CO2 eq/CB), and ozone depletion potential (1686 μg CFC11 eq/CB). The remaining metrics calculated were abiotic depletion potential (10.3 mg Ag eq/CB), consumptive water use (2558 L eq/CB), and solid waste (369 g municipal waste eq/CB). Of the relative points adding up to 1 for each impact category, the feed phase contributed 0.93 to the human toxicity potential.

Conclusions: This LCA is the first of its kind for beef and has been third party verified in accordance with ISO 14040:2006a and 14044:2006b and 14045:2012 standards. An expanded nationwide study of beef cattle production is now being performed with region-specific cattle production data aimed at identifying region-level benchmarks and opportunities for further improvement in US beef sustainability.