Glycemic Response to Oat Bran Muffins Treated to Vary Molecular Weight of β‐Glucan

Oat bran muffins, containing 4 or 8 g of β‐glucan per two‐muffin serving, were prepared with or without β‐glucanase treatment to produce a range of β‐glucan molecular weights from 130,000 to just over 2 million. Following an overnight fast, the glycemic responses elicited by the untreated and treated muffins was measured in 10 healthy subjects and compared with a control whole wheat muffin. Taken all together, the 4‐g β‐glucan/serving muffins reduced blood glucose peak rise (PBGR) by 15 ± 6% compared with the control. The 8‐g β‐glucan/serving muffins had a significantly greater effect (44 ± 5% reduction compared with the control, P < 0.05). The efficacy of the muffins decreased as the molecular weight was reduced from a 45 ± 6% reduction in PBGR (P < 0.05) for the untreated muffins (averaged of both serving sizes) to 15 ± 6% (P < 0.05) for muffins with the lowest molecular weight. As the molecular weight was reduced from 2,200,000 to 400,000, the solubility of the β‐glucan increased from a mean of 44 to 57%, but as the molecular weight was further decreased to 120,000, solubility fell to 26%. There was a significant correlation (r² = 0.729, P < 0.001) between the peak blood glucose and the product of the extractable β‐glucan content and the molecular weight of the β‐glucan extracted.     

Seed Potato Quality Improvement through Positive Selection by Smallholder Farmers in Kenya

In Kenya, seed potato quality is often a major yield constraint in potato production as smallholder farmers use farm-saved seed without proper management of seed-borne pests and diseases. Farm-saved seed is therefore often highly degenerated. We carried out on-farm research to assess whether farmer-managed positive seed selection could improve yield. Positive selection gave an average yield increase in farmer-managed trials of 34%, corresponding to a 284-€ increase in profit per hectare at an additional production cost of only 6 €/ha. Positive selection can be an important alternative and complementary technology to regular seed replacement, especially in the context of imperfect rural economies characterized by high risks of production and insecure markets. It does not require cash investments and is thus accessible for all potato producers. It can also be applied where access to high-quality seed is not guaranteed. The technology is also suitable for landraces and not recognized cultivars that cannot be multiplied formally. Finally, the technology fits seamlessly within the seed systems of Sub-Saharan Africa, which are dominated by self-supply and neighbour supply of seed potatoes.     

Quantifying the yield gap in wheat-maize cropping systems of the Hebei Plain, China

Wheat-maize double cropping is the most important cropping system on the Hebei Plain and is one of the most important cropping systems in China. In a scenario of greater food demand, and increasing water and rural labour scarcity, it is critical that the annual productivity of the system is improved in water-energy-cost efficient and low carbon ways. Based on farm surveys, this paper benchmarked the performance of wheat-maize double crops on the Hebei Plain during the 2004-2005 season. These farm yields were assessed both against experimental yields collected from on-farm maximum yield trials conducted during the same 2004-2005 season and relative to simulated estimates of the climate-driven potential productivity of the region.The survey of 362 farms in six counties of the Hebei Plain during the 2004-2005 season found wheat yields ranging from 3375 kg ha⁻¹ to 9000 kg ha⁻¹ with an overall average yield of 6556 kg ha⁻¹. Maize yields averaged 7549 kg ha⁻¹ and ranged from 3375 kg ha⁻¹ to 11,250 kg ha⁻¹. The aggregate production for the wheat-maize double crops grown in the 2004-2005 season averaged 14,105 kg ha⁻¹ across the six counties. This was 72% of the average production (19,586 kg ha⁻¹) recorded from on-farm trials conducted in each of the six counties and 60% of the simulated average production potential (24,147 kg ha⁻¹) for the Hebei Plain in the 2004-2005 season. Thus, the annual productivity of the current cropping system could be increased with currently available technologies by 28%, while a yield increase of 42% is possible if farm yields approach the simulated yield potential.Based on farmer interviews and field observations, a number of real and perceived reasons for the current yield gaps in farmers’ fields were recognised. For instance, irrigation at stem-elongation of wheat is a current recommendation, yet only a proportion of the surveyed farmers were able to follow this strategy due to lack of access to shared irrigation facilities. Improving the region's infrastructure to enable more timely irrigation of crops will be a necessary prerequisite to improved productivity.The results from the farm surveys and on-farm trials indicate that, with current recommended practices, farmers can improve their annual farm productivity and close the current yield gaps. However, the survey identified that increasing system performance and efficiency will require a focus on both agronomic and socio-economic issues.     

Site fidelity,survival and conservation options for the threatened flapper skate (Dipturus cf. intermedia)

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Habitat suitability,coverage by protected areas and population connectivity for the Siamese crocodile Crocodylus siamensis Schneider, 1801

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How Could Agricultural Land Systems Contribute to Raise Food Production Under Global Change?

To feed the increasing world population, more food needs to be produced from agricultural land systems. Solutions to produce more food with fewer resources while minimizing adverse environmental and ecological consequences require sustainable agricultural land use practices as supplementary to advanced biotechnology and agronomy. This review paper, from a land system perspective, systematically proposed and analyzed three interactive strategies that could possibly raise future food production under global change. By reviewing the current literatures, we suggest that cropland expansion is less possible amid fierce land competition, and it is likely to do less in increasing food production. Moreover, properly allocating crops in space and time is a practical way to ensure food production. Climate change, dietary shifts, and other socio-economic drivers, which would shape the demand and supply side of food systems, should be taken into consideration during the decision-making on rational land management in respect of sustainable crop choice and allocation. And finally, crop-specific agricultural intensification would play a bigger role in raising future food production either by increasing the yield per unit area of individual crops or by increasing the number of crops sown on a particular area of land. Yet, only when it is done sustainably is this a much more effective strategy to maximize food production by closing yield and harvest gaps.     

Interpretation of Climate Change and Agricultural Adaptations by Local Household Farmers: a Case Study at Bin County,Northeast China

Although climate change impacts and agricultural adaptations have been studied extensively, how smallholder farmers perceive climate change and adapt their agricultural activities is poorly understood. Survey-based data (presents farmers' personal perceptions and adaptations to climate change) associated with external biophysical-socioeconomic data (presents real-world climate change) were used to develop a farmer-centered framework to explore climate change impacts and agricultural adaptations at a local level. A case study at Bin County (1980s–2010s), Northeast China, suggested that increased annual average temperature (0.6°C per decade) and decreased annual precipitation (46 mm per decade, both from meteorological datasets) were correctly perceived by 76 and 66.9%, respectively, of farmers from the survey, and that a longer growing season was confirmed by 70% of them. These reasonably correct perceptions enabled local farmers to make appropriate adaptations to cope with climate change: Longer season alternative varieties were found for maize and rice, which led to a significant yield increase for both crops. The longer season also affected crop choice: More farmers selected maize instead of soybean, as implicated from survey results by a large increase in the maize growing area. Comparing warming-related factors, we found that precipitation and agricultural disasters were the least likely causes for farmers' agricultural decisions. As a result, crop and variety selection, rather than disaster prevention and infrastructure improvement, was the most common ways for farmers to adapt to the notable warming trend in the study region.