In Belgium and The Netherlands, bread wheat (Triticum aestivum L.) is getting attention within a growing movement looking for more sustainability of wheat cropping and breadmaking. The few varieties available are pure lines that do not match the wide range of environments and organic farming practices, so that yields and milling quality are often disappointing. Composite Cross Populations (CCP) have been created with the idea of evolutionary plant breeding through on-farm mass selection and seed saving. In 2015–2016, one such CCP of winter wheat was cropped side by side with a pure line variety in four organic farms with different wheat cropping practices, as a first step to answer some of the concerns arising from farmers’ networks we work with. Seeding rates ranged from the standard high to the very low ones practiced under the System of Wheat Intensification (SWI). Multivariate data analysis confirmed greater differentiation of the CCP both compared with pure line varieties and within populations on farms where inter-plant competition was less intense. Low seeding rates thus seem to enhance the phenotypic expression potential of a CCP, yet this is a neglected fact among participatory plant breeders. Since both CCP and SWI have great potential for ecological intensification within organic farming, we argue that more work is needed on finding new ways of combining innovation in farming practices and on-farm plant breeding, which also implies new ways of organising research.

The nitrogen supply can be a yield-limiting factor in organic farming, especially when reduced tillage is applied. An organic field experiment was conducted from 2007 to 2013 to analyse the potential of the nitrogen supply through the efficient use of green manure crops in different tillage systems. Three farming systems were compared: a stubble cleaner system (SC) and a plough system (PL), both in a cereal-based crop rotation, and another plough system in a crop rotation that included alfalfa grass ley (PLALF). In the fifth year of the experiment, the experimental design was extended into a split plot design, and seven green manure treatments (Lolium perenne, Phacelia tanacetifolia, Sinapis alba, a mixture of Sinapis alba and Trifolium resupinatum, Trifolium resupinatum, Vicia sativa, and bare fallow as the control) were integrated into each of the three systems. The effects of the three systems and the green manure treatments on N mineralization, the soil microbial biomass and the yield of the main crops of oats and field beans in the sixth and seventh years of the experiment were analysed. The results showed that the choice of green manure species was of minor importance in the PLALF system. This system generally success- fully supplied N to the oats with oat yields from 3.6 to 5.1 t per ha.Vicia sativa was the most promising green manure crop in the SC and PL systems, with the Nmin values and oat yields (4.0 and 4.6 t per ha) being similar to those in the PLALF system. In the subsequent year, the PLALF system again was more successful in most of the Nmin assessments than the PL and SC systems, which often had rather similar results. In addition, a main crop of field beans was able to compensate for the differences in the Nmin content, and the yields were similar in all three systems (3.1 to 3.7 t per ha). The microbial biomass in the top soil was significantly increased in the reduced tillage system compared to the plough systems. In conclusion, reduced tillage in organic farming can promote soil microorganisms and be competitive if the nitrogen supply is improved through the efficient use of green manure or an adequate leguminous main crop.

This article reports evidence for substantial public support for the large-scale deployment of three renewable energy options in Kenya: wind, solar PV, and geothermal energy. With these renewable technologies, the government of Kenya could make a large contribution to reaching its national commitment under the Paris Agreement. Prices, infrastructural needs, and land-use requirements importantly contribute to shaping public opinion about these renewable energy alternatives, in different ways and directions for wind, PV, and geothermal energy. While overall the evaluation of these technologies is positive, public authorities should be wary of the possible inconveniences and drawbacks associated with them. Anticipating and, where possible, mitigating these shortcomings in national climate and energy development plans could preclude some of them becoming possible hindrances for broad-scale adoption of wind, PV, and geothermal energy. Furthering quantitative public acceptance studies, like the one presented here based on (semi-)expert elicitation and information-choice questionnaires, can assist in Kenya fully reaching its national climate and energy ambitions. More generally, we argue that the establishment of affordable, clean, and secure energy systems, as well as the mitigation of global climate change, can benefit from stakeholder engagement and public survey analysis like the one performed in our study – in developing countries as much as in the developed part of the world.

Fermented leaf fertilizers (FLF) are made of anaerobically fermented plant and/or animal resources and principally used for foliar plant nutrition, as they provide a quick nutrient supply, especially of micronutrients. Their use is most common in horticultural production as a complementary measure to organic basal fertilization in the case of nutrient deficiencies. Since FLF are commonly made of farm residues, their formulation varies according to the available resources and the treated crops. The most common raw materials are cattle manure, cow milk, cane molasses, and water. Within Latin America, the production of FLF is popular with smallholders. Most of these farmers produce them on-farm using adapted plastic barrels as fermenters. Industrial production is conceivable. FLF have been successfully tested in banana, bean, broccoli, carrot, cucumber, lettuce, maize, papaya, and spinach production. This review highlights the principles of this sustainable and promising organic fertilization strategy, emphasizing the preparation of FLF.