The supplementation of nitrogen can be increased by the use of nitrogen-fixing, diazotrophic bacteria such as Azospirillum brasilense. These bacteria can act to promote plant growth in various plant species, including corn (Zea mays L.). However, there is a need to understand the behavior of these bacteria in different agricultural systems. The objective of this study was to evaluate the effect on the growth and yield of corn inoculated with A. brasilense, and to identify the type of farming system which benefited most from the use of A. brasilense-based inoculants. The experiment conducted over two corn crop seasons was arranged in a 6 × 2 factorial scheme, consisting of six farming systems and the presence or absence of inoculation with the bacteria A. brasilense. The farming systems were derived from a long-term experiment with different fertilization systems that has been conducted since 1984. Among these systems, there were three conventional systems (CNT1: conventional no-till without fertilizer; CNT2: conventional no-till with 150 kg ha−1 of mineral fertilizer + 50 kg ha−1 of urea; CNT3: conventional no-till with 300 kg ha−1 of mineral fertilizer + 100 kg ha−1 of urea), and three organic systems (ONT1: organic no-till with 40 m3 ha−1 of organic compost; ONT2: organic no-till with 20 m3 ha−1 of organic compost; ONT3: organic no-till with 40 m3 ha−1 of organic compost and intercropped with Canavalia ensiformis). Although the Azospirillum population in the soil before planting was the same for all six systems, the count in the rhizospheric soil was higher in the organic systems, and there was no increase in that count due to inoculation. In this study, the only difference observed was within the CNT1 system, between the inoculated (CNT1-I) and uninoculated (CNT1-NI) treatments. In this system, inoculation resulted in an increase in plant height, in addition to higher concentrations of foliar N and P, and a higher plant survival rate, which culminated in higher yield. Corn inoculated with A. brasilense in the CNT1-I treatment showed a significant increase in yield—2839 kg ha−1 higher than that recorded for CNT1-NI. This study shows that, in the conventional low input treatment CNT1-I, inoculation with A. brasilense resulted in an increase in corn growth and yield.

Exclusion netting systems are effective in various contexts and are increasingly used to control crop pests. However, factors affecting pollination management under nets are poorly known. The pollination effectiveness of commercial bumble bee hives of Bombus impatiens Cresson (Hymenoptera: Apidae) was studied for apple production under exclusion netting systems in a research orchard located in Quebec, Canada during 2016–2017. Sixteen single-row plots of apple trees (plot length: 18.5 m, cultivar GingerGold) were subjected to one of the following four treatments during bloom: (1) introduction of a bumble bee hive placed at the end of the row, under nets; (2) introduction of a bumble bee hive placed in the middle of the row, under nets; (3) negative control with no pollinators, under nets and (4) agronomic control with nearby bee hives (<50 m), without nets. Resulting post-harvest fruit quality (e.g., fruit weight, size, number and distribution of seeds) was evaluated, as well as correlations between bumble bee visitation rates and fruit quality parameters were evaluated. Results suggest that bumble bees provided adequate pollination under exclusion netting systems and that resulting fruit quality was equivalent to that of apple fruit conventionally pollinated by honey bees and wild bees community (bumble bees and other bees) in the orchard environment. Positioning bumble bee hives in the middle of the row provided better fruit load homogeneity in pollinated trees. Additional discussion on bumble bees as apple pollinators and on pollen distribution methods is also included.

Feeding monogastric livestock in organic agriculture is challenging due to several tradeoffs between animal welfare aspects, resource efficiency, as well as ecological and social sustainability. Organic standards may even increase such conflicts, as is currently the case with upcoming new regulations regarding restrictions of feed sources for organic pigs in Europe. In order to contribute data for balancing reasons to minimize tradeoffs, we compared four different piglet diets, each targeted to reach a high protein quality by either a high proportion of soybean cake (SOY), inclusion of milk powder (MILK), fermentatively produced lysine (LYS) or conventional potato protein (POT). All diets were designed to meet the nutritional requirements of piglets in the best possible way, however they all represented different conflicts with either organic regulations or sustainability goals. In each of five consecutive runs, respectively three litters were assigned to every dietary treatment, resulting in 15 litters per treatment in total. In each litter, seven focus animals were defined. The piglets were studied from birth until 58 days of age. They were weaned at day 46 and sold from the farm at day 58. Piglets were individually weighed at an average age of 3, 21, 43, 50 and 58 days with simultaneous assessment of body condition score (BCS) and prevalence of diarrhea. Feed intake (FI) was recorded litter wise weekly, starting from week three. Feed conversion ratio (FCR) was calculated for the period after weaning. Statistical analysis was executed using linear mixed effect models. Regarding FI, FCR and daily weight gains, no treatment effect was found. Only at day 21, BCS was lower for piglets receiving POT. Prevalence of diarrhea increased after weaning for all treatments. All four tested diets led to similar weight gains and feed conversion in the piglets. Animals fed diet POT recovered better from diarrhea compared to the other treatments. A high soybean cake content or lysine supplementation in the diet was disadvantageous with regard to the occurrence of diarrhea. LYS diet led to signs of threonine deficit, indicating that lysine addition alone may not solve the issue. The addition of milk powder provided no extra benefit. In recognition of the health benefits, the use of 5% potato protein, even if it is sourced from conventional production, must still be considered as a sustainable option for feeding organic piglets. The sustainability implications are discussed in the paper.

The success of sustainable Theobroma cacao (cocoa) production depends on the physical and chemical properties of the soils on which they are established but these are possibly moderated by the management approach that farmers adopt. We assessed and compared soil physico-chemical properties of young, mature and old organic and conventional cocoa agroforestry systems at two depths (0–15 and 15–30 cm) and evaluated the production of cocoa pods, banana and plantain in the two farm types. Cocoa farms under organic management had 20, 81, 88 and 323% higher stocks of soil organic carbon, P, Mn and Cu, respectively, compared to those under conventional management. Higher soil moisture content, electrical conductivity and pH were found on organic systems than the conventional farms. Annual cocoa pod production per tree was similar in both cocoa systems (Org. 10.1 ± 1.1 vs Con. 10.1 ± 0.6 pods per tree). The annual production of banana and plantain was higher on organic farms (186.3 ± 34.70 kg ha−1 yr−1) than conventional systems (31.6 ± 9.58 kg ha−1 yr−1). We concluded that organic management of cocoa agroforestry systems result in soils with the greater overall quality for cocoa production than conventional management and it increases the yield of co-products. Studies focusing on the impact of organic management on cocoa agroforestry systems at the landscape and regional scales are urgently needed to further deepen our understanding and support policy.

Despite increasing land degradation in sub-Saharan Africa, investment in sustainable land management (SLM) remains low. Empirical evidence show that smallholder farmers tend to prioritize investing in SLM practices with short-term turnover—e.g., composting and crop residue integration—in order to improve soil fertility and yields to the neglect of practices like agroforestry whose benefits tend to materialize in a relatively longer period. While it is crucial for farmers to prioritize both short-term and long-term SLM practices for the maintenance of overall ecosystem health, the factors that shape the concurrent adoption of short-term and long-term SLM practices remain underexplored. Using data from a cross-sectional survey with smallholder farming households (n = 512) in Malawi, we employed logistic regression to examine the determinants of the concurrent adoption of short-term and long-term SLM practices. Our findings show that plot size, farmer-to-farmer knowledge sharing, presence of a chronically ill person in the household, active household labor size, wealth and women's autonomy are noteworthy determinants. A unit increase in plot size was associated with increased odds (OR = 1.41, p < 0.01) of simultaneously adopting short-term and long-term SLM practices. Similarly, a unit increase in the active labor size of the household (OR = 1.30, p < 0.001) was positively associated with the concurrent adoption of short-term and long-term SLM practices. Households with no chronically sick person were 3.2 times more likely to adopt short-term and long-term SLM practices simulataneously compared to those with chronically sick persons. Farming households that exchanged farming information (OR = 2.50, p < 0.001) with other households had significantly higher odds of adopting short-term and long-term SLM practices concurrently than those that did not share farming information. Compared to households in the poorest wealth category, those in the richer (OR = 3.14, p < 0.001) and richest (OR = 3.64, p < 0.001) wealth categories were both significantly more likely to adopt short-term and long-term SLM practices concurrently. These findings suggest that initiatives targeted at promoting the holistic adoption of SLM practices—a combination of both short-term and long-term practices—must pay attention to contextual nuances including household wealth, gender, farmer training and land access dynamics.

Two fungal inoculants are commercially available in Canada and the USA that target improving plant access to soil phosphorus (P). Arbuscular mycorrhizal fungi and Penicillium bilaiae were used to inoculate wheat, lentil and flax grown in an organically-managed and a conventionally-managed soil. A second crop was grown after freezing the soil to evaluate if the inoculants carried over to a second crop. Crops in the organically managed soil were smaller and took up less P than the same crop in the conventionally managed soil. Inoculation with either inoculant improved shoot growth and P uptake in wheat grown in the organically-managed soil and in lentil grown in the conventionally-managed soil. Co-application of the inoculants was never superior to the single inoculants. Carry-over effects were slight and inconsistent.

Reducing adverse environmental consequences of modern industrial agriculture requires an ecological transition of agricultural practices. An important determinant of adoption of new agricultural practices by producers is the perceived profitability of these practices. The profitability of ecological agricultural practices tends to rely on improved crop prices and reduced input use. Transition to such practices often entails increased profit volatility (risk) and long-term returns (temporal profile). Ideal candidates for transition would therefore be aware of the output price and input costs dimensions of their profitability, as well as willing to assume some risks and show patience to value long-term returns. We assessed the potential for such a transition along these three dimensions (profitability, risk aversion and time preferences) in a group of soybean producers in the agricultural frontier of the Brazilian Amazon. Primary data were collected using a questionnaire and economic tests in the region of Santarém (State of Pará, Brazil). We found that, while these producers have a low-risk aversion that could favor the adoption of new ecological practices, their focus on increasing yields to enhance profits and their high discount rates considerably reduces their propensity to adopt these practices.

The goal of this study is to perform a comparative analysis of agroecological and conventional small coffee farms. We investigated 15 coffee farms in the East region of Minas Gerais, a Brazilian rural region, based on coffee production using a multicriteria analysis with economic, social and environmental factors. The results suggest that agroecological farms perform better than conventional farms in terms of sustainability, reduce labor intensity and improve income stability and the environmental impact, such as agro-biodiversity and forest cover. In particular, the results reveal that agroecological farms, though they have lower levels of coffee productivity than conventional farms, perform better in terms of income stabilization. This result depends on product diversification (such as agri-food products, vegetables or fruits) for local markets, which reduces farmer risks associated with coffee price volatility, improving both the local economy and local food security. Moreover, agroecological farms rely more on labor than capital. Overall, the results of this study reveal that agroecological systems support the socio-economic sustainability of the rural areas under study and suggest the potential of agroecology to boost sustainable development in the East Region of Minas Gerais. In short, the spread of agroecological systems could improve local employment conditions, reducing migration toward large cities and shanty towns in other parts of Brazil. Hence, agroecology systems can represent the main alternative to conventional production systems to improve the well-being and wealth of rural populations in developing countries. The analysis presented in this study is based on a specific case study, but the rural area under study has many similarities with other areas in Latin America regarding all aspects of economic, social and environmental sustainability. Finally, some agricultural policy implications are discussed.

Agriculture is a large source of greenhouse gas (GHG) emissions but changing management practices to those more beneficial to the environment could help mitigate climate change as long as they are economically and environmentally viable. This study examines the environmental (public) and economic (private) effects of adopting ten different beneficial management practices on a representative corn farm in Ontario, Canada. The study integrates changes in GHG emissions in carbon equivalents (CO2e) and changes in profit from changes in costs and revenues in two dimensions to reveal the scope and scale of different kinds of practices. 4R nitrogen management practices are smaller in scale compared to cropping practices and, therefore, have smaller potential costs and benefits. Land use changes, from practices including biomass, afforestation, crop rotation and cover cropping, have larger impacts on soil sequestration and carbon-equivalent GHG reduction, but with significantly greater costs. Seven practices were found to, at least partially, be economically and environmentally beneficial. The adoption of no-till and N-rate reduction is firmly positive, whereas the production of biomass has the largest potential economic and environmental gains. Crop rotation and diversification and cover cropping can be mutually beneficial, as can changing N-application practices. The use of inhibitors may be economically beneficial if yield gains outweigh purchase costs.