Conservation agriculture (CA) practices are becoming more important in Mediterranean rainfed areas due to their potential to minimize climatic risk, reduce soil erosion, and improve soil quality and water availability. Due to minimum soil disturbance and crop residue retention, the soil environment for crop growth and development can differ between CA and conventional tillage (CT) practice. However, breeding targets for improving yield performance in CA system remain poorly explored. The objective of this study was to assess the performance of elite genotypes of barley, chickpea, lentil, and wheat grown under CA, a promising alternative agricultural practice in the Mediterranean rainfed conditions. A three-year field study, with contrasting rainfall pattern, was conducted in the International Center for Agriculture Research in the Dry Areas’s research field in Morocco to evaluate the tillage × genotype interaction and its consequence for yield performance of barley, chickpea, lentil, and wheat. Thirteen elite genotypes for each crop were planted under both CA and CT systems. Wheat and chickpea produced significantly higher grain yield (+62% for wheat and +43% for chickpea) under CA than in CT, while lentil and barley performed equally under both systems. Significant effect of tillage × genotype was more frequent for chickpea and wheat than for barley and lentil. Increased yield under CA, mainly in dry year, was associated with higher harvest index (HI). For each crop species yield was mainly influenced by rainfall amount and distribution (75–88% yield variation), and tillage × genotype was of little importance. The overall results suggest that a specific breeding program for CA in lentil, chickpea, wheat, and barley may not be efficient. Few tillage × genotype interaction, especially in dry years, indicated that breeding target on increasing HI, tolerance to drought (high yield in dry years), and potential yield (high yield in wet year) can help to improve yield performance of chickpea, lentil, and wheat genotypes in CA system. Varieties with wider adaptability considering drought tolerance, higher yield with stability, and adoption of CA practices are important in the context of the Mediterranean rainfed environment. Integrating trade-off analysis between yield potential and stability in a rainfall gradient in both CT and CA in the national certification scheme of varieties may be more efficient than developing breeding programs for each type of tillage system.

Currently, the unchecked increase in human population results in increased demand for agricultural lands. Growing two or more crops simultaneously is one of the mechanisms to reduce this problem. A field experiment was conducted in northwestern Ethiopia during 2017 and 2018 cropping seasons. Two legume crops [haricot bean (Phaseolus vulgaris) and lupine (Lupinus angustifolius)] were intercropped with finger millet (Eleusine coracana) using two intercrop planting methods (row and mixture) and three finger millet-legume planting ratios (100.0%:75.0%, 100.0%:50.0% and 100.0%:25.0% of the respective recommended seed rate of sole crops). Two sole crop finger millets (planted in rows and broadcast) and two sole legume crops (haricot bean and lupine) were included as checks. The experiment comprised a randomized complete block design with three replications. Results indicated intercropped finger millet and total land output yield from finger millet-haricot bean row intercropping at a 100:50 planting ratio and sole finger millet planted in a row improved better yield stability. Finger millet-haricot bean row intercropping at a 100:50 planting ratio also resulted in higher grain yields of the component crops, area time equivalent ratio (1.34), relative production (38.1%) and economic (314.0%) efficiencies with a relatively lower component crop competitive ratio. Thus, this cropping system offered increased productivity and economic return and is a viable option for increasing household food security.

Common bean (Phaseolus vulgaris L.) is perhaps the most important grain legume in sub-Saharan Africa (SSA) smallholder systems for food security and household income. Although a wide choice of varieties is available, smallholder farmers in western Kenya realize yields that are low and variable since they operate in risky production environments. Significant seasonal variations exist in rainfall and severity of pests and diseases. This situation is worsened by the low and declining soil fertility, coupled with low capacity of farmers to purchase production inputs such as fertilizers, fungicides and insecticides, and land scarcity. The objective of this study was to investigate whether growing multiple-bean varieties instead of a single variety can enable farmers enhance yield stability over seasons and ensure food security. Five common bean varieties were evaluated in multiple farms for 11 seasons at Kapkerer in Nandi County, western Kenya. Data were collected on grain yield, days to 50% flowering and major diseases. In addition, daily rainfall was recorded throughout the growing seasons. The five varieties were combined in all possible ways to create 31 single- and multiple-bean production strategies. The strategies were evaluated for grain yield performance and yield stability over seasons to determine the risk of not attaining a particular yield target. Results indicated that cropping multiple-bean varieties can be an effective way for reducing production risks in heterogeneous smallholder systems. Yield stability can be greatly enhanced across diverse environments, leading to improved food security, especially for the resource-poor smallholder farmers operating in risk-prone environments. Although the results show that some of the single-bean variety strategies were high yielding, their yield stability was generally lower than those of multiple strategies. Resource-poor risk averse farmers can greatly increase the probability of exceeding their yield targets by cropping multiple-bean varieties with relatively low yields but high grain yield stability. Trading-off high grain yield for yield stability might be an important strategy for minimizing bean production risks.

Sorghum is a staple food crop in Niger and its production is constrained by sorghum midge and the use of low yielding, local sorghum varieties. To improve sorghum productivity, it is crucial to provide farmers with high yielding sorghum cultivars that are resistant to midge. We evaluated 282 genotypes in four environments of Niger Republic. Alpha (0.1) lattice with two replications was the experimental design. Genotype and genotype by environment (GGE) biplot analysis was used to study grain yield (GY) stability and G × E interactions. The results revealed that two distinct mega environments were present. Genotype L232 was the best genotype for GY in the first planting date at Konni and the first and second planting dates (PDs) at Maradi. Genotype L17 was the best for GY in the second PD at Konni. The second PD at Konni was the most discriminating environment while the first PD at Konni is suitable for selecting widely adapted genotypes for GY.

Glyphosate-resistant (GR) crops have been adopted rapidly since their commercial introduction, and with the increase in commercially available crops resistant to glyphosate, continuous use of the same herbicide mode of action is now possible in some crop rotations. A 6-yr study was initiated to investigate the effects of conventional herbicides compared with continuous use of glyphosate in GR or Roundup Ready corn and GR soybean in a corn–soybean and a corn–soybean–winter wheat rotation. Individual experiments were fully phased and established at three locations under conventional tillage (CT) and at two locations under no-tillage (NT). Results indicated that midseason weed ground cover was lower when weeds were controlled with glyphosate; however, in most cases, this did not result in improved corn or soybean yields. Within locations, species richness, which strongly influenced other diversity indicators, was most affected by the herbicide treatments. Including winter wheat in the crop rotation had little effect on corn and soybean weed ground cover, density, and community structure and only affected soybean yield. Moreover, no effects of herbicide system used in previous corn and soybean were observed in winter wheat, with the exception of species diversity in NT, where species diversity tended to be greater when weeds in previous corn and soybean were treated with conventional herbicides. After 6 yr, the effects of continuous use of GR crops in rotation were similar to those reported in previous studies; however, continued monitoring and longer-term investigations of these systems are necessary to detect the early stages of development of herbicide-resistant biotypes.