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Cultivar mixtures are suggested for low-input farming systems because they introduce functional diversity. The lack of common vetch (Vicia sativa L.) cultivars bred for and adapted to low-input farming systems raises the issue of whether the mixtures composed from varieties developed under conventional conditions can satisfy the demands of low-input agriculture. The objective of this project was to evaluate the performance of five common vetch varieties and mixtures of these varieties in a low-input system. Three-year preliminary experiments were conducted among widely adapted cultivars bred under high-input conditions to select the most productive cultivars. Thus, five common vetch cultivars and their mixtures were evaluated under low-input farming system (2007-2009). Dry matter (DM) production and crude protein content were measured for each entry. Mixture effect (ME) was calculated to measure the relative performance of a mixture over its components. Genotype main effect plus genotype x environment interaction (GGE) biplot analysis was used to assess yield and stability. It was observed that ME for DM was positive for three mixtures over environments and ranged from 0.19 to 4.63 Mg ha-1. GGE biplot analysis indicated that two of the previous three mixtures exhibited the greatest yield and stability. Crude protein values of the mixtures were at least comparable with their individual cultivar components. These results showed considerable advantages of mixing common vetch cultivars bred under high-input conditions for use in low-input farming system. [ABSTRACT FROM AUTHOR]

Thirty-six lentil varieties were evaluated under organic and conventional environment for three consecutive years in order to see whether the promising genetic material for an organic plant breeding program are different from those of a conventional system. The genetic material studied originated from various countries. In the conventional trial plots standard cultural practices (P mineral fertilization & pest control) were applied throughout the growing season, while in the organic ones no fertilizers or pest agrochemicals were applied. Significant regression, but of low value, between grain yield ranking and earliness or harvest index ranking was detected. Combined ANOVA indicated significant differences between genotypes, years, environments and genotype × environmental interactions (GEI). It was observed that under conventional management most of the genotypes had a higher yield compared to the organic one. The mean grain yield ranking of the genotypes in each of the environments revealed that some of the genotypes occupied the same ranking position at both the organic and the conventional environment (non-crossover GEI), while others exhibited a significant alteration in their ranking (crossover GEI) under the two environments. Crossover GEI and non-cross over GEI revealed two types of lentil varieties. Varieties with specific adaptation and varieties with broad adaptation. It was concluded that grain yield was in general higher when lentil varieties were grown under a conventional environment compared to the grain yield produced under an organic environment. Yet, there are lentil genotypes with a higher yielding ability under the organic management and therefore should be targeted by the breeder. [ABSTRACT FROM AUTHOR]