Variability in drought stress response in a panel of 100 faba bean genotypes

Abstract

Faba bean is an important protein crop for food and feed worldwide and provides a range of advantages in crop rotations. Its limited use in modern agriculture is mainly due to the high fluctuations in yield. A well known limiting factor in most legumes, and particularly in faba bean, is the high sensitivity to water shortage, which is further aggravated by climate change. The present study was undertaken to exploit the genetic variation in drought stress response in a faba bean collection of 100 accessions with diverse origins and to assess selection criteria for identifying drought tolerant genotypes. Physiological, phenological and yield related traits evaluated under drought or water-sufficient conditions responded significantly to the end-terminated drought stress. Comparison of yield relations showed the advantage of using a stress tolerance index (STI) to identify genotypes combining high yield potential with high stress yield. With regard to physiological traits, SPAD (chlorophyll content) values were significantly related to yield as well as to STI, while the other traits also contributed to different extents to variation in yield formation. Among the yield related traits, seeds per plant proved to be the most important trait followed by pods per plant. Interestingly, the eight genotypes with the best STI performance use different strategies to cope with drought stress.

Identifying Bioactive Compounds in Common Bean (Phaseolus vulgaris L.) Plants under Water Deficit Conditions

“…In our case, the number of pods per plant was the only parameter affected by deficit irrigation. These results are in concordance with several studies that affirmed that moderate drought stress may have a negative effect on the pod number per plant but no effect on the seed size or seed number per pod in bean genotypes that are tolerant to drought [43][44][45].…”