Variation in shoot and root characteristics and their association with drought tolerance in lentil landraces

Abstract

Lentil (Lens culinaris Medikus subsp. culinaris), generally grown as a rainfed crop, is often subjected to drought. Drought tolerance is closely related to the distribution of root systems in the soil. We studied seedling shoot and root characters in a set of eight randomly selected lentil genotypes collected from Ethiopia, India, Iran, Syria and ICARDA. Each group of genotypes represents a specific adaptation to the environmental conditions associated with its area of origin. The genotypes were evaluated during two seasons (1997)(1998)(1999) under field conditions. Thirty-five-day-old seedlings grown in pots in the open air were assessed for stem length, stem weight, taproot length, lateral root number, total root length and total root weight. Combined analyses over 2 years showed that these characters exhibited significant genotypic variability. Stem length, taproot length and lateral root number were highly correlated, both amongst themselves and with yield. High heritability estimates provided reliability in screening based on these traits. Regression analysis showed that stem length alone accounted for 85% of the variance that occurred in seed yield per plant. Cluster analysis showed that the landraces that originated in Iran and Syria, and the breeding lines developed at ICARDA are distinctly different from the lentil accessions that originated in countries at more southerly latitudes (India and Ethiopia). However, of the total of 40 genotypes, only one line (ILL 6002) was strikingly different from all other test genotypes. This line exhibited significantly superior root and shoot traits and yield, and, therefore, is a valuable germplasm for breeding drought tolerant cultivars.

Water: the most important ‘molecular’ component of water stress tolerance research

“…Silim and Saxena 1993;Tuberosa et al 2002;Matsui and Singh 2003;Ober et al 2005;Sarker et al 2005;Kashiwagi et al 2006). Most of these studies assume that rooting traits relate to water uptake.…”

Characterization of lentil (Lens culinaris M.) germplasm through phenotypic marker

“…The largest and most representative collection of lentil landraces is maintained by the International Center for Agricultural Research in the Dry Areas (ICARDA) (3351 accessions), and large collections are also held in the USA (2807 accessions), Russia (2857 accessions), Australia (2847 accessions) and Turkey (1435 accessions); (Ford et al, 2007). Several of the lentil landraces that have exhibited significantly superior root and shoot traits and yield were considered to be valuable germplasms for breeding a drought-tolerant cultivar (Sarker et al, 2005). In Bangladesh, the lentil landraces must be characterized for use of the future lentil breeding program.…”

Opportunities to improve the seasonal dynamics of water use in lentil (Lens culinaris Medik.) to enhance yield increase in water-limited environments

“…High genetic variation has been reported for root traits such as taproot length, lateral root number, total root length, and total root weight for lentil germplasm from different origins [13,14,25,26,31,42]. The high heritability estimates that were reported by these authors indicate the feasibility of making use of this genetic variability for the development of drought-adapted cultivars.…”

“…Lentil is an annual herbaceous plant with indeterminate growth exhibiting high variation in its growth habit: single stem, erect, semi-erect, compact growth or much-branched low bushy forms [13,14,31,42]. Developmental plasticity can involve one or all of these plant characteristics.…”