Genetic Variation in Root Traits and Nutrient Acquisition of Lentil Genotypes

Abstract

Lentil (Lens culinaris L.), a pulse crop, is grown in nutrient-poor soils in many developing countries, often with little or no fertilization. Knowledge on root traits of lentil and the assessment of their role in nutrient capture would help to sustain its production in these nutrient-poor soils. Root traits (root length, root hairs, root-induced acidification, and phosphatase enzymes) of 10 lentil genotypes (Barimasur-3, (2), L-107 × 87012, L-5 × 87272 and 8406-122) were investigated and then related to the plant uptake of phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulphur (S), iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), molybdenum (Mo), and cobalt (Co) in laboratory and pot experiments. There were significant (p < 0.05) differences in root length (RL) and root-hair density (number mm −1 root) among the genotypes. The genotypes did not differ to induce rhizosphere acidification and acid phosphatase activity (aptase). Uptake of most nutrients differed significantly (p < 0.05) among the genotypes, but root length (RL) was, in general, weakly correlated to the uptake of the most nutrients in the shoot dry matter (DM). The genotypes with prolific root-hair formation (Barimasur-4 and Barimasur-3) were particularly superior in uptake of those nutrients (K, P, Fe, Mn, Cu, Zn, Mo) whose availability in soils is usually low and whose transport 643 Downloaded by [University of Connecticut] at 15:23 07 October 2014 644 T. S. Gahoonia et al.to the roots is diffusion limited. The results of this investigation, though based on a small sample of lentil accessions/cultivars, suggest that genetic variation in lentil root traits and nutrient uptake can be pronounced. Screening of a large number of local and exotic cultivars or lines of lentil should be conducted by including more root traits (N 2 fixation, organic acids, mycorrhizae) to find nutrient-efficient germplasm to promote lentil production.

Root Length and P Uptake Analysis in Five Elite Lentil (Lens culinaris Medikus) Lines Suitable for Northeast India Condition

“…These results corroborate with the results of study conducted by Gahoonia et al, (2005) in lentil and Kumar et al, (2013) in paddy.…”

“…At 65 DAS and 90 DAS genotypes G1 (DPL-62) and G3 (PL-8) had higher root length than others indicating that these genotypes have high root lengths irrespective of acidic levels and water deficit levels (Table 1). Ahmed et al, (2014) and Gahoonia et al, (2005) also reported similar findings with the present study.…”

Biotic interactions, ecological knowledge and agriculture

“…In a subsequent study, modification of wheat seeding density was much more effective at weed suppression than differences among cultivars (Lemerle et al 2004). In another work, selection of rice varieties for their allelopathic potential is being pursued (Ni & Zhang 2005) and initial results from India suggest there is potential for improving lentil root systems to increase nutrient uptake ability in low fertility soils, which may improve competitiveness against weeds (Gahoonia et al 2005(Gahoonia et al , 2006. Furthermore, some weed species produce fewer and less dormant seeds when grown among a highly competitive crop; however, seed input from less competitive areas of the field such as field margins or areas of poor crop growth could still be problematic (Nurse & DiTommaso 2005).…”

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

“…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.…”

“…Lentil, however, is commonly grown in developing countries on marginal lands with poor soil in rain-fed environments [14]. Like many other crops that grow in the Mediterranean and semi-arid zones, lentil often faces terminal drought stress during the reproductive phase as a consequence of diminishing rainfall or plant available water and rising temperatures.…”