Evaluation of pigeonpea [Cajanus cajan (L.) Millsp] germplasm for phosphorus use efficiency based on root architecture

Abstract

The present study was designed to assess variation in morpho physiological characteristics of diverse pigeonpea genotypes to identify promising phosphorus (P) use efficient genotypes. Forty three pigeonpea genotypes were screened in pots for their ability to acquire and utilize phosphorus under two levels of P supply i.e +P (recommended dose @40kg ha-1 P) and –P (without P). Root (volume, length, dry weight, area, perimeter, number of root tips), acid phosphatase activity (A Pase), P content of plant parts, leaf area, number of leaves and leaf dry weight related observations were recorded at 60 days after sowing. Phosphorus use efficient genotypes exhibited maximum root (length, area, perimeter, dry weight) and APase activity under -P condition. Considerable genotypic variation was found for morpho-physiological attributes, root A Pase activity and phosphorus content in plant parts. The genotypes with superior root morphological phenes, maximum APase activity and P content in leaf may have higher P acquisition and utilization efficiency under P deprived conditions.