Phosphorus and potassium uptake, translocation, and utilization efficiency in chickpea under Mediterranean conditions

Sowing time and cultivar choice have major effects on chickpea yield in the Mediterranean climate, but the effects on nutrient requirements are not well known. Information regarding nutrient requirements and utilization efficiency by crop species is necessary to optimize nutrient management in agricultural systems. Alpha two-year field study was conducted to examine the patterns of P and K uptake, translocation, utilization and removal across a wide-range of chickpea yield levels induced by sowing time (March and April) and cultivar [Zehavit-27 (Kabuli-type), Andros, Kassos, and Serifos (desi-type)], as well as to identify plant traits associated with efficient nutrient utilization. At all samplings throughout the growing period, P uptake was significantly correlated with that of K uptake with r values between 0.633 (P < 0.05) and 0.983 (P < 0.01). Both P and K uptake peaked, in terms of uptake rate and net uptake, earlier during the April sowing (early pod filling stage) compared with March sowing (late pod filling stage). Early sowing increased chickpea productivity and total nutrient uptake, but did not offer any advantage in terms of nutrient utilization efficiency. Phosphorus or K translocation to seeds were significantly correlated with P (r = 0.838, P < 0.01) or K (r = 0.861, P < 0.01) accumulation prior to the beginning of seed filling, respectively. PUtE varied from 161 to 422 kg kg(-1) and was greater than KUtE (32-101 kg kg(-1)). Low (leaf + stem)-P or K concentration at maturity could be considered as an indirect selection tool to enhance nutrient utilization efficiency. Seed P or K removal depended on yield level of each cultivar. For a yield level of 2000 kg ha(-1), 8.2 kg P ha(-1) and 18.9 kg K ha(-1) were removed by seed harvest.