Differential responses of root system and gas exchange in contrasting tomato genotypes under phosphorus starvation

Abstract

Phosphorus (P) is an essential macronutrient for the development of plants. Although it is not always required in larger amounts, its presence is often limited, since the Brazilian and other soils of the world are generally poor in this element. The objective of the research was to evaluate the development of the root system, gas exchange and efficiency in the absorption of phosphorus in contrasting tomato genotypes. The experimental design was a randomized block in the factorial scheme with three tomato genotypes (Globonnie, Tom-598 and F1) and four phosphorus levels (0.2, 30, 60 and 100 mg L-1) with four replications. Assessing the root morphology, it was observed that the Globonnie genotype has higher root length value in 0.2 mg L-1 of P; however, with the increasing of P levels it was greater in F1 genotype. This study concluded that Globonnie and F1 presented better performances under phosphorus starvation, due to better root characteristics and gas exchange that promote higher P efficiency. Besides, they may further uptake and improve the use of the phosphorus. Here, we revealed a possible reduction of phosphorus and consequently production costs in tomato farming.