Production, gas and biochemical exchanges in pear cultivated in semi-arid region under different irrigation managements¹

Produção, trocas gasosas e bioquímicas em pereira cultivada no semiárido sobre diferentes manejos de irrigação

HIGHLIGHTS:

Pear gas and biochemical exchanges are optimized under irrigation depths between 85.64 and 98.50% crop evapotranspiration.

Pear production is optimized under drip and microsprinkler irrigation systems with a depth of 91.8% crop evapotranspiration.

Excess water with water depths over 120% ETc impairs pear performance, reducing photosynthetic rates and production.

ABSTRACT

The objective of this study was to evaluate the influence of irrigation systems and water depths on physiological, biochemical and production processes of pear trees grown in the Brazilian semi-arid region. The experimental design was randomized blocks, with 2 × 4 factorial scheme, corresponding to two irrigation systems (drip and microsprinkler) and four irrigation depths (60, 80, 100 and 120% of the crop evapotranspiration - ETc), with four replicates. Water deficit and excess applied to plants are harmful to gas exchange as well as to biosynthesis and accumulation of carbohydrates, amino acids and proteins in leaves, compromising the cultivation cycle of pear plants grown in the Sub-Middle São Francisco region. The irrigation depth of 91.8% ETc promotes the highest production of pear (18.49 kg plant^-1) under drip and microsprinkler irrigation systems, under the edaphoclimatic conditions of the Sub-Middle São Francisco region.

Key words:
Pyrus communis L.; localized irrigation; irrigation depths; plant science