Effects of integrated nitrogen fertilization and irrigation systems, rootstocks, and cultivars on productivity, water and nitrogen consumption, and mineral nutrition of pear

Abstract

Water and nitrogen (N) management are key factors for sustainable pear production in many areas. Effects of integrated N fertilization and irrigation systems, rootstocks, and cultivars on pear ( Pyrus communis ) mineral nutrition, irrigation water and N consumption, and fruit productivity were investigated on a fine sandy loam soil at Hood River, Oregon from 2005 through 2007. Nitrogen application reduced to 80% of the current broadcast application rate and fertigated in five equal split applications could supply bearing pear trees with adequate N nutrition without reducing soil N reserves. Shifting from the broadcast of dry N fertilizer on soil surface and micro sprinkler irrigation system (BSS) to the split N fertigation and drip irrigation system (FDS) did not affect tree growth, fruit yield, or fruit size of pear. However, FDS produced more Bartlett fruit in color categories of 390 - 417 and 417 - 496 nm than BSS. Irrigation water consumption was reduced by 42.0% to 78.3%, but water use efficiency was enhanced by 51.0% to 264.2% with FDS relative to BSS. Split N fertigation and drip irrigation system may be used as an alternate N fertilization and irrigation system on bearing pear orchards to reduce irrigation water and N consumption in Hood River and other similar areas.