Development of a sensor-based site-specific N topdressing algorithm for a typical leafy vegetable.

ABSTRACT: Precise and site-specific nitrogen (N) fertilizer management of vegetables is essential to improve the N use efficiency considering temporal and spatial fertility variations among fields, while the current N fertilizer recommendation methods are proved to be time- and labor-consuming. To establish a site-specific N topdressing algorithm for bok choy (Brassica rapa subsp. chinensis), using a hand-held GreenSeeker canopy sensor, we conducted field experiments in the years 2014, 2017, and 2020. Two planting densities, viz, high (123,000 plants ha^-1) in Year I and low (57,000 plants ha^-1) in Year II, whereas, combined densities in Year III were used to evaluate the effect of five N application rates (0, 45, 109, 157, and 205 kg N ha^-1). A robust relation

SUBMITTER: Ji R 

PROVIDER: S-EPMC9479683 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature