Abstract
Efficient nitrogen (N) fertilizer applications in onion (Allium cepa L.) can reduce input costs and improve fertilizer-use efficiency, while maintaining high yields and quality. Understanding the N requirements of onion at different growth stages is necessary to enhance fertilizer N-use efficiency (FNUE). In a two-year study (2021 and 2022), the FNUE of onions was determined at five stages of development (at transplant, vegetative growth, bulb initiation, bulb swelling and bulb maturation). The FNUE was estimated by substituting a conventional N fertilizer (ammonium nitrate) with a 5% enriched 15N ammonium nitrate at a rate of 22.4 kg·ha−1 N, at one of five application times corresponding to a stage of development. All onions received a season total of 112 kg·ha−1 N. Marketable yield of onions was significantly greater in 2022 compared to 2021 and FNUE was affected by application timing in both years. In 2021, the FNUE at transplant was 8.9%, increasing to 26.4% and 35.28% at vegetative growth and bulb initiation stages, respectively. At bulb swelling and bulb maturation stages, FNUE was greater than 95%. In 2022, the FNUE at transplant was 25.2%. This increased to 75.7% and 103% at vegetative growth and bulb initiation stages, respectively. Results suggest that the application of fertilizer N at transplant is inefficient due to limited plant uptake ability, while N applications during bulb initiation and swelling were the most efficient.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.