Determining nitrogen topdressing rates in accordance with actual seedling density and crop nitrogen status in direct-seeded rice.
J Sci Food Agric
; 104(4): 2294-2302, 2024 Mar 15.
Article
en En
| MEDLINE
| ID: mdl-37947790
ABSTRACT
BACKGROUND:
Adjusting nitrogen (N) input based on actual seedling density (ASD) and plant N status is a practical approach for improving the yield stability of direct-seeded rice. However, the adjustment of topdressing N rates has been empirical in the past. This study aimed to establish a quantitative approach for determining N topdressing rates during tillering (Ntil ) and panicle development (NPI ) based on ASD and crop N status in direct-seeded rice. Field experiments were conducted involving 12 treatments, consisting of four Ntil and three seeding rates in 2017, and eight treatments combining seeding rate, Ntil , and NPI in 2020.RESULTS:
Linear regression analysis revealed that the tiller number at panicle initiation (TILPI ) was predominantly influenced by ASD and Ntil . The determination coefficients (R2 ) of the regression models ranged from 0.887 to 0.936 across the four-season experiments. The results indicated that Ntil could be determined accurately using ASD and the target maximum tiller number. Similarly, grain yield was influenced significantly by the N uptake at panicle initiation (NUPPI ) and NPI , with R2 of 0.814 and 0.783 in the early and late seasons of 2020, respectively. This suggested that NPI could be calculated based on NUPPI and the target grain yield.CONCLUSION:
The findings offer a quantitative method for establishing N topdressing rates for tillering and panicle development, relying on the monitoring of actual seedling density and plant N status in direct-seeded rice production. © 2023 Society of Chemical Industry.Palabras clave
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Oryza
/
Plantones
Idioma:
En
Revista:
J Sci Food Agric
Año:
2024
Tipo del documento:
Article