Evaluation of grain yield based on digital images of rice canopy

Table 7 Fitted equations for the normalized redness intensity (NRI), normalized greenness intensity (NGI), and normalized blueness intensity (NBI) values (x) and yield (y) across different growth stages of rice

Stages	NRI			NGI			NBI
Stages	Regression equations	R ²	p	Regression equations	R ²	p	Regression equations	R ²	p
TS	y = − 2E + 06x² + 1E + 06x − 188418	0.0109	0.9311	y = − 119334x² + 96588x − 12308	0.0597	0.67032	y = 245939x² − 80957x + 12745	0.0664	0.63984
PS	y = − 9E + 06x² + 5E + 06x − 783277	0.2824	0.11566	y = 2E + 07x² − 2E + 07x + 4E + 06	0.3632	0.05322	y = − 8E + 06x² + 4E + 06x − 403687	0.3531	0.05894
HS	y = − 8E + 06x² + 6E + 06x − 976732	0.1738	0.28902	y = 7E + 06x² − 7E + 06x + 2E + 06	0.226	0.18915	y = − 4E + 06x² + 1E + 06x − 73035	0.1926	0.24896
FS	y = − 9E + 06x² + 6E + 06x − 1E + 06	0.4148	0.03074	y = − 250780x² + 158991x − 10957	0.1883	0.46575	y = − 2E + 06x² + 755848x − 51130	0.293	0.10504
LFS	y = − 3E + 06x² + 2E + 06x − 434790	0.4853	0.01333	y = − 158882x² + 99109x − 5580.9	0.2439	0.10197	y = − 1E + 06x² + 436500x − 32612	0.4122	0.03163

TS, JS, HS, FS, LFS and MS indicate the tillering, jointing, heading, filling, late filling and maturity stages of rice, respectively

ISSN: 1746-4811