Effects of vegetal protein hydrolysate application method, nitrogen level, and nitrate-to-ammonium ratio on growth and composition of hydroponic lettuce
Author(s)
Date Issued
2025
Type
article
Volume
105
Issue
1
Start Page
599
End Page
610
Abstract
Vegetal-derived protein hydrolysates (PHs) have been recognized as sustainable biostimulant products due to their beneficial effects on crops. However, most studies on PHs have been conducted at a fixed ratio of nitrate-to-ammonium (NO3 -:NH4 +) without considering other N application scenarios, leading to inconsistent results among the studies. This study compared the influences of N levels (2 or 10 mM N), NO3:NH4 ratios (100:0, 75:25, 50:50, or 25:75), and PH application methods - control, foliar spray (PH-F) or root application (PH-R) - on the yield, morphology, nutrients, and nutraceutical quality of hydroponic lettuce.