The increase the productivity of some rice varieties (Oryza sativa L.) By using growth regulator foliar application.

Amino acids are crucial plant compounds that play a vital role in protein synthesis, nitrogen distribution, and signaling molecules. This study was conducted over the 2021 and 2022 seasons at the Experimental Farm of the Rice Research Department at Sakha Agriculture Research Station in Kafr El-Sheikh, Egypt. The aim was to study the beneficial effects of various levels (0.7, 1.4, and 2.1 ml/L) of foliar application of Viusid Agro, a growth regulator compound, on morpho-physiological and yield characteristics compared to a control treatment.The results pointed to the existence of a significant effects between the concentrations of the growth regulator (Viusid Agro) and rice genotypes in all the studied traits. The highest values for growth, yield, and its components were recorded with the highest foliar concentration (2.10 ml/L), while the lowest values were obtained with the lowest foliar concentration (0.7 ml/L) for yield and its components. Agronomic Efficiency kg kg-1, a measure of field efficiency, indicated that the highest efficiency was achieved when Viusid Agro sprayed at 2.10 ml/L on the Sakha 101 variety, with a value of 12.580 kg kg-1. This was followed by 2.10 ml/L spraying on Sakha 104, which compensated to 8.042 kg kg-1, surpassing the control treatment. In conclusion, this study demonstrated the potential of increasing rice productivity in terms of grain yield and its component traits by foliar application of Viusid Agro at a rate of 2.10 ml/L for the two rice varieties Sakha 101 and Giza 178 under the experimental conditions.