RICE GRAIN DARK SPOTS AND THEIR IMPACT ON QUALITY ASSOCIATED TRAITS

Abstract

Rice grain damage due to dark spots was noted more than 10 years ago in Russia. However, this phenomenon has long existed in other rice-growing countries. The factor limiting high rice yields are insect pests and pathogenic microorganisms, the vital activity of which leads to the occurrence of dark spots on the grain shells. This study hopes to assess the effects of dark spots on rice grains of six rice cultivars bred in Russia, i.e., Rapan, Khazar, Romans, Favorit, Trio, and Prestige. The study was carried out in 2020–2021 at the Federal State Budgetary Scientific Institution, Federal Scientific Rice Centre, Krasnodar, Russia. With an increase in the content of damaged grains from 5% to 10% and 20%, the mass of 1000 absolutely dry grains, vitreosity, and head rice content decrease, the filminess increased, and the content of damaged grains negatively affecting the quality traits of rice grains. If the content of damaged grains is up to 5%, grain quality decreases giving no impact of the parameter. The need to predict rice grain yield and quality based on grain damage intensity caused by dark spots ensures the profitability of growing various cultivars in rice production.