ALKALINE TOLERANCE OF EMERGENCE AND EARLY GROWTH OF RICE SEEDLINGS USING A PETRI DISH IN CHINA

In this study, we performed five treatments of different stages of pH, working with actual alkaline soil taken from the alkaline zone of the western part of Jilin Province, to compare the emergence and elongation of plumules of about 19 varieties of Chinese rice. In accordance with an increase in the pH of each treatment, the emergence percentages and the emergence scores which explained the growth of the plumule decreased linearly; the average emergence days increased linearly. The significant difference among varieties was observed in both emergence percentages and average emergence days except the treatment with the lowest pH. The significant negative correlation between the emergence percentages and the average emergence days; the significant positive correlation between the emergence percentages and the emergence scores were observed. A significant negative correlation between average emergence days and emergence scores was observed in all treatments. Emergence scores were low as average emergence days were large. A significant positive correlation was found, with a 0.1% level between the alkali-resistant score a1 and a2 which obtained from the regression equation between emergence percentages and pH value of each treatment as well as average emergence days and pH value of each treatment. As a result, the difference of emergence characteristics and the emergence scores can be used as the screening indexes of emergence characteristics under alkaline stress. and as a new indexes suitable for direct sowing under alkaline conditions.