RELATIONSHIP OF INTERNODE-SPECIFIC WEIGHT AND WATER-SOLUBLE CARBOHYDRATES IN WHEAT

The water-soluble carbohydrate concentration (WSC) of the peduncle and the penultimate internode was determined for the main stem of tall (rhtrht) and semidwarf (Rht1Rht1) 'Maringa' spring bread wheat (Triticum aestivum L.) under well-watered and droughted glasshouse conditions. The WSC concentration of the peduncle was greater than that of the penultimate internode in most cases. The concentration of WSC was greater in well-watered than in droughted conditions. Under well-watered conditions, the two genotypes exhibited similar patterns of WSC concentration from anthesis to 18 days post-anthesis. However, they showed contrasting patterns over the same period in droughted conditions. The specific weight of the peduncle and the penultimate internode at anthesis was negatively correlated with their WSC concentration under well-watered (−0.94) and under droughted conditions (−0.64).