CHANGES IN RESPIRATION, PROTEIN AND CARBOHYDRATES OF TULIP TEPALS ANDALSTROEMERIA PETALS DURING DEVELOPMENT

Respiration, fresh and dry mass, protein and carbohydrate concentratio ns were measured in tulip tepals and Alstroemeria petals during expans ion and senescence. Tepal and petal dry-mass increased to maximum valu es by the rime the flowers were fully opened and then decreased during senescence. Fresh-mass increases were proportional co dry-mass increa ses during the early stages of development, but were more rapid as the tissues matured. In both tepals and petals, a large, rapid increase i n respiration per unit dry-mass was observed prior to flower opening a nd complete biomass accumulation. Respiration had decreased 23 and 30 %, in tepals and petals, respectively, by the rime che flower had full y opened. Respiration per unit protein also increased, but the maximum rate in both species occurred when the flower was fully opened. Respi ration decreased during senescence. Protein concentration in tepals in creased and then decreased during development, while protein decreased in petals. Glucose, the dominant carbohydrate in tepals, decreased du ring development. Starch was the dominant carbohydrate in petals and d ecreased in association with increased glucose and fructose concentrat ions. Mass-based respiration was positively correlated with absolute g rowth rate and protein concentration in developing tepals, bur no corr elations were observed in Alstroemeria petals.