Carbon Assimilation and Translocation in Soybean Leaves at Different Stages of Development

摘要: Carbon assimilation, translocation, and associated biochemical characteristics of the second trifoliolate leaf (numbered acropetally) chamber-grown soybean, Glycine max (L.) Merr., plants were studied at selected stages development during period from 10 to 25 days postemergence. Leaves uniform age on basis plastochron index (LPI). The test reached full expansion (A ) maximum CO 2 exchange rates a area 17 postemergence (LPI 4.1). Maximum carbon per unit dry weight lamina attained several earlier declined as specific increased. Chlorophyll soluble protein continued increase beyond attainment A , but not accompanied by further increases in photosynthetic rates. Much fixed leaves is partitioned between starch sucrose. Starch content percentage end an 11-hour photoperiod was taken indication potential energy reserve accumulated leaf. levels same regardless 0.3 7 after attaining . Respiratory synthetic activity decreased considerably period, suggesting that accumulation entirely controlled demands Sucrose increased steadily corresponding sucrose phosphate synthetase (EC 2.4.1.14) translocation may have important regulatory role photosynthate partitioning translocation.