THIOPHENE SYNTHESIS AND DISTRIBUTION IN YOUNG DEVELOPING PLANTS OF TAGETES-PATULA AND TAGETES ERECTA

Thiophene synthesis and accumulation were investigated in organs of Ta getes patula and T. erecta. Thiophene accumulation started rapidly in germinating seedlings of both species. Roots and hypocotyls were the m ajor thiophene accumulating organs and 5-(3-buten-1-ynyl)-2,2'-bithien yl (BBT) and 5-(4-acetoxy-1-butynyl)-2,2'-bithienyl (BBTOAc) were the major accumulated compounds. Higher thiophene concentrations were reac hed in Tagetes patula than in T. erecta. Accumulation patterns for ind ividual thiophenes were different within organs, between organs and be tween both species. Within hypocotyls of Tagetes patula, thiophene con centrations were high in the epidermis and the vascular tissue and low in the parenchymatic tissues of cortex and pith. Synthesis of thiophe nes was high in the roots and hypocotyls and very low in the leaves. T ransport of thiophenes from the roots into the shoot occurred, but the rate of transport was too low to explain the high concentrations in t he hypocotyl. It is concluded that for the main part thiophenes are ac cumulated where they are synthesized.