Abstract
The development of branches of cassava (Manihot esculenta Crantz), pinhão (Jatropha pohliana Muell. Arg.) and ceara rubber plants belonging to the Euphorbiaceae was examined in Paraiba, Brazil. The number of nodes and green leaves of cassava was also observed. The number of branches on a stem ranged from 2 to 3 in cassava and ceara rubber, but exceeded 5 in pinhão. It was clearly shown that the formation of an inflorescence at the tip of a main stem or branch induced the development of branches at the uppermost nodes, and that the growth of branches started almost simultaneously with that of the inflorescence. In some plants, the inflorescence was stunted at an early stage of development. Plants with a higher order branches had a larger number of green leaves than the plants with only lower order branches. These results suggest that the development of branches contributes to photosynthesis through the increase of the leaf area. There was no difference between the primary branches at the 1st nodes (numbered basipetally) and the 2nd nodes, in the length and the number of secondary branches arising on the branch. The results of this study suggest that the development of branches should be considered in terms of flower formation.
