Resumo em Inglês:

A study was made of the chemical composition of samples of the ribbons taken from the rami stalks at successive stages of growth with the object of determining the percentage oí lignin, cellulose, pectin, pentosans and of some substances not belonging to the cell wall. After an initial decrease, the percentage of ash increased as the plant grew and matured. The maximum (17,5%) was reached when the plant was 105 days old. The percentage of cellulose increased regularly and reached a maximum (38,2%) when the plant was 75 days old. Subsequently there was a decrease as the plant grew older. After an initial increase, the percentage of lignin decreased somewhat and again increased as the plant matured. The maximum (14,5%), however, was observed when the plant was 45 days old. The percentage of pectin (galacturonic acid) was maximum (22,9%) in the first stage, afterwards showed a nearly regular decrease as the plant developed, but in the last two stages (105 and 120 days) there was a small increase. The percentage of pentosans (calculated of the furfurol phloroglucide yielded by pentosans only, with the Tollens'Tables), as well as the percentage of reducing sugars increased regulaily as the plant grew older. The maximum was 5,2 and 3,8 percent respectively. The percentage of hot-water extractive after a decrease in the earlier stages of the plant growth increased and reached a maximum (24,2%) in the penultimate stage of its development. The percentage of ethanol-benzene extractive from a maximum (8,3%) decreased regularly as the plant developed, but in the last stages of its development it increased somewhat. The percentage of crude protein (N x 6,25) irom a maximum (15,2%) in the first stage showed a regular decrease, but in the last two stages of the plant development there was an increase.

Resumo em Inglês:

The preliminary work with vegetables was described and special reference was-made to the group Brassica oleracea. a) Plants flowering easily in Piracicaba and probably in the whole State of São Paulo. To this group belongs the lettuce, endive, chichory, carrot, radish, kale, brocoli and cauliflower. b) Plants where special treatment is necessary for flowering, as cabbage. c) Plants that did not flower up to this moment, as Svisschard beet and beet. Three main factors contribute for the seedless condition in the group cabbage : lack of flowering, anormalities of the flowers and self-sterility. The preliminary experiments in controling these factors seem to indicate the possibility of seed production in this group. The systematics of the two species Brassica oleracea (Europe) and Brassica juncea (Oriental Asia) was discussed. The economical differences in the group Brassica oleracea are controled by Mendelian factors with complicate types of interaction. It is not necessary to look for special places in the State of São Paulo for vegetable experiments but the possibility of better results in the future, with appropriate conditions, is emphasized.