Rooting of Jatropha Curcas Cutting Types Under Different Substrates.

Fossil fuels depletion has created a pressure on the search for options to replace these fuels for similar with equal efficiency. Thus, in recent years the use of plants with potential for biodiesel production is growing, with emphasis on Jatropha curcas L. The plant is easily propagated by seeds, but originates plants with high genetic variability, which required the development of propagation techniques for application in plant breeding. This work was performed out at greenhouse condictions of the Crop Science Department of the Sao Paulo State University (UNESP) Ilha Solteira Campus to evaluate the rooting of the Jatropha curcas under treatments with different substrates and cutting types. The experimental design was the completely randomized in a 3 x 2 factorial system (substrates x cuttings) totaling 6 treatments with 3 replications of 10 cuttings each. Cuttings were apical, median and basal parts approximately 20 cm long. The staking was done in plastic pots with dimensions of 42 x 14 x 14 cm (length x width x depth) containing substrates washed sand and vermiculite. The variables analyzed after 75 days were the percentage of live and rooted cuttings, dry weight of shoots, dry weight of roots, number of shoots, length of shoots and leaves larger than 2 cm per cutting. There was an interaction between the factors for number of live and rooted cuttings and dry mass of roots. It was observed that the basal cuttings showed higher percentage of live and rooted cuttings with no difference for the type of substrate (87.5% and 82.5% in sand and vermiculite), however for the apical and middle cuttings in vermiculite was observed an increased survival and rooting, 80% and 60% respectively, when compared to sand cuttings with 47.5% and 27.5% for middle and apical cuttings respectively.