Seed morphometry, in vitro germination and vegetative propagation in sacha inchi (Plukenetia volubilis L.)

The aims of this study were to analyze the in vitro germination, seed germination processes and determine the best conditions of the vegetative propagation of sacha inchi (Plukenetia volubilis L.). The morphobiometric traits of the seed were measured. Different sucrose concentrations during in vitro germination were analyzed. The effects of using indole-butyric acid (AIB) on the adventitious rooting of three types of sacha inchi cutting were also assessed. The percentages of foliar retention, rooted cuttings, cuttings with sprouting and mortality, number of roots per cutting, length of the largest root and dry mass of aerial part and roots were evaluated. Sacha inchi was found to exhibit phanerocotylar epigeal germination, taking from 20 to 25 days. For in vitro cultivation, MS culture medium without the addition of sucrose was used to obtain higher germination rates (70%). The types of cutting used in vegetative propagation produced satisfactory adventitious roots (> 50%), but apical cuttings were more efficient. They were also capable of rooting without the application of AIB, but concentrations of between 0.10 and 0.20 mg L-1 AIB are recommended in the vegetative propagation of this species.