Low-cost tools for large-scale seed scarification: efficiency in two species from South American arid lands

Abstract

The use of native plants for arid land restoration requires the application of pre-germination treatments to alleviate seed dormancy mechanisms. As it is known, scarification allows several valuable species to overcome the primary forms of dormancy. However, supplying large quantities of scarified seeds at a low cost represents a significant challenge. In this context, our objective was to evaluate locally constructed machines accessible to people of degraded lands in a state of poverty. The effectiveness was evaluated by comparing two native shrubs from South American arid lands, Larrea divaricata and L. cuneifolia. Four treatments were applied: control (T0), mechanical scarification with a hand drill equipped with sandpaper on its head (T1), and mechanical scarification for 15 seconds (T2) and 30 seconds (T3) with a self-constructed machine, capable of regulating pressure and speed. For both species, the germination probability was higher with T2 (0.82 AE 0.02) compared to T0 (0.28 AE 0.03) and T1 (0.65 AE 0.03). T3 presented intermediate values (0.75 AE 0.03) but did not differ significantly from T1 and T2. Our results show the effectiveness of a locally constructed seed scarification tool to upscale seed-based restoration in arid lands.