Green Fertilization Enhances the Photosynthetic Performance and the Growth of Leguminous Trees for Restoration Plantation in Central Amazon

Abstract

The leguminous tree species Dipteryx odorata (Aubl.) Willd. and Inga edulis Mart. were grown in the field to reforest a degraded area. To investigate the photosynthetic responses and the initial growth of Amazonian forest species under fertilization, the study species were subjected to different treatments: T1 = unfertilized-control, T2 = chemical fertilization, T3 = green fertilization and T4 = green and chemical fertilization. D. odorata showed the highest absolute growth rates in height under treatments T4 (10.2 cm&middotmonth-1) and T2 (12.2 cm&middotmonth-1). I. edulis exhibited the best performance for this same parameter in T4 (23.0 cm&middotmonth-1). The highest photosynthesis values (Pn) for both D. odorata (13.1 μmol&middotm-2&middots-1) and I. edulis (20.6 μmol&middotm-2&middots-1) were found in T4. The two species also showed the highest performance index values (PIABS) under T4 (D. odorata = 2.9 and I. edulis = 5.2). Our results suggest that the combination of green and chemical fertilization was the most effective of the four treatments evaluated for improving the photosynthetic performance and the growth of both species during the initial establishment of the species in a degraded area.