Growth of Parapiptadenia rigida inoculated with rhizobia and arbuscular mycorrhizal fungi in the nursery and field

Abstract

Parapiptadenia rigida is a N-fixing arboreal legume native to the Atlantic Forest of southern Brazil. It is commonly used in urban afforestation, restoring riparian forests and agroforestry systems (AFSs). In this study, an experiment was conducted with nine treatments with the objective of evaluating the growth of Parapiptadenia rigida seedlings inoculated with rhizobia and arbuscular mycorrhizal fungi (AMF) under nursery conditions and in the field, with the seedlings being inoculated with: (a) BR 9004 strain (Paraburkholderia sp); (b) BR 3804 strain (Mesorhizobium plurifarium); (c) BR 827 strain (Ensifer fredii); (d) BR 9004 strain+AMF; (e) BR 3804 strain+AMF; (f) BR 827 strain+AMF; (g) Mycorrhizal control (AMF inoculation only); (h) Nitrogen control (with nitrogen fertilization only); (i) Absolute control (without inoculation and without fertilization). The seedlings were evaluated for height and root collar circumference (SC) after 120 days in the nursery, and then for root, shoot and nodule dry mass, mycorrhizal colonization, counting and identification of spores in the substrate after 150 days in the nursery. The seedlings were transplanted into the field at 330 days and monitored in relation to height growth, SC and survival up to 420 days after planting. The BR3804+AMF and BR9004+AMF treatments stood out in growth and survival, respectively, and were related to the occurrence of Glomus sinuosum and Acaulospora scrobiculata spores in the rhizosphere of seedlings.