Survival of Swietenia mahagoni in the xerophytic corridor of the Guantánamo valley

Abstract

The survival of Swietenia mahagoni obtained in nursery with the application of arbuscular mycorrhizal fungi (AMF) and different organic substrates was evaluated. Plants produced on two levels of substrates: cocoa husk, coconut fiber and composted pine sawdust in 6:2:2 and 2:6:2 ratios, and four levels of mycorrhizal strains: Glomus cubense, Rhizoglomus irregulare, Funneliformis mosseae and non-mycorrhizal, were used for a total of eight treatments. Plants in the field were distributed under a randomized block experimental design, with four replications per treatment; the planting frame used was 2 x 2 m. The plantation was done after 30 days and the survival was assessed monthly until 12 months. During this time, the morphological variables: height and diameter were registered, and the height to diameter ratio and the relative growth rate were calculated. Survival analysis was performed using the Kaplan-Meier estimator and proportional hazards regression was performed to determine the risk of mortality as a function of morphological variables. At 12 months after planting, an average survival rate of 86.30 % was obtained, with higher percentage for plants inoculated with Glomus cubense and Rhizoglomus irregularestrains in the substrate composed of 20 % cocoa husk + 60 % coconut fiber + 20 % sawdust. Diameter was the morphological variable most related to the risk of mortality in the planting sites