Genetic variation and effective population size of a <i>Myracrodruon urundeuva</i> (Engler) Fr. Allem. provenance and progeny test

<p><i>Ex situ</i> conservation of tree species in provenance and progeny tests allow the estimation of genetic parameters for quantitative traits and are also useful for tree breeding programs. This study aimed at estimating the genetic variability of provenance and progeny test of <i>Myracrodruon urundeuva</i> and providing subsidies for <i>ex situ</i> conservation and the use of germplasm in breeding programs. We also estimated the variance effective population size () of seeds sampled from this test, simulating six different scenarios for test management and seed collection strategies. We estimated genetic parameters for diameter at breast height (DBH), total height, volume and fork in 31-year-old provenance and progeny test established with 91 open-pollinated progenies from five provenances, allocated in a compact family block design at Pederneiras Experimental Station, Sao Paulo, Brazil. The genetic-statistical analysis was based on REML/BLUP procedure. Significant genetic differences were detected only among progenies within provenances. Individual heritability was high for DBH, height, and volume. We hypothesize that inter-tree competition inflated these estimations and have, consequently, overrated the estimates for genetic gain. Thus, this test should be mainly used for conservation purposes. The estimates for varied considering different scenarios, showing that female gametic control is the best strategy to achieve higher gains on , being an important suggestion for the management and seed collection strategies in dioecious species as <i>M. urundeuva.</i>