Reproductive biology of the dry forest tree Enterolobium cyclocarpum (Guanacaste) in Costa Rica: A comparison between trees left in pastures and trees in continuous forest

We compared the rate of pollen deposition, the likelihood of fruit producti on, the number of seeds per fruit, the outcrossing rate, and the progeny vi gor of the tropical dry forest tree Enterolobium cyclocarpum for individual s in pastures vs. individuals in continuous forest. We found that flowers f rom trees growing in continuous forests were more likely to have pollen dep osited on their stigmas than flowers from trees in pastures (52.1 vs. 32.3% , respectively). We also found that trees from continuous forests were almo st six times more likely to set fruits and produce more seeds per fruit tha n trees in pastures. Morever, progeny from trees in continuous forests were , on average, more vigorous than the progeny from trees in pastures, as ind icated by 12 of 16 indicators of plant vigor. However, there was no signifi cant difference in the multilocus estimate of the outcrossing rate between the two groups of trees (tm = 1.00 and 0.99 for trees from continuous fores t and trees from pastures, respectively). But there are differences in the correlation of paternity between the progeny of the two groups, where the p rogeny from trees in pastures showed a lower correlation of paternity than progeny of trees from continuous forests (r(p) = 0.104 and r(p) = 0.189, re spectively). We argue that the mechanisms that regulate progeny vigor are d isrupted in trees from pastures. We discuss the implications of these findi ngs for the conservation of E. cyclocarpum.