Molecular, physiological and morphological analysis of waterlogging tolerance in clonal genotypes of Theobroma cacao L.

摘要: SummaryIn soil, anoxia conditions generated by waterlogging induce changes in genetic, morphological and physiological processes, altering the growth development of plants. Mass propagation cacao (Theobroma L.) plantlets (clones) is affected caused heavy rains irrigation methods used to rooting. An experiment was undertaken assess effects a 45-day flooding (anoxia) on traits 35 elite genotypes, aiming at potentially identifying those with greater tolerance substrate. Eighteen fluorochrome-labeled microsatellite (SSR) primer pairs were genetic variability among clones, 248 alleles being amplified calculate similarity coefficients. The resulting dendrogram indicated presence four major groups, which two represented 60% 31% genotypes tested. A general trend toward high levels heterozygosity also found for traits. survival index (IS) flood observed varied from 30 96%. Clones TSA-654, TSA-656, TSA-792, CA-1.4, CEPEC-2009 PH-17 showed an IS value above 94%, whereas CEPEC-2010, CEPEC-2002, CA-7.1 VB-903 clones mostly waterlogging, below 56%. All displayed lenticel adventitious root formation response although different intensities. To determine whether patterns could be associated anoxia, similarity-grouping analysis performed using ratio between waterlogged control values obtained series variables assessed. No specific pattern responses strictly plantlets. However, results revealed suggest that absence leaf chlorosis may proper trait indicate higher rates under conditions. Consequences these findings are discussed context developing improved strategies mass production genotypes.