Genetic progress of selections between and within caribbean cherry open pollination progenies
João Rodrigues de Paiva; Ricardo Elesbão Alves; Francisco Ivaldo Oliveira Melo; Everton Rabelo Cordeiro and Adriano da Silva Almeida
The objective of this study was to estimate the genetic parameters of Caribbean cherry tree populations and select the most favorable individual plants by using the between-and-within a progeny selection method, as well as the index selection method which simultaneously takes into account the performance of each progeny for all the assessed traits. The experiment was carried out in April 1996 in a randomized complete block design with 62 treatments (open pollination progenies) and three replications at the Experimental Station at the Embrapa Tropical Agroindustry, in Pacajus, CE. Single row plots of four plants were used, and the spacing was 4 m between rows and 3 m between plants within rows. The progenies were assessed for fruit yield and physicalchemical traits of fruits according to vitamin C content, total soluble solids content (ºBrix) and mean fruit weight (PMF). The estimated monthly yield gains (in percentage) from selection between and within progenies varied from 3.68% to 44.98% respectively, in the June and May 1999 assessments. The variation for the other traits was from 28.3% to 327.2% respectively, for total titer acidity and pH. Plants in the next cycle population are expected to present a vitamin C content higher than 30% compared to those from the first selection cycle. The use of a selection index that simultaneously considered the classification of each progeny for the assessed traits screened progenies showed a coincidence of 84% progenies in relation to those selected using the between and within progeny selection method. This suggested that the index method was efficient compared to the traditional method.