Comparación del crecimiento de Argopecten purpuratus entre cohortes obtenidas de captación de larvas en ambiente natural y de hatchery/Comparison of growth among cohorts obtained Argopecten purpuratus larval recruitment in natural and hatchery

In Chile crops of the northern scallop Argopecten purpuratus have been developed intensively from seeds obtained in natural environment, and since 1980 from hatchery's seed, when this technique could be controlled and developed. In order to provide information on the performance of seeds of northern scallops in this study growth in length between cohorts produced from seeds obtained in natural environment (CN) and hatchery (CH) in Tongoy (Chile) was compared using ANCOVA. We assessed the consistency of this comparison in different years and seasons. The compared cohorts are pairs of cohorts produced simultaneously in the years 2003 (spring), 2005 (winter) and 2006 (summer). Statistical analysis showed that there are significant statistical differences between cohorts obtained from natural environment and those obtained in hatchery. The Tukey's test showed differences between CN^sub 2003^ and CH^sub 2003^ and also between CN^sub 2005^ and CH^sub 2005^, while there were no significant differences between CN^sub 2006^ and CH^sub 2006^. These differences indicate that the cohorts of natural environment seeds grew faster than those of hatchery. Inter annual comparison showed significant statistical differences. These results are discussed in terms of the cultivation temperature and the heterozygosity for the growing population. [PUBLICATION ABSTRACT]