Seleção massal estratificada como estratégia de melhoramento em coentro para tolerância à salinidade e à acidez da solução nutritiva

Abstract

As an olive grower widely appreciated in the North and Northeast of Brazil, coriander is grown in environments subject to salinization and acidification. In this context, the development of cultivars tolerant to these abiotic stresses is necessary. This work aims to obtain populations of Coriander Verdão tolerant to salinity and acidity, using stratified mass selection as an improvement method. One polycross was carried out between plants from 5 seed producing companies to obtain the base population and 4 cycles under saline stress with electrical conductivity 8.0 dS.m1 and 3 cycles under acid stress with pH 4.0. The characteristics evaluated were height and number of leaves at 14, 21, 28 and 35 days after planting and fresh mass of the aerial part, dry mass of the aerial part, fresh mass of the roots, dry mass of the roots, length of the roots, rate of accumulated growth and succulence of the aerial part at 35 days after planting, at the time of harvest. All cultivations were carried out in a greenhouse, in hydroponics with substrate. For the salinity experiment, significant differences were found for the source of variation, planting time and salinity, but there was no significant difference for source populations and for interactions between sources. For the acidity experiment it was found that there was a significant difference for planting time and between few characteristics for populations. There were also no significant differences for the interactions between the sources. The absence of interactions shows that the factors are independent, and the improvement can be practiced at any time of planting. Although there was no effective result for the selection, important information was found, such as the possibility of growing Verdão coriander in a nutrient solution with an electrical conductivity of 8.0 dS.m-1 with reduced production and at a satisfactory pH 4.0. It was also identified that the cultivation of Coriander Verdão in a greenhouse under saline stress and acidity is affected by environmental conditions.