Características comerciais e qualidade de sementes de linhagens avançadas de alface americana

Abstract

The crisphead lettuce has stood out more in the past years in the Brazilian market. Originated in regions of mild climate and low rainfall, this type of lettuce is facing some problems during the production process in Brazil due to the occurrence of diseases, difficulty in forming heads during rainy seasons and the lack of knowledge about yield and quality of seeds. Currently, there is a limited availability of materials in the market that meet those requirements making the development of root-knot nematode resistant cultivars, with good adaptability to different growing conditions and a seed production with significant quantity and quality necessary. This study aims to evaluate 11 families F4:5 crossing “Salinas 88” x “ALF – 008”, selected for resistance to this disease, according to their commercial characteristics and seed yield. An experiment was conducted in randomized complete block designs with three replications and 18 plants per plot. In the commercial state six plants per plot were harvested and their total fresh mass, commercial fresh mass, density and shape of the head were evaluated. Although the families did not differ significantly for total and commercial mass and head density it was possible to select individual plants with superior results for these characteristics. The remaining plants were conducted until the ripening and harvest of the seeds. When the seeds reached their physiological maturity, they were harvested, cleaned, weighed and stored. Germination, first count, speed index germination and emergence tests were performed to check physiologic seed quality and the productivity of each family. The AFX-025C#10-17, AFX-025C#1336-18 and AFX-0225C#136-3 families obtained better results in physiological quality. AFX-025C#175-26 and AFX-025C#189-10 families obtained larger productivity.