Organic seeds storage: A case study with lettuce and salad rocket

Abstract

The objective of this study was to evaluate the germination process of lettuce (Lactuca sativa L.) and salad rocket (Eruca sativa L.) storead cypselae/seeds, both organic and conventional, to verify if one is more suited for seed production. The cypselae/seeds were stored in metal containers in a cold chamber. Then, they were placed inside Gerbox boxes in a Mangelsdorf germinator set at 20 ºC, under continuous fluorescent white light. Germination capacity, time, rate, uniformity, and synchrony were then measured. The experimental design applied to lettuce was completely randomized with 2 varieties x 2 systems (organic, and conventional), with five repetitions of 25 seeds each. The design chosen for the salad rocket followed a similar rationale, with two systems (organic and conventional), comprised of ten repetitions of 25 seeds each. The assumptions were tested, followed by ANOVA, average tests, and charts as functions of time. Lettuce cypselae withstood storage for ten years, maintaining their viability and germination pattern over time. The cypselae in the conventionally-grown Rainha de Maio cultivar were more suitable, while for the Quatro Estações cultivar, the organically-grown ones which were proved to be more suitable. Both conventional and organic salad rocket seeds remained viable for more than nine years. The conventional seeds were faster, more uniform, and presented a greater synchronization index, nevertheless.