Teste de germinação de sementes de alface em diferentes substratos

Abstract

The lettuce (Lactuca sativa) originates from wild species from temperate regions of southern Europe and West Asia. Suitable temperature for lettuce seed germination is around 20ºC, and most cultivars do not germinate at temperatures above 30ºC. The objective of this study was to evaluate the germination percentage and lettuce germination speed index in different substrates. A completely randomized design (DIC) with six treatments and ten repetitions was used, totaling 60 experimental units, and the treatments were: 1) blotting paper (2.02 g), 2) autoclaved sand (500 g), 3) autoclaved light red latosol soil (500 g), 4) vermiculite (500 g), 5) mix of sand with vermiculite (500 g), 6) mix of autoclaved light red latosol with vermiculite (500 g). The treatments were significant (P ≤0.05), and the blotting paper (T1) with 90.8% germination (G), 0.91 germination speed index (IVG) and root weight ( PR) 14.48 g, autoclaved sand (T2) which presented 86% (G), 0.86 (IVG) and 13.81 g (PR), sand with vermiculite (84% G, 0.84 IVG and 13.34 g of PR) and vermiculite (70% of G, 0.7 of IVG and 11.92 g of PR) from lettuce seeds, and the lowest light red latosol autoclaved with vermiculite (30% of G and 0.30 IVG) and autoclaved light red latosol (28% G and 0.28 IVG). It is concluded that the blotting paper presents better germination than the other treatments, however, the substrates sand, vermiculite and the mixture sand and vermiculite have a great potential to be used in the production of lettuce seedlings.