The effect of some organic acid and plant-derived material treatments on the germination and emergence of lettuce

The research was carried out to investigate the effect of plant materials which are used as an alternative to the synthetic chemicals in organic farming (thyme, mint, basil and garlic oil, hot pepper, and neem tree seed extract) and some organic acids (salicylic and jasmonic acid) on the germination, emergence, and seedling characteristics in lettuce (Lactuca sativa L.) cv Arapsaçı. The seeds of lettuce treated with these materials were subjected to germination and emergence tests at temperature 20 ± 1 °C and 60 ± 5 % RH in autumn period. After that, all seeds (including untreated) were kept at 5 ± 1 °C and again checked for germination, emergence, and seedling characteristics in spring period. Thyme oil affected negatively the germination and emergence, and also, the infected seed ratio increased. Although the infection ratio was 1 % in untreated seeds, it was 7.8 % in the seeds treated with thyme oil. After the storing period, infection ratio of thyme oil was 8.5 % which was higher than other treatments. There was no significant effect of treatments on seedling characteristics. © 2015, Springer Science+Business Media Dordrecht.