Morphological response of German chamomile to heat stress accompanies salicylic acid-mediated under field conditions

ABSTRACT: In order to the study effect of salicylic acid on morphological characters of German chamomile (Matricaria chamomila L. cv Bona) under heat stress conditions. Field experiment was carried out as completely randomized block design with 3 replications. Treatments of this experiment including one German chamomile cultivar (Bona) and five levels of salicylic acid (0, 1, 10, 25 and 100 mg.L-1) were applied. The seeds were sowed in the heat stress sites. Late planting date was set that more growth stages and full flowering period, faced with high temperature. The morphological traits included plant height, capitol diameter, flower wet weight and flower dry weights were assessed. Analysis of variance showed that salicylic acid levels had significant effect on all growth parameters. According to our result, salicylic acid caused increasing heat tolerance of German chamomile under field conditions. At the end of this work, we suggested salicylic acid 100mg.L-1treatment as the best treatment under heat stress in field conditions.