Role of methyl jasmonate on improving salt resistance through some physiological characters in German chamomile (Matricaria chamomilla L.)

To evaluate the effect of spraying with methyl jasmonate on membrance properties, ion uptake and osmotic adjustment and flower dry weight of chamomile (Matricaria chamomilla L.) under salt stress an experiment was conducted at greenhouse with three replications. The experimental design was factorial based on randomized complete blocks design. The studied factors were as follows: spraying with methyl jasmonate at five levels including, 0, 75, 150, 225 and 300 μM in three growth stages: 1) 3 to 4 leaves, 2) stem elongation and 3) flowering (anthesis) and salt stress applied at four levels of 2.1, 6, 10 and 14 dS/m NaCl. The results showed that spraying with methyl jasmonate and salinity stress had significant effects (p ≤ 0.05) on all measured traits. The highest cell membrane stability, proline, K+, Ca+content, ratio of K+/Na+ and flower dry weight, with the lowest content of Na+ were obtained in spraying 75 µM MeJA and 6dS/m salinity stress. High amount of the mentioned parameters at the concentration of 6 dS/m salinity could be related to the assisting role of MeJA through preventing salt entrance and preferential absorption of K+ in mild salinities compared with the control treatment. In addition, application of MeJA induced significant increase in proline content. It seems that increase in proline content leads to cell membrane stability and salt resistance.