Interaction of methyl jasmonate and sodium selenate on certain physiological parameters in Lycopersicon esculentum Mill

Selenium is an essential element in some organisms, but high concentrations can leading to toxicity in plant. Methyl jasmonate hormone plays an important role in defence processes. In this research, the effect of Methyl jasmonate (Me JA) and sodium selenate (Na2SeO4) on growth, content of pigments, phenol, anthocyanin and proline in tomato plants were studied. The seeds to germinate in petri dishes were sterilized. After germination, the seedlings were transferred to pots containing moist sand. The plants with second leaves were treated with of 0, 30 and 60 µM Na2SeO4 and 0, 50 and 100 µM Me JA. After 20 days, plants were harvested and certain assays carried out. The plants were treated with Me JA and Na2SeO4 grew significantly compared with other treatments. In all of treatments chlorophyll a and b contents decreased, however, carotenoid contents in 60 µM Na2SeO4 increased. With addition of MeJA to culture solutions containing sodium selenate, the plants showed increase in amount of phenol and anthocyanin in comparison with plants treated with sodium selenate. MeJA had no significant effect on proline content, but sodium selenate with and without MeJA increased proline content. The results showed that interaction of Me JA and Na2SeO4 reduced the harmful effects of sodium selenate.