EFFECT OF PIX (MEPIQUAT CHLORIDE) ON THE SALINITY RESISTANCE OF NEW CULTIVARS OF COTTON (GOSSYPIUM HIRSUTUM L.) IN THE SEEDLING STAGE

In modern agriculture, mepiquat chloride (pix) as a synthetic growth regulator, is considered as an important management tool for reducing stress damage in Cotton seed.In the present study, the effects of the growth regulator, pix were investigated on the physiological and biochemical characteristics in new cultivars of cotton in response to salinity stress in Golestan province, Iran.The experiment was carried out in a completely randomized design enriched with 10 gr.L -1 Pix and 15 ds.m -1 salt (sodium chloride) in Petri dish with three cultivars (Latif, Kashmar and Sahel).The physiological and biochemical parameters of seedlings were measured after 4 days.The use of Pix in saline conditions resulted in a significant increase in germination percentage, radicle length, dry and fresh weights, phenolic compounds, as well as proline and glycine betaine content in the Latif and Kashmar cultivars (p ≤ 0.05).The amount of Na + ion absorption was lower in Kashmar and Latif cultivars compared with the Sahel cultivar while the amount of K + and Ca 2+ ions absorption was increased in the two mentioned cultivars compared to the Sahel cultivar.This study showed that the effects of stress were reduced after treating the seeds with Pix, especially in the Kashmar and Latif cultivars during the seedling stage.