Shamsul HAYAT, Barket ALI, Syed Aiman HASAN, Aqil AHMAD

Effect of 28-Homobrassinolide on Salinity-Induced Changes in Brassica juncea

Seedlings of Brassica juncea Czern & Coss cv. Varuna generated from seeds soaked in 0, 50, 100, or 150 mM NaCl for 6 h were treated with 0, 10-10, 10-8, or 10-6 M 28-homobrassinolide (HBL) after 14 days of growth. Plants that received only NaCl treatment exhibited a decrease in nitrate reductase and carbonic anhydrase activity, chlorophyll content, and PN 60 days after sowing (DAS), and decreased seed yield at harvest (140 DAS). Subsequent treatment with HBL significantly increased all of the above parameters. The 10-8 M concentration of HBL generated the best response and also overcame the detrimental effects of NaCl more effectively when NaCl treatment was at the 50 mM level. Tissue proline concentration exhibited a different pattern, increasing in response to both NaCl and HBL treatment; 10-8 M of HBL interacted with 150 mM NaCl most significantly and increased the concentration of proline more than all other treatments. The study results suggest that HBL can be considered an important plant protector under NaCl stress conditions. Abbreviations: CA: carbonic anhydrase; DAS: days after sowing; HBL: 28-homobrassinolide; NR: nitrate reductase; PN: photosynthetic rate

Anahtar Kelimeler:

Carbonic anhydrase, chlorophyll, nitrate reductase, photosynthesis, seed yield

Effect of 28-Homobrassinolide on Salinity-Induced Changes in Brassica juncea

Keywords:

Carbonic anhydrase, chlorophyll, nitrate reductase, photosynthesis, seed yield,

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