کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4566074 | 1628798 | 2016 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Bacillus pumilus alleviates boron toxicity in tomato (Lycopersicum esculentum L.) due to enhanced antioxidant enzymatic activity Bacillus pumilus alleviates boron toxicity in tomato (Lycopersicum esculentum L.) due to enhanced antioxidant enzymatic activity](/preview/png/4566074.png)
• Without inoculation, higher shoot boron (B) accumulation was responsible for tomato shoot growth reduction.
• Bacillus pumilus (PGPR) limited the shoot B accumulation only at moderate level of B supply (B2).
• PGPR conferred tolerance in B-stressed plants through the induced plant antioxidation activity.
High soil boron (B) concentrations in arid and semi-arid regions of the world are responsible for decreased crop productivity. However, the use of plant growth promoting rhizobacteria (PGPR) can improve the plant growth under stress conditions like high B either due to limited uptake of B or enhanced antioxidants production, as PGPR have been shown to enhance the resistance in plants against various abiotic stresses. A pot experiment was conducted under green house conditions according to completely randomized design (CRD) and comprised of four levels of B (0.45, 10, 20, and 50 mg B kg−1 soil) either with or without PGPR. Plants were grown for 10 weeks after onset of experiment and analyzed for mineral composition including B and antioxidation activity. Shoot fresh weight, shoot dry weight and leaf chlorophyll contents were inhibited to increasing levels of B. Interestingly, shoot K+ concentration tended to increase with increasing B levels, particularly at 50 mg B kg−1 soil; third level of B (B3). Similarly, highest shoot B concentrations were observed at high levels of B supply (B3) as compared to all other treatments. Likewise, with the increase in external B supply, antioxidant enzymes activities and proline contents in tomato shoot were enhanced. Bacillus pumilus inoculation significantly improved the shoot fresh weight and dry weight of unstressed (control) as well as B-stressed plants. In general, B. pumilus inoculation enhanced the plant antioxidation activity, particularly superoxide dismutase (SOD) and catalase (CAT) antioxidant enzymes. Contrary, the interaction between high B and B. pumilus remained insignificant for limiting the shoot B uptake except for second level of B (B2) which decreased the shoot B accumulation by 21% as compared to non-inoculated B2. Our results suggest that PGPR inoculation confer tolerance in B-stressed plants through the induced plant antioxidation activity. Additionally, PGPR inoculation reduces the shoot B accumulation, however, differential response of shoot B inhibition is expected to increasing B concentrations.
Journal: Scientia Horticulturae - Volume 200, 8 March 2016, Pages 178–185