Influence of proline priming on antioxidative potential and ionic distribution and its relationship with salt tolerance of wheat

Abstract

Mechanisms involved in salt tolerance urge exploration and investigation of genotypic variation to assist future breeding programs. Comparative examination of ten wheat cultivars for salt tolerance and their response towards proline-seed-priming was performed. Exposure of wheat seedlings to salinity resulted in prominent reduction in root and shoot growth attributes of all cultivars. Furthermore, decrease in the chlorophyll contents was evident although this varied among cultivars. Wheat seedlings grown from proline pre-treated seeds exhibited improved photosynthetic pigments, besides this response was also cultivar and concentration dependent. Generally, salt stressed plants exhibited higher antioxidant enzyme activities. Proline priming significantly influenced antioxidant activities, however, its magnitude varied. The peroxidase activity varied among wheat cultivars that were evident from the analysis of POD activity on Native-PAGE gel. Salinity caused the accumulation of Na + in the roots and the magnitude of Na + translocation to the shoot was cultivar dependent. Similarly, K + uptake and its distribution among root and shoot varied. Priming treatments affected ion distribution of Na + and K + but inter-cultivar variations were evident. Conclusively, all the cultivars investigated exhibited differential response to salinity and proline seed pre-treatments. However, the proline-priming mediated improvements in growth and antioxidant enzyme activities contributed to stress tolerance which partly relied on the ability of the plant to uptake sodium and its partitioning in the roots. Of the cultivars tested, Faisalabad-08 and Bhakhar-2002 were ranked as relatively salt tolerant and the cvs. AARI-10, MH-97 and Auqab-2000 as relatively salt sensitive.

Seed Pre-treatment with Polyhydroxy Fullerene Nanoparticles Confer Salt Tolerance in Wheat Through Upregulation of H2O2 Neutralizing Enzymes and Phosphorus Uptake

“…Exposure of wheat seedlings to salinity reduced plant growth. In agreement, salinity inhibited plant growth through physio-biochemical disturbances (Hasegawa 2013;Geilfus 2018) and is also reported for wheat plants (Raza et al 2007;Iqbal and Ashraf 2013;Shafiq et al 2018). Wheat plants germinated from PHF-primed seeds exhibited prominent recovery in root and shoot growth under control and salinity.…”

“…Furthermore, a decrease in the carotenoid contents was also recorded for seedlings grown under salinity which caused an increase in the Car Chl −1 relative ratio under salinity stress. Salinity-mediated reduction in the photosynthetic pigments is reported earlier in wheat (Iqbal and Ashraf 2013) and is due to Na + toxicity and oxidative stress (Shu et al 2012;Raza et al 2014;Shafiq et al 2018). The wheat seedlings grown from PHF pre-treated seeds exhibited prominent recovery in the photosynthetic pigments under salinity stress.…”

“…Of limited reports, PHFmediated accumulation of soluble sugars has been reported in Beta vulgaris under water-limited growth conditions (Borišev et al 2016). The retention of compatible osmolytes like soluble sugars, proline, and other free amino acids is linked with better osmotic adjustments under salinity (Flowers and Colmer 2008;Shafiq et al 2018). Other than osmolytes, another important component of osmoregulation is inorganic ions primarily Na + , K + , Ca 2+ , and P.…”

Foliar applied fullerol differentially improves salt tolerance in wheat through ion compartmentalization, osmotic adjustments and regulation of enzymatic antioxidants

“…From an agricultural viewpoint, salinity is a global problem (Tadesse et al 2017;Lagacherie et al 2018) and the accumulation of soluble salts in soils interferes with plant physio-biochemical functioning of glycophytes (Iqbal and Ashraf 2013;Geilfus 2018). In turn, ROS over-production impairs cellular metabolism and hampers crop growth (Feki et al 2017;Shafiq et al 2018). Carefully summarizing this information, the modulation of oxidative stress is a crucial aspect in functional plant biology and could be targeted to induce crop stress tolerance.…”

Protection of Italian ryegrass (Lolium multiflorum L.) seedlings from salinity stress following seed priming with L-methionine and casein hydrolysate

“…However, exogenous application of amino acids such as cysteine, glycine, methionine and serine to the NaCl solution stimulated a higher germination rate. The response of wheat to salinity stress after seed priming with proline was found to be genotype-dependent (Shafiq et al, 2018). In another study, pre-treatment of wheat seeds with 0.01 μM cysteine for 24 h before sowing was found to reduce the negative effects of salinity on early seedling growth (Nasibi et al, 2012).…”