Comparative study on germination and seedling growth of wheat cultivars under salt stress regimes

Abstract

Salinity interferes with germination and hampers the growth of wheat especially at seedling stage which necessitates determining of salt tolerant cultivars. Based upon the current situation a controlled experiment was carried out at the Laboratory of Horticulture, Faculty of Agriculture, Cukurova University, Turkey to comparatively evaluate wheat varieties response to imposed salt stress. Germination and seedling growth properties under salt stress were taken as response variables. The seeds of five bread wheat genotypes ('Wafia', 'Lucilla', 'Envoy', 'Lok1'and 'RSP-561') were placed in Petri dishes with salinity doses (Control (0), 4, 8 and 12 dS.m-1 NaCl) which were applied at germination and subsequent early seedling phases under laboratory conditions. The results revealed that root growth was highly sensitive to salt stress and the varieties of Envoy and Lucilla remained relatively tolerant to salt stress than other cultivars. The biochemical analysis revealed that proline content spiked with increasing salinity level, 'RSP-561' under 8 dS.m-1 and 12 dS.m-1 recorded the maximum proline content. Salt stress boosted leaf proline content of salt sensitive wheat genotypes ('Wafia' and 'Lok1'), whereas declined proline level was observed for salt tolerant cultivars. In addition, salt-sensitive genotypes showed a reduction in chlorophyll content a, b, total chlorophyll and carotenoid while, 'Wafia' and 'RSP-561' recorded the minimum Chlorophylls and Carotenoid contents. Further investigations are needed, however, to enhance understanding of the salt stress effects during the whole growing cycle of wheat.

Determination of The Effect of Salicylic Acid Application on Salinity Stress at Germination Stage of Bread Wheat

“…The increase in salt stress resulted in significant reductions in the root length of both genotypes. In accordance with our findings, many researchers have stated that increasing levels of salinity stress resulted in a higher degree of adverse effects on the root length of many field crops (Yildirim et al, 2015;Iyem et al, 2020;Kizilgeci et al, 2020). Additionally, it was also inferred that SA applications up to 100 mM salinity level imparted a positive effect on the root length of the DZ17-1 genotype.…”

“…The increasing level of salinity caused a proportionate decrease in the dry weight of the seedlings. These results are in complete agreement with those of Iyem et al (2020) who reported that salinity significantly enhanced the dry weight of wheat owing to increased biosynthesis of antioxidants and various enzymes which ameliorated the adverse effects of salinity and ultimately seedling growth was promoted which resulted in the maximized seedling weight of wheat. The effects of SA acid application on seedling dry weight under salt stress conditions were similar.…”

“…Kizilgeci (2021) reported that increasing salt concentrations and decreasing enzyme activities caused a decrease in the coleoptile length of the seeds. Many other researchers have also reported a significant decrease in coleoptile length due to the increase in salt stress (Yildirim et al, 2015;Iyem et al, 2020;Kizilgeci et al, 2020). Responses of genotypes to salicylic acid application under 200 mM salt stress conditions were similar.…”

“…It was observed that the increase in salt stress caused a decrease in the germination rate. Iyem et al (2020) reported that the increase in salt stress negatively affects germination vigour. Furthermore, El Sabagh (2019) reported that salinity stress delays or reduces germination of wheat probably owing to delayed seed imbibition as saline environment hindered the moisture absorption by wheat seeds.…”

“…Salinity is the most adverse factor affecting the quality and productivity of wheat by changing its physiological activities as well as its biochemical activities. Soil salinity adversely affects various morphological structures of wheat including seedling growth, plant height, shoot and root length, root, leaf, fresh and dry weight, root/shoot ratio, and chlorophyll content (Iyem et al, 2020). Salinity stress accelerates all phenological stages of wheat (Grieve et al, 1994), reduces the number of tillering (Abbas et al, 2013), the number of spikelets per spike (Frank et al, 1987), grain weight (Abbas et al, 2013), and negatively affect grain yield (Sorour et al, 2019).…”