Ali Momenpour; Ali Imani; davod bakhshi; Gholamhasan ranjbar
Abstract
Salinity tolerance threshold of fruit crops is obtained based on the reduction in yield under saline conditions compared to non-saline conditions. In order to determine salinity tolerance threshold and yield reduction per unit increase in soil salinity in selected almond genotypes, a factorial experiment ...
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Salinity tolerance threshold of fruit crops is obtained based on the reduction in yield under saline conditions compared to non-saline conditions. In order to determine salinity tolerance threshold and yield reduction per unit increase in soil salinity in selected almond genotypes, a factorial experiment was carried out. The study was based on completely randomized design (CRD), with two factors: (1) genotypes in 11 types (Tuono, Nonpareil, Mamaei, Shokoufeh, Sahand, Shahrood12, A200,1-25, 1-16 and 13-40 budded on GF677 rootstock, and GF677 rootstock (without budding as control), and (2) salinity of irrigation water at five levels (0.5, 2.5, 4.9, 7.3 and 9.8 dSm-1). At the end of experiment, salinity tolerance threshold and yield reduction slope were calculated based on dry weight (biomass).The results showed that the type and combination of rootstock and scion affect the salinity tolerance threshold and yield reduction slope. The lowest salinity tolerance threshold was observed in 1-16 (2.22 dS/m), Mamaei (2.28 dS/m), and Sahand (2.39 dS/m) genotypes, respectively. On the contrary, the highest salinity tolerance threshold was observed in Shokoufeh (5.80 dS/m), Shahrood12 (4.84 ds/m) and 1-25 (4.80 ds/m).The highest yield reduction slope was observed in 13-40 (8.05%), A200 (7.86%), and Nonpareil (7.55%) genotypes, respectively. In contrast, the lowest yield reduction slope was observed in Shahrood 12 (5.60%). Overall, the results showed the level of salinity that reduced the yield by 50% in Shahrood 12, Shokoufeh, and 1-25, were 5.05, 4.43 and 3.55 dS/m greater than GF677 rootstock (without budding), respectively. EC50 in Shahrood 12, Shokoufeh, 1-25 and GF677 was observed in salinity intensity of 13.23, 12.59, 11.71 and 8.16 dS/m. It should be noted that in previous studies, 100% decrease in yield was reported by salinity level of 7 dS/m, while in Shahrood 12 and Shokoufeh cultivars budded on GF677 rootstock, we observed only 12% and 9% yield reduction by salinity of 7 dS/m. Therefore, we suggest that Shahrood 12 and Shokoufeh cultivars budded on GF677 rootstock could be cultivated in areas with moderate salinity.
Ali Momenpour; ali imani; davod bakhshi
Abstract
Scion-rootstock combination and level of salinity affect on the biochemical characteristics of almond cultivars. To evaluate the effect of salinity stress on the biochemical reactions of almond cultivars and genotypes, a factorial experiment was carried out based on completely randomized design (CRD). ...
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Scion-rootstock combination and level of salinity affect on the biochemical characteristics of almond cultivars. To evaluate the effect of salinity stress on the biochemical reactions of almond cultivars and genotypes, a factorial experiment was carried out based on completely randomized design (CRD). Treatments included two factors: Factor A: genotypes in four levels (‘Shokofeh’,‘Sahand’ cultivars, and ‘13-40’ genotype budded on GF677 rootstock, and GF677 (without budding)), and Factor B: irrigation water salinity in five levels (0.5, 2.5, 4.9, 7.3 and 9.8 dS/m) .Total phenolic, antioxidant capacity, soluble carbohydrate, non-soluble carbohydrate, proline, total soluble proteins, hydrogen peroxide, malondialdehyde, other aldehydes, enzymes activity of catalase, ghayacol peroxidase and ascorbat peroxidase were measured at the end of the experiment. Results showed that, in all genotypes, with increasing salinity level (up to 9.8 dS/m) the content of hydrogen peroxide, malondialdehyde and other aldehydes was increased. Also, the content of total phenolics, antioxidant capacity, soluble carbohydrate, proline, total soluble proteins, enzymes activity of catalase, ghayacol peroxidase and ascorbat peroxidase were higher at the lower salinity levels (2.5 and 4.9 ds/m), but their contents were reduced in higher salinity levels. Overall, the highest content of soluble proteins, enzymes activity of catalase, ghayacol peroxidase and ascorbat peroxidase were recorded at salinity level of 7.3 dS/m, and the highest content of total phenolics, antioxidant capacity, soluble carbohydrate and prolin at salinity level 9.8 dS/m were observed in ‘Shokofeh’ cultivar. Also, at salinity levels of 7.3 and 9.8 dS/m, the lowest content of hydrogen peroxide, malondialdehyde, other aldehydes, and total non-soluble carbohydrate were observed in ‘Shokofeh’ cultivar. Finally, ’Shokofeh’ and ’Sahand’ budded on GF677 rootstock were recognized as the most tolerant and sensitive cultivars to salinity, respectively.