Somaye Amraee Tabar; Ahmad Ershadi; Tahmine Robati
Abstract
This study was performed to investigate the effect of Putrescine and Spermine on some physiological and biochemical characteristics and antioxidant enzymes activity of peach (Prunus persica cv. Alberta) and almond (Prunus dulcis cv. Rabi) seedlings under water deficit. The first factor was water regime ...
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This study was performed to investigate the effect of Putrescine and Spermine on some physiological and biochemical characteristics and antioxidant enzymes activity of peach (Prunus persica cv. Alberta) and almond (Prunus dulcis cv. Rabi) seedlings under water deficit. The first factor was water regime at two levels (80% or 50% of soil available water), and the second factor was polyamine treatments (putrescine 0.1, putrescine 1, spermine 0.1, spermine 1 mM and control). Water deficit led to increased electrolyte leakage percentage in peach leaves, compared to almond. Under water deficit, polyamines reduced electrolyte leakage in both plants, Spermine was more effective than Putrescine under water deficit. Leaf contents of soluble carbohydrates, proline and soluble proteins in almond more increased as compared to peach. Spermine more effectively increased concentration of osmoregulants, compared to Putrescine. Under water deficit, the activities of catalase, guaiacol peroxidase and ascorbate peroxidase enzymes increased in both plants, higher enzyme activity was found in almond leaves in comparison with peach. The maximum antioxidant enzyme activity was found following spermine treatments. Application of spermine and putrescine increased drought tolerance in almond and peach through reducing the electrolyte leakage, increasing compatibility osmolytes and antioxidant enzyme activity.
Najmeh Jami; Seyed Mohsen Mousavi Nik; Mahdi Naghizadeh
Abstract
To study the effects of drought stress and foliar application with salicylic acid on yield andit’s components and percentage of essential oil of Nigella sativa L., a field experiment was conducted as split plot based on randomized complete block design with three replications at research farm of ...
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To study the effects of drought stress and foliar application with salicylic acid on yield andit’s components and percentage of essential oil of Nigella sativa L., a field experiment was conducted as split plot based on randomized complete block design with three replications at research farm of Shahid Bahonar University of Kerman during growing season of 2013- 2014. The main factor was drought that included in three levels: no tension (90 percent field capacity), moderate tension (70 percent field capacity) and severe tension (50 percent field capacity). The other factor included four concentrations of salicylic acid: zero (foliar application with distilled water), 5, 10 and 15 Micro molar salicylic acid for foliar application. The results showed that there were significant differences between traits including: the number of grains per plant, 1000 seeds weight, harvest index, essential oil and grain yield with applying drought and salicylic acid. The foliar application with salicylic acid (10 Mm) caused increasing 79.05 percent on the grain yield. The interaction of salicylic acid and drought stress on the number of grains in folicules, the percentage of essential oil and biological yield was significant. The interaction of third level of salicylic acid and moderate drought stress caused increasing 150 percent in essential oil. Therefore to obtain the maximum biological yield, the number of grains in folicules and essential oil percentage on drought condition, we can apply third level of SA (S3 = 10 Mm) and moderate irrigation in black cumin that is economic in arid places.
Kamran Amiri Nasab; Hedayat Zakizadeh; Mahmoud Ghasemnezhad; Hassan Biglouei
Abstract
Drought preconditioning (DP) is a method of irrigation with low frequency and longer duration, to extend the root system and suppress drought damage in plants. In the present study, the effect of DP for 30 days on increasing tolerance to drought stress in two turfgrass species, creeping bentgrass (Agrostis ...
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Drought preconditioning (DP) is a method of irrigation with low frequency and longer duration, to extend the root system and suppress drought damage in plants. In the present study, the effect of DP for 30 days on increasing tolerance to drought stress in two turfgrass species, creeping bentgrass (Agrostis stolonifera cv.Palustris) and tall fescue (Festuca arundinacea cv. Greystone) was investigated. DP and control plants were irrigated for 50 days with different levels of soil suction (20-23,40-43, 50-53 and 70-73 centibar), and finally, plants were watered up to field capacity point for 15 days, to recover from stress. Results showed that DP significantly lead to reduction in shoot length and increase in root length in both turfgrass species. DP plants showed less shoot dry and fresh weight and also less electrolyte leakage (EL) at each levels of stress, in compare with the control. Furthermore, DP plants showed greater reduction in EL after recovery. DP treatment also reduced leaf RWC at the end of 50 days of stress and after recovery in tall fescue, but in creeping bentgrass retained it at the control level. Overall, it appears that DP treatment can increase tolerance to drought stress in two species with increasing root length, reducing shoot length and EL and preserving leaf RWC.