Masoud Haghshenas; Mohammad Javad Nazarideljou; Akbar Shokoohian
Abstract
The moderating role of salicylic acid (SA) and putrescine (PUS) as plant growth regulators (PGRs), on the growth parameters and phytochemical and qualitative characteristics of strawberry fruit 'Selva' under osmotic stress was investigated under soilless culture. The osmotic potential (salinity) of the ...
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The moderating role of salicylic acid (SA) and putrescine (PUS) as plant growth regulators (PGRs), on the growth parameters and phytochemical and qualitative characteristics of strawberry fruit 'Selva' under osmotic stress was investigated under soilless culture. The osmotic potential (salinity) of the nutrient solution containing different NaCl concentrations (0, 7.5, 15, 30 and 45 mM) and foliar application of PUS (0 and 1.5 mM) and SA (0 and 1.5 mM) were studied. The results showed a significant decrease in plant leaf area (79.6%), total chlorophyll content (48%), fruit yield (73.5%), leaf relative water content (33%), total protein (33.4%), total phenol (7.8%), and vitamin C content (24.5%) under osmotic stress. Moreover, peroxidase (POD) and superoxide dismutase (SOD) enzymes activity, leaf ion leakage, and soluble carbohydrate and proline content increased significantly under osmotic stress. Application of PGRs had a significant effect on all the studied traits (except for SOD activity). Interactive effects of salinity and PGRs were significant on all the traits except for leaf ion leakage, POD activity, soluble carbohydrates, and protein. The highest total phenol and vitamin C contents were obtained with 15 mM salinity along with foliar application of PGRs. In conclusion, foliar application of PUS and SA ameliorate negative effects of salt stress on growth, yield, and quality of strawberry fruit.
Zahra Heidari; Mohammad Javad Nazarideljou; Younes Rezaie Danesh; Nabi Khezrinejad
Abstract
Water deficit conditions, in addition to reduced water uptake, result in a reduction in nutrient uptake, and consequently, a substantial reduction in growth parameters, yield and quality. Substrate inoculation with arbuscular mycorrhizal fungi (AMF) as an environmentally friendly biofertilizer is an ...
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Water deficit conditions, in addition to reduced water uptake, result in a reduction in nutrient uptake, and consequently, a substantial reduction in growth parameters, yield and quality. Substrate inoculation with arbuscular mycorrhizal fungi (AMF) as an environmentally friendly biofertilizer is an important strategy to improve the growth parameters and quality of products in such conditions. Therefore, an experiment was conducted on zinnia, under different irrigation regimes (40, 70 and 100% of field capacity; FC) and different substrate inoculation levels with Glomus mosseae (0, 2.5 and 5%), in order to examine their possible symbiosis and root colonization on morphophysiological and biochemical parameters in a factorial experiment based on a completely randomized design with three replications. The results showed the positive and significant effects of AMF on morphophysiological traits under all irrigation regimes compared to the control treatment (without AMF) such as flower longevity and antiradical properties. With increased drought stress, root:shoot ratio, flower diameter, flower longevity, water use efficiency (WUE), the chlorophyll content and nutrient uptake were significantly decreased, while the decreasing trends of these parameters were much lower in pots treated with AMF. The lowest cell membrane stability and highest free radicals were observed in 40% FC without AMF. The maximum antiradical and antioxidant properties occurred at the lowest irrigation level with the highest AMF inoculation level. The results indicated a significant increase in flower diameter and longevity, in 70% FC with 5% AMF inoculation treatment compared to the control. Compared with the control, WUE was significantly increased at a 5% AMF inoculation level.
Mohammad Javad Nazarideljou; Masoud Azizi
Abstract
Scape bending disorder is the most important factor affecting postharvest loss of gerbera cut flowers. One of the ultimate reasons for gerbera stem bending is lignin, with deformation structural functions and defensive mechanisms. This postharvest experiment was conducted to evaluate the role of phenylalanine ...
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Scape bending disorder is the most important factor affecting postharvest loss of gerbera cut flowers. One of the ultimate reasons for gerbera stem bending is lignin, with deformation structural functions and defensive mechanisms. This postharvest experiment was conducted to evaluate the role of phenylalanine ammonia lyase (PAL) and peroxidase (POD) enzymes activity in stem bending of two gerbera cultivars; (‘Beaudine’ (sensitive)) and (‘Aqua’(resistant)). This experiment was based on a completely randomized design with three replications over eight days. Results showed the significant effects of cultivar on stem bending percentage, total phenol content, PAL and POD enzyme activities and lignin content (P<0.05). The ‘Aqua’ cultivar had the highest phenol and lignin content and the lowest stem bending percentage. The maximum and the minimum PAL and POD enzyme activities were observed in resistant and sensitive cultivars, respectively. Based on the results, induction of PAL and POD enzymes activity, and consequently lignin formation could have direct effects on stem strength and as a result reduce gerbera stem bending disorder.
Mohammad Javad Nazarideljou; Zahra Heidari
Abstract
The drastic decline of precipitation over the past decade along with overuse of chemical inputs and consequent soil fertility reduction are the most important problems in the approach to agricultural expansion, particularly in urban landscaping. Therefore, an experiment was designed to examine the effects ...
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The drastic decline of precipitation over the past decade along with overuse of chemical inputs and consequent soil fertility reduction are the most important problems in the approach to agricultural expansion, particularly in urban landscaping. Therefore, an experiment was designed to examine the effects of different irrigation levels (40, 70 and 100 % of field capacity, or FC) and different vermicompost (VC) levels (0, 2.5 and 5 %) on the morphophysiological parameters of Zinnia elegance ‘Dreamland Red’ in a factorial experiment based on completely randomized design with three replications. Results indicated a significant reduction in root/shoot ratio, flower diameter, flower longevity, water use efficiency (WUE), photosynthetic pigments and nutrient uptake, along with reduction in the FC, while VC application improved these features. Based on the results, the highest electrolyte leakage and free radicals were observed in the 40 % of FC level without VC treatment, while the highest antiradical property and phenolic compounds were obtained at the same FC level along with 2.5% VC. Moreover, the highest WUE was observed at 2.5% VC with 70% FC, compared to 40% FC with no VC application. The flower diameter and longevity, as the most important indicators of the zinnias’ quality, were significantly affected by the interaction effects of irrigation and organic fertilizers.
