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Grafting on a moderate salt-tolerant rootstock (Vista-306) and bacteria (Serratia marcescens) inoculation were tested whether grafting and bacteria can alleviate salinity stress in eggplant. Two salt-tolerant eggplant genotypes ('Mardin Kızıltepe', 'Burdur Merkez') and two salt-sensitive eggplant genotypes ('Artvin Hopa', 'Kemer') were used as scions. Grafted and non-grafted seedlings with 4–5 true leaves were transferred to pots filled with a mixture of peat: perlite (2:1) in a controlled greenhouse and were cultivated under temperatures of 23–25 °C with approximately 50–55% relative humidity. After 10 days from planting, 20 mL bacteria solution (cell density of 3 × 108 cells mL−1) per plant was applied to the root region of the seedlings as inoculum. 200 mM NaCl solution was applied to plants for 20 days after 5 days from inoculation of the bacteria. The study was arranged in a randomized block factorial design with three replicates. The grafted seedlings induced salt tolerance registering lower foliar concentrations of Na+ and Cl–, the lower lipid peroxidation and higher antioxidative enzyme activities. Inoculation of the bacteria significantly counteracted the salt-induced adverse effects on growth characteristics, leaf Cl−, Na+ contents, and antioxidative enzyme activities. In conclusion, grafting and inoculation with Serratia marcescens are effective in improving growth and some key physiological processes in eggplant under salt stress. [ABSTRACT FROM AUTHOR]

The seedlings of 3 green bean genotypes ('Balk'z', 'Ferasetsiz', 'Local Genotype') were grown for 4 weeks at 30/15°C (day/night) temperature with 65% humidity and then transferred to a growth chamber. The temperature in the growth chamber was increased stepwise to 35, 40, 45 and 50°C to create a heat-stressed environment. In addition, to determine HST (LT50), the leaf discs of each genotype were exposed to 35, 40, 45, 50, 55 and 60°C. According to results, 'Ferasetsiz' and 'Local Genotype' had the highest leaf relative water content (RWC), while the 'Balkız' had the lowest. However, 'Ferasetsiz' and 'Local Genotype' had the lowest loss of turgidity and malondialdehyde (MDA), while 'Balkız' had the highest. The leaf area and chlorophyll content (Chl) were not associated with the HST of genotypes. Many protein bands, in mass range 27-157 kDa, were detected depending on the genotypes and heat treatments. Besides, a few new proteins appeared in response to heat stress. Based on the data collected, 'Ferasetsiz' and 'Local Genotype' were determined to heat tolerant genotypes, while 'Balkız' was relatively heat sensitive genotype. [ABSTRACT FROM AUTHOR]

In this study, apoplastic antioxidant enzymes in the leaves of two strawberry cultivars ('Aromas' and 'Diamante') and their relationship to cold-hardiness were investigated. Fully expanded, uniformly sized leaves from 1-year-old field plants of the cultivars were collected at the hardening (late autumn, in November and winter, in January) and de-hardening (summer, in July) stages. Leaf samples were exposed to low temperatures of 5, -5, -10, -20 and -30°C for 12 h to determine their cold-hardiness (LT50; lethal temperature, where 50% of the plants were killed). Cold-acclimation produced a remarkable increase in cold-hardiness. It was found that 'Diamante' had higher cold-hardiness than 'Aromas'. Moreover, malondialdehyde and total carotenoid content increased during the hardening stage and decreased during the de-hardening stage. The activities of catalase, peroxidase and ascorbate peroxidase in the leaf apoplast and nicotinamide adenine dinucleotide phosphate oxidase activity in the leaf tissue were correlated with changes in cold-hardiness. The activities of these enzymes were higher in the hardening stage than in the de-hardening stage. The activities of apoplastic catalase, peroxidase and ascorbate peroxidase varied significantly depending on the cold-acclimation stage and the cold-hardiness level of the cultivars. This study indicates that elevated apoplastic antioxidative enzymes may be determinants of cold-hardiness in the strawberry plant. The lower malondialdehyde content and higher total carotenoid and apoplastic enzyme activities in 'Diamante' indicated an enhanced cold-hardiness capacity of this cultivar, serving to protect the plant from oxidative damage. [ABSTRACT FROM AUTHOR]

Seedlings of two strawberry cultivars 'Camarosa' and 'Chandler' were grown using perlite in a greenhouse for 20 days, and then plants were watered with nutrient solution containing 0, 8.5, 17.0, and 34.0 mM sodium chloride (NaCl) for 6 months. Sodium chloride treatments generally reduced the leaf and root dry weight. Relative water content (RWC) of leaves was maintained despite the increased salt concentrations while loss of turgidity was increased by sodium chloride (NaCl) treatments in both cultivars. As the most variable amino acids, aspartic acid, glutamic acid, arginine, proline, serine, and alanine were determined under salt stress in plants. Sodium chloride treatments generally increased sodium (Na) and chloride (Cl) contents in all plant parts. The plants were able to maintain high potassium (K) levels in the aerial parts with the 8.5 mM NaCl treatment. It can be concluded that 'Camarosa' has the ability to osmotic regulation. 'Chandler' also tolerates the salt injury at low salt concentrations. [ABSTRACT FROM AUTHOR]

The effects of salt (NaCl) applications of various concentrations (0, 500, 1000 and 2000 mg/L) for 6 months on 'Camarosa' and 'Chandler' strawberry varieties grown in perlite and perlite:zeolite (1:1) media were investigated. In order to determine the salt resistance of varieties, the tolerance index (T.I.) and tolerance ratio (T.R.) were calculated on the basis of total chlorophyll content, and leaf and root dry weight. Also, the ability of keep in balance for potassium:sodium (K:Na) ratio in the aerial part and roots of plants were considered. It was determined that the highest T.I. and T.R. values calculated on the basis of leaf and root dry weight in cv. Camarosa in both media. Concerning the evaluations calculated on the basis of total chlorophyll, the results indicated that 'Chandler' is more resistant in perlite medium, 'Camarosa' is more resistant in perlite:zeolite (1:1) medium. K:Na ratio decreased with increasing salinity in both varieties. However, it was determined that K:Na ratio is higher in cv. Chandler, i.e., 0.83 than in cv. Camarosa (0.61). As a conclusion, it was determined that 'Camarosa' was more resistant to salt than 'Chandler'. In addition, regarding the salt resistant performance of plants, perlite:zeolite (1:1) medium had more effective results than perlite. [ABSTRACT FROM AUTHOR]

Sodium chloride (NaCl) treatments were conducted on strawberry plants (Fragaria x ananassa cvs. Camarosa and Chandler) grown under greenhouse conditions. Modified Hoagland solution (one-third strength) containing 0 (control), 8.5, 17.0 and 34.0 mM NaCl was applied to the plants for 6 months. High NaCl concentrations caused serious reductions in growth parameters such as fresh weight (FW) of leaves, stems and roots, leaf area and the number of leaves. Addition of salt to the growth medium caused a reduction in stomatal conductance (Gs) and transpiration rate (E) of Camarosa. Saline water up to 34 mM NaCl did not have any influence on Gs of Chandler. In addition, 34 mM NaCl treatment caused a marked increase in Gs and E of Chandler. On the other hand, leaf temperature (T1) increased with salt treatments in both cultivars. We suggest that the reductions in stomatal conductance and transpiration rate represent adaptive mechanisms to cope with excessive salt in Camarosa. As it can relatively maintain its stomatal conductance and transpiration rate, Chandler also tolerates the salt injury at low salt concentrations. Considering the cultivars, Camarosa was characterised as more salt tolerant than Chandler under saline conditions. [ABSTRACT FROM AUTHOR]

Various concentrations of NaCl (0, 500, 1000, and 2000 mg/L) were applied to plants of the “Camarosa” and “Tioga” strawberry varieties for 10 weeks. At the end of the experiment, it was determined that the leaf dry weight increased especially at 500 and 1000 mg/L NaCl treatments when compared to control treatment. However, salt applications did not change total chlorophyll content. With the salt applications, iron (Fe) and manganese (Mn) content increased, while copper (Cu) content did not change in the aerial part of plants in both varieties. On the other hand, zinc (Zn) content increased in the “Tioga” strawberry variety. In the root part of plants, Fe, Zn, Mn and contents did not change according to salt applications in both strawberry varieties. However, 2000 mg/L NaCl of salt applications increased Cu content in the “Camarosa” strawberry variety significantly. [ABSTRACT FROM AUTHOR]

The effects of salt (NaCl) applications of various concentrations (0, 500, 1000, and 2000 mg/L) for 10 weeks (69 days) on the morphologic properties and ionic composition of the "Camarosa" straw- berry variety grown in perlite and perlite : zeolite (1:1) media were investigated. Injuries of varying severity appeared in the plants depending on the increase of NaCI concentration. At the end of the salt applications, in the aerial part of the plants, the amounts of sodium (Na), chlorine (Cl), calcium (Ca), and magnesium (Mg) had generally increased, while the amount of potassium (K) and phosphorus (P) had decreased. in the roots of the plants, salt applications increased the amount of Na and Cl and decreased the amount of K and Mg; however, they did not change the amount of Ca and P. In addition, in the aerial parts of the plant, the amounts of Ca and Mg were higher in the perlite : zeolite (1:1) medium than in the perlite medium generally. It was observed that in the roots, the amount of K was higher in the perlite medium, whereas the amount of Mg was higher in the perlite: zeolite (1:1) medium. It was determined that 500, 1000, and 2000 mg/L NaCI levels caused osmotic effects in the "Camarosa" strawberry variety. Moreover, they possess the ability to bring about osmotic regulation. [ABSTRACT FROM AUTHOR]

Potassium (K) is present in higher concentrations than other macronutrients in cherry fruits and is most often associated with changes in fruit quality. This study was carried out in the Sultandağı district of Afyon province between 2015 and 2017 in the cultivation "ziraat 900" sweet cherry cultivar grafted Prunus padus rootstock on aged 15–20 years. The effects of soil K applications (as potassium sulfate (K2SO4) on sweet cherry quality and mineral content were investigated. Different concentrations of K2SO4 (0, 500, 1000, and 1500 g trees−1) were applied under the canopy at one time before full bloom. After harvested fruit length, fruit weight, flesh firmness, water-soluble dry matter (WDM), and mineral content [Calcium (Ca), Magnesium (Mg), Potassium (K), Phosphorus (P), Iron (Fe), Copper (Cu), Zinc (Zn), Manganese (Mn)] were determined. Fruit quality criteria (fruit length, weight, flesh firmness, and WDM content), fruit K and Cu contents values increased depending on the application of K. It was observed that fruit length increased by 9%, fruit weight by 23%, flesh firmness by 24% and WDM content by 20% due to K applications. Potassium application decreased the content of Ca and Mg. This study indicates that the application of K caused an increase in the fruit quality of the sweet cherry. [ABSTRACT FROM AUTHOR]

The effects of salinity and zinc (Zn) priming on the physical and mineral composition of green bean genotypes were investigated on two green bean genotypes ('Şeker Fasulye' and 'Local Genotype') by soaking seeds in 0.05% Zn (ZnSO4.7H2O) solution and by exposing to salt stress by applying 50, 100 and 150 mM NaCl after first true leaf emergence. Plants not exposed to salt stress were treated as control. The effects of Zn priming on the salt tolerance of genotypes, fresh and dry weight of plant leaf relative water content (RWC), loss of turgidity (LOT), Na, K, Ca and Zn concentrations in the leaves, stem and root portions of plants were evaluated. The NaCl concentrations led to significant variations in the examined parameters. The highest concentration of salt (150 mM) caused fading in leaves and led to inhibition of growth and development. Salt application generally reduced the fresh and dry weights of plants of both genotypes where Zn priming showed an amendatory effect. Leaf RWC decreased with salt applications while LOT increased but Zn priming had no amendatory effect on these parameters. 'Şeker Fasulye' genotype was found to be relatively more salt tolerant than 'Local Genotype' on the basis of the investigated parameters. Zinc priming decreased the Na and Ca concentrations in plant organs; however, a decrease in K concentration was observed due to increase in NaCl. [ABSTRACT FROM AUTHOR]

The mechanism of tolerance to high temperatures was investigated in two strawberry (Fragaria × ananassa Duch) cultivars, 'Redlands Hope' ('R. Hope', heat tolerant) and 'Cal. Giant 3' ('CG3', heat sensitive). Leaves were collected from plants that were exposed to gradual heat stress and heat-shock stress separately. The contents of nonenzymatic antioxidants such as ascorbic acid (AsA) and glutathione (GSH) and the activities of enzymatic antioxidants such as ascorbate peroxidase (APX) (EC 1.11.1.11), catalase (CAT) (EC 1.11.1.6), and glutathione reductase (GR) (EC. 1.6.4.2) were measured followed by heat treatments. Additionally, proline content was determined, and heat shock proteins (HSPs) were analyzed with an immunoblotting method to investigate protein markers involved in the heat-stress tolerance of strawberry plants. The contents of AsA and GSH did not change depending on heat stress type, temperatures, or cultivars. While APX and CAT activities increased with high temperatures, GR activity was almost unchanged. The proline content of the cultivars increased in both treatments. Anti-HSP60 immunoblots revealed that a 23 kDa polypeptide was detected during the heat acclimation of strawberry cultivars. The intensity of the heat shock protein in 'R. Hope' plants was more than in 'CG3' plants. Thus, the accumulation of 23 kDa heat shock protein was correlated with the heat tolerance of the cultivars. In conclusion, strawberry leaf tissues of 'R. Hope' were found to enhance the structural stability of cellular membranes under high temperature by increasing both the activity of such enzymes as CAT and APX to activate the antioxidative systems and the expression of 23 kDa HSP. [ABSTRACT FROM AUTHOR]

Physiological parameters were used to investigate genotypic variations in 15 strawberry cultivars ['Aromas', 'Camarosa', 'Carmine', 'Cal. Giant 3' (CG3), 'Cal. Giant 5' (CG5), 'Elsanta', 'Fern', 'Festival', 'Honeoye', 'Kabarla', 'Redlands Hope' (R.Hope), 'Ruby Gem', 'Selva', 'Sweet Charlie' and 'Whitney'] and their relationship to heat-stress tolerance (HST). Cold stored (frigo) strawberry seedlings were grown in pots for six weeks and then transferred to a growth chamber. The temperature in the growth chamber was increased stepwise from 35 to 40,45 and 50°C to create a heat-stressed environment. Leaf relative water content (RWC), loss of turgidity and chlorophyll content were measured at each temperature. The 'Elsanta' and R.Hope' had the highest RWC, while the 'Festival' and 'CG3' had the lowest. However, 'Elsanta' and 'R.Hope' had the lowest loss of turgidity, while 'Festival' and 'CG3' had the highest. 'Elsanta' and 'R.Hope' showed the lowest chlorophyll content, and 'CG3' and 'Whitney' had the highest. To determine HST (LT50), leaf discs of each cultivar were exposed to 35,40,45, 50,55 and 60°C. A considerable decrease in the LT50 was observed with increasing temperature in all cultivars. The LT.0of the cultivars ranged from 51.8 to 52.9°C. Based on the data collected, 'Elsanta', 'R. Hope' and 'Camarosa' were determined to be relatively heat-tolerant cultivars, while 'Whitney', 'Fern', 'Festival' and 'CG3' were heat-sensitive cultivars. [ABSTRACT FROM AUTHOR]

Abstract: The response of melon (Cucumis melo) plants to long-term salinity was investigated to determine the availability of the NaCl pre-treatments (seed priming+seedling conditioning) as an interesting strategy for increasing the salt tolerance. Seeds of melon cultivars “Hasanbey” and “Kirkagac” were primed with 18dSm−1 NaCl solution for 3 days at 20°C. During emergence and seedling growth, non-primed seeds were irrigated with local irrigation water (EC: 0.3dSm−1) whereas primed groups were treated with 9.0dSm−1 saline solution for 35 days. Seedlings derived from pre-treated (P) and non-pre-treated (NP) groups were transplanted to 8l pots. After transplanting, salinity treatments were started with the first irrigation. The salinity treatments consisted of five levels (control, 4.5, 9.0, 13.5 and 18.0dSm−1) of irrigation solution for a period of 90 days. NaCl pre-treatments diminished the inhibiting effect of salinity on growth of melon plants. However, competence for salt adaptation varied with cultivar and the level of salinity. The physiological response of the P plants was also maintained in the long-term. Stomatal conductance and relative chlorophyll content of P plants tended to be higher than those of the NP ones. In addition, NaCl pre-treatments enhanced K and Ca concentrations of leaves and stems, and prevented toxic effects of salinity because less Na accumulated in stems. These results suggest that the use of NaCl pre-treatments could be a useful strategy to increase the salt tolerance of melon plants in the long-term and also to permit the establishment of melon crop by direct sowing in a saline medium. [Copyright &y& Elsevier]

We investigated the possibility that oxidative stress contributes to blossom-end rot (BER) initiation in bell pepper (Capsicum annuumL.) grown under high salinity. Pepper plants (cv. Mazurka, Rijk Zwaan, the Netherlands) were grown in a greenhouse and irrigated with nutrient solution made up with either desalinated water (control— rising from E.C. 1.9 to 2.4 dS m−1) or saline water (salinity– rising from E.C. 3.2 to 7.0 dS m−1). Irrigation was by a circulation system. BER symptoms were observed throughout the experiment but were highly enhanced in the salinity–grown plants during the spring and summer. The fruit calcium concentration was not affected by salinity, but manganese concentrations in both leaves and fruits were significantly reduced under these conditions. Under salinity there was an enhancement of apoplast reactive oxygen species (ROS) production, which was partly a result of increase in NAD(P)H oxidase activity in the pericarp of pepper fruit at the stage that it was most sensitive to BER. Apoplast ROS production and extracted NAD(P)H oxidase activity were inhibited by manganese, zinc and to a lesser extent by calcium. These cations also negated the enhancement of ROS production caused by incubation of fruit pericarp discs in NaCl solutions. Manganese, zinc and calcium also inhibited NAD(P)H oxidase activity, extracted following their infiltration into fruit pericarp discs. The results suggest that generation and scavenging of oxygen free radicals in the apoplast may contribute to the appearance of BER symptoms in pepper fruits under saline conditions. It is suggested that manganese may serve as antioxidant in pepper fruit and that manganese addition to peppers grown under salinity may alleviate BER symptoms in the fruits. [ABSTRACT FROM AUTHOR]