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To investigate the influence of jasmonic acid (JA) on morpho-physiological and biochemical characteristics of strawberry cv. Queen Elisa, under in vitro PEG-induced water stress, a factorial experiment based on completely randomized design (CRD) was conducted. PEG-induced water stress was imposed using polyethylene glycol (PEG6000) at three levels (0, 5 and 7% w/v), under three levels of JA application (0, 0.01 and 0.05 mM). The results indicated that PEG-induced water stress negatively impacted all studied morphological traits except for shoot fresh and dry weight. Furthermore, PEG-induced water stress had a decreasing effect on physiological traits including relative water content (RWC), photosynthesis pigments, membrane-stability index (MSI), and total proteins while it increased the activity of peroxidase (POD) and superoxide dismutase (SOD) enzyme and the content of malondialdehyde (MDA), hydrogen peroxide (H2O2), and proline. JA application showed an interaction effect with PEG-induced water stress on all studied traits except for SOD, POD, and total carbohydrate. Besides, based on the heat-map and principal component analysis results, three distinct groups were observed for physio-biochemical traits. Accordingly, the most effective treatment was the application of 0.05 mM JA under non-stressed condition. Altogether, the strawberry plants treated with higher JA concentrations could effectively cope with PEG-induced water stress adverse effects. Meanwhile, JA application improved strawberry growth attributes under both stress and non-stress conditions. In conclusion, the application of JA can be suggested as an effective way to alleviate deleterious impacts dehydration stress on strawberry under in vitro conditions. In vitro culture was used to study the effects of JA in strawberry under stress. PCA and heat map showed that relationships among studied parameters changed.

This research was carried out to evaluate the effects of copper nanoparticles (CuNPs) on the postharvest physiology of carnation and chrysanthemum cut flowers. Synthesized CuNPs were applied at 10 and 20 mg L-1 to both cut flowers by the pulsing method. The physicochemical characteristics and the activity of antioxidant enzymes were measured on 0, 3, 6 and 9 days along the vase life. According to heat map analysis, changes in measured parameters were affected by flower type > vase period > CuNPs concentration. Results also showed that treating the two species of cut flower with CuNPS by the pulse treatment improved the relative fresh weight (RFW), vase solution uptake (VSU), membrane stability index (MSI), flower diameter and total soluble carbohydrate (TSC). Meanwhile, a decrease in both bacterial population of the stem end and the hydrogen peroxide (H2O2) was observed. In comparison with the control, CuNPs at 20 mg L-1 by pulse treatment almost increased the vase life in both cut flowers by 30%. Resumo Esta pesquisa foi realizada para avaliar os efeitos das nanopartículas de cobre (CuNPs) na fisiologia pós-colheita de flores de cravo e crisântemo. Foram aplicados 10 e 20 mg L-1 CuNPs sintetizados em ambas as flores cortadas pelo método de pulse. As características físico-químicas e a atividade das enzimas antioxidantes foram medidas aos 0, 3, 6 e 9 dias ao longo da vida útil de vaso. De acordo com a análise do mapa de calor, as alterações nos parâmetros medidos foram afetadas pelo tipo de flor > período no vaso > concentração de CuNPs. Os resultados também mostraram que o tratamento das duas espécies de flores cortadas com CuNPS pelo tratamento por pulso melhorou o peso fresco relativo (RFW), captação da solução do vaso (VSU), índice de estabilidade da membrana (MSI), diâmetro da flor e carboidrato solúvel total (TSC). Enquanto isso, foi observada uma diminuição na população bacteriana da extremidade do caule e no peróxido de hidrogênio (H2O2). Em comparação com o controle, CuNPs a 20 mg L-1 por tratamento por pulso quase aumentou a vida do vaso em ambas as flores cortadas em 30%.

The response of ‘Kurdistan’ and ‘Paros’ strawberry cultivars to potassium silicate (K2O3Si) under sodium chloride (NaCl) salinity stress was studied in terms of vegetative parameters, sodium (Na) a...

Salinity is a major abiotic stress that adversely affects turfgrass growth. Clinoptilolite zeolite, a silicon (Si)-rich mineral, may allow these plants to cope with salinity. Therefore, in the present study, the effects of ordinary clinoptilolite zeolite (OZ) and potassium-enriched clinoptilolite zeolite (K-EZ) on the growth of perennial ryegrass (Lolium perenne L.) were assessed under salinity stress. Perennial ryegrass seeds were cultured in soil mixtures amended, or not, with OZ or K-EZ, then exposed to three salinity levels (0, 50 or 100 mM NaCl) for three months. Control plants were grown in the same soil mixture without zeolites, but not exposed to salinity. In salinity, the application of both types of zeolite significantly decreased Na content by 44.36% and 21.31%, but increased K content by 272.34% and 81.59%, as well as the K/Na ratio by 590.47% and 129.43%, in shoots and roots, respectively, compared to the no-zeolite treatment. Similarly, Si content in shoots increased by 28.33%. Amending the soil mixture with zeolite, especially K-EZ, enhanced relative water content, membrane stability index, total chlorophyll content, total soluble proteins, peroxidase and superoxide dismutase activities but reduced the contents of total soluble carbohydrates, hydrogen peroxide, and malondialdehyde in saline conditions. Shoot and root dry weight, root volume and root/shoot ratio also improved. Soil amendment with both forms of zeolite, as a Si-rich mineral, partially offset the negative impacts of salinity on perennial ryegrass, although K-EZ had more noticeable positive and beneficial effects. The amendment of growth media with zeolite may be an effective sustainable management practice for turfgrass used in landscaping and sports fields exposed to saline water.

The physiological and metabolic processes involved with grapevine growth and production are influenced by key macro- and micronutrients. Potassium is an essential plant nutrient that affects growth and fruit quality. In this study, the impact of foliar spraying of potassium sulfate (K2 SO4 ) on qualitative characteristics of grape berries was evaluated in the cultivar 'Rasha', a commonly cultivated cultivar in Kurdistan province of Iran. Leaves of the fully grown vines were sprayed with each of the 1.5 and 3 g L-1 K2 SO4 solutions once (1 month after petal senescence) and twice (15 days after first spraying). The control plants were sprayed with distilled water. Various biochemical contents and enzyme activities on the ripe berries were analyzed.; Results: Significant increases in anthocyanin, total protein content, and antioxidant enzyme activities were observed in the berries treated twice with 3 g L-1 K2 SO4 . Concentrations of total carbohydrate, phenol, and antioxidant activity in berries sprayed with K2 SO4 were higher than in the controls. We observed a strong correlation between antioxidant activity and different phenolic compounds.; Conclusion: These findings suggest that K2 SO4 treatment influences biosynthesis of phenolic compounds and antioxidant enzymes. Thus, treatment by K2 SO4 could improve nutritional and qualitative attributes of grape. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

Dust pollution can negatively affect plant productivity in hot, dry areas with high insolation during summer. To understand the effect of water-deficit and its interaction with dust pollution on vegetative and physiological changes in grapevine ʻBidaneh Sefidʼ, two-year-old plants were subjected to drought stress (-0.1 and -1 MPa) and dust treatment in a greenhouse during 2013 and 2014. The results showed that dust had a significant negative effect on the number of leaves, shoot length, root and shoot dry weights, and total dry weight under both drought and well-irrigated conditions. Dust, when applied in combination with drought, caused severe growth reduction. Leaf relative water content (RWC) and membrane stability index (MSI) were reduced under dust and drought stress, while soluble carbohydrate, proline, malondialdehyde (MDA) and H2O2 concentrations increased. Furthermore, dust application resulted in characteristics similar to those induced by water-deficit stress and intensified vegetative and physiological changes when applied together. Dust and drought treatments increased peroxidases and ascorbate peroxidase activities when compared to the control. The results indicate that dust has an adverse effect on the growth and physiology of grapevine and plays a negative role in the response of grapevine to drought stress.

Exogenous application of certain compounds can reduce the harmful effects of water stress. This experiment was carried out to study the effects of β-amino butyric acid (BABA) on the morpho-physiological traits and antioxidative enzyme activity in sweet cherry (Prunus avium L. cv. Takdaneh Mashhad) under water-stress conditions. Sweet-cherry saplings were exposed to three water-stress treatments (well-watered, −0.6 and −1.2 MPa based on soil water potential) and three root-applied BABA treatments (0, 0.8 and 1.6 mM). The results indicated that drought stress decreased the number of leaves, leaf area, leaf dry weight, root volume, root dry weight, total dry weight, trunk dry weight, trunk diameter increment, relative water content (RWC), membrane stability index (MSI), leaf chlorophyll and carotenoids content. It increased free proline, total soluble sugars (TSS), malondialdehyde (MDA), hydrogen peroxide (H2O2), protein content and activity of peroxidase (POD) and ascorbate peroxidase (APX) content of leaves. Water-stress conditions with the application of BABA reduced the number of leaves, leaf dry weight, leaf area, the content of MDA and H2O2, but enhanced the trunk diameter increment, root volume, root dry weight, total dry weight, RWC, MSI, chlorophyll a, b and total chlorophyll, carotenoids, free proline and TSS, POD and APX activities in leaves compared to unprimed water-stressed plants. Application of BABA, particularly at 1.6 mM, had a significant effect on some morpho-physiological and biochemical attributes and mitigated some detrimental effects of water stress.

We aimed to understand the impact of two potassium silicate (K 2 O 3 Si) levels (1000 and 1500 ppm) on vegetative growth, physiological parameters and fruit yield of two strawberry cultivars under saline (50 mM NaCl) and non-saline conditions during 2014 and 2015. Supplementary Si counteracted the negative effects of salinity on dry matter, leaf area, and root length and volume. Leaf relative water content and chlorophylls content were also improved by application of K 2 O 3 Si under salinity. NaCl imposed oxidative damages to cell manifested as decreased membrane stability index (MSI) as well as increased malondialdehyde (MDA) and H 2 O 2 content. Higher MSI as well as lower MDA and H 2 O 2 in Si-supplied plants representing a systemic palliative effect of Si to salinity induced cellular injuries. Salinity led to an increase of proline and soluble carbohydrates suggesting a physiological osmotic strategy to increase salt tolerance. Reduction of proline content further supports the beneficial roles of Si in alleviation of the adverse effects of salt stress. Significant increase in activity of peroxidase (POD) and superoxide dismutase (SOD) enzymes was only observed during 2015 under saline conditions. The induction of antioxidant enzymes coincided with a decrease in concentration of MDA and H 2 O 2 . Salinity decreased fruit yield in both cultivars with a drastic reduction in Paros. K 2 O 3 Si nutrition could recover yield loss with almost a 50% increase in fruit weight per plant. Overall, our results suggest that drenching potassium silicate in the nutrient solution of strawberry plants could be considered as a routine strategy to maintain strawberry growth and yield under salinity.

In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vitro condition, the median effective concen- tration (EC₅₀) values (ppm) of plant essential oils and fungicides were measured. In greenhouse, soil infested with Phytophthora species was treated by adding 50 ml of essential oils and fungicides (100 ppm). Disease severity was determined after 28 days. Among two tested plant essential oils, C. citratus had the lowest EC₅₀ values for inhibition of the mycelial growth of P. capsici (31.473), P. melonis (33.097) and P. drechsleri (69.112), respectively. The mean EC₅₀ values for Metalaxyl-Mancozeb on these pathogens were 20.87, 20.06 and 17.70, respectively. Chemical analysis of plant essential oils by GC-MS showed that, among 42 compounds identified from C. citratus, two compounds β-geranial (α-citral) (39.16%) and z-citral (30.95%) were the most abundant. Under the greenhouse condition, Metalaxyl-Mancozeb caused the greatest reduction in disease severity, 84.2%, 86.8% and 92.1% on melon, cucumber, and pepper, respectively. The C. citratus essential oil reduced disease severity from 47.4% to 60.5% compared to the untreated control (p≤0.05). Essential oils of O. basilicum had the lowest effects on the pathogens under in vitro and greenhouse conditions. These results show that essential oils may contribute to the development of new antifungal agents to protect the crops from Phytophthora diseases.

Drought is one of the critical environmental stresses that affect growth and development of plants. Plants are damaged directly and indirectly under drought stress. Increasing water stress tolerance in plants is crucial. The aim of this study was to investigate the effects of different water stress levels (-1, -5, and -10 bars) and paclobutrazol application (0 and 50 mg-1) on strawberry cv. Paros. According to analyses of variance there were significant effects of drought stress and paclobutrazol application on leaf area, leaf dry weight, leaf relative water content (RWC), cell membrane stability index (MSI), proline and protein content of leaves. Leaf area, leaf dry weight, leaf relative water content and cell membrane stability index decreased in drought stress, especially at -10 bars. Proline and protein contents were enhanced by increasing water stress levels. Paclobutrazol application increased leaf relative water content and cell membrane stability index, proline and protein contents of leaves. Leaf relative water content was 68.77% in -10 bars drought stress that increased to 79% in paclobutrazol treatment. Also, cell membrane stability index was 69.65% in severe drought stress and reached to 77% in paclobutrazol treatment. According to the results pacloburazol is a benefit substance to ameliorate drought stress effects in strawberry cv. Paros.

The physiological and metabolic processes involved with grapevine growth and production are influenced by key macro- and micronutrients. Potassium is an essential plant nutrient that affects growth and fruit quality. In this study, the impact of foliar spraying of potassium sulfate (KSignificant increases in anthocyanin, total protein content, and antioxidant enzyme activities were observed in the berries treated twice with 3 g LThese findings suggest that K

To consider the interaction effects of salinity (0 and 50 mM) and humic acid (0, 150 and 300 ppm) on vegetative, yield and physiological characteristics of Kurdistan and Paros strawberry cultivars, an experiments were conducted during 2014–2015 growing seasons. Implementation of salt stress decreased almost all vegetative traits in line with the change in some studied biochemical and physiological responses. Under salt stress conditions, more Na+ accumulated in shoot and root of both cultivars while K+ content decreased. In contrary, humic acid reduced Na+ and increased K+ accumulation under salinity treatment. Salinity stress increased leaf necrotic area, the activity of antioxidant enzymes, hydrogen peroxide, lipid peroxidation, proline and total soluble carbohydrates while the supplementation of nutrient solution with humic acid recovered these traits and increased salt tolerance index. Leaf relative water content, membrane stability index, chlorophyll content, total biomass and yield were also negatively affected by salt stress, however, humic acid mitigated the adverse effects of salinity on these traits. Principle component analysis (PCA) based on vegetative, physiological and yield traits across two strawberry cultivars showed that 96 and 87.1% of the total variance were explained by the first two principal components in 2014 and 2015, respectively. Moreover, The heatmap from hierarchical clustering analysis (HCA) showed that all the measured parameters under different humic acid and salinity treatments in 2014 and 2015 were grouped into four clusters. Similar trends were also observed in the PCA for almost all of the studied traits. One interesting result from the HCA and PCA score plot was that the related attributes (i.e. hydrogen peroxide, lipid peroxidation) were grouped together. According to our study strawberry plants fed with humic acid were able to compensate for the negative effects of salinity.

In the present study, multiplication efficiency of Alstroemeria ligtu hybrid was investigated. Bases of the first seedling leaves grown in vitro were used as initial explants. The explants were cultured in the MS media containing 3% sucrose, 0.7% agar at pH 5.8, five N6-benzylaminopurine (BAP) concentrations (0, 0.5, 1, 1.5 and 2 mg·1-1) and three indole-3-butyric acid (IBA) concentrations (0, 0.1 and 0.2 mg·1-1). The cultures were incubated at 21 ± 2 °C under photoperiod 16/8. After three subculturings (3 weeks-long each) the number of rhizome, shoots, buds, leaves, and roots, length of shoots and roots were recorded. Adventitious shoots formed directly on the leaf bases without callus intervention. Their number was affected by BAP concentrations. The highest shoots number, six per explants, was obtained at 1 mg·1-1 BAP and 0.1 mg·1-1 IBA. The shoot length decreased with the increasing concentration of BAP. The highest root number (2.7) was formed on shoots cultured on the MS medium containing 0.5 mg·1-1 α- naphthalene acetic acid, and the highest rhizome number (2.2) was formed on the medium with 0.5 mg·1-1 BAP. In vitro rooted plantlets were able to survive and acclimatize in the greenhouse.

The antifungal activity of the essential oils of ajowan, fennel and caraway was evaluated in vitro and in vivo conditions against growth of Alternaria alternata (Fr.: Fr.) Keissler. and Penicillium digitatum Sacc., two postharvest pathogens of tomato fruits. In vitro tests showed that ajowan and fennel oils exhibited the highest antifungal activity against A. alternata and P. digitatum, respectively. But caraway exhibited poor antifungal activity against two fungal species tested. Ajowan oil possessed the highest antifungal activity among tested oils in in vivo condition. Gas chromatography–mass spectrometry analysis of essential oils revealed that thymol (63%), trans-anethole (64%) and 2-caren-10-al (34%) were the main components of essential oils of ajowan, fennel and caraway, respectively. Therefore, essential oils may be used as an alternative for the synthetic chemicals for control of postharvest phytopathogenic fungi and for increasing the shelf life of plant products. PRACTICAL APPLICATIONS Because the plant essential oils have low mammalian toxicity, are biodegradable, multifunctional, nonpersistent in the environment and are cheap to produce, the possibility of developing essential oils for use in crop protection may be an attractive venture. This study demonstrates the potential of essential oils as antifungal preservatives for tomato fruits that are susceptible to postharvest decay caused by fungi. Examination of various concentrations of essential oils from ajowan (Carum copticum L.), fennel (Foeniculum vulgare Mill.) and caraway (Carum carvi L.) on Penicillium digitatum and Alternaria alternata in this study showed promising prospects for the utilization of essential oils. In vivo experiments showed that essential oils used could reduce postharvest diseases on tomato fruits caused by P. digitatum and A. alternata. So, essential oils can be used as a potential source of sustainable eco-friendly botanical fungicides, after successful completion of wide-range trials.