فصلنامه فرآیند و کارکرد گیاهی
سال دوازدهم شماره 3 (پیاپی 56، Aug and Sep 2023)

The use of indigenous extremophilic bacteria with plant growth-promoting haloalkaliphilic properties will help to cope with biotic and abiotic stresses. The present study focused to investigate the effect of these bacteria to induce salinity resistance in almond rootstocks under soil salinity and alkalinity and compare it with non-stress conditions. The roots of 108 Garnem rootstocks in four different soils (2, 4, 8, and 16 dS m-1) were inoculated with two bacterial strains and sterilized control from three groups of halophilic, alkaliphilic, and haloalkaliphilic isolated from the rhizosphere of almond’s cultivation sites. Plant growth-promoting properties, including tri-indole acetic acid production, phosphate mineral dissolution, and exo-polysaccharide production, were measured for alkaliphilic isolates (213.33, 127.55, and 578.11 mg L-1), haloalkaliphilic isolates (77.13, 73.99, and 284.54 mg L-1), and halophilic isolates (15.98, 40.19 and 35.90 mg L-1, respectively). The inoculated plants with halophilic bacteria were found to better grow compared to other inoculated plants. In addition, these plants accumulated more chlorophyll, sugar, and proline. The root fresh and dry weights were maximum by the haloalkaliphilic bacteria inoculation. The alkaliphilic and halophilic bacteria also caused a higher increase in fresh and dry weights of shoots. As well, root and shoot moisture contents were the highest ones in the 16 and 8 dS m-1 salinity by haloalkaliphilic inoculation. In general, the application of haloalkaliphilic bacteria was found to have a better effect on root growth and halophilic bacteria in the morphological and physiological properties of almond rootstocks. Compared with 8 dS m-1 and other salinity levels, extremophile bacteria had a stronger effect on soil salinity and alkalinity mitigation for almond rootstocks at 16 dS m-1 salinity.

Polyploidy, as one of the main factors in the speciation and adaptation of plants, can increase the pharmaceutical constituents of medicinal plants. Salvia officinalis L. is a perennial plant from the Lamiaceae family with various medicinal properties. This study aimed to analyze and compare some phytochemical characteristics, such as essential oil and phenolic acid contents and examine the expression of some genes involved in the biosynthesis pathway of phenolic acids in diploid and induced tetraploid plants of S. officinalis by GC-MS and real-time PCR, respectively. The results revealed that S. officinalis essential oil components such as α-pinene, camphene, camphor, borneol, and fenchyl acetate were significantly increased (P < 0.05) in tetraploid plants compared with diploids. Furthermore, tetraploidy increased the level of phenolic acids of gallic, caffeic, rutin, coumaric, rosmarinic, quercetin, cinnamic, apigenin, and chlorogenic acids in S. officinalis. Also, based on RT-PCR results, a higher expression of C4H (Cinnamate 4-Hydroxylase), PAL1 (Phenylalanine ammonia-lyase), 4CL (4-Hydroxycinnamate coenzyme A ligase), TAT (Tyrosine aminotransferase), HPPR (Hydroxyphenylpyruvate reductase), and CYP98A14 (cytochrome P450-dependent monooxygenase) genes involved in their biosynthesis pathway was observed tetraploids compared with diploids. The results confirmed that polyploidy breeding in medicinal plants could be applied to enhance secondary metabolite production.

Lisianthus flowers are an important cut flower in the international markets. This study was conducted to evaluate effects of peel extract of key lime (Citrus aurantifolia) (as extracted by three different solvents including deionized water, ethanol and methanol) on the vase life and quality of cut lisianthus flowers. The experiments were conducted in a completely randomized design with 10 treatments containing 0, 15, 25 and 50 ppm peel extracts of C. aurantifolia in three solvents consisted of deionized water, methanol and ethanol with three replicates. The results showed that effect of C. aurantifolia peel extracts on the vase life of lisianthus cut flowers significantly varied according to the extraction methods. The water extracted key lime peels significantly increased the vase life (13.66 days) and resulted in the highest fresh weight of the flowers, petal water content. Whereas ethanolic extracts reduced the vase life and water content of the inflorescence. The best quality of flowers during vase life period was obtained from deionized water extracts at 25 and 50 ppm concentrations. Results of our investigation indicated that method of extraction plays an important role in effectiveness of extract. Deionized water was the best one for extraction of active compounds from C. aurantifolia. No limitations were founded.

Salinity stress is one of the most important abiotic stresses in arid and semi-arid climates that limit crop plants' growth and development. Salicylic acid (SA) is an endogenous plant growth regulator that can regulate physiological processes and improve the plant's tolerance to stress. A factorial experiment based on a completely randomized design was carried out to investigate the effects of different levels of SA (0, 0.5, and 1 mM) on some growth and biochemical parameters of spinach under salinity stress (0, 40, and 80 mM). Our findings showed that salinity negatively affected growth traits and photosynthetic pigments while SA increased them. For example, under severe salinity stress, a concentration of 1 mM SA increased shoot length by 23%, and 0.5 mM SA enhanced both the fresh and dry weight of the root by 26%. Also, under moderate and severe salinity stresses concentration of 1 mM SA increased shoot dry weight by 130 and 69%, shoot fresh weight by 52 and 42%, chlorophyll a by 53, and 86%, chlorophyll b by 79 and 112%, total chlorophyll by 63, and 96%, carotenoids by 63 and 64%, soluble sugars by 44 and 13%, anthocyanin by 48 and 25%, respectively in comparison to the control plants. In conclusion, a concentration of 1 mM SA decreased negative effects of salinity stress on evaluated growth and biochemical parameters more than 0.5 mM, and improved tolerance of the spinach plants to the salinity stress by an increase in plant growth, total chlorophyll and carotenoids, soluble sugars, and anthocyanin.

Water deficit is one of the most important stresses that has limiting effects on growth and crop productivity. One of the best methods for facing drought is seed priming with optimal concentrations of plant growth regulators. Salicylic acid (SA) is an important signal molecule modulating plant response to stress, which enhances tolerance to multiple stresses in plants, including drought. To analyze the effects of various concentrations of salicylic acid on some physiological and morphological traits as well as flower and fruit production of tomato, Riugerand variety, under water deficit conditions, a factorial experiment in a complete randomized design with three replications was carried out in the greenhouse. Six levels of salicylic acid (untreated seeds or control, zero SA or hydro-prim, 500, 1000, 1500, and 2000 mM) and three levels of drought stress (including water holding at field capacity [FC] of pots and water stress at 70% and 50% FC) were used as experimental treatments. Results showed that priming with salicylic acid increased plant height, leaf area, relative water content, and chlorophyll index compared to untreated plants. However, drought stress drastically decreased all these measured traits. 500 mM SA led to an increase in the number of flowers and fruits per plant as compared to other water deficit treatments. Tomato fruit characteristics, including pH, Brix, and EC, were significantly increased by drought stress. However, the application of SA decreased these traits, especially at 500 mM which enhanced the quality of the fruit. In conclusion, seed priming with suitable concentrations of SA (500 to 1000 mM) can be used as an appropriate strategy for the improvement of growth and fruit parameters of tomatoes under water deficit conditions.

In order to evaluate the effect of mycorrhizal fungi on the yield and active ingredient of borage (Borago officinails L.) under water deficit stress, the experiment conducted as split-plot in randomized complete block design with 3 replications in the Boyerahmad region at year 2015. The experiment factors were considered of irrigation levels (main-plot) as irrigation after S1 =30, S2 =60, S3 =90, S4 =120 and S5 =150 mm water evaporation from evaporation pan class A and mycorrhiza fungi (sub-plot) were considered at the levels of non application (NM), application with mycorrhiza fungi species of Glomus mosseae (GM) and Glomus intraradices (GI). The results showed that the effect of water stress on flower yield of borage was significant at level 1% and in the treatment 30 mm evaporation was obtained the highest yield of flower (188.9 kg/ha). The most flower yield was obtained in application treatments of mycorrhizal fungus G. Mossea and G. intraradices respectively with flower yield 147.2 and 145.5 kg/ha compared to non application of mycorrhizal fungus. The interaction of water stress and mycorrhiza fungi on phytochemistry traits of mucilage weight and mucilage percent of flower borage was significant at level 1%. The treatments S30N.G, S30GM, S30GI, S90N.G, S90GM and S90GI respectively with the weight of flower mucilage 11.77, 12.47, 12.06, 10.32, 12.34 and 11.78 kg/ha with the highest value were in first class (A). Treatments S30N.G, S30GM, S30GI, S60N.G, S60GM, S60GI, S90GM, S90GI and S120GM respectively with flower phosphorus content 268.4, 290.1, 275.6, 253.9, 252.9, 282.9, 268.9, 192.4 and 174.3 ppm had the highest amount. The treatments S90GM and S90GI respectively with water use efficiency 0.0178 and 0.0176 kg/m3 had the highest amount. The application of mycorrhizal fungi generally reduced the negative effects of water stress in this study and could increase flower yield, water use efficiency, percentage and weight of flower mucilage of borage in this research.

Stevia rebaudiana Bertoni, (Asteraceae) is a well-known plant with its natural sweetening compounds named as steviosides. In the present work, Stevia plants was treated with 2 and 4 days of cold stress at 4 °C and then total stevioside level, content of  certain steviosides and electrophotetic pattern of proteins were evaluated using spectrophotometry, HPLC and SDS-PAGE methods, respectively. The results indicated that cold treatment (4 days) caused a 40% increase in total sativoside content of Stevia rebaudiana. The results of HPLC analysis showed that the amount of Rebaudioside A, a known stevioside, increased significantly after 2 days of cold treatment as 70% more than control. The SDS- PAGE analysis of the plant proteins revealed that some protein bands density were increased in the cold treated groups of Stevia compared with control group. These bands might be related to heat chock proteins. From a practical point of view, cold treatment can elevate Rebaudioside A in Stevia cultivation. This compound has large applications in heart-healthy foods and debating cookies as food additive.

Salinity stress is one of the serious environmental stresses that can influence crop growth and physiological and biochemical parameters. In this study, the role of vesicular and arbuscular mycorrhizal fungi ˈGlomus mosseaˈ and the putrescine polyamine in modulating the negative effects of salinity stress on physiological and biochemical parameters of strawberry plants were investigated. This study was done as a factorial experiment based on a completely randomized design with three replications in 2021 in the research greenhouse at the University of Jiroft. The studied factors included mycorrhizal fungi (0 and 30 g), putrescine (0 and 1.5 mM), and salinity levels (0 and 60 mM NaCl). Sodium (Na+) and potassium (K+) ions, and K+/Na+ in leaves and roots, photosynthetic pigments, relative water content (RWC), membrane stability index (MSI), reactive oxygen species (ROS), soluble sugar, anthocyanin, and proline in leaves were investigated. Simultaneous use of mycorrhizal fungi and putrescine by the more (170% compared to the control) accumulation of Na+ in the roots decreased their transfer to the leaves and by increasing the ratio of K+/Na+ in the leaves, it reduced the accumulation of ROS and, as a result, increased the MSI and also maintained leaf photosynthetic pigments. Salinity increased total soluble sugars and the use of putrescine caused the accumulation of proline and anthocyanin in the leaves. Therefore, modulation of the negative effects of salinity stress by mycorrhizal fungi and putrescine indicates successful adaptation of strawberry plants to salinity stress in the presence of mycorrhizal fungi and putrescine. Finally, our results recommend the use of mycorrhizal fungi in saline areas and provide an important perspective for the use of putrescine in modifying salinity tolerance.

The idea was to assay the salinity (0, 50 and 100 mM) impacts on Coriandrum sativum by the foliar application of nano-Zn, FeSO4, MgSO4 and methanol in possibly the salinity stress side-effects. A factorial experiment was arranged based on a completely randomized design with three replications in pot at Azarbaijan Shahid Madani University. The results revealed that salinity × foliar treatment significantly affected plant dry weight, relative water content, catalase activity, and elemental content of plants. The top recorded data (P≤5%) for, plant dry weight and chlorophyll b content was with non-salinity × all foliar treatment. No-salinity and NaCl50mM × methanol foliar application increased K content in plant. 50 mM NaCl × FeSO4 and nano-Zn spray increased catalase activity. Foliar spray with methanol, FeSO4 and nano-Zn × no salinity increased N content. The highest relative water content belonged to no salinity × FeSO4 and nano-Zn and NaCl50 mM × FeSO4 treatment. The top content of Fe, P, Ca and K/Na were recorded at non-saline conditions. 50 mM NaCl increased the essential oil content of the plant. 100 mM salinity treatment increased malondialdehyde, H2O2, Na and proline contents. Foliar treatment with FeSO4 and MgSO4 increased the essential oil content of the plant. As well Coriandrum sativum was sensitive plants to salinity, and foliar treatments especially FeSO4 and nano-zinc ameliorated the adverse side-effects of salinity in plants.

Rosa damascena Mill. is the most important scented rose species which cultivated for essential oil production in the world. The objective of the present study was to understand how different harvest dates influenced the essential oil yields and chemical compounds in petals of Rosa damascena Mill. planted for the first time under calcareous soil conditions, Sa′adat Shahr region. In the current survey, flowers were collected four times with three replications from four years old plants between 05:00 and 06:00 AM (2nd, 9th, 16th and 23rd of May, 2020). The essential oils of samples were extracted by hydro-distillation system (Clevenger apparatus) and were analyzed by a combination of GC-FID and GC-MS techniques, to check for chemical variability. The essential oil content of flowers harvested at different times ranged from 0.046% to 0.082% (w/w). The number of identified compounds were 30, of which 21 were common. The highest content of citronellol + geraniol (60.9 %), which are the most important constituents of its essential oil, was observed when the flowers were harvested in the 2nd of May. However, the lowest content of them (40.6 %) was found in the flowers of the fourth week of harvesting. n-nonadecane and n-heneicosane continuously increased from the first week (17.4 %) to the fourth week (34.8 %) of the harvest. This experiment revealed that different harvest dates can significantly modify the performance and composition of Damask rose’ essential oil. Moreover, calcareous soil conditions could be used to obtain essential oil of Rosa damascena Mill.