نشریه فیزیولوژی محیطی گیاهی
پیاپی 55 (پاییز 1398)

Queues castanifoliais one of the most demanded species for reforestation in Golestan province. It is necessary to produce appropriate seedlings in nurseries.  This study was carried out to determine the effect of perlite on soil on growth and physiological responses of Queues castanifolia seedlings under water deficit stress. A factorial experiment was conducted as randomized complete block design in greenhouse condition of agricultural and natural resources research Center in Gorgan, 2015. Perlite treatments in 4 levels (0, 15, 25 and 35% (V/V)) was added in soil and water stress in 3 levels (40, 70 and 100% irrigation at field capacity) for 5 months were applied in the pot experiment. Some parameters including gas exchange (photosynthesis, stomatal conduction and transpiration) and leaf water potential of seedlings, diameter and height growth and dry weight of root, stem, leaf, and seedlings were measured in different treatments at the end of the experiment period. The results showed that all parameters were affected by different levels of irrigation and perlite. Water deficit to 40% FC reduced 51% and 68% of photosynthesis and stomatal conductance respectively. The highest diameter and height growth and dry weight of the seedlings were observed in 25% and 35% (V/V) perlite application under normal and stress conditions, respectively. The use of perlite alleviated the negative effects of water deficit and ameliorated seedling growth. It could be suggested that perlite application in soil is suitable for the production of desirable seedlings under water deficit condition.

In order to investigate the effect of different levels of of IBA and strains of Pseudomonas fluorescens bacteria, an experiment was conducted as factorial with completely randomized design containing two factors and three replications. In the first factor, effect of three levels of IBA (0, 2000 and 4000 mg/ ml) and in the second one effect of two strains of P. fluorescens (R5 and R64) on olive (Olea europaea cv. conservaliya) were investigated. Results showed that bacterial inoculation with R5 strains increased shoot and root dry weight, total dry weight, nitrogen concentration and phosphorus uptake compared to control, but there was no significant difference between R5 and R64 strains in terms of total chlorophyll. The 2000 mg/ml IBA also increased shoot and root dry weight, nitrogen concentration, total chlorophyll and total dry weight related to control, while the maximum phosphorus uptake was obtained in 4000 mg/ml IBA. The interaction effect of IBA and bacteria showed that in morphological characteristics and uptake and concentration of elements, maximum average were obtained in 2000 mg/ml IBA and R5 strain treatment. According to the obtained results, the application of both of 2000 mg/ml IBA and R5 strain for improvement of rooting is recommended.

In order to investigate the effects of foliar application of calcium (Ca), potassium (K) and Volck oil separately or in combination on budburst and cold tolerance related physiological indices in Bidaneh-Sefid grapevine, a randomized complete block design with four replications was conducted in 2017 in a commercial vineyard located in Abasobad of Khondab town of Markazi province. The treatments included control, Volck oil, Volck oil + Ca, Volck oil + K, K, Ca, Ca + K and Volck oil + Ca + K. the vines sprayed with Volck (1%) of calcium (2%) and potassium (3%) in two stages in mid April at the wooly stage and one week later. The traits included days to budburst, ion leakage, peroxidation of membrane lipids, chlorophyll a and b, relative water content, soluble carbohydrates, proline, soluble proteins and phenol. The combined treatment of Volch + Ca + K resulted in 5 day retardant in budburst compared to control vines. The highest concentrations of carbohydrate, phenol and protein were obtained with Ca + K combined treatment, and the lowest ones were observed in both control and Volck oil- treated vines. The highest amounts of chlorophyll a, b, carotenoids and total chlorophyll were obtained from Ca and K treatment and the lowest was observed in Volck oil treatment. The highest concentrations of proline, carbohydrate, and soluble protein were related to Ca + K treatment, and the lowest ones were obtained for control treatment. The highest relative water content, ion leakage and membrane lipid peroxidation were detected in control vines. Therefore, in order to avoid late spring frost in vineyards, the combination of Volck oil + Ca + K was found to be appropriate in vineyards.

In order to investigate the integration effect of organic and chemical fertilizer on vegetative and yield characteristics of sweet pepper (Caspsicum annuum, Var: Traviata), an experiment was conducted on a randomized complete block design with three replications at Ferdowsi University Research Station Mashhad in 2017. Treatments were included control (without adding any fertilizer), NPK fertilizer, animal, vermicompost, vermicompost+chemical, animal+chemical, animal+vermicompost and animal+vermicompost+chemical. The results showed that the application of combined animal and chemical fertilizers significantly increased the morphological and yield components of the plant. The highest plant height, leaf number, leaf area, shoot dry weight, spad index, Fruit length, number of fruits per plant and fruit fresh weight per plant were obtained from combined animal and chemical treatments. Used of combine animal and chemical fertilizer was increased amount of stomata conductance about 45% in compare of control. The highest number of cavities in fruit was obtained from vermicompost treatment and the highest fruit diameter was recorded from combined vermicompost in chemical fertilizer. In general, the results showed that the use combine of animal and chemical fertilizer due to the effect of improving physical and chemical structure of soil, stimulation of some microorganisms and availability of nutrients, lead to increase the morphological traits, yield components and yield of sweet pepper.

For the first time, the effect of pretreatment of time (24 and 96 hours) and pH (7 and 9) at extremely limited carbon dioxide concentration on the exponential growth phase, photosynthetic pigments per cell, absorption shift of chlorophyll, structure and function of phycobilisome, light harvesting to reaction center pigment and photosystem one to photosystem two ratios were studied on stigonematalean cyanobacterium Fischerella sp.FS 18. Results showed that pretreatment treatments cause keeping the exponential growth phase at both 24 and 96 hours and pHs 7 and 9. In the opposite of absorption peak of chlorophyll, cellular pigments show no stable pattern regarding pretreatments. Phycobilisomes was the main point of treatment affects. The pattern of the rode part of phycobilisomes was the same at pretreatment reactions. The shift of phycocyanin was about one and phycoerythrin about nearly three. The highest rate of photosystem one to photosystem two ratio observed at 24 hours’ neutral condition. This changed by the time and caused efficiency decreasing of energy transport in photosynthesis system. Phycobilisome operation change may be a compensational mechanism to reduce the degree of such a decrease.

Heavy metals pollution, especially heavy metals, is one of the major environmental problems. These pollutants involve soil, water and related ecosystems and cause problems for the flora and even humans. Microalgae have many features, which make them ideal candidates for elimination of petroleum pollution and reduction of various heavy metals contaminations. This study was carried out using Calothrix sp., which isolated from polluted areas with the aim of investigating the reduction of nickel as well as studying some physiological behaviors of microalgae. Experiments design was done with the Design Expert software, which considered factors like PH (pH4-9), nickel concentration (5-100 mg/L) and time (30-120 min). The results showed that at pH8 with 80.74 mg/L nickel concentration and 48.24 min was observed the highest nickel uptake (69%). Treatment of algal biomass with different chemical and physical factors in various forms, such as immobilization or use of its metabolites could improve and facilitate the absorption process and create the potential for using these microalgae in subsequent purification systems.

Ferula ovina (Apiaceae) is a perennial rangeland medicinal plant found in the mountainous area of Iran. Due to seed dormancy at maturity and dispersal as well as climate changes in the area, the population of this species has been reduced. Accordingly, in the present study the effects of smoke treatments (aerosol smoke and two methods of smoke extract preparation) on seed germination characteristics of this plant were investigated. Treatments with smoke from the burning of wheat straw were applied after varying periods of cold stratification. Cold stratification changed the level of seed dormancy and increased the rate and percentage of seed germination. Furthermore, aerosol smoke applied after cold stratification significantly increased the rate and percentage of seed germination. The greatest increase (20%) in germination percentage compare to control was observed in seeds that had been cold-stratified for 7 days and exposed to aerosol smoke for two minutes. Smoke extracts with concentrations (1: 1000 - 1: 100 v/v) prepared by the two methods also increased the germination of cold stratified seeds. Hence, the maximum percentage of germination (80%) was obtained for seeds cold stratified for 30 days and treated with 1:1000 dilution of charred straw solution. However, undiluted smoke water decreased the percentage of seed germination after 0 and 30 days of cold stratification and led to abnormal seedling development. In general, the results of this study demonstrated that smoke treatments improve seed germination of cold stratified Ferula ovina seeds.

In order to effect of spermidine and polyethylene glycol pretreatment on germination and some physiological and morphological activity durum wheat under salinity stress a experiment with 20 treatments, three replications was conducted in 60 experimental units. Treatments included five levels of spermidine (zero, 02/0, 05/0, 1/0 and 15/0 mM) and four levels of polyethylene glycol (zero,- 2,- 4 and -5 bar). The results showed that the use of spermidine increased the relative weight contact(RWC) of durum wheat leaf, leaf area ratio, chlorophyll a, chlorophyll b, carotenoids and phenolic compounds .The most of increase in the relative weight been showed in treatments of 02/0 and 05/0 mm of spermidine and the lowest was related to the control of durum wheat at a concentration of 1.0 mM. Maximum leaf area ratio(LAR) seen inconcentration of 0/1mM spermidine, which was statistically significant and the lowest was in 0/15 mM spermidine.The most of effect spermidine showed on the relative growth rate(RGR) by application of 0/15mM and in chlorophylla aregarding .0/5 mM and chlorophull b in the treatment of 0/15 mM, carotenoids in control and total phenolics had in 0/05Mm polyethylene glycole increased chlorophyll a and total phenol but decreased germination and chlorophyll b. Reaction of Polyethylene glycole and spermidine increased percentage of germination, chlorophyll a, chlorophyll b, carotenoids, total phenol and its effect was statistically significant