Breeding and Biotechnology of Plant and Flower
L. Baghazadeh Daryaii; D. Samsampoor; A. Bagheri; J. Sohrabipour
Abstract
Introduction
Fungal Endophytes have symbiosis life within the plant tissues without causing any obvious negative effects. Seaweeds are one of the large and diverse groups of marine plants that play an essential role in marine and oceans ecosystems. Seaweeds show rich diversity of ...
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Introduction
Fungal Endophytes have symbiosis life within the plant tissues without causing any obvious negative effects. Seaweeds are one of the large and diverse groups of marine plants that play an essential role in marine and oceans ecosystems. Seaweeds show rich diversity of associated microorganisms compare with the other multicellular organisms. Citrus species, are amongst the most important evergreen fruit trees, cultivated in many countries worldwide. There are several obstacles for citrus production in southern of Iran that limiting continuity of citrus production. Lack of suitable soil, is one of the main challenges threatening citrus industry in southern of Iran. Similar to other citrus species, the production of Mexican lime is threatened by certain biological stresses (such as pests, plant diseases and weeds) and non-biological stresses (such as salinity, drought, floods, cold and heat stress). Here, we have evaluated the potential of inoculating Mexican lime seedlings with seaweeds fungi endophyte, Aspergillus niger, to improve morphological, biochemical, antioxidant and photosynthesis pigments characterizes. Endophytes are advantageous group of microorganisms that protect plants from biotic and abiotic stresses. One of the alternative ways to restore normal plant growth may be to use plant growth to stimulate endophytes. Endophytes can play an important role in plant growth. Endophytes from marine environment are gaining special interest because of their existence in the harsh conditions of marines and ocean ecosystem such as temperature, light availability, high salinity and osmotic stress. Fungi have already been isolated from various marine habitat, including marine plants, marine invertebrates and vertebrates. Among these organisms, seaweeds are one of the most prevalent sources of marine-derived fungi for chemical studies. The purpose of this study was the isolation of associated fungi with seaweed species in Persian Gulf to investigate morphological and molecular characterization by using PCR amplifications ITS1-5.8S-ITS4 regions and primitive assessment of their potential as bio-fertilizer.
Materials and Methods
The main aim of this study was investigation the role of endophytic fungi (Aspergillus niger), in improving the growth of Mexican lime seedlings. Cladophoropsis membranacea, green seaweed, was collected from coastal region of Bushehr province. Fungal endophytes were isolated and identified based on morphological and molecular methods. Molecular characteristic was investigated using PCR amplification of ITS1-5.8S-ITS4 regions. Mexican lime seeds were sterilized with 0.5% sodium hypochlorite for 20 minutes and then completely distilled three times with distilled water. Seedlings pots containing autoclaved soil were placed in the greenhouse of the Faculty of Agriculture, Hormozan University. Isolated fungi by MT420720 accession number was used as bio-fertilizing agents in eight months old Mexican lime seedlings. The suspension was adjusted to a concentration of 1×106 cell per ml. For better contact of seedlings with fungi, inoculation was performed three times. After three months, morphological (trunk diameter, stem length, root length and width, leaf and branch number, leaf, stem and root dry and fresh weight), biochemical (Protein, MDA and SPAD), antioxidant (CAT, POD, SOD, APX and Gr enzymes activity) and photosynthesis pigments (Chlorophyll a, Chlorophyll b, Total Chlorophyll and Carotenoids) characterizes in treated Mexican lime seedlings were analyzed. The experiment was arranged in randomized complete design with three replications. Analysis of variance of traits was performed using SAS software version 9.4 and the means were compared using LSD method with a probability level of P≤0.05.
Results and Discussion
The genera of Aspergillus was the most frequent isolates of the isolated fungi. The results show that most traits were significant compared with control. For example, leaf number (144.42%), root fresh weight (144.13%), stem fresh weight (94.85%) and root width (105.55%) were significantly higher compared with control (P>0.001). Fungal inoculation can significantly improve the photosynthesis pigments such as chlorophyll a (10.98%) and carotenoids (40.62%) (P>0.001) compared with control. In antioxidant capacity of seedling, CAT, POD, SOD, Gr and APX enzymes were analyzed. Fungal inoculation can increase the enzymes activity. For biochemical traits, fungal inoculation can significantly increase SPAD number and decrease MDA in inoculated seedlings compare with control (P>0.001).
Conclusion
The results showed that the use of entophytic fungi increased the growth of Mexican lime seedlings. Thereby it can be used as an effective tool for growing salinity-sensitive plants such as Mexican lime in saline conditions.
Z. Izadi; A. Rezaei nejad
Abstract
Introduction: While Iron (Fe) is the fourth most abundant element in the earth’s crust, it is not easily available for plant roots. Therefore, Fe deficiency is one of the major limiting factors for plant growth and development in calcareous soils worldwide. Fe deficiency are also predominant in many ...
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Introduction: While Iron (Fe) is the fourth most abundant element in the earth’s crust, it is not easily available for plant roots. Therefore, Fe deficiency is one of the major limiting factors for plant growth and development in calcareous soils worldwide. Fe deficiency are also predominant in many areas of Iran. It is an essential micronutrient for plants that play vital roles in many metabolic processes. Fe is a component of a number of molecules such as Fe-sulfur (Fe-S) and heme Fe proteins, which are required for photosynthesis, respiration and N2 fixation. However, the possibility of using split-type fertilization at different growth stages during development has been explored in other plant species for macronutrients N, P, and K. The aim of this work was to test the hypothesis that it may be feasible to decrease Fe-chelate inputs, by studying the effect of gradually increasing of Fe concentration during Calendula officinalis growing period.
Materials and Methods: In order to study the effect of gradual increase of Fe concentration during Calendula officinalis growing period, an experiment was carried out as a completely randomized design with four replications (pots) at research greenhouse of Faculty of Agriculture, Lorestan University, in 2017. Treatments contained three levels of Fe (Fe-chelate Fe (III)- Ethylenediamine-N, N' –bis ((2-hydroxyphenyl) acetic acid): 4, 20 µM and staircase method. Staircasetreatment included increase of Fe concentration, so that at first week plants received 4 µM Fe then 2 µM was added to Fe concentration weekly, to reach 26 µM. Some morphological, physiological parameters, flower characteristics and gas exchange had measured. Data of all measured parameters were subjected to analysis of variance using the SAS software (9.1.3, SAS Institute Inc.), and means were compared using a Duncan test at P≤ 0.05.
Results and Discussion: Results showed that the application of 4 µM Fe led to higher root volume, and peroxidase activity. Romera et al. (2011) reported that under Fe deficiency, strategy of plants developed morphological changes in their roots and up-regulated the expression of Fe acquisition genes. Under Fe deficiency some phytohormones such as ethylene and auxin will increased. Both hormones play pivotal role in the development of sub-apical root hair and transfer cells. Sepahvand et al (2017) investigated the effect of ascorbic acid on pelagonium graveolens characteristics under Fe deficiency and found that peroxidase activity increased under Fe deficiency. Application of ascorbic acid led to decrease peroxidase activity. Maximum biomass was obtained in plants under 35 µM Fe and staircase treatment. Maximum chl a and b, chl a+b, carotenoids, root dry weight, flower diameter, flower longevity, number of flowers, and first flower fresh weight was observed in the plants under staircase treatment. Fe plays important role in biosynthetic pathway of chlorophyll and carotenoids. In addition, plants under staircase treatment showed the maximum photosynthesis and transpiration rate. Kong et al. (2014), reported that Fe deficiency led to decrease of δ- aminolevulinic acid and protochlorophyllide as precursors of chlorophyll. Ethylene and ABA are involved in Fe-deficiency signalling in plants, and these compounds may hasten senescence (Satoh, 2011). The short flower lifetime found in the present experiment in the low Fe treatment may be due to the boost in ethylene and ABA synthesis in response to Fe deficiency. On the other hand, plants under staircase regime had higher photosynthetic pigments that led to maximum photosynthesis. Increasing flower quality, quantity and longevity related to higher photosynthesis activity. Iron is a component of a number of proteins and enzymes, such as iron-sulfur (Fe-S) proteins and non-heme iron proteins, which are required during photosynthesis (Chakraborty et al., 2012). Li et al. (2016) investigated the influence and interaction of Cadmium (Cd) and Fe on photosynthesis and reported that Cd inhibits photosynthesis activity, but Fe alleviates the Cd-induced changes in photosynthesis activity. In addition, higher MDA contents were observed in plants under 35 µM Fe and staircase treatment. Li et al. (2012) reported that the high levels of Fe led to maximum MDA contents.
Conclusion: Growing the plants with staircase treatment increased flower yield, quality and longevity. These parameters are the most important factors in growing of ornamentals plants. Whereas Fe fertilizers are so expensive, restricting the use of expensive products such as Fe (III)-chelates at some growth stages can contribute to decrease the cultivation costs and minimize environmental pollution associated to an excess of fertilizer inputs. Therefore, gradually increasing Fe concentrations during production of Calendula officinalis under soilless culture would be recommended.
L. Shekari; M. M. Kamelmanesh; M. Mozafarian; F. Sadeghi
Abstract
Introduction: Aluminum (Al), cobalt (Co), sodium (Na), selenium (Se), and silicon (Si) are considered as beneficial elements for plants. They are not required for all plants but they can improve the growth and development of some plant species. Selenium is an essential element for human with antioxidant ...
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Introduction: Aluminum (Al), cobalt (Co), sodium (Na), selenium (Se), and silicon (Si) are considered as beneficial elements for plants. They are not required for all plants but they can improve the growth and development of some plant species. Selenium is an essential element for human with antioxidant and antivirus functions but is not considered essential for higher plants. Selenium is reported to be protective against cancer and more than 40 types of diseases are associated with Se deficiency. The amounts of selenium in food also depend on the amount of the element in the soil. However, its beneficial role in improving plant growth and stress tolerances is well established. Plants revealed different physiological reactions into the Se levels, some specious accumulate it unlike some which are sensitive and Se is a toxic element for them. Some studies showed that Se can reduce adverse effects of salinity, drought, high and low temperatures and also heavy metal stress by enhancing antioxidant defense and MG detoxification systems. Pepper is one of the most important vegetable crops which have strong antioxidant properties. The effect of Se on vegetable especially on hot pepper is not well documented.
Materials and Methods: Present experiment was designed in order to study the effects of different concentrations of selenium on vegetative growth and physiological trait of hot pepper (Capsicum annum cv. kenya) in hydroponic conditions in the greenhouse at the Department of Horticulture Science, Islamic Azad University of Shiraz (Iran) under natural light with a day/night average temperature of 25/17 °C, relative humidity of 50±8.5% and photoperiod 14/10 (day/night). This experiment was carried out based on completed randomized design (CRD) with 5 Se levels at (0 as control, 3, 5, 7 and 10 µM) with 3 replications. 30 days old seedling with uniform size were selected and transplanted into 4 L pot containing a mixture of peat moss and perlite (1:1). The nutrient solution was a modified Hoagland’s solution and each plant received 400 mL nutrient daily. Selenium concentrations were added by 0, 3, 7 µM Na2SeO3 (Merck, Germany) 10 days after transplanting. Leaf number (by counting), leaf area (with leaf area meter), relative water content (RWC), membrane stability index (MSI), chlorophyll and carotenoids content were determined one month after treatment applications. All data were subjected to one-way ANOVA by Statistix 8 (Tallahassee FL, USA) and the means were compared for significance by the least significant difference (LSD) test at p < 0.05.
Results and Discussion: The results showed that selenium supplement at 5 µM significantly increased relative water content by 12.8% compared to control. Se increased root growth and thus absorbed more water and increased RWC in present experiment. Selenium at 7 and 10 µM Se increased membrane stability index by 33.61 and 80.06, respectively, compared to control which may be due to increasing potassium by Se application. Selenium at 3 and 5 µM increased leaf area by 24.6% and 25.1% relation to plants which were grown without Se supplementation. Leaf number increased by application of 5 µM Se about 15.14% and chlorophyll a, b and total increased by 64.67%, 38.5% and, 55.8%, respectively, in comparison with plants grown without Se application. Carotenoid content was not affected by different Se concentrations. Se increase chlorophyll content by increasing Mg and Fe absorption, or protect of chlorophyll content against chloroplast enzymes. The highest leaf area was observed at 3 µM Se in comparison with other treatments. Se at 5 µM is beneficial for growth, photosynthesis pigments, and leaf area and leaf number. Se application had no beneficial influence on lateral shoot. The highest starch concentration was observed at 5 µM Se in comparison with other treatments and control (by about 60% in comparison with plants were grown without Se application).
Conclusion: In general, the result of present study indicated that selenium at low concentrations improved plant growth (such as leaf area and leaf number), physiological trait (relative water content and membrane stability index) and photosynthesis pigments (chlorophyll a and b) of hot pepper in hydroponic conditions. Also, it is suggested that this experiment should be repeated on some other important vegetable during growth and reproductive stages in hydroponic and soil condition and also on hot pepper quality and quantity of fruit.
