Plant Productions
Year:2019 | Volume:42 | Issue:1|Papers Count:10

Background and Objectives Calcium is a key plant nutrient with significant functions including reducing fruit senescence; calcium deficiency has been involved in several physiological disorders in fruits. Pre-harvest foliar application of calcium chloride (CaCl2) is an efficient and safe strategy to maintain or improve the fruit quality during storage. Also, calcium significantly increases the membrane and cell wall density and reduces the physiological disorders of the fruit. Thus, the aim of this study was to evaluate the effect of pre-harvest CaCl2 sprays of citrus trees at three fruit development stages on improving fruit quality and antioxidant capacity during storage. Materials and Methods To conduct this research, citrus trees of three different varieties (‘ Thomson’ , ‘ Moro’ and ‘ Page’ ) were sprayed with different concentrations of CaCl2 (0, 1, 2 and 4%) at three fruit development stages (120, 140 and 160 days after full bloom). After harvesting, citrus fruits were stored at 5° C and 85% relative humidity for 60 days. Then, weight loss and juice percentage, total carotenoids, superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity, and total antioxidant capacity (IC50 content) of the fruits peel and pulp were determined on 0 (harvesting time), 30 and 60 days. Data were analyzed using SAS (Ver. 9. 1) and significance of the differences between the means was computed using Tukey test. Results Results showed that weight loss percentage in fruit treated with CaCl2 (especially in 2 and 4% treatments) of all three cultivars was significantly less than control during storage. Total carotenoid of pulp of Thomson and Moro cultivars increased with increasing of CaCl2 concentrations compared to control during storage. In Page mandarin, the carotenoid content of pulp was not affected by calcium chloride treatment. Results also showed that SOD activity in peel and pulp of treated fruits was higher than control at harvest time. At the time of harvesting, the peel APX activity of Thomson and Moro cultivars (control) was higher than those treated by calcium. Antioxidant capacity (based on IC50 content) of peel and pulp varied depending on the cultivar and the treatment. That is, the highest antioxidant capacity was determined in ‘ Thomson’ at harvest time and in treated fruits with high level of CaCl2. Discussion In the present study, the CaCl2 pre-treatment was sprayed on the citrus trees and the results indicated that pre-harvest calcium chloride significantly decreases weight loss percentage and increases antioxidant capacity, SOD activity and total carotenoid contents in citrus fruits during storage. It seems that the accessibility of sufficient CaCl2 during plant growth has a strong influence on concentrations of bioactive compounds and overall antioxidant properties of citrus fruits. Overall, it is suggested that an appropriate CaCl2 pre-treatment of citrus tree can help improve or maintain pulp and peel quality during storage. It is further suggested, using chlorinefree calcium sources in southern Iran with alkaline soils.

Background and Objectives Olive (Olea europaea) is one of the most important fruit trees in the pomology industry of Iran. Statistics shows that this fruit tree is cultivated in more than of 102 thousand hectares of territory of Iran. Due to severe water shortages, it is necessary to make use of methods with objectives to reducing the negative effects of drought on plant and to increasing water use efficiency. Previous studies stated that plant growth regulators such as salicylic acid could apply to reducing the adverse effects of environmental stresses. Salicylic acid (SA) influences various physiological and biochemical functions in plants and has diverse effects on the tolerance to biotic and abiotic stress. The objective of this study was to investigate the effects of exogenous SA application on biochemical traits of ‘ Konservalia' olive leaf under 100 %, 66 % and 33 % ETcrop by analyzing chlorophyll content, total soluble carbohydrate and proline. Materials and Methods The study was conducted in order to investigate the effect of different levels of water deficit (100, 66 and 33 percent of evapotranspiration (ETcrop)) and four concentrations of salicylic acid (0, 0. 5, 1 and 2 mM) on fresh and dry root weight, stem and leaf and leaf number, leaf area, stem diameter, leaf proline, total soluble sugars, chlorophyll content as a factorial experiment based on a randomized complete block design with three replications. Two-year old olive trees (Olea europaea cv. ‘ Konservalia’ ) were used. Seventy-plants were grown in 11 L pots, containing a mixture of field soil (73. 2 % sand, 13. 3 % silt and 13. 5 % clay) and manure. Plants were sprayed with four concentrations of salicylic acid and irrigated every ten days, according to the amount of evatranspiration of plants (ETcrop). Parameters such as leaf proline and total soluble carbohydrates content, chlorophyll content were measured three times at intervals of once every 30 days after treatment. Data analysis was performed using MSTATC and SAS software and mean comparison was done by Duncan's multiple range test at 5 and 1 % probability Results The results showed that leaf proline and total soluble carbohydrates increased while chlorophyll content (chlorophyll a, b and total) decreased with increasing levels of water deficit. Results also showed that the interaction of salicylic acid and irrigation had a significant effect on fresh and dry root weight, stem and leaf, leaf area and plant height at p<0. 01. In the three level irrigation (100% ETc, 66% ETc and 33% ETc), the value of fresh and dry weight of root, stem and leaf, leaf area and plant height were higher in plants treated with salicylic acid compared with plants untreated with salicylic acid. In 66 and 33 % ETcrop treatments, amount of leaf proline and total soluble carbohydrate chlorophyll content (chlorophyll a, b and total) were obtained higher in plants sprayed with 2 mM SA compared with no-sprayed plants, but in 100 % ETcrop treatment, these indices were not different between sprays and no-sprayed plants with salicylic acid. Discussion In this study, the role of SA in plant tolerance to abiotic stresses such as heat, heavy metal, and osmotic stress was reported. The results showed that 2 mM SA application alleviated the adverse effects of drought stress (66 and 33 % ETcrop) in young olive trees through the improvement of chlorophyll content, enhancing leaf total soluble carbohydrate and proline content which can lead to osmotic adjustment.

Background and Objectives Rye (Secale cereale L. ) is one of the important and valuable Gramineae that is used for bread making and fed in some areas. Identifying correlation coefficients among the measured traits is very important and aids to evaluating the magnitude of interrelationships between how traits can facilitate the application of indirect selection in plant breeding programs. The target of this research was estimating the correlation coefficients, and path analysis among some important traits for selection criteria for improving grain yield in rye. Materials and Methods In order to evaluate the relationships between seed yield and its components, 64 different rye genotypes were evaluated in simple lattice design with two replications during 2016 in Maragheh region. Phenotypic correlation coefficients were calculated for ten characters during the growing season and the correlation coefficients between grain yield and different characters were subjected to path coefficient analysis separately for partitioning these values into direct and indirect effects. Stepwise regression technique was used to obtain the best fitted model as well as to estimate direct and indirect effects via path coefficient analysis. Applying bootstrap method verified the obtained results from conventional method. Results Correlation analysis showed that seed yield was associated significantly and positively with spike weight, weight of seeds per spike, harvest index of spike, seed number per spike, number of spike per area and harvest index traits. Using stepwise regression analysis, the share of the most important traits was determined and weight of seeds per spike and number of spike per area entered into regression model and explained 75 percent of the existing variation among genotypes. The results derived from path analysis indicated that, two above mentioned traits had significant effects on seed yield with 0. 71 and 0. 60 coefficients, respectively. On the other hand, Discussion In general, from this study we found that two traits including weight of seeds per spike and number of spike per area as the first order and related traits to spike, thousand seed weight, stem diameter, harvest index, awn length and plant height were in the second order for increasing seed yield and could be used as the selection indices for improving seed yield. Also, the used method for obtaining path coefficients was proved useful in analyzing correlation coefficients in breeding programs for evaluation of interrelated variables.

Background and Objectives Chrysanthemum, due to numerous applications in floriculture and medicinal industries has been considered one of the most important ornamental plants and medicinal plants in the global area. In addition to being used as a cut flower, it also has a special place among potted flowers and gardens. Also, it is used as a medicinal plant with strong healing properties in traditional Chinese medicine and considered to treat eye diseases, headaches, colds, and etc. However, only a few reports have been presented in the field of genetic diversity of Chrysanthemums by morphological and molecular markers. Therefore, there is a need for further identification of germplasm and cultivars of Chrysanthemums in Iran. This study aimed to assess the genetic diversity of 15 cultivars of Chrysanthemums based on morphological characteristics and selection of cultivar adapted to Khorramabad region. Materials and Methods This experiment was carried out in a randomized complete block design with three replications in the area of Beiran-Shahr, Lorestan province in 2017. Twenty-one morphological characteristics were determined from fresh materials. These traits in accordance with the given instructions describing World UPOV Chrysanthemums, were measured. Quantitative measurements were carried out on 10 leaves per cultivars. Some variables including diameter (branches, petioles, discs, buds and flowers) were measured by digital caliper. The traits such as length and width of leaf, plant height, length and width of the tab florets with ruler were measured. Results Based on data analysis most of the traits in cultivars showed significant differences (p≤ 0. 01). Results showed that the correlation between leaf area with leaf width, petiole diameter and number of leaves has a positive and significant correlation with the probability level of 5%. The most significant and negative correlation (r = 0. 99) was observed between number of flowers per plant and number of florets. Based on the results obtained from principal components analysis, seven independent and major components with Eigen values greater than one could explain 89 percent of the total variation. The first component, verified 24. 4 percent of the total variation. Cluster analysis of cultivars in Euclidean distance of 26. 68, was categorized into two main groups. The cultivars "Avadis" and "Norooz3" in the first group were distinguished from the rest of the cultivars with the lowest height. The "Fariba"; "Ashraf" and "Andiea" cultivars were placed in the group and most abundant cultivars. Discussion Based on the results, leaf size, plant height, number of branches and number of flowers in plant traits were most important in recognizing the diversity of cultivars Chrysanthemum. By using some cultivars belonging to the first cluster with less height and cultivars in the second cluster with more leaves and flowers as a parent, a new cycle of Chrysanthemum breeding program can be initiated.

Background and Objectives The nature and magnitude of gene action is an important factor in developing an effective breeding program. Combining ability analysis is useful in assessing the potential inbred lines and helps in identifying the nature of gene action involved in various quantitative characteristics. This information is helpful to plant breeders for formulating hybrid breeding programs. Therefore, the objectives of the present research were to determine combining ability, heritability and heterosis of tuber yield and some agronomic traits in potato using line × tester mating design. Materials and Methods In order to determine combining ability, heritability and heterosis of tuber yield and some agronomic traits in potato, three lines were crossed with two testers. Parents and their F1 progenies were arranged in randomized complete block design with three replications using line × tester (3 × 2) mating design. Results Analysis of variance showed significant differences among genotypes for all traits; thus line × tester analysis was performed. Among the lines, line L1 (Caeser) had significant positive GCA for tuber yield, tuber weight per plant, tuber number per plant, main stem number and plant height. Among the testers, tester T1 (Luca) showed significant positive GCA for tuber yield, tuber weight per plant, tuber number per plant and tuber dry matter. Among the hybrids, the hybrids (Satina × Luca) (T1 × L3) and (Caeser × Savalan) (T2 × L1) showed significant positive SCA effects for tuber yield, tuber weight per plant and tuber number per plant. The SCA variance was higher in magnitude than the GCA variance for all the characteristics and baker coefficient indicated the predominance of non-additive type of gene action for the expression of these characteristics. High general heritability and relatively low specific heritability were observed for all traits. Hybrid (Satina × Luca) had the highest heterosis for tuber yield. Discussion The importance of additive and non-additive genetic effects is well established in controlling many traits in potato. It was shown that the dominance effects of the genes played a major role in the variation of tuber yield in potato. Based on the results of the current study the SCA variance was higher in magnitude than the GCA variance for all the characteristics and baker coefficient indicated the predominance of non-additive type of gene action for the expression of these characteristics. Heterosis and combining ability is prerequisite for developing a good hybrid variety of potato. According to this research, the (Satina × Luca) cross had the highest heterosis for tuber yield and was recommended as the most promising combination for developing high yielding hybrid potato genotypes.

Background and Objectives Production of pure lines is one of the most important tools due to production of high-yield seeds. Pure lines can be produced in a short time using in vitro techniques and therefore, reduce several years in required time for conventional plant breeding programs. The purpose of this study was investigation of different concentrations of TDZ on production of haploid plants in cucumber ovule culture. Materials and Methods The experimental layout was conducted in factorial arrangement in randomized complete design with three replications in greenhouse and laboratory of Razi university during 2015-2017. Factors were two cucumber genotypes (Esfahani and Beit Alfa) and different concentrations of TDZ (0, 0. 01, 0. 02, 0. 03, 0. 04, 0. 05, 0. 06, 0. 07, 0. 08 mg/l). Unfertilized ovaries were harvested 1 day before an thesis and they were sliced into 1 mm cross sections under sterile conditions and placed on solid MS medium. Immediately after placing the unfertilized ovary slices of each genotype on induction medium, they were exposed to a thermal shock pretreatment at 35± 1° C for 3 days. The first visual structures formed after 3 days in culture. After two weeks of culture, the frequency of embryo formation was recorded. After embryogenesis, the embryos were sub-cultured in medium containing 1. 5 mg/L-1 GA3 and finally cultured in medium containing 0. 05 mg/L-1 NAA and 1. 5 -1 mg/L BAP for organogenesis. Results Results indicated a statistically significant effect at 1% among TDZ concentrations. Genotypes and interaction between genotype and TDZ concentration did not have a significant effect on embryo induction. According to the results of means comparison, M8 medium with the average of 23. 33 for Esfahani genotype and 20. 66 for Beta Alfa genotype had the highest embryo induction and M1 showed the lowest embryo induction for both genotypes. Ploidy level of calli and embryos were identified by Flucytometry assay. Haploid embryos were transferred to the regenerative medium. The chromosome content of haploid plants was doubled spontaneously in all regenerated plants. Double haploid plants originated from megaspore and they were equivalent to haploid, which relates to homozygosity and can be used directly in breeding program. Discussion The high number of embryos was obtained in high concentration of TDZ (0. 08 mg/l). Flucytometry assay is a way to recognizing ploidy level in plant tissues; thus it could be useful in choosing haploid tissue. Spontaneous chromosome doubling may occur via somatic cell fusion, endoreduplication, endomitosis and possibly many other mechanisms. In conclusion, the higher rates of embryo formation frequency achieved and doubled haploids obtained in the present study are promising for future work.

Background and Objectives Salinity is an important environmental tension limiting growth and productivity of plants worldwide. The harmful effects of high salinity on plants can be observed in senescence, necrosis of plant organs and decrease productivity. Major processes such as photosynthesis, protein synthesis, and energy and lipid metabolism affect plants during the beginning and development of salinity stress. Calendula officinalis L. belongs to the Asteraceae family; it is an annual with bright or yellow orange daisy-like flowers which are used for medicinal or culinary purposes. Organic fertilizers develop favorable physical, chemical and biological environment in the soil. They stimulate plant root growth, increase nutrient uptake and soil water-holding capacity, decrease evaporation from the soil and surface water runoff, facilitate drainage, regulate soil temperature and provide a rich substrate for soil microbes. Materials and Methods This study was conducted to determine the effects of soil salinity and organic amendments on some growth characteristics, absorption of nitrogen, phosphorus and potassium and peroxidase enzyme activity in pot marigold plant (Calendula officinalis L). In a factorial experiment and completely randomized design (CRD), five levels of organic amendments (control, 0. 5 and 1 g. L-1 algae extract, 20% v/v of pot volume cow manure and 20% v/v of pot volume vermicompost) and three levels of salinity (3. 5, 7. 5 and 10. 5 dS. m-1 ) with three replications per treatments were applied. In this experiment, media without organic amendment were considered as control. Results Results showed that increasing soil salinity levels progressively decreased the growth characteristics and nutrients uptake. The maximum leaf number, fresh and dry weight of flowers and nitrogen, phosphorus and potassium absorption were obtained in cow manure treatment and EC = 3. 5 dS. m-1, While the highest flower diameter was observed in sea algae treated plants (0. 5 g. l-1 ) in media with EC = 7. 5 dS. m-1. Salinity causes growth reduction due to the low osmotic potential of the medium and by a specific ion effect as a secondary cause in several vegetable crops. Discussion The results of the present study showed that the organic media can improve leaf number, crown diameter and fresh and dry weight of flowers. This can be due to increased media moisture storage and enhanced nutrient absorption. All treatments significantly increased growth characteristics of pot marigold compared to control. The positive effect of cow manure to nutrients uptake could be because of rich N, P, K compared to the others. According to the results, in normal conditions, pot marigold plant could tolerate salt stress until 7. 5 dS. m-1 but by suitable media culture its threshold tolerate will be increased up to 10. 5 dS. m-1. Also it was revealed that cow manure compared to other treatments could increase plant tolerate to salt stress and growth characteristics.

Background and Objectives Weeds are the most important factors in sugarcane yield loss. Successful weed control is essential for economical sugarcane production. Weeds can reduce suercane yields by competing for moisture, nutrients, and light during the growing season. Weed control is most critical early in the season prior to sugarcane canopy closure over the middle rows middles. Herbicides can be useful and economical tools in sugarcane production. Indaziflam is an alkylazine herbicide that is labeled for use in turf, for perennial crops and for nonagricultural situations for preemergent control of grasses and broad leaf weeds. The objective of this research was evaluation of the efficacy of indaziflam on control of Cynanchum acutum in sugarcane fields in Khouzestan, Iran. Materials and Methods The experiment was conducted in 2015 growing season in a sugarcane field Shoaeibiyeh, Shoushtar, Khouzestan, Iran. The trial was randomized in complete block design with four replications. Variety and type of culture were Cp69-102 and plant, respectively. Treatments were 1-indaziflam (75 g ai ha-1, as preemergence); 2-indaziflam (50 g ai ha-1 as preemergence); 3-Trifloxysulfuron sodium + ametryn -1 (1875 g ai ha, as postemergence); 4-2, 4-D+MCPA (1687. 5 g ai ha-1 ); 5-glyphosate + Ammonium sulfate 6-weeding and 7-weed infested. The herbicides were applied with backpack sprayer equipped with flooding and T-jet nozzles calibrated to deliver 300 L ha-1. Every two weeks, dry weight and density reduction percentage of Cynanchum acutum were measured and 90 days after herbicide applying, stem length, stem weight, the middle internode diameter and length of sugarcane and also purity, pol and recoverable sugar of sugarcane were determined. Statistical calculations were accomplished through the SAS 9. 2 software and graphs were drawn by the Excel software. Results However, indaziflam efficacy was reduced over time. Other herbicides such as indaziflam as 50 g ai ha-1 and trifloxysulfuron sodium + ametryn indicated a good effect in Cynanchum acutum control compared with 24-D + MCPA and glyphosate + Ammonium sulfate. Single stem weight (0. 72 kg), the middle internode diameter (1. 85 cm), number of internode (18. 2 cm) and cane yield (117. 90 t ha-1 ) were the greatest in indaziflam (75 g ai ha-1 ). The greatest brix (21. 48%), invert sugar (0. 533%), recoverable sugar (11. 26%) and the lowest fiber content (12. 61 t ha-1 ) were obtained in indaziflam treat (75 g ai ha-1 ). Discussion The present research indicated indaziflam could control Cynanchum acutum in sugarcane field although indaziflam efficacy was reduced over time. However, there were no adverse effects of indaziflam rates on sugarcane observed; therefore, this herbicide could be used in sugarcane fields. Since highly intensive use of herbicides in fields causes to herbicide resistance, herbicides with different mechanisms of action should be registered for weed control of sugarcane. Because of low volume of indaziflam as compared to current herbicide of sugarcane, this is a good candidate for application in sugarcane fields in rotation or mixture with other recommended herbicides.

Background and Objectives Squash is an annual herbaceous plant and grows in tropical and subtropical regions of Europe and America. Edible species are divided into three groups of zucchini or courgette, gourd and pumpkin squash. The seed of pumpkin squash has high nutritional value due to its high protein and oil content. Iran is ranked fourth in terms of production and cultivation area of squash in the world after China, India and Russia. The present study was conducted in order to determine the most important morphological and physiological characteristics influencing yield in squash landraces from Northwest of Iran. Materials and Methods Eighteen squash landraces comprising 11 confectionery landraces, 5 gourd landraces and 2 ornamental landraces were evaluated in a randomized complete block design with three replications in Saatlou research station of West Azerbaijan. The landraces were evaluated for morphological and physiological characteristics based on International Board for Plant Genetic Resources (IBPGR)) descriptor. Results The results of phenotypic correlations revealed that the characteristics including number of fruit, fruit weight, 100 seed weight, fruit diameter, seed thickness, plant height, internodes length, primary branch and fruit pH and characteristics including seed weight, peduncle lengths, sepal’ s length of female flower and fruit total soluble solids have positive and significant correlations with fruit yield at 1 and 5 percent probability level, respectively. In stepwise regression, four features including internodes length, sepal’ s length of female flower, chlorophyll percentage and fruit pH were entered in model. The results showed that fruit pH and internodes length have the most direct and positive effect on the fruit yield, and the percentage of chlorophyll has the highest indirect effect through internodes length on the fruit yield. Discussion Sequential path analysis showed that selection of genotypes based on only correlation coefficient may not be effective. Several characteristics were identified to explain squash yield during path analysis. Selection based on identified characters would be more effective in improving yield in squash breeding programs.

Background and Objectives Wheat is ihe most important crop in Khoozestan proviance. Under such a condition wheat experience drought stress in response to both low water resource limitaion and respiration. Detremination of tolerant trais, is one of the most important goals in wheat breeding programs under stress conditions. This research was carried-out to study the susceptibilty of some phenological stages of wheat genotypes based on grain yield and its components. Materials and Methods The research was conducted in split plot experiment using complete randomized block desgin with three replications, in 2010-11 and 2011-12 cropping seasons. The main plots included full irrgation as the check and irrigation withholding at tillering, stem elongation, heading and grain filling stages, and the sub plots consisted of four wheat genotypes. Days to some phenological stages, grain yield and yield components were measured. Planting seeds of each genotype was conducted based on 400 seeds per square meter in six planting lines with six meters in length and 20 cm spacing between lines. By monitoring the meteorological forecast, in case of probability of rainfall, for protection of the field from possible rain, a metal guard with 1. 2m height and covered with transparent polyethylene was used. Results The effect of year was not significant for any of the studied traits. The effect of irrigation stress treatment on grain yield and its components was significant. Except for biological yield and number of grain per spike, the differences between genotypes were significant for all traits, and the interaction of irrigation × genotype treatment for all traits studied in this study was significant. Results indicated that grain yield in normal irrigation was 4919 Kg/ha and in irrigation withholding at tillering, stem elongation, heading and grain filling growth stages were 4109, 4442, 3988 and 4455 Kg/ha respectivley. Heading stage was evalated as the highest susceptible, for biological yield, grain yield, haevest index, grain per spike and grain per unit area with succeptibilty indices of 1. 47, 1. 39, 1. 33, 4. 80 and 1. 75 respectivley. Discussion According to the results of this study, due to the more severe effect of drought stress on grain yield at spike emergence stage, irrigation is important at this stage. In the absence of irrigation at the mentioned stage, yield reduction will be higher than non-irrigation at other stages. Thus, based on succeptibilty index, compared to other stages, heading and grain filling stages were evaluated as the highest and lowest susceptible stages in response to water dificit respectivley.