فهرست مطالب seied mehdi miri

The genus Lepidium from the family Brassicaceae has 16 species in Iran, and the most famous species is garden cress (L. sativum), which is used as a vegetable or medicinal plant. The purpose of this study is to evaluate the quality and quantity of seed essential oil of seven L. sativum populations collected from different climatic regions of Iran. Seeds of L. sativum populations were hydro-distillated by clevenger, and the chemical composition of the essential oils and their quantitative percentages were identified using gas chromatography-mass spectrometer (GC-MS). The main compounds of seed essential oil were monoterpenes 1,8-cineole (44.5%), α-terpinyl acetate (13.9%) and α-pinene (7.7%). The populations of Karaj, Kerman and Qazvin had the highest amounts of 1,8-cineole, α-terpinyl acetate and α-pinene, respectively. The results of cluster analysis based on the chemical composition of garden cress seed essential oil using the Nearest neighbor method showed that seven studied populations were divided into two groups, and this grouping did not match the geographical coordinates of the regions. The first group included the populations of Kerman, Qazvin, Shahriar and Tabriz, and the second group were the populations of Shiraz, Hamadan and Karaj, which had the highest amount of 1,8-cineole and the lowest amount of α-terpinyl acetate and 7,10-hexadecadienoic acid, methyl ester. According to the results of the bi-plot diagram of principle component analysis (PCA), Karaj population -which had the lowest values of the first and second components- was placed in a distinct group. No significant correlation was observed between the main compositions of the essential oil with the geographic coordinates and weather conditions of the collection sites.

The genus Lepidium L. is one of the three large genera of the Brassicaceae family, which are used as vegetables or medicinal plants. Knowing the relationships and genetic diversity of Lepidium L. species by molecular markers is an ideal approach to improve and conserve of their germplasm.

The genetic diversity and relationships among 22 populations belonging to three species of L. sativum, L. draba and L. latifolium using combined data of SSR, ISSR and SCoT markers based on analysis of molecular variance, indices of genetic diversity, cluster analysis, principal coordinates analysis and genetic structure were investigated.

Analysis of molecular variance showed that the genetic diversity within the groups is more than between the groups. The highest and lowest genetic diversity was related to L. sativum and L. latifolium, respectively. The highest Nei genetic similarity matrix was observed between L. draba and L. latifolium and the lowest similarity between L. sativum and L. latifolium. Neighbor-Joining cluster analysis divided the Lepidium populations into three groups and there was a weak separation between the species, which was confirmed by principal coordinate’s analysis and genetic structure, and it seems to be due to the gene flow among the populations of different Lepidium species and the existence of a common gene pool between them.

The results showed that the populations of the three studied Lepidium species have a high level of genetic diversity and gene flow, which can be used as valuable genetic resources in breeding programs.

The occurrence of inter-specific hybrids between two species in nature has the potential ability to develop new fruit trees with desirable traits. In this study, flower morphology, viability, and in vitro germination of pollen grains and self-(in) compatibility, using fruit set (%) and fluorescence microscopy methods were examined in three promising natural Prunus interspecific hybrids [P. armeniaca × P. salicina (Bavanat) and P. cerasifera × P. armeniaca (Shiraz and Shahriar)]. Bavanat and Shiraz had the highest flower diameter, while the highest number and length of stamens, as well as stamen number/pistil length ratio, belonged to Shahriar. The highest and lowest pollen viability and in vitro germination were observed in Shahriar and Bavanat, respectively. In general, sucrose concentrations of 150 to 250 g/l increased in vitro pollen germination rate, although concentrations of more than 150 g/l had a negative effect on Bavanat. The three-year average (2018-2020) of final fruit set by self-pollination ranged from 0% in Shiraz to 1.3% in Shahriar. A strong positive correlation was found between the occurrence of twin pistils and the mean temperature from July-August in the previous year. According to field self-pollination and fluorescent microscopy, all three genotypes were considered self-incompatible and needed pollinizer varieties.

Garden cress (Lepidium sativum L.) is anannual herbaceous species native to Egypt and south west Asia. The leaves of L. sativum possesse various medicinal properties. This study was conducted to evaluate the diversity of phytochemical constituents of seven populations of L. Sativum from Iran.

Experimental: 

The crude extracts of L. sativum populations leaves were obtained with methanol and were evaluated for the total phenol content, total flavonoid content, antioxidant activity using DPPH radical scavenging assay, and phenolic compounds by HPLC analysis.

The total phenolic content ranged from 1.25 to 2.36 mg GAE/g extract and the total flavonoid content was 0.74- 1.61 mg QE/g extract. Chlorogenic acid was the most abundant phenolic acid, followed by ferulic and caffeic acids. The content of kaempferol flavonoid was also 5.2-fold of quercetin. Leaf extracts of Tabriz and Kerman populations exhibited higher yields of phenolic constituents and antioxidant activity. The total phenolic content was positively correlated to total flavonoid content and phenolic acids (except caffeic acid) and negatively correlated to DPPH free radical scavenging activity (IC50). A negative correlation was found among total flavonoid content, caffeic acid, p-coumaric acid and ferulic acid with precipitation and relative humidity.

Recommended applications/industries: 

Our research is the first report to study the phytochemical profiles and antioxidant activity in different Iranian populations of L. sativum leaves for their health benefit.

Plum and prune are important temperate fruits, which have wide varieties of sizes and colors prized both for its exquisite fresh fruit flavor and in the fruitprocessing industry. Their fruits are rich source of minerals, vitamins, sugars and organic acids in addition to antioxidants. This research was conducted to evaluate the morphological and pomological characteristics of four cultivars of Japanese plum (P. salicina Lindl.) and prune (P. cerasifera Ehrh.) during 2020 in Karaj. According to the UPOV (International Union for the Protection of New Varieties of Plants) description, trees of Shablon had a semi-upright growth habit and Shiro, Mariana Inra and Seif-e-Dirras cultivars had an upright growth habit. The fruit of Shablon was also oblate and the other three cultivars were circular. The over color of fruit skin varied from yellow-orange (Shiro) to red (Seif-e-Dirras) and the color of fruit flesh was yellow (Shiro and Shablon) or orange (Mariana Inra and Seif-e-Dirras). Pomological results showed that Shiro and Mariana Inra had the highest and lowest yield (39.8 and 18.6 kg/tree) and number of fruits (1617.9 and 598.4 fruits/tree), respectively. Shablon and Mariana Inra had the highest fruit weight (32.2 and 31.0 g, respectively) and Mariana Inra had the longest fruit length (37.1 mm), while the lowest values of these traits were related to Seife- Dirras. The highest and lowest total soluble solids (TSS) were also obtained with Seif-e-Dirras (17.9) and Shiro (14.1). Tree yield had a positive correlation with the number of fruits/tree and total acidity (TA) and a significant negative correlation with total soluble solids and taste index (TSS/TA). Fruit weight and length also showed a positive correlation with leaf dimensions and a significant negative correlation with the number of fruits/tree and total soluble solids. In general, each of the cultivars are different from each other in terms of some characteristics and can be used for fresh consumption (Mariana Inra), juicing (Shiro) or drying (Seif-e- Dirras).

The morpho-phytochemical responses of purple coneflower (Echinacea purpurea (L.) Moench) to foliar application of salicylic acid (SA) and citric acid (CA) at 0, 1, 5 and 10 mM (in four-leaves stage and two weeks later) were determined in a field experiment. The results indicated that elevated levels of SA and CA induce plant growth and biomass, including plant height, number of branches, leaves and flowers, fresh and dry weight of aerial parts and SPAD value. The highest flower number, flower yield/plant, shoot fresh and dry weight were obtained by 10 mM SA combined with 5 or 10 mM CA. DPPH radical scavenging activity increased about 1.9 fold with 5 or 10 mM SA combined with 10 mM CA. HPLC analysis revealed that SA and CA enhanced phenolic acids (cynaric acid, chichoric acid, echinacoside, chlorogenic acid and caftaric acid) production in plants. There was a significant positive correlation between number and yield of flowers with all morpho-phytochemical attributes except root weight. The data suggested that combination of SA and CA especially at 5 and 10 mM may have higher capacity to improve morpho-physiological traits and phenolic contents of E. purpurea.

Lepidium L. is one of the important genera of Brassicaceae family, which is mostly distributed in Central, Middle and Southwest Asia, and some of its species are used as medicinal plants or vegetables. The study of genetic diversity using molecular markers plays a very important role in breeding programs and preservation of genetic resources. In this regard, comparison of different molecular markers in diversity variation is very important. In the present research, inter- and intra-specific genetic relationships of Lepidium spp. populations were evaluated using SSR (simple sequence repeats), ISSR (inter simple sequence repeats) and SCoT (start codon targeted) molecular markers. Analysis of molecular variance (AMOVA) revealed much higher variance within species than among species in all three markers. The highest intra-specific variance ( ) was obtained by SCoT markers. The results of genetic similarity matrix generated by SSR, ISSR and SCoT markers by Mantel’s test showed that the correlation between SSR and ISSR was highest (r = ), followed by ISSR and SCoT (r = ), then by SSR and SCoT (r = ) According to Nei’s genetic distance among the populations of Lepidium spp., the highest similarity (r = ) was found between Tabas (L. latifolium) and fsuhK (L. draba) using SSR markers; Khatam and Mehriz (L. latifolium), Tabas (L. latifolium) and hehsihsas (L. draba), Tabas (L. latifolium) and fsuhK (L. draba), Nir and Saveh (L. draba), Isfahan and Arak (L. sativum), Tehran and nevziQ (L. sativum) using ISSR markers; and Khatam and Mehriz (L. latifolium) as well as Nir and Saveh (L. draba) using SCoT markers. Based on the genetic distances between the populations, we can use cross between hehsihsas (L. draba) with Mashhad (L. sativum), Tabas (L. latifolium) and fsuhK (L. draba) with Tehran and nevziQ (L. sativum), and hehsihsas (L. draba) with Arak (L. sativum) to obtain the highest amount of heterosis in future breeding programs. Overall, the results indicated the usefulness of these three markers to estimate genetic distance among Lepidium L. populations.

Creating new efficient technologies such as doubled haploids is a fast solution for producing inbred lines. In this study, using the microspore embryogenesis method, doubled haploid (inbred) pepper lines were produced. The Topcross test was performed using 32 doubled-haploid lines produced and the topcross parent of California Wonder to examine the general combining ability of the lines. Hybrids derived from crosses line × tester in 2018- 2019 were planted. In order to evaluate the general combining ability of the lines, days to germination, days to flowering, days to fruit set, fresh fruit weight, dry fruit weight, fruit length, fruit width, thickness of fruit diameter, number of seeds, average yield per plant, number of fruits per plant and plant height were measured and analyzed. Comparison of means by Duncan test showed that top-cross progeny of DH55, DH64, DH57, DH53, DH217, DH202, and DH90 doubled haploid lines respectively with average of 8.58, 7.22, 7.18, 5.99, 5.93, 5.80 and 5.69 kg per plant had the highest fruit yield, among them the highest amount was related to the Topcross offset from DH55× California Wonder with an average of 8.58 kg per plant. The heritability of the evaluated traits was over 70%, among them the number of days to germination and the average fruit yield per plant were the highest. The above-mentioned lines also had the highest positive and significant general combining ability for the average yield per plant. Therefore, these 7 lines can be used as superior parent lines in future breeding programs.

Comprehensive information on the genetics basis of inheritance is important for breeding programs. Therefore, the present study was performed as a diallel cross using nine selected early maturity maize lines. Thirty-six hybrids resulting from their one-way diallel crosses were planted during the two crop years of 2020 and 2021 in a randomized complete block design with three replications. Based on a two-year combined analysis of variance, a significant difference was observed in the probability levels of one and five percent between the crosses for all studied traits. Diallel analysis by the fourth Griffing method showed that genes with additive and non-additive effects are involved in inheriting control of grain yield, plant height and ear height, but only genes with additive effects play a role in inheriting the traits of 1000-seed weight, grain moisture percentage and cob percentage. According to Baker ratio, the additive effect of genes has a greater role in controlling 1000-seed weight, cob percentage, plant height, grain moisture percentage, ear height and grain yield, because they explained high values of this ratio. The most desirable general combinator ability for grain yield were NK79 and KE 77008/1. Specific combining ability of grain yield of crosses KE 77005/2 × K 1263/1 and KE 76009/311 × K 1264 / 5-1 positive and significant was estimated. According to the results obtained for general and specific combining ability, the use of these lines and crosses in grain yield breeding programs will be promising.

This study was undertaken to investigate the effects of pruning and girdling on yield, fruit size and quality of ‘Kinnow’ mandarin (Citrus reticulate Blanco) trees during two seasons.  Research

The treatments included: control (unpruned and ungirdled trees), light pruning (removal 10% of 15-20 cm branches), intense pruning (removal 20% of 15-20 cm branches), girdling (removal 5 mm trunk bark), light pruning + girdling, and intense pruning + girdling. The treatments were applied in on-years (2016 and 2018) and traits were measured in following season.

Light pruning increased yield and fruit number by 170.4% and 191.5%, respectively, while fruit weight and volume slightly decreased by 7.2% and 12.4%%, respectively, compared to control. Fruit dimensions and, TSS and TA of fruit juice were not affected by treatments. However, TSS/TA ratio was significantly declined in both pruning treatments. In addition, vitamin C content of fruits decreased in pruned trees and light pruned + girdled trees compare to control. The yield was positively correlated with fruit number and negatively with fruit weight, fruit volume and vitamin C content.

 Despite these findings, more research is needed to identify mechanisms of pruning and girdling on alternative bearing in citrus.

These results suggested that pruning alone or plus girdling of ‘Kinnow’ mandarin trees reduce competition for nutrients and induce accumulation of carbohydrates in branches, which enhanced yield of the next season.

Somatic chromosome numbers and karyotypes of five populations of Nerium oleander in Iran were determined. karyological studies showed that, all the studied populations were diploid (2n = 2x = 22). The present study is the first report of the karyotype characteristics of N. oleander. The highest values of mean chromosome length (1.45 µm) and haploid chromosome length (15.9 µm) were found in the Chabahar population. The general shape of the karyotypes, indicated symmetry for all populations, as all chromosomes were metacentric type. According to Stebbin’s classification (1971), populations fall in class 1A, thus indicating occurrence of chromosome symmetry among the populations. In addition, a detailed account of karyomorphology and estimates of asymmetry indices showed that, all of the populations were symmetric, among which Khash and Kuhdasht populations were considered as the most asymmetrical and symmetrical karyotypes, respectively. Based on karyotypic parameters, the considered populations were categorized into two groups viz. Chabahar, Fanuj, and Khash populations which were previously reported as N. indicum in Flora Iranica, separated from Karaj and Kuhdasht populations.

Most almond cultivars grown in Iran exhibit gametophytic self-incompatibility. Therefore, they need to be pollinated by cross-compatible cultivars that bloom in the same time to produce commercial crop. One of the new almond genotypes is Karaj 33, which has very late flowering, high productivity, paper shell, high percentage of kernel to fruit, no double and twin kernel, and self-incompatible.

In order to select the suitable pollinizer for ‘Karaj 33’, an experiment was conducted using fruit set under field conditions and fluorescence microscopy methods, in which Tuono, Shekofeh and H were evaluated as pollen donors.

All almond cultivars/genotypes had high (80-85%) pollen germination. Tuono and H bloomed earlier (from 24th to 29th March), whereas Shekofeh and then Karaj 33 bloomed later (from 26th March to 1st April and 30th March to 3rd April, respectively). Cross-compatibility was confirmed in all the three cultivars/genotype by both methods. Shekofeh had almost overlapping flowering time with Karaj 33. The penetration rate of Shekofeh pollen tube was faster so that 96 h after cross-pollination, it reached the base of Karaj 33 style, while the other two reached 120 h later. The highest final fruit set was observed with the cross of Karaj 33 × Shekofeh.

 No limitations were found. Originality/Value: we can consider Shekofeh as a suitable pollinizer for Karaj 33.

Citrus is one of the most important fruit crops known by human. They are mainly grown in humid and arid subtropical regions. Citrus fruit undergo physico-chemical changes such as shrinkage, weight loss, decay as well as decrease in vitamin C during storage, which directly affects on fruits quality. Pre-harvest foliar application of salicylic acid (SA) is an efficient and safe technique to maintain fruit quality during storage. This study was carried out to evaluate the pre-harvest spray of SA (0, 1, 3 and 5 mM) on improving the shelf life and fruit quality of mandarin (Citrus reticulata L. ‘Pearl Tangelo’). The fruits were stored for one month at common storage (12±2˚C) and refrigerator (4±1˚C) and factors included peel moisture (%), fruit peel, juice and pulp weight (%), pH, TSS, TA, TSS/TA and vitamin C evaluated every week. The results showed that salicylic acid played a major role in increasing of fruit storage life. The highest percentage of peel moisture in both temperature conditions was observed with 5 mM salicylic acid. Low concentration of SA significantly preserved vitamin C, as the highest amount of vitamin C (64 mg per 100 ml of juice) were belonged to 1 mM salicylic acid at both common and cold storages. The lowest TSS/TA (9.2) was obtained with untreated SA-fruits in the common storage. The peel moisture (%), vitamin C and TSS/TA decreased during storage. The pH of fruit juice increased slightly in the second to fourth week of storage compared to the first week. There is a negative correlation between fruit juice weight (%) with TSS and TSS/TA. Since salicylic acid treatments are easy to set up and inexpensive, pre-harvest foliar application of SA could be a useful strategy to maintain physico-chemical and sensory quality parameters of mandarin fruit and prolong the storability of fruits during storage.

The somatic chromosome numbers and karyotype features of seven populations representing three species of Stachys L. (Lamiaceae), which are naturally distributed across Iran, were described. The results confirm the presence of different basic chromosome numbers including x = 15 and 17 within the genus. All the studied taxa were diploid and the chromosome counts of two species including S. benthamiana and S. setifera (2n = 34) are reported for the first time, while the chromosome number of S. byzantina (2n = 30) is confirmed. The chromosomes in the studied taxa of Stachys were generally small, as the longest chromosome length was detected on S. setifera (18713) (2.26 μm), whereas S. setifera (23354) demonstrated the shortest length (1.46 μm). The karyotypes were symmetrical composing of metacentric chromosomes as indicated by their mean arm ratio (AR) that ranged between 1.11 in S. setifera (23354) and 1.29 in S. byzantina (37985), so it was classified as class 1A according to Stebbins’ categories. Based on the values of total form percentage (TF%, 47.1%), Arano index of karyotype asymmetry (AsK%, 52.5%), symmetry index (S%, 94.0%) and differences of range relative length (DRL, 0.36), S. setifera (23354) had the most inter-and intra-chromosomal symmetric karyotype. Also, S. byzantina (37985) had the most inter-and intra-chromosomal asymmetric karyotype based on the values of TF% (42.0%), AsK% (56.1%), and relative length of chromosome (RL%, 6.6%). The results of cluster analysis based on chromosomal parameters divided the taxa into two main groups using the Ward method. Group I included taxa with x = 17 and group II contained S. byzantina (x = 15).

Lepidium spp. (Brassicaceae) are herbaceous plants grown worldwide and considered as vegetable, phytofood or medicinal plants. The genetic variation and genetic structure of 22 Lepidium (L.) accessions representing 3 species (L. sativum, L. draba and L. latifolium) from Iran were assessed using 14 Start Codon Targeted (SCoT) markers. A high polymorphism (98.4%), polymorphic information content (0.35) and polymorphic bands (4.5) indicated that SCoT markers are reliable for genetic variation analysis in Lepidium spp. Mean values of resolving power (Rp), marker index (MI) and effective multiplex ratio (EMR) were 5.0, 1.6 and 4.4, respectively. The highest percentage of polymorphic loci (92.2%), Nei’s gene diversity (0.35) and Shannon index (0.51) were observed in L. sativum. According to analysis of molecular variance (AMOVA), genetic variation within species was higher than between species. The highest similarity was found between L. draba and L. latifolium (r=0.94). A high level of gene flow was estimated in accessions of Lepidium species (Nm=2.65), which is further confirmed by neighbor-joining (NJ) cluster analysis, principal coordinates analysis (PCoA) and STRUCTURE analysis, that could reveal a poor separation between Lepidium species. NJ cluster analysis divided the Lepidium accessions into three groups, and the grouping of accessions was generally consistent with their origins. This study is the first to explore and prove SCoT markers suitability in genetic diversity of Lepidium spp. The genetic analysis information provided here would be helpful for breeding programs and germplasm conservation in Lepidium species.

Attractive and colorful cultivars of cactus have been developed that are mainly propagated by grafting. The aim of this study was to determine histological events during graft union formation in Gymnocalycium cactus influenced by BA (Benzyladenine) application, grafting method and rootstock. The basal end of the scions and the top end of the rootstocks were first dipped into BA solution at concentrations of 0, 100 and 500 mg L-1 for 10 s, before being grafted on Lemaireocereus marginatus and Myrtillocactus geometrizans rootstocks using horizontal or wedge techniques. Longitudinal sections of the graft union were taken weekly to observe the developmental process of graft formation. The rootstocks did not have a significant effect on grafting success and scion growth, while horizontally grafted Gymnocalycium showed better grafting success rate. The grafting rate and scion growth were enhanced by application of BA compared with the control. The best results were obtained from treating the graft cut-surfaces of both scions and rootstocks with 100 mg L-1 BA. Histological observations showed that the graft union process involved development of a thin necrotic layer, callus formation at the graft interface, cambium differentiation and initiation of new vascular elements, developing the new vascular tissue, and connection of scion and rootstock vascular bundles. BA stimulated rapid proliferation of callus between the scion and rootstock as well as differentiation of vascular elements. We suggest the horizontal graft and application of BA (100 mg L-1) on the cut surfaces of both scion and rootstock as an easy and reliable method for successful graft union in Gymnocalycium cactus, which may have potential use in the commercial production of other cactus species as well.

Due to the calcareous and high pH of the soil in most pistachio growing areas of Iran, the absorption of some elements such as iron and zinc from the soil by pistachio trees is difficult. Under these conditions, foliar application of nutrients is a better way to supply nutrients to deficient plants than to soil application. For this purpose, the efficiency of foliar application of different sources of iron along with zinc sulfate on the quantitative and qualitative characteristics of pistachio ‘Ahmad Aghaei’ was investigated in a completely randomized design with three replications. The experiment was carried out on 8-years old pistachio trees (cv. Ahmad Aghaei), which had been grafted on Fandoghi rootstock, at a commercial orchard in Pakdasht, Iran. Iron citrate (0.2 and 0.4%), iron sulfate (0.2 and 0.4%) or iron chelate (0.1 and 0.2%) in combination with zinc sulfate (0.1 and 0.2%) was carried out in early June and early July (at the filling stage). Pistachio fruits were picked up during the commercial harvest period, when the fruit reached a physiological maturity stage signalled by a reddish hull. The results of analysis of variance revealed that the effect of treatments on all studied traits was significant. The highest splitting rate (%) was obtained by iron citrate 0.4% + zinc sulfate 0.2%. The results of the Pearson correlation coefficients among the traits showed that there is a negative correlation between splitting rate (%) with small nut (%) and blankness (%) as well as a positive correlation with dry weight of 100 nuts, which shows that weight of nuts is the main cause of splitting rate. Foliar application of different sources of iron in combination with zinc sulfate led to a significant reduction in small nut (%) and blankness (%) so that the highest these two traits were related to control 1 (distilled water) and control 2 (common fertilization in the region). The fresh weight of 100 nuts from 140 g in control 1 reached to highest level (162.3 g) in iron citrate 0.4% + zincn sulfate 0.2%. The highest dry weight of 100 nuts was also related to this treatment. Foliar application of different sources of iron with zinc did not significantly increase total chlorophyll compared to controls. According to this study, in pistachio orchard with sandy loam soil in Pakdasht region, spraying of trees with different sources of iron (especially iron citrate) in combination with zinc sulfate could improve the qualitative and quantitative characteristics of pistachio.

Karyomorphological study was carried out on 11 accessions from 6 sections belonging to 7 species of Astragalus growing in Iran. Chromosome numbers and karyotypes of two species (A. cephalanthus DC. and A. jacobsii Podlech) are new records. Two ploidy levels 2n = 2x = 16 and 2n = 4x = 32 were determined, the chromosomes size varied from 2.51 in A. cyclophyllos to 3.79 μm in A. fasciculifolius Boiss. in two accessions of A. cyclophyllos , a single pair satellite chromosomes were observed.

Micropropagation of GF677 rootstock, the most widely clonal rootstock used in peach orchards, is an important method for large-scale production of disease-free plants. In this research, effects of media, plant growth regulators and carbohydrates in order to optimize the efficient micropropagation protocol of GF677 rootstock has been investigated.

In vitro shoots were multiplicated on MS, WPM and DKW media supplemented with 0, 0.5, 1, 2 mg L-1 BA. Proliferated shoots were rooted on MS, WPM and DKW media containing 0, 0.5, 1, 2 mg L-1 IBA. In another experiment, the effect of carbohydrate type was investigated.

High shoot number and node number as well as shoot fresh weight were achieved with shoot tips when cultured on MS medium supplemented with 1 or 2 mg L-1 BA. The highest percentage of rooted shoots was obtained on MS or WPM media supplemented with 1 or 2 mg L-1 IBA. Maximum root number was regenerated on WPM medium containing 1 mg L-1 IBA. Sorbitol was found to be more effective carbon source on shoot multiplication than sucrose, while the highest average of root number and root length were observed in the medium containing sorbitol and sucrose medium, respectively. Survival rate during the acclimatization in the greenhouse was 67%.

Limitations:

 Plant acclimatization needs to be studied for commercial production.

Originality/Value: 

This protocol has proven useful for micropropagation of GF677 rootstock.

Polyploids are organisms that have more than two paired homologous sets of chromosomes. Polyploidy has played a significant role in the evolution and diversification of higher plants. Artificial polyploidization has been induced using a few antimitotic chemicals such as colchicine, trifluralin and oryzalin. The type of mitotic inhibitors and their concentration and duration time are variable and species dependent. This technique can be applied ex vitro or in vitro, which tissue culture is simpler and more efficient. Changes in nuclear DNA content, gene expression and developmental processes due to ploidy manipulation can lead to morphological, anatomical and physiological changes in polyploid plants. In general, polyploid plants exhibit larger organs, greater biomass, higher yield, superior tolerance to biotic and abiotic stresses as well as higher primary and secondary metabolites. Also, polyploidy often reduce the fertility and allows the production of seedless fruits. In ornamental plants, increasing the size of polyploid flowers is aesthetically and economically important. There are two direct and indirect methods for ploidy determination of plants. Indirect methods are simpler but more inaccurate, involving the relationship between ploidy level with morphological (i.e. plant height, leaf size, and pollen diameter) and anatomical (i.e. stomatal frequency and size as well as chloroplast number in guard cells) properties. In contrast, direct assay methods, such as chromosome counting in mitotic cells of root-tips and flow cytometry are accurate techniques for the determination of ploidy level in plants. Overall, polyploidy manipulation has long been used in the improving yields of many crop plants and can be considered as one of the most promising tools in plant breeding programs.

Strawberry cultivation requires the use of cultivars adapted to the field or greenhouse conditions of the production region. Seven commercial of short day (SD) and day neutral (DN) strawberry cultivars (Camarosa, Kurdistan, Mrak, Paros, Queen Elisa, Selva, Ventana) were compared as a completely randomized design for different morpho-physiological characters under greenhouse conditions. The cultivars showed variation for all of the studied traits. Days to flowering varied from 53.2 to 94.5 days among the cultivars and Paros followed by Camarosa required minimum days for flowering. The highest total chlorophyll content and fruit volume were obtained in Camarosa and Paros, while the highest fruit weight was found in Paros, Ventana, Camarosa and Kurdistan. The cultivar Camarosa produced the highest of flower number (42.0), fruit number (36.3), fruit firmness (4.8 N) and yield (424.7 g per plant). The TSS/TA ratio was observed maximum in Paros and minimum in Ventana and Mrak. The highest of fruit anthocyanin was recorded in Camarosa and Selva. Correlation analysis revealed that yield per plant had a positive correlation with total chlorophyll content of leaves, number of flower and fruit, weight and volume of fruit, while negatively correlated to leaf area and crown number. According to stepwise multiple regression analysis, yield had the highest relationship with the number of flowers and fruit weight, respectively. Generally, vegetative traits as well as days to flowering and fruiting were higher in DN cultivars (Mrak, Selva). However, SD cultivars produced higher flower number, fruit size and yield than DN cultivars. The cultivars Camarosa and Paros were most adapted to the greenhouse conditions among the experimental cultivars.

The karyotypes of 10 species (15 accessions) of Allium from Iran were investigated using the squash technique and 1% (w/v) aceto-iron-hematoxylin stain. The basic chromosome number was x = 8, and only in A. giganteum (1) x = 7. Karyotypes of 14 taxa of Allium were diploid with 2n = 16; only A. macrochaetum was tetraploid with 2n = 32. Satellite chromosomes were seen in A. asarense. All karyotypes were symmetrical, consisting of metacentric and submetacentric chromosome pairs. Only A. caspium and A. stipitatum (1) had subtelocentric chromosomes. Karyotype analysis according to Stebbins categories placed the studied taxa in symmetric classes of 1A and 2A, indicating a symmetric karyotype. The results of the analysis of variance showed significant differences for total chromosome length (TCL), mean chromosome length (CL), long arm length (LA), short arm length (SA) and intrachromosomal asymmetry index (A1). The longest chromosome length was detected on A. asarense, A. elburzense, A. giganteum (3), A. rotundum and A. stipitatum (3) (17.9-19.7 μm), while A. ampeloperasum demonstrated the shortest value (8.2 μm). Results of cluster analysis based on chromosomal parameters classified the taxa into four groups using the unweighted pair group method with arithmetic mean (UPGMA). Using principal component analysis, the first three components determined 97.3% of the total variation. The grouping of the taxa based on the 2-D scatter plot using the first two principal components, corresponding to the results of the karyotypic characteristics.

In the current investigation, karyotype analysis and chromosome characteristics of six populations of Calendula officinalis L.(pot marigold) from Iran are studied. Results showed that all populations were diploid (2n= 2x= 32), and had symmetrical karyotypes composing mainly of metacentric and submetacentric chromosomes. The mean chromosome length ranged from 1.05 in Karaj to 1.50 μm in Masjed Soleyman 1. Haploid genome length was in the range of 16.89 to 24.07 μm and mean centromeric index (CI) of complements varied from 0.38 to 0.44, indicating the role of the quantitative genomic changes in the diversification of C. officinalis populations. Cluster analysis using chromosomal parameters and based on the UPGMA method classified studied populations into three major groups. In addition, the principal component analysis revealed the first two components account for 99.8% of the total variance. The results of the present study revealed the natural variation in six populations of C. officinalis, which can further serve conservation and breeding planning.

Paulownia tomentosa is very adaptable, widely distributed andextremely fast growing deciduous. The application of micropropagationtechniques in agro-forestry was essential because it offers a rapid wayof producing genetically uniform cloned stock with high quality. In order to study the effect of basal culture medium and growth regulatorson micropropagation of P. tomentosa, a factorial experiment wasconducted in a completely randomized design with four replications.The seeds were surface disinfected in a solution of 1.5% NaOCl for 10min and culture on MS medium containing 50 mg/l GA3. For shootmultiplication, isolated 1 cm long epicotyls were put on MS and DKWmedia supplemented with0.5, 1, 2 and 3 mg/l benzyl adenine (BA), 0.1mg/l NAA, 30 g/l sucrose, 7 g/l agar and pH = 5.6-5.8 beforeautoclaving. The subculture period was 4 weeks in growth chamberswith permanent temperature 25±1°C, white fluorescent light withintensity 3000 lx and 16:8 h photoperiod. Basal modified MS andDKW media (reduction of all macro elements by half) enriched with0.5, 1 and 2 mg/l indole butyric acid (IBA), 20 g/l sucrose and 7 g/lagar were studied for rooting efficiency. According to the results ofanalysis of variance, no significant differences were observed betweenMS and DKW media for multiplication and rooting traits. Due to thecompatibility of this species to environmental conditions, it seems thatthe same behavior was observed in tissue culture and showed the samereaction in both MS and DKW media for all traits. Mean comparison results showed that the highest shoot number (1.8-2.1 shoot perexplant) and shoot fresh weight (1.5-1.7 g) were obtained in mediacontaining 2 or 3 mg/l BA. The highest rooting percentage (100%), rootnumber (0.8 root per explant), mean root length (4.5 cm) and plantletfresh weight (2.9 g) were obtained in media enriched with 2 mg/l IBA.Rooted plantlets were rinsed with tap water to remove the mediumfrom the roots and transferred to the substrate of peat moss : cocopeat:perlite (2 : 2 : 1), treated with Mancozeb fungicide (0.2%) andcultivated for 30-40 days in growth chambers with gradual decrease ofthe atmospheric humidity. There is a significant positive correlationbetween root number as well as plantlet fresh and dry weight withex vitrosurvival. Acclimatization results showed that 90% of plantletssuccessfully survived after four months. The method described here canbe successfully employed for large scalein vitropropagation ofP. tomentosa plants.

Stress caused by abiotic factors, such as salinity, decreases production of bananas, because it is very sensitive to salinity. This study aimed to investigate the effect of gamma (γ) ray-induced in vitro mutagenesis as well as in vitro and ex vitro reaction to salt stress (NaCl) in banana (Musa AAA cv. ‘Dwarf Cavendish’). Shoot tips of banana were irradiated with gamma rays at doses of 25, 35 and 45 Gy, and subjected to MS medium containing additional NaCl (0, 100, 120, 140 and 160 mM) for two months (1st salinity stress) as factorial based on completely randomized design with five replications.The surviving shoots were transferred to a salt-free MS medium for one month, and then the salinity stress, as before, was re-applied (2nd salinity stress). Increasing NaCl concentrations resulted to a decrease in growth rate during 1st salinity stress. Also, irradiated explants had higher survival percentage, shoot number and shoot fresh weight than non-irradiated ones. In 2nd salinity stress, only the irradiated explants under 160 mM NaCl had decreased in shoot number compared to other salinity treatments. In vitro-regenerated plants were rooted and acclimatized in the greenhouse and evaluated under normal and saline conditions (3rd salinity stress). A sharp decrease in the survival percentage and leaf number observed with an increase of salinity, while irradiated plants had more survival rate and leaves number than non-irradiated plants. In addition, as the salt concentration increased, the leaf burn and yellowing rate increased and its intensity was higher in non-irradiated plants. Overall, banana shoot tips exposed to different doses of gamma irradiation had higher growth parameters under in vitro and greenhouse salt stress. However, further studies are required to evaluate agro-morphological characteristics of these mutants in the field conditions under salinity stress.