Iranian Journal of Horticultural Science and Technology
Year:2008 | Volume:8 | Issue:4|Papers Count:6

Elm is one of the most frequent trees of world landscape which is used in Isfahan green areas. Regarding different characteristics observed among these trees, in this study genetic diversity of 20 elm genotypes from four different locations of Isfahan was evaluated using RAPD and ISSR markers. Ten RAPD primers amplified 73 bands, 70 of them were polymorphic. Banding patterns were transformed into binary data of presence–absence and matrices were processed using NTSYS pc 2.02 software program. Mantel correspondence test was conducted to choose the best similarity coefficient among Daice, Jaccard and SM. The dendrogram was constructed using Jaccard coefficient and UPGMA algorithm. DN4 genotype was separated from others in this dendrogram. Grouping of genotypes showed high correlation with their locations. Among 16 ISSR primers, 7 primers showed acceptable polymorphism, were amplified 117 bands. After grouping, the genotypes DN4 and AN5 were separated from others, demonstrate their genetic distance from other genotypes. The PCA (Principal Component Analysis) confirmed the results of clustering. The combined data of two markers, in most cases confirmed the individual results each marker. Overall, results showed that the genotypes of south region of Isfahan had less differences showing possible same origin when compared to the other regions.

Iranian daffodil, a beautiful and fragrant flower, is one of the oldest ornamental flowers that historically reported before Hegira. The purpose of this study was to evaluate the intra- and inter- population genetic diversity and phylogenetic relationships of Iranian (southern Khorasan, Khuzestan, Kohkiloye and Boyerahmad, Fars, Mazandaran and Golestan provinces) and some exotic daffodils using RAPD markers. Foutteen of 50 random primers showed scorable and significant polymorphism between genotypes. Pair-wise comparisons of unique and shared polymorphic amplification products were used to generate simple matching coefficients. The similarity coefficients were used to construct a dendrogram by Unweighted Pair-Group Method with Arithmetic Averages (UPGMA) using NTSYS-PC. Average similarity coefficients calculated 0.81 ranged from 0.88 (endemics) to 0.48 (exotics). The resulted cluster was subdivided into 9 subgroups. Present results showed variation in exotic genotypes that was more than that of native populations. As wide genetic base is a important issue in plant breeding thus it is necessary to include this in daffodil breeding programs. Among random RAPD primers UBC-96 of 5'-GGCGGCATGG-3' sequence differentiated genotypes into two groups. Therefore, the mentioned primer could be applied for effective preliminary screening of single and double daffodils and saving the time needed for flowering.

The effect of four concentrations of humic acid (HA), (0, 100, 500 and 1000 mg l-1) incorporated in nutrient solution, were investinated on the physiological and morphological characteristics of Gerbera jamesonii L. cv Malibu. Application of HA (500 and 1000 mg l-1) could increase calcium accumulation in leaf and flower shoot tissue. These treatments also had the greatest effect on increasing vase life and decreasing bent neck incidence with respect to control as 1000 mg l-1  increased vase life by 3.66 d. HA application significantly increased membrane stability and lowered ion and anthocyanin leakage from petals, but had no effect on praline accumulation in bent neak place. Improving effects of HA might be related to its direct action through hormone-like activities (especially cytokinin-like) or indirect ones through improving calcium uptake that lead to increasing mechanical resistance of cell wall, membrane stability or interfering in ethylene biosynthesis.

Gametophytic self-incompatibility of almond (Prunus dulcis M) controlled by a single locus with several allelic variants. In this study, the S-alleles of 16 Iranian and 6 foreign almond cultivars were investigated by single and multiplex PCR technique with different set of oligonucleotide primers. Application of AS1II and AmyC5R primers with single PCR resulted in amplification of 9 known self-incompatibility alleles S1, S2, S3, S5/10, S7, S9, S11, S12, and S13. Four bands with different sizes from PCR products of known S-alleles were detected in Iranian almond cultivars (Mamaei, Raby, Sahand, Shirbadam, Hajmirzaei and Khorshidi) which may be related to new S-alleles. Multiplex PCR using the AS1II, AmyC5R and CEBASF primers verified the results of single PCR. Furthermore, it was also able to identify Sf-allele in self-compatible cultivars such as Tuono, Genco and Falsa Barese. From 32 S-alleles in Iranian almond cultivars only 28 were identified by using these primers. Two S-alleles for 12 cultivars and one S-allele for four cultivars were identified. S2, S7, S13, S3 and S10 alleles were more frequent than others in Iranian almond cultivars. This technique provides a precise and rapid method for identifying S-alleles from the genomic DNAs of almond cultivars.

Thirty-seven Iranian and three exotic garlic clones were studied for evaluation of genetic diversity using 12 morphological traits based on introduced descriptor. Cluster analysis using UPGMA method placed most of clone in separated groups with high correlation between morphological traits and geographical distribution. Iranian garlic clones and exotic one were located in 4 and 3 groups respectively. Nine clones from west of Iran with large white bulbs were located in first group. In 2nd group there were 4 clones among them Khaf had highest number of cloves. Ghermez Azarshahr, Ghermez Shahrekord, and Tabriz were located in 3rd group. The 4th group with 19 clones and high diversity was the largest group of dendrogram. The clones from north and south of Iran with significant distance were in this group. There was significant correlation between some of studied traits.

To investigate preharvest drop of Italian orange (Citrus sinensis cv. ‘Italian’), four gardens choose in different areas of Sari city in Mazandaran province in north of Iran. Results showed that averagely 7% of mature fruits abscised in a short time before harvest. Regarding to average yield of this cultivar in on year, more than 5 tons fruit abscised per hectare, annually. To evaluate possibility of preharvest drop reduction in ‘Italian’ orange, an experiment was conducted in randomized complete block design with four replications, in Baharestan and Mahdasht gardens in Sari. Treatments included: 1) control 2) 2,4-D (20 mg l-1) 3) 2,4-D (20 mg l-1)+urea (1%) ) 2.4 -D(20 mg l-1)+Zinc sulfate (0.5%)  5) 2,4-D (20 mg l-1)+sucrose (1%)  6) 2,4-D (20 mg l-1) +GA3 (15 mg l-1) 7) GA3 (15 mg l-1)+urea (1%). From spraying (9 weeks before harvest) to harvest, abscised fruits were counted every week, and finally abscission percentage in different treatments was calculated. In both gardens, abscission amounts in all treatments except to 7 showed significant reductions compared to control. In Baharestan, treatments 2, 3 and 5 with 64%, 60% and 65%, respectively, and in Mahdasht, treatment 2 with 66% had the highest effects. In average, 60% abscission reduction was equal to 3 tons increase in yield.