Effects of Temperature and Gibberellic Acid on Forcing and Quality Improvement of Iris (Iris hollandica cv. ‘Blue Magic’) Cut Flowers

In order to accelerate forcing, reduce the production period and to extend the vase life of Iris hollandica cv. ‘Blue Magic’ cut flowers, an experiment was performed in the research glasshouse of the Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran, in 2007. The experiment was carried out as factorial based on completely randomized design with three replications. Factors were temperature (5, 10 and 15°C) and gibberellic acid (0, 300 and 600mg/l). The concentration of 600mg/l gibberellic acid at 5°C accelerated sprourting and flower appearance and increased stem length, vase life of cut flowers and percentage of total soluble solid of petals as compared to other treatments. Furthermore, treating cut flowers with 600 mg/l gibberellic acid significantly increased the anthocyanin of petals and chlorophyll content of leaves. Also, reducing the temperature to 5ºC significantly increased  the anthocyanin of petal

Analysis of Fruit Skin Chlorophyll and Its Derivatives as a Valid Index in Determination of Commercial Maturity of Pear (Pyrus communis L.)

Fruit maturity at harvest is one of the most effective factors determining the increase of storage time and quality of pear fruit. One of the suitable fruit maturity indices during commercial harvest date of pear fruit is the change of its ground color. In this research, changes of proto-chlorophyll and its derivatives including a, b and total chlorophylls in 9 cultivars of pears namely: Spadona, Bartlett, Beyrouti , Dargazi, Dutchess, Shahmiveh, Felestini, Coscia and Louise Bonne during four different times, two weeks before commercial fruit maturity, commercial fruit maturity time, one and two months after fruit storage were evaluated. Measurement of chlorophyll was performed using spectrophotometric method and the amount of single spectrum light absorption under wave lengths of 625, 647, 664 nanometer. The most content of chlorophyll a and b and total chlorophyll in commercial maturity stage and different stages of storage devoted to Spadona that have clear difference in comparison to the others, but Felestini cultivar shows the less extent of the above mentioned factors during different stages of the evaluation. Also, in all stages of the experiment, chlorophyll a was greater than chlorophyll b. In most cultivars, changes of chlorophyll showed clear downfall with low standard deviation during the four different times. Based on the results, it can be concluded that evaluation of skin chlorophyll and its changes are valid and usable indexes in determination of commercial maturity of fruit in understudy cultivars except Shahmiveh and Louise Bonne cultivars

Morphological Characteristics, Genetic Diversity and Classification of Chrysanthemum Genotypes

Chrysanthemum is one of the most important ornamental plants. The genus chrysanthemum is a popular cut flower, medicinal and pot plant. Morphological traits such as cut rooting and leaf characteristics and genetic diversity among 50 genotypes of chrysanthemum morifolium were analyzed. Based on analysis of variance of data all traits in the studied genotypes showed significant differences at 1% level. The results of correlation coefficient indicated a positive and significant correlation between stem length, leaf length, leaf width and leaf serration number.The leaf length showed the highest correlation (r = +0.90**) with leaf width. Results showed that stem length and petiole length had the highest (h2>80%) heritability. Cluster analysis according to the morphological traits using the Ward method classified all the genotypes into six groups. In this classification, two genotypes (‘Takapo’ and ‘Poloneh’) were classified into one cluster that was characterized by tall stem and low branch number. In this study, canonical discriminant analysis of 20 morphological traits revealed that 3 canonical discriminant variables explained 89.6% of the total variation among genotypes. Results revealed that among the studied traits, number of cutting root, leaf size, petiol length, stem length, number of branches and number of offsets were the most important traits for discriminating among chrysanthemum genotypes. The results of this study indicate that these traits are useful for selecting and identify superior genotypes of chrysanthemum germplasm. Using some of the genotypes belonging to cluster A (with a small size of plant) and genotypes belonging to cluster E (with a large size of plant) as parents can be practiced as a criteria for breeding programs