نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 جهاد دانشگاهی واحد آذربایجان غربی
2 دانشگاه ارومیه
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
ABSTRACT
Background and Objectives: Catharanthus roseus (Linn.) G. Don) is an important medicinal plant with a wide distribution that has attracted increasing attention due to its high pharmacological value and different biological activities such as antioxidant, antibacterial, antifungal, anti-diabetic, and anti-cancer. Besides alkaloids, this plant produces a wide range of phenolic compounds. Due to the effects of polyploidy on the growth and development of plants, chromosome doubling has been used as a method in plant breeding to increase the valuable desired compound levels and improve morphological characteristics, and these changes depend on the plant species and cultivar. Hence, the aim of this paper was to explore the possibility of using polyploidy as a breeding method to compare the growth traits also investigate total phenolic and flavonoid content as well as, polyphenolic compounds accumulation between tetraploid and diploid plants in 'Red Really' and' Polka Dot' cultivars.
Materials and methods: In this study, in vitro apical buds of seedlings of 'Red Really' and ' Polka Dot' cultivars, were treated by various concentrations of colchicine (0, 0/05, 0/1, 0/2 and 0/5 %) at three exposure time (24, 48 and 72 h). To distinguish the ploidy level of seedlings flow cytometry and chromosome counting were performed. After establishing tetraploid seedlings, total phenol and flavonoid content was measured. Extraction and analysis of phenolic compounds conducted using High-performance liquid chromatography (HPLC) analysis.
Results: In our experiment, the concentration and exposure time of colchicine and their interaction effected the tetraploidy percentage. karyotype analysis suggested that the number of chromosomes in the diploids species was 2n=2x=18 and tetraploids plants contained 2n=4x=36. The maximum tetraploidy frequency was observed at the 0.2% colchicine for 48h in 'Red Really' and 0.1% colchicine for 48h in ' Polka Dot'. The polyploid seedlings produced, visible changes in total phenol and flavonoid content compared to diploids. Also, gallic acid, caffeic acid, chlorogenic acid, rutin, coumaric acid, rosmarinic acid, quercetin, cinnamic acid and apigenin content increased compared to diploid plants.
Conclusions: Despite the high economic and therapeutic value of C. roseus, there has been scarce investigation of polyploidy induction on various cultivars of this plant, although there are previous protocols, but they may not be effective on all cultivars. According to our results, polyploidization caused a significant increase in polyphenolic compound contents, especially cinnamic acid, apigenin, and quercetin in "Polka Dot". On the other hand, induced tetraploids of both cultivars had a significantly higher content of total phenol and flavonoid. Also, our results showed that polyploidization allows the creation of plant forms containing greater amounts of biologically active compounds than their diploid counterparts and resulting polyploid lines have the potential to be used in breeding programs to develop C. roseus cultivars.
کلیدواژهها [English]
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