بررسي برخي پارامترهاي فيزيولوژيك و تركيبات آلي جهت شناسايي ژنوتيپ هاي مقاوم و حساس به شوري در چغندرقند

Study of some Physiological) parameters and organic composition for selecting of salt tolerant and sensitive genotypes in sugar beet

In this study three sugar beet genotypes were selected based on some physiological and agronomical characteristics and had determined to be resistant, semi resistant and sensitive to salt were studied to identify relationship between physiological indices and organic compositions and the best method for determining tolerance and sensitive genetic resources in laborary and field conditions studying percentage of germination, initially seeds were planted in different osmotic pressure that were provided by mannitol solution and compared for seedling stability, and germination stability using randomized complete block design with two replications, and were grouped according to fisher and maurer index to tolerance, semi tolerance and sensitive. According to this grouping, tolerant genotypes had higher seedling stability and germination than semi- tolerant and sensitive genotype. These genotypes were also tested under natural salt stress of soil in Amir abad, Karaj. In comparison of genotypes for synthesis of praline, leaf soluble proteins, cytoplasmic membrane stability, there was no direct significant relationship between accumulation of praline and relative tolerance of sugar beet. Tolerant genotypes had higher cytoplasmic membrane stability and relative water content than other genotypes. Chlorophyl a had a significant and positive correlation with root yield. It was concluded that chlorophyll b has no requirement to salt stress for synthesis and is not under effect of this stress. In study of leaf soluble proteins, genotypes were classified in separated groups. Positive correlation of this character with relative water content and root yield shows that this character can be used as selection index for salt tolerance in sugar beet breeding programs.