Pomological, chemical and molecular characterization of some hawthorn (Crataegus spp.) genotypes

In this study, phenological, pomological, chemical and molecular characterization of a total of 65 hawthorn genotypes, 53 naturally grown in our country's flora and 12 located in the national hawthorn collection garden of the Apricot Research Institute, were carried out. In the phenological observation, pomological and chemical analyzes, 3 jujube and 3 apple genotypes were also included. Species identification was made in the hawthorn genotypes included in the study and 13 different hawthorn species were determined. In the fruits of hawthorn, apple and jujube genotypes included in the thesis study; pomological characteristics such as fruit weight (g), fruit dimensions (mm), seed weight (g), fruit pulp/seed ratio (%) and L*a*b* values were determined. It was determined that fruit weight values ranged from 13.7 g to 0.46 g and the highest fruit weight was 13.7 g in genotypes 50-2 (C. orientalis. var. obtusata) and 13.64 and 50-1 (C. orientalis. var. obtusata) genotypes has been done. In order to determine the chemical properties of the fruit samples belonging to the genotypes in the study, pH, soluble solid content (%), titratable acidity (%), vit C (mg/100g), total phenolic substance amount (mg GAE/100), sugar components (g/100 g) and phenolic components (mg/100 g) analyzes were made. Considering the pH, SSC, titratable acidity, vit C and total phenolic substance ratios, the highest values were 91-1 (4.28), 91-1 (22.40 %), 90-1 (2.2 %), 91-1 (19.1 mg/100 g), and 91-1 (838.72 mg GAE/100 g) respectively genotypes. It was determined that genotype 91-1 had high values of SSC, vit C and total phenolic substance concentration. In addition, different amounts of gallic acid, catechin, epicatechin, epigallocatechin gallate, rutin and caffeic acid components were determined in the genotypes that were chemically analyzed. In the molecular characterization studies of the research, 14 ISSR primers, 7 SRAP primer combinations and 8 SSR primer pairs were used. The highest polymorphism rate was obtained from SSR markers with 100 %, followed by SRAP with 90.62 % and ISSR with 87.32 %. According to the data obtained in the molecular characterization studies, it was determined that the Crataegus L. species included in the research and collected from different regions of Turkey show a great genetic diversity and are an important genetic resource that should be evaluated in hawthorn breeding studies in terms of pomological and chemical content.