Genetic variation in leaf characters of F1 hybrids of Chinese Jujube

To study the genetic characters of leaf variation in Ziziphus jujuba Mill., a 201-seedling natural crossing population was constructed with Z. jujuba 'Dongzao' and Z. jujuba 'Jinsi 4'. The progeny seedlings were genotyped and their male parents were identified using 8 SSR loci. After genotyping by Cervus 3.0, 84 alleles were detected in the population, with an average allele number of 10.5 and an average observed heterozygosity of 0.801. From the alleles, 111 individuals (55.5% of the total number of progeny) were identified as the progeny of 'Jinsi 4' with a confidence interval of 95%, and no progeny resulting from self-pollination of 'Dongzao' was detected. Leaves of the 'Jinsi 4' progeny were characterized based on leaf length, leaf width, leaf area, specific leaf weight and chlorophyll content. Leaf area gradually decreased, and the average size of progeny leaves was smaller than that of the parents' leaves; in fact, the leaf area of almost none of the progeny exceeded that of the parents. The leaf phenotypic characters conformed to a normal distribution. Specifically, the h2 of leaf area was as high as 0.9, and the h2 of leaf length, leaf width, chlorophyll content and leaf index exceeded 0.85. This study demonstrated the law of separation and variation in the leaves of hybrid progenies and provided a reference for constructing a genetic map with quantitative trait loci and selecting superior progenies.