Investigating the Possibility of Producing Double Haploid Lines in Some Selected Cultivars of Greenhouse Cucumber Through Induction of Parthenogenesis

Abstract

Cucumber with the scientific name Cucumis sativus L. is an annual plant of the Cucurbitaceae family. The genus Cucumis has approximately 30 species, two of which, namely cucumber (C. sativus L., 2n=2x=14) and melon (C. melo L., 2n=2x=24) have high economic importance. Cucumber is among the top 10 summer vegetables produced in the world. Its origin is the warm regions of northeastern India. Ensuring the food security of a country is considered the authority of that country. The hybrid seed production industry is growing in the large industrial world and has a high turnover, providing suitable and timely seeds is considered an important structure to maintain the capacity and ability to supply food. Haploid and double haploid technology through gametophytic embryogenesis and changing the expression of genes involved in the emergence of important agricultural traits provides the possibility of exploiting the genetic potential of genotypes and is a suitable approach for hybrid seed production. Product productivity can be increased to a great extent by using hybrid F1 varieties resulting from the crossing of pure lines with desirable traits. Pure lines are very valuable in breeding programs and genetic research. In this regard, a research was conducted in the research greenhouses of the Southern Agricultural and Natural Resources Research Center of Kerman province as a factorial experiment in the frame of a completely randomized design in 3 replications. Genotypes at 5 levels were considered as the first factor and radiation treatment at two levels of 300 and 350 Gy for the sterilization of greenhouse cucumber pollen seeds were considered as the second factors. The results showed that the ploidy level distribution in double haploid seedlings was the most haploid induced by the treatment of 300 Gy gamma ray radiation. The produced plants had half the number of haploid chromosomes and a combination of normal chromosomes and half chromosomes (mixoploid). The number of chromosomes in haploid plants was doubled by the laboratory treatment of colchicine with a concentration of 500 mg/liter for 24 hours. The results of this research showed that this method can be used to produce homozygous lines in breeding programs and produce parental lines in different genotypes of greenhouse cucumbers by removing the obstacles of seedling regeneration.