Produção de haplóides de melão (Cucumis melo) por meio de cruzamento interespecífico entre melão e outras espécies da família Cucurbitaceae.

Abstract

The growing demand for higher quality melon fruits leads breeders to always seek superior genotypes, mainly through the development of simple hybrids from the crossbreeding between two purebred lines. However, obtaining strains requires plenty of time, which requires the development of more efficient techniques, such as dihaploidization. This technique is based on obtaining a haploid individual, which has a number of chromosomes halved, and these are then duplicated in order to obtain a completely homozygous diploid individual. Interspecific crosses are one of the techniques used to obtain haploids, in which pollen, although genetically unviable, maintains the physiological functions of both pollen tube and fruit formation, generating haploid embryos. Given the above, this study aimed to obtain haploid embryos of melon through interspecific cross between Cucumis melo and other cucurbits. The experiment was carried out in a greenhouse at Embrapa Agroindústria Tropical, from September to November 2017. The experimental design was completely randomized, in a factorial scheme (2 x 6), with two types of melon and 6 other cucurbits. The Goldex hybrid of the commercial type Yellow (Cucumis melo var. inodorus) and a cantaloupe (C. melo var reticulatus) strain of the Embrapa Melon Plant Breeding Program were the pollen recipients. As pollen donors, commercial varieties of cucumber, gherkin, watermelon, pumpkin and winter squash were used. As experimental control, all genotypes were self-fertilized. Of all the crosses, only the controls of melon and cucurbits were successful, with fruit formation. The success rate of the interspecific crosses was 0%, with all pollen receiving flowers of the cucurbits aborting before the production of embryos. The production of haploid embryos from the melon via an interspecific crossing was not feasible for all cucurbits tested.