Developing the Molecular Markers for Zucchini Yellow Mosaic Virus Resistance in Winter Squash (Cucurbita moschata)

Squash (Cucurbita spp.) has been grown by humans for fruits and seeds over 10,000 years. Zucchini yellow mosaic virus (ZYMV) is infecting squashes in Taiwan and it is one of the most destructive virus. Breeding for ZYMV resistant squash is the best way to control it. Molecular markers could shorten the breeding process greatly. The objective of this study is to tag ZYMV resistance with molecular markers. A ZYMV resistant line, “Nigerian Local, (NL)”, was crossed to susceptible line, “Local Papaya, (PY)”and a F₂, BC₁ and BC₄ populations were generated for tagging. The result suggested that the inheritance of ZYMV resistance in the near isogenic lines derived from PY x (PY x NL) is controlled by two dominant complemantary genes. A total of 631 random amplified polymorphic DNA (RAPD) and bulk segregant analysis (BSA) were performed to search useful markers. There were seven polymorphic bands which were converted to sequence characterized amplified region (SCAR) or cleaved amplified polymorphic sequence (CPAS) markers. After linkage analysis, only three markers were shown linkage to ZYMV resistance and would be useful in marker-assisted selection (MAS) and for ZYMV resistance in squash.