Characterization of the p3-VvAGL11 marker for stenospermocarpic seedlessness in Euvitis × Muscadinia grape hybrid progenies

Abstract

Stenospermocarpic seedlessness from Vitis vinifera L. is being introgressed into muscadine grape (Vitis rotundifolia Michx.) germplasm through the use of a cross-fertile hybrid of the two species. Recently, a sequencetagged site (STS) molecular marker, p3_VvAGL11, has been developed which enables detection of the dominant allele controlling stenospermocarpic seedlessness in V. vinifera. This marker was evaluated in six Euvitis Planch. · Muscadinia Planch. hybrid progenies to determine its association with seedlessness in this material. The presence of the 214-bp seedlessness-associated p3_VvAGL11 allele in seedling vines resulted in a nearly 3-fold reduction in mean seed fresh weight (MSFW) and significantly reduced mean seed weight per berry (MSWB), percent berry weight composed of seed (BWCS), and mean berry weight (MBW). When the lack of lignified seed was used as the determinant of seedlessness, the p3_VvAGL11 marker was able to correctly judge seedlessness in ’85% of the progeny. Analysis of seedlessness in the progenies was hampered by poor vigor and fruiting ability of the hybrid seedlings. The p3_VvAGL11 marker shows potential to speed the introduction of the stenospermocarpic seedlessness into Muscadinia germplasm by identifying seedless progeny at the seedling stage.