2019 ASHS Annual Conference

Our objective was to observe the effect of interspecific grafting combinations among Capsicum spp. as compared to non-grafted and self-grafted checks. Three commercially available C. annuum cultivars (California Wonder, Dulcitico and Natalie) were chosen as scions, and grafted onto commercial cultivars Habanero Early (C. chinense) and Aji Rico (C. baccatum). Field trials were conducted at West Madison Agricultural Research Station (WM, Madison, WI) in 2017 and 2018 and on the campus of the Tecnólogico de Costa Rica in San Carlos, Costa Rica (CR) in 2018. No significant difference was observed among grafted, self-grafted and non-grafted plants for marketable yield; however, at WM we did observe a 22 % increase in marketable yield in all scions grafted onto Habanero Early. Similarly, an average increase of 15% and 5% was observed in the Dulcitico-Aji Rico combination at WM for 2017 and 2018 respectively, whereas the combination Natalie-Aji Rico tended to decrease yield in by 9% over both years, suggesting scion by rootstock interactions. Significantly higher yields were observed at WM in 2017 compared to CR. Aji Rico rootstock tended to result in reduced days to flower on Dulcitico and Natalie scions across all locations when compared to non-grafted plants. Habanero Early rootstock tended to result in reduced days to fruit on all scions across all locations. Natalie grafted onto Habanero Early resulted in significantly larger fruit size compared to non-grafted plants. No differences in fruit quality characteristics were observed among grafted, self-grafted and non-grafted plants.