Identification of potential rootstocks for tomato grafting from bacterial wilt screening trials in North Carolina
Bacterial wilt (BW), caused by Ralstonia solanacearum, is a severe disease of tomato worldwide. In North Carolina of the US, the severity and incidence of BW have increased in recent years. To combat the problem by breeding, evaluation of potential resistant breeding lines derived from Hawaii 7998 (HI7998) was started in 2009 in a field in western NC where BW has been endemic for several years. The objectives of the experiment were to develop improved lines with resistance to BW. Disease-free plants selected from the 2009 and 2010 study and putative resistant lines from the World Vegetable Center (formerly AVRDC) were used as parents in crosses to advanced breeding lines lacking BW resistance. We continued selection for BW resistance over the years. The problem with the selection process was that there was a negative correlation between fruit size and BW resistance, which has been a challenge to improve both traits simultaneously. With the advancement of grafting technology, it is possible to use the BW resistant lines even with smaller fruit size as rootstocks. Considering that opportunity, there are at least four lines that can be utilized as rootstock for grafting. These lines have shown resistance to BW consistently over the years and locations. These lines are being evaluated for their suitability as rootstock at a broader scale.
Panthee, D.R., Kressin, J. and Piotrowski, A. (2021). Identification of potential rootstocks for tomato grafting from bacterial wilt screening trials in North Carolina. Acta Hortic. 1302, 169-176
fruit quality, Ralstonia solanacearum, rootstock breeding, tomato