Six greenhouse trials of five commercial products marketed as systemic resistance (SR) and plant growth promotion (PGP) inducers were evaluated on tomato (Lycopersicon esculentum Mill.) over a 21-month period. The effect of the inducers on treated plants was measured by monitoring plant growth and disease suppression after inoculation with either plant pathogenic bacteria or nematodes. The commercially available SR/PGP inducers included a bacterial suspension [Companion (Bacillus subtilis GB03)], two plant defense elicitors with nutrients (Keyplex 350DP plus Nutri-Phite, and Rezist with Cab'y), natural plant extracts (Liquid Seaweed Concentrate and Stimplex), and a synthetic growth regulator (Actigard 50W). Growth enhancement was noted in some trials, but the parameter of growth affected often varied with trial. Response to Actigard treatment included significant suppression of bacterial spot [Xanthomonas campestris pv. vesicatoria (Xcv)] in three of the six trials. Companion, Keyplex 350DP plus Nutri-Phite, Rezist and Cab'y, and seaweed products induced only partial disease suppression of bacterial spot in inoculated tomato plants. The alpha-keto acids plus nutrients (Keyplex 350DP plus Nutri-Phite) increased plant growth by 14.3% and improved root condition compared to the untreated control following exposure to nematodes. Results are encouraging, if not consistent, and with a greater understanding of the SR system and the conditions related to product efficacy, such materials may become effective tools for production agriculture.
environments. One such disease is bacterial spot caused by Xanthomonas spp. Multiple bacterial spot resistance loci originating from wild tomato species and breeding lines have been mapped to chromosome 11. The resistance locus Xv3 / Rx4 , derived from H7981
‘Juneprince’ peach [Prunus persica (L.) Batsch.] has been released to extend the season in moderately low-chilling areas suc5as south Georgia and as a replacement for ‘Coronet’ in medium-chilling areas. ‘Fireprince’ peach has been released to provide a cultivar for the Southeast in the season preceding ‘Redglobe’.
‘Contender’ peach [Prunus persica (L.) Batsch] is being released to fulfill the need for a high-quality, consistent-cropping, yellow-fleshed freestone cultivar ripening between ‘Loring’ and ‘Elberta’.
‘Carolina Belle’ peach is being released to fill the need for a firm, white-fleshed peach intended for local markets, and is proposed as an alternative to ‘Raritan Rose’.
‘Sunland’ peach [Prunus persica (L.) Batsch] has been released to provide a cultivar well-adapted to the southeastern United States that ripens slightly later than ’Harvester’. ‘Sunland’ is similar to ‘Harvester’ in color and firmness, but has larger fruit.