Effect of Grafting Rootstock on the Antioxidant Capacity and Content of Heirloom Tomatoes (Solanum lycopersicum L.) in Hydroponic Culture

Abstract

Heirloom tomato varieties are in demand by consumers due to high antioxidant levels. However, these varieties are difficult to produce and are prone to disease. To overcome these problems, heirloom tomatoes may be cultivated in hydroponic systems and grafted onto disease-resistant rootstocks. However, it is unknown if the antioxidant content and capacity are affected by grafting. In this study, heirloom (Black Krim and Green Zebra) and standard (Big Beef) varieties were grafted onto wild type (WT) or productive rootstocks (Arnold and Supernatural). The tomatoes were harvested at maturity, freeze-dried, and ground into a powder. Lycopene was extracted using hexane, and the content was determined spectrophotometrically at 503 nm. The antioxidant capacity of methanol extracts was evaluated by the 2,2′-azino-di[3-ethylbenzthiazoline sulfonsyr]sulphonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, whereas the phenolic content was determined using the Folin–Ciocalteu assay. Interestingly, the grafting of Big Beef and Green Zebra onto Supernatural rootstock resulted in an increased antioxidant capacity, as determined by the DPPH assay. Moreover, the phenolic content was changed for Big Beef grafted onto Arnold, and Big Beef and Green Zebra grafted onto Supernatural. Taken together, these results indicate that certain combinations of standard and heirloom tomato varieties and productive rootstocks may influence the antioxidant capacity and phenolic content. These results may be used to guide producers when choosing rootstocks for cultivating hydroponic tomatoes.

Interspecific Hybrid Rootstocks Improve Productivity of Tomato Grown under High-temperature Stress

“…Furthermore, slight increases of b-carotene, total phenols, and total antioxidants were found among the grafted plants when compared with nongrafted tomato plants (Manickam et al 2021;Pugalendhi et al 2021). The antioxidant capacity and phenolic content of heirloom tomatoes were enhanced when grafted onto wild-type rootstock (Greathouse et al 2021). Hence, the effect of grafting on the quality of fruits depends mostly on the type of rootstock.…”

Impact of wild solanaceae rootstocks on morphological and physiological response, yield, and fruit quality of tomato (Solanum lycopersicum L.) grown under deficit irrigation conditions

“…Grafting is a historically validated technology that is still used in agricultural practices due to its effectiveness and usefulness in improving agronomic characteristics [ 56 ]. This technique allows the plant to perform better in morpho-physiological aspects and even overcome stress-related conditions [ 25 , [57] , [58] , [59] , [60] ], as well as potentially improve yield and fruit quality [ 59 , 61 ]. However, the procedures involve technical difficulties due to the compatibility between plants to be grafted, since a low affinity in the rootstock-scion combination can lead to slow growth and, in some cases, lower yields [ 62 ], due to vascular combinations not completing the healing/scioning process [ 57 ].…”

The essential role of jasmonate signaling in Solanum habrochaites rootstock-mediated cold tolerance in tomato grafts

“…Antioxidant enzymes, such as POD, SOD, and CAT, function as ROS scavengers, lowering their concentrations and alleviating oxidative damage induced by low temperature. Increasing evidence suggests that grafting can confer cold resistance in plants by regulating the activities and expression profiles of the antioxidative system [ 34 , 35 ]. Hetero seedlings showed higher activities of POD, SOD, and CAT, and lower ROS and MDA contents compared with Holyc seedlings ( Fig.…”