Effectiveness of grafting and biostimulants application as a strategy for enhancing tomato nematode resistance

M. Cukrov, I. Podrug, B. Urlić, M. Mandušić, K. Žanić, E. Radpudić, A. Slatnar, G. Dumičić
Various biostimulants have recorded nematicidal effects through enhancement of host-plant resistance or direct nematoxicity. Additionally, grafting scions on nematode-resistant/tolerant rootstocks proved to be effective regulatory measures. The aim was to determine the effect of grafting and biostimulants application on non-infested and root-knot nematode (Meloidogyne incognita) infested tomato plants. Transplants of ‘Matissimo’ tomato (self-grafted or grafted on rootstock ‘Arnold’ and ‘Maxifort’) were planted in six liters size pots with mixed substrate humus-peat, perlite and vermiculite (2:1:0.25 v/v) on April 16th. Half of the plants were infected with root-knot nematodes. Plants were treated with two biostimulants (Interra and Kendal Nem) while control plants were treated with tap water (74, 87 and 101 DAP). Nematode gall index (NGI) was ascertained 80 days after planting (DAP) resulting with ‘Maxifort’ (1.61 NGI) as the most affected rootstock, while Arnold (0.39 NGI) showed significant reduction in gall formation. Treatments with Interra resulted with a 40% increase of NGI compared with Kendal Nem and control treatments, which didn’t differ significantly. All three factors influenced leaf number at 64 DAP. Neither among rootstocks nor biostimulants have any differences in stem and root dry weight or chlorophyll concentration index been assessed. However, values of those traits were significantly higher in infested plants than in non-infested ones. SLA was highest (222.1 cm2 g‑1) in plants grafted onto ‘Arnold’ rootstock infested with nematodes and treated with Interra opposed to same, infested plants treated with Kendal Nem (124.9 cm2 g‑1). Early yield was influenced by all three tested factors ranging from 1.7 to 3.5 kg plant‑1, and applied treatment combinations differently affected its value. Shown results indicate that joint effectiveness of biostimulants and rootstocks can reduce the damage caused by nematodes and could be used for sustainable nematode management strategy.
Cukrov, M., Podrug, I., Urlić, B., Mandušić, M., Žanić, K., Radpudić, E., Slatnar, A. and Dumičić, G. (2021). Effectiveness of grafting and biostimulants application as a strategy for enhancing tomato nematode resistance. Acta Hortic. 1320, 283-290
DOI: 10.17660/ActaHortic.2021.1320.37
root-knot nematode, tomato grafting, rootstocks, biostimulants, tolerance

Acta Horticulturae