Resistant Rootstocks Utilization for Fusarium Control (Fusarium oxysporum f. sp. lycopersici Snyder & Hansen race 3) in Tomato (Lycopersicon esculentum Mill) under Shade Conditions
The present study is aimed to evaluate the performance of four tomato rootstocks: Multifort (DeRuiter), Aloha (Takii), RT-160961 (Takii) and Vigostar 10 (Hazera) grafted with five tomato bola hybrids: TL-41500 (Zeraim Gedera), Imperial (Enza Zaden), Pilavy (Rogers), Liberty (Hazera) and Aegean (Enza Zaden), inoculated with the fungus Fusarium oxysporum f. sp. licopersici race 3 (Fol 3), which causes Fusarium based on disease resistance and productivity. The study was conducted for six months, performing monthly reviews of the disease development. It was revealed that the Multifort material was resistant, as no plants were observed in the presence of symptoms of the disease in any of their combination with the five hybrids. Moreover, Vigostar 10, Aloha and RT-41500 were tolerant, due to the fact that there were some plants with symptoms of the disease. Regarding performance, the best combinations were obtained with the rootstocks Multifort and Vigostar 10 grafted with the Imperial hybrid, in which there was an increase in production of about 170% compared to the hybrid without grafting. Differences in cell organization on the hybrid Imperial photomicrographs were revealed by roots of Multifort and Vigostar 10 standards, which is highly susceptible to Fol 3. Similarly, the presence of structural barriers such as tyloses Multifort and Vigostar 10 standards was observed, acting as a resistance mechanism in the presence of Fol 3. An increased presence of polyphenols compared with the hybrid Imperial (susceptible), was revealed by histochemical studies concerning the standards (Multifort and Vigostar 10), considering these compounds as a factor in the resistance by employers; opposite to this, soluble and insoluble polysaccharides did not reveal enough evidence relating the resistance of those standards.