The present work was carried out during 2019/2020 and 2020/2021 successive growing seasons at the private organic farm, Bani Salama village, Mansha'at Al Qanater Al Khayriyah County, Giza Governorate, Egypt, to investigate the efficacy of different organic matters, i.e., compost, plant residue, cow manure, vermicompost and humic acid on management of tomato root-rot disease incidence to increase the quality and quantity of tomato fruits. Fusarium oxysporum, F. solani, Pythium sp., Rhizoctonia

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... lani and Sclerotium rolfsii were isolated from rotted samples of tomato roots. Pathogenicity test proved that these fungi are the main causal pathogens of tomato root-rot diseases. All tested organic matters showed a significant decrease in the linear growth of the isolated pathogenic fungi in vitro. Adding the different organic matters, i.e., plant residue, cow manure and compost "plant residue + cow manure" at the rate of 1.2 kg/m 2 to the soil before transplanting Super Strain B hybrid tomato cv., as well as dipping tomato seedlings in diluted (1:50), as recommended dose of vermicompost or humic acid separately significantly reduced disease incidence in vivo. Also, assessment the highest increase in the survived plants in comparison with control treatment during both growing seasons. Compost, as rich organic fertilizer at the rate of 1.2 kg/m 2 caused the highest decrease in disease incidence and recorded also, the highest increase in vegetative growth "plant height, No. of brunches/plant and No. of leaves/brunch"; yield parameters; fruit quality "total soluble solid (TSS), vitamin C, protein and total carbohydrate"; chemical components of flavonoid, total phenol and the enzyme activities of peroxidase (PO), polyphenol oxidase (PPO), chitinase and β-1,3 glucanase during both growing seasons. On the contrary, the plant residue showed the least effect treatment. No clear significant differences were noticed between the other treatments in comparison with control treatment.