Ameliorative Effects of Organic Fertilizer, Trichoderma and Silicon on Productivity and Quality of Tomato Grown under Contaminated soil Conditions

Contamination by HMs has emerged with the industrial revolution and then sharply increased in urban due to due to increased population activity and in rural areas due tointensive agriculture production to meet food demand of a growing population. Intensive agricultural pollution arises from both natural (geological) and anthropogenic activities i.e., various stationary and mobile sources (Bilos et al., 2001). Agricultural amendments e.g., sewagesludge, mineral synthetic fertilizers and pesticidesrelease large quantities of HMs (Anagawa et al., 2019), exceeding critical limits i.e., 60mg/kg Pb and 70mg/kg Cu in the soil according to FAO/WHO (2001).This is acutely evident inEgypt, especially in areas adjacent to the highways, domestic wastewater and industrial zonewhich pose a critical concern to plants,environment and human at the end of the food chain. In northeastern of the Delta, particularly in Talkha, an industrial and agricultural city, the soil is heavy in texture with relatively high pH, low organic matter and contaminated by copper and lead, besides low quality irrigation water which was a mixture of industrial waste from El Delta Fertilizers Co. and sewage and agricultural wastewaters. THE PRESENT study was carried out during the summer seasons of 2017 and 2018 in Talkha city, Dakahlia Governorate, Egypt near El-Mansoura-Damietta highway and El Delta Company for Fertilizers and Chemical Industries, where lead (Pb) and copper (Cu) levels in the soil exceed the permissible levels. Therefore, the aim of this study was to alleviate the adverse effects of heavy metals (HMs) on tomato plant (Solanumlycopersicum L.) Super Strain B F1. Twelve treatments were conducted which were the interactions between two silicon (Si) foliar spraying (without or 300 ppm Si) and six soil amendments : 100% chemical fertilizers (CF), 50% farmyard manure (FYM), 100% FYM, 100% CF+ Trichoderma spp. (T.), 50% FYM + T. and 100% FYM + T. Data indicate that Pb and Cu were accumulated in tomato organs to hazardous levels in the following descending order : roots > shoots > fruits and shoots > roots > fruits, respectively which consequently severely reduced tomato plant growth and fruit yield and fruit quality. Results also, showed that the application of Si treatment sole or in combination with soil amendments markedly enhanced plant height, dry weight, total chlorophyll, number of fruits/plant, total yield/fed, Vitamin C, acidity %, TSS and taste index, where as, reduced Pb and Cu concentrations in different plant organs, bio-concentration factor (BCF) and translocation factor (TF). However, Si + FYM + T. treatment was superior in these respects, therefore increased the net return. Also, negative correlations were obtained between fruit yield and BCF of Pb or Cu and between taste index and TF of Pb or Cu.