ANNOUNCEMENTS
In Semi-arid tropics water is scarce; hence reuse of treated wastewater offers a reliable and perennial source. The availability of additional water opens-up a scope of revenue generation for the farmer through flower, fodder or cash crop production etc. This additional income has the potential to bring significant difference in the life of resource-poor farmers. The presence of heavy metals in treated wastewater severely diminishes its irrigation potential. Useful utilization of such wastewater remains a challenge. Heavy metal impact on soil and environment is a contemporary reality. Among the heavy metals, chromium (Cr) is ubiquitous in wastewater. Chromium in its hexavalent form is soluble and penetrates the entir food chain once it enters through irrigation. Chromium is released into the environment by a large number of industrial operations such as electro plating, chromate manufacturing, leather tanning and wood preservation. Cr (VI) is toxic, carcinogenic and mutagenic to animals as well as humans and is associated with decreased plant growth and changes in plant morphology. Grafting has been sustainable tool in providing plant tolerance to various abiotic stresses, in particular of fruiting vegetables. This study focused on evaluating the yield and heavy-metal exclusion capacity of grafted and non-grafted tomato (Solanum lycopersicum L.) varieties. Grafted and non-grafted tomato varieties were cultivated using effluent from constructed wetland to which 0.02 mg/L of Cr (VI) was artificially added using stoichiometric amount of potassium dichromate. Two eggplant root stock R1 (EG 203) and R2 (EG 195) was used in combination with scions from three tomato varieties V1 (HEEMSOHNA), V2 (Dutch), V3 (NIRUPAMA), keeping non-grafted tomato varieties as control (i.e. NGV1, NGV2 and NGV3). The study found that plant growth, yield and heavy-metal uptake in plant tissue (terminal leaf or fruit) varies among different combinations, in which grafted tomato plants of R1V2 (EG 203 X Dutch) combination gave highest yield for tomato and showed minimal and zero concentration level in the terminal leaf tissue and fruits respectively. These finding can help us to develop suitable grafted varieties enabling utilization of wastewater with Cr (VI) for revenue generation activities such as seed production.
