tBiochar is an amendment that can be used for enhancing soil water storage which may increase cropproductivity. The objective of this study was to investigate the effects of biochar on physiology, yield andquality of tomato under different irrigation regimes. From early flowering to fruit maturity stages, theplants were subjected to full irrigation (FI), deficit irrigation (DI) and partial root-zone drying irrigation(PRD) and two levels of biochar (0% and 5% by weight). In FI, the plants were irrigated daily to pot waterholding capacity while in DI and PRD, 70% of FI was irrigated on either the whole or one side of the pots,respectively. In PRD, irrigation was switched between sides when the soil water content of the dry sidedecreased to 15%. The results showed that addition of biochar increased the soil moisture contents in DIand PRD, which consequently improved physiology, yield, and quality of tomato as compared with thenon-biochar control. However, leaf N content and chlorophyll content index (CCI) were decreased signif-icantly in biochar treated plants. Furthermore, given a same irrigation volume, PRD offered advantagesover DI in improving water use efficiency, leaf relative water content, membrane stability index and fruityield. Overall, fruit quality was improved under reduced irrigation (i.e. DI and PRD) as compared with FI.It was concluded that incorporation of biochar under DI and particularly, PRD might be a novel approachto improve water productivity and quality of tomato.
Agricultural Water Management, 2014, Vol 138, p. 37-44
Biochar; soil water content; water use efficiency; chlorophyll content; nitrogen; fruit quality