Influence of successive cycles of water stress on tomato production at fruiting stage

Abstract

Progressive reduction of water supply was imposed during early period (S1) and late period (S2) interceded by a recovery, with a moderate stress for first case and un intensive stress for second case, at fruiting stage of tomato (Lycopersicon esculentum Mill. cv. Rio Grand). The influence of this reduction on fruit production, shoot growth, water content (WC), relative water content (RWC), leaf area (LA), specific leaf weight (SLW), total soluble solids of fruit (T.S.S.) and maturity percentage of fruit were investigated. Repetition of water stress (S1+S2) was obviously reducing the shoot growth, fresh yield, WC, LA and maturity percentage, whereas that was not achieved in dry weight of fruits (FDW), RWC, SLW and T.S.S. Since, a significant difference was founded between the effects of S2 cycle and when that has been preceded by another one S1+S2 on accumulation of dry matter of fruit. Two successive cycles of water stress were doubled of FDW by two times of that registered in control. These results indicate that, during fruiting stage, the effect of gradually exposure of a moderate water stress period, followed by recovery, thereafter by another gradually exposure of un intensive water stress period, contributed to better accumulation of dry matter in fruit by an osmotic adjusting therefore improving water use efficiency, compared to the effect of only one high intensive of water stress applied during the second period. Repetition cycle of water stress may be useful to develop management systems for a reasonable production of tomato and thus reducing the needs of irrigation water in regions facing deficit of water supplies.