Evaluation of essential elements of sweet basil (ocimum basilicum l.) at different growth stages under deficit irrigation.

Sweet basil (Ocimum basilicum) is an annual herb plant belonging to the Lamiaceae family that is used as a drug, spice and fresh vegetable. In order to study the effects of different levels of water stress on some element of the plant, O. basilicum was subjected to deficit irrigation using four treatments viz. control, irrigated with 70% of soil water capacity (SWC), Treatment 1, irrigated with 50% SWC, Treatment 2, irrigated with 30% SWC and Treatment 3, irrigated with 10 % SWC. Plants were divided into four growth stages, Viz., vegetative (35 days after sowing, DAS), pre-flowering (49 DAS), flowering (63 DAS) and seed setting (77 DAS). Essential elements of leaves were investigated under these irrigation treatments at each growth stages. The results at the end of each growth stage indicated that there is no significant reduction in essential elements quantities compared to that of full irrigation control. The quantities remained high even in the lowest irrigation plants (T3, 10% SWC). The lowest irrigation plants accumulated, high nitrogen (N) Calcium (Ca) , magnesium (Mg), potassium (K) and phosphor (P), compared to control plants. Moreover, low irrigation helped Ocimum plants to accumulate less chloride than the full irrigated control. These results may be attributed to the ability of this plant to acclimate to water shortage.