Guan'gai paishui xuebao (Jan 2023)
Effects of 6-BA on Growth and Endogenous Chemical Signals of Maize Seedlings under Partial Irrigation
Abstract
【Objective】 The synthetic cytokinin 6-benzyladenine (6-BA) is an exogenous regulator to promote plant growth, and the purpose of this paper is to study the effect of 6-BA on growth of maize seedlings watered by different irrigations. 【Method】 We compared two irrigation treatments each having two 6-BA treatments (with and without adding 6-BA): partial water deficit irrigation following a uniform sufficient irrigation (PD for without 6-BA, and PDT for with 6-BA), and partial sufficient irrigation after a uniform deficit irrigation (PR for without 6-BA, PRT for with 6-BA). Sufficient irrigation without 6-BA addition was taken as the control (CK). In all treatments, the concentration of 6-BA was 10 mg/L. For each treatment, we measured the physiological traits of the crop. 【Result】 Compared with CK, PD significantly increased dry root weight on the irrigated side, dry weight of the above-ground parts and the leaf area, but it did not have a noticeable impact on dry root weight on the not-irrigated side; it increased the contents of zeatin (ZA), nitrate nitrogen (NO3-) and soluble protein (Cpr) in the leaves, xylem sap and roots on the irrigated side, but reduced the content of abscisic acid (ABA). PR significantly reduced the weight of dry roots on both sides, weight of dry aboveground parts and leaf area, as well as the contents of ZA, NO3- and Cpr in leaves, xylem sap and roots on both sides, but it increased the content of ABA. Compared with PD and PR, PDT and PRT increased dry weight of the roots on both sides, dry weight of shoots and the leaf areas, as well as the contents of ZA, NO3- and Cpr in the plant, but reduced ABA thereby facilitating compensatory growth of the crop. 【Conclusion】 Partial water deficit irrigation followed a sufficient uniform irrigation is optimal for maize seedling growth, and combined with praying 6-BA, it can further boost compensatory growth of the crop.
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