Influence of growth retardants on growth and flowering of Crossandra (Crossandra infundibuliformis) under potted conditions

Abstract

The present research was carried out in crossandra at ICAR-DFR, Regional Station, Vemagiri, Kadiyam mandal. The experiment was carried out during 2021-22 (September-May). The experiment was laid out in Completely Randomised Design (CRD) with ten treatments of plant growth retardants viz., cycocel (500, 1000 1500 ppm), paclobutrazol (500, 1000, 1500 ppm) and maleic hydrazide (200, 600, 1000 ppm). The treatments were replicated thrice. The application of growth retardants led to significant differences in the various growth and flowering parameter among the treatments. Among the growth parameters, at 120 DAT, the maximum suppression in the plant height was observed with the application of paclobutrazol at 1500 ppm (37.92 cm) that was on par with the application of paclobutrazol at 1000 ppm (39.53 cm). The maximum plant height was recorded with control plants (56.46 cm). The foliar application of maleic hydrazide at 600 ppm recorded the maximum plant spread (57.14 cm), number of branches per plant (10.36) and leaf area (1714.42 cm2 ) as compared to other treatments. The chlorophyll content was recorded maximum with the spray application of paclobutrazol at 1500 ppm (190.08 SPAD units) as compared to control plants (160.18 SPAD units). Among the flowering attributes, the spray application of maleic hydrazide @ 600 ppm recorded the minimum number of days for first spike emergence (45.63 days), maximum number of spikes per plant (13.96), spike length (12.59 cm), flower yield per plant (43.09 g) 100 florets weight (5.18 g) and shelf life of florets (4.15 days) as compared to other treatments. From the results it can be concluded that foliar application of maleic hydrazide @ 600 ppm was proved to be superior in terms of growth and flowering parameters as compared to other plant growth retardants used in the study.