Comparative Growth of Red Chrysanthemum Plantlets in Micropropagation and Microponic Systems

<b>Background and Objective:</b> <i>Chrysanthemum</i> is one of the most important ornamental plants worldwide, yet conventional propagation methods remain inefficient; therefore, microponics (a system integrating micropropagation with hydroponics) offers strong potential for producing high-quality planting materials at scale. This study evaluates the efficiency of microponic and micropropagation systems for <i>in vitro</i> propagation of the red cultivar of <i>Chrysanthemum</i>×<i>morifolium</i>, focusing on optimizing medium composition, plant growth regulator levels, medium volume and culture density and comparing plantlet performance during nursery acclimatization. <b>Materials and Methods:</b> <i>In vitro</i> shoots, measuring 1-1.5 cm in length and consisting of two nodes, were used as explants. Experiments were arranged in a completely randomized design with five replicates. Data were statistically analyzed using Analysis of Variance (ANOVA) with IRRISTAT 5.0, SPSS 20.0 and Microsoft Excel to identify the optimal culture conditions for each system and to compare growth parameters of plantlets during nursery conditions with treatment means compared by DMRT at the 5% significance level. <b>Results:</b> The optimal conditions for the microponic system were obtained using liquid 1/2MS medium supplemented with 0.1 ppm naphthaleneacetic acid (NAA), with a medium volume of 20 mL and a culture density of nine shoots per vessel. Under these conditions, plantlets exhibited the highest shoot height (2.03 cm), fresh mass (0.17 g), 100% root initiation, 3.89 roots per explant (0.64 cm in length) and 4.26 leaves after two weeks of culture. In contrast, the optimal micropropagation medium was solid MS supplemented with 0.3 ppm NAA, 0.5 g/L activated charcoal (AC), 30 g/L sucrose, with the same culture density that used in the microponic system. Plantlets in this system reached a shoot height of 3.14 cm, a fresh mass of 0.20 g, 100% root initiation, 4.87 roots (3.44 cm in length) and five leaves. After 90 days in the nursery, micropropagated plantlets exhibited greater height, a higher number of leaves and earlier flowering, whereas microponic-derived plantlets developed larger leaves, thicker shoots and wider canopy diameters. <b>Conclusion:</b> The micropropagation system provided optimal conditions for <i>in vitro</i> shoot growth and promoted earlier flowering, while the microponic system improved acclimatization and post-transplant performance of red cultivar of <i>Chrysanthemum</i>×<i>morifolium</i> plantlets.