HOW DOES WATER DEFICIT AFFECT GLADIOLUS GROWTH AND DEVELOPMENT?

ABSTRACT

The growing demand for gladiolus, especially at peaks of consumption, requires efficient scheduled production and good quality of floral stems. The objective of this study was to understand how water deficit affects the growth and development of gladiolus and, consequently, the quality of the floral stems produced. Plant development, quantitative parameters of the floral stems, and dry mass partitioning were evaluated in two field experiments with four gladiolus cultivars, with and without irrigation. The development cycle was longer in the non-irrigated treatment, whereas its duration under no water deficit was similar to that predicted by PhenoGlad, which is a gladiolus phenology model. As PhenoGlad predicts gladiolus development only for scenarios without water deficit, the inclusion of a water-stress submodel in the model would allow its application to any water supply scenario and help decision makers and farmers to plan gladiolus production more accurately. Water deficit also reduced gladiolus growth and flower stem size, but did not affect dry mass partitioning. As the development and quality of the floral stems of gladiolus were negatively affected by water stress, irrigation is essential for producing high-quality gladiolus floral stems and enabling production planning for peaks of consumption.

KEYWORDS
Irrigation; schedule production; floral stem quality; Gladiolus × grandiflorus Hort