Deficit irrigation and fertilizer rates affecting growth, flower quality and physiological changes in tuberous begonia grown in plant factory

Water deficit and plant nutrition deficiency affected growth and development of Begonia grown in greenhouse, therefore, the precision management of these factors is important for Begonia production in plant factory.
However, the report of an interaction between these two factors was too limited.
Therefore, the research was aimed to determine the effect of irrigation levels combined with fertilizer application on growth, flower quality and physiological changes in this plant.
Seedlings of tuberous begonia were grown in 6 inches of plastic pots in plant factory under average temperature at 20±2°C, 70% relative humidity and 60 µmol m^‑2 s^‑1 PPFD using high pressure sodium lamp.
The experimental designed was factorial in completely randomized design with two factors i.e., 1) three of irrigation levels at 25, 50, 100% ETc (30, 60 and 120 mL pot^‑1, respectively), and 2) four of fertilizer rates at 0, 1, 2 and 3 g pot^‑1 supplied once a month using the fertilizer with the equation 15N:15P₂O₅:15K₂O with 10 replications per treatment.
The results found that the irrigation at 100% ETc increased plant height, number of leaves plant^‑1, number of inflorescences plant^‑1 and stomatal conductance.
Water deficit at 25% ETc reduced plant growth and development and stimulated flowering.
Fertilizer rate at 1.0 g pot^‑1 was enough to increase plant height, number of leaves plant^‑1, number of florets inflorescence^‑1 and photosynthetic rate.
Increase of nitrogen, phosphorus and potassium concentration in leaf occurred when supplied with 2 and 3 g pot^‑1 but it did not increase growth and flower quality.
It concluded that the irrigation at 100% ETc with 1.0 g pot^‑1 of 15N:15P₂O₅:15K₂O fertilizer was an optimum level for growing tuberous begonia in plant factory.

IV Asian Horticultural Congress – AHC2023

C. Inkham, K. Panjama, S. Ruamrungsri

abiotic stress, control greenhouse, drought stress, plant nutrition, watering

https://doi.org/10.17660/ActaHortic.2024.1404.190