Cultivation under photoselective shade nets alters the morphology and physiology of Begonia Megawatt varieties

Light intensity and quality playa key role in plant growth and development. Photoselective shade nets control light quality, temperature, and humidity, improving plant growth, color, and flowering, and resulting in better commercial quality of ornamental plants. This study aimed to assess the growth and quality parameters of two varieties of Begonia Megawatt plants cultivated under photoselective shade nets. The experiment followed a randomized block design with subdivided plots. The plots included blue, red, and black shade nets and a control group without shading. The subplots were Begonia Megawatt varieties 'Pink Green' and 'Red Bronze'. We evaluated temperature, relative humidity, illuminance level, plant growth and flowering parameters, leaf chlorophyll and flavonoids, and colorimetric indices oftepals. Begonia 'Red Bronze' had greater height and root mass, while 'Pink Green' had more inflorescences. The blue photoselective net increased leaf number by 14%, and the red photoselective net enhanced inflorescence dry mass by 30.6%. The use of photoselective shade nets contributed to optimal conditionsfor plant growth, reducing light intensity by 28% and lowering maximum temperatures, resulting in potted plants with improved commercial quality. The use of blue and red shade nets is recommended for potted begonias.