Types of shelter and covering materials influencing growth, pigment, and nutrient concentrations of baby rubber plants (Peperomia obtusifolia)

Abstract

The cultivation of ornamental plants under different types of shelter and covering materials which reduce light intensity, resulting in morphological and physiological changes, needs to be evaluated before any large-scale use of such types of shelter covers. Baby rubber plants were grown in pots filled with peat under four different shelters and covering materials as follows: MG (multitunnel greenhouse with thermo-reflective aluminised screen), BG (buried solar greenhouse with thermo-reflective aluminised screen), NH (net house covered only with antipest mesh) and NH-AS (net house with antipest mesh and thermo-reflective aluminised screen). At the end of the experiment, the growth parameters and color of leaves, as well as photosynthetic and nutritional parameters, were assessed for each treatment. Baby rubber plants grown under NH-AS showed the highest values for growth parameters. The absence of shading in a net house may result in photoinhibition, reducing the growth and increasing the values of red (R) and blue (B) in leaves, which may be related to the increase of anthocyanin synthesis. The low level of radiation intercepted in the multitunnel and the buried greenhouse increased chlorophyll, N and P leaf concentration, while for K concentration, there was no clear trend and Na and Cl leaf concentration were similar under the different types of shelter. We concluded that the production of baby rubber plants under net house with antipest mesh and thermo-reflective aluminised screen is the best option to maximise the market value of baby rubber plants.