Response of Cryptocoryne zaidiana Ipor & Tawan (Araceae) to shading and water depth

Abstract

Study on the responses of Cryptocoryne zaidiana Ipor & Tawan (Araceae) to shading and water depth was conducted. Vegetative characteristics and biomass partitioning (plant height, total leaf number and total dry weight), leaf weight ratio (LWR), petiole weight ratio (PWR), root weight ratio (RWR), rhizome weight ratio (RhWR), leaf area ratio (LAR) and specific leaf area (SLA)) of C. zaidiana grown in natural habitat at Sg. Mering varied between quadrates. Plants under 50% shading produced significantly more leaves, RWR and RhWR than those at 75% shading and under tree canopy. Plants under 75% shading produce the least number leaves. Plants placed at 10 cm water depth showed significantly higher values of LWR, PWR, RWR, LAR and SLA as compared to plants at 0 cm water depth. However, at 30 cm water depth, plants significantly increased their height as compared to the other two water depth regimes. Plants being placed under 75% shading and 10 cm water depth had the highest dry matter production (DMP) while highest NAR was recorded by plants cultivated under 50% shading and 0 cm water depth. Satisfactory sprouting of rhizome-cutting was recorded by 5-node cuttings viz. 38 plants out of 50 rhizomes. The lowest maximal quantum yield was recorded at 50% shading and it was significantly different between both tree canopy shading and 75% shading. Plants grown under 50% shading regime and 0 cm water depth resulted in higher electron transport rate (ETR) value at 640 μmol quanta m-2s-1.