Conditioning effects of biodegradable superabsorbent polymer and vermi-products on media properties and growth of gerbera

Abstract

With the objective of identifying an ecologically sustainable substrate for commercial gerbera production, we conducted an experiment to assess the effects of super absorbent polymer and organic vermi-products on the physico-chemical properties of the growing media, and plant growth and flower yield in gerbera cv. Yosemite. CPV (Cocopeat: Perlite: Vermiculite) and soil amended with vermicompost (VC, 20%), Pusa hydrogel (PHG, 0.25%) and horn bio-manure (HBM, 1%) had significant positive effects on growth and flowering of gerbera. The lowest (0.29 ± 0.02 g cm−3) bulk density was recorded in CPV+PHG+HBM while the maximum (59.75 ± 0.63%) water holding capacity was observed in CPV+PHG+VC substrate. The maximum electric conductivity (0.99 ± 0.06 dSm−1) and pH (7.90 ± 0.04) were recorded in Soil+PHG+VC. Plants grown on CPV+PHG+VC media and sprayed with 20% of vermiwash produced the highest number of leaves during the entire period (31 ± 0.58), maximum leaf length (30.18 ± 0.18 cm) and width (8.30 ± 0.16 cm), maximum number of primary roots (42 ± 1.53), highest flowers per plant (19.67 ± 0.33), stalk length (41.08 ± 0.10 cm) and flower head diameter (10.11 ± 0.03 cm). Flowers produced on this medium also had an extended attractive appearance (20.33 ± 0.33 days) and longer vase life (14.33 ± 0.33 days). Water requirement of gerbera (litre/crop season) on CPV+PHG+VC medium, with or without Vermiwash spray was also considerably lower than other treatments. Overall results suggest that CPV amended with PHG and VC coupled with Vermiwash spray provide congenial conditions for gerbera plant growth and flower production while also simultaneously reducing irrigation water use considerably.