Assessing resource use in gerbera genotypes for precision nutrient use in protected condition

Abstract

The present study was conducted in the existing germplasm block of gerbera under protected condition at ICAR-IIHR, Bengaluru, India during 2017–2019 to obtain comprehensive information on biomass partitioning, nutrient uptake pattern and flower yields in different genotypes for precision use of critical inputs. The number of leaves (187.6–353.2 m⁻²yr⁻¹) and flower stalks (166.9–274.5 m⁻²yr⁻¹) varied significantly among genotypes. Specific leaf area (SLA) was similar among Balance, Stanza, Arka Aswha and Terra Kalina cultivars (0.150–0.156 cm² mg⁻¹). Strong positive influence of SLA on number of flower stalks was evident from the significant correlation (r = –0.774). Significant positive correlations among number of flower stalks and leaves, leaf area and SLA substantiate the flower yield pattern in gerbera. Optimum leaf number per plant was estimated at 18.6, while optimum range was quantified at 14.1 to 22.4. In gerbera genotypes, the partitioning of total aboveground dry biomass to leaves and flower stalks was 46–61% and 39–54%, respectively. The average nutrient removal was quantified at 32.8 g N, 7.3 g P, 78.7 g K, 24.7 g Ca and 4.1 g Mg m⁻²yr⁻¹ and the uptake of macronutrients was in the order of K > N > Ca > P > Mg. The order of micronutrient removal (g m⁻²yr⁻¹) was Fe (0.2), Zn (0.08), Mn (0.06) and Cu (0.03). The soil fertility status at uniform management was above optimum. It is clear that leaf number, biomass partitioning and nutrient removal pattern had direct impact on flower stalk yields of gerbera.

Keywords:

• biomass partitioning
• genotypes
• gerbera
• nutrient index
• nutrient removal
• polyhouse