Genotype variations in biomass production and nutrient removal pattern in gladiolus raised from cormels

Abstract

The present study was conducted at ICAR-IIHR, Bengaluru, India during 2018-2019 to quantify resource use efficiency in 11 genotypes of gladiolus propagated through cormels based on growth, biomass partitioning and nutrient removal pattern. Growth and yield parameters differed significantly among genotypes. The leaf number was significantly higher in Arka Shobha (9.67) and Arka Manorama (9.00) than other genotypes (6.33-8.67). The spike length was higher in Arka Naveen (102.9 cm) and lesser in Arka Kumkum (66.2 cm). The pattern of biomass partitioning indicated that below ground biomass (corm) accounted for 71.5% of total biomass (3990 kg ha-1), while above ground biomass (leaf and spike) was 28.5% of total biomass (1137 kg ha-1). In gladiolus genotypes, the nutrient profile indicated that the accumulation of N was higher in corms followed by leaves and spikes. The accumulation of P (0.13-0.14%), Mn (29.8-43.5 mg kg-1), Zn (15.3-23.4 mg kg-1) and Cu (5.2-6.0 mg kg-1) was similar. Spikes accumulated higher K and Mg than leaves and corms. The accumulation of Ca was more in leaves (2.39%) followed by flower stalks (1.95 %). The average Fe concentration (mg kg-1) was more in corms (293) followed by leaves (269) and flower stalks (160). The average nutrient removal in genotypes was quantified at 122 kg N, 10.8 kg P and 71.7 kg K per ha per crop. The nutrient demand (g ha-1) of Fe was more (1062.4) than Mn (152.5), Zn (23.8) and Cu (23.0). The data implies that gladiolus is a heavy feeder of N and K. Nutrient removal of K and Fe influenced the biomass production with high degree of variability (Y =-541.858 + 24.097 Kuptake + 1.405 Feuptake R2=0.995). The present study gives scope for precision nutrient use by avoiding blanket recommendations.