An integrated approach to primary and secondary hardening of banana var. Grand Naine

Abstract

For improving banana productivity, virus-indexed Grand Naine plantlets were used for primary and secondary hardening. Among nine combinations of bio-fertilizers (including VAM) used, GNP₂V₁ medium comprising of peat fortified with nitrogen fixing and phosphate solubilizing microbes (each 1 g/plantlet) and VAM (2 g/plantlet) emerged as the optimal growth medium for primary hardening on the basis of statistically significant 98.9% survival, besides corroborating optimal morphological features (viz. root length, number of primary roots, % VAM colonization, height, girth, number of leaves, leaf area and chlorophyll content) at the end of primary hardening. For secondary hardening, among four combinations of bio-fertilizers and VAM used in conjunction with soil, press mud cake (PMC) and vermi-compost (VC), SNP₂V₁ medium comprising of soil, PMC and VC in a ratio of 1:1:1 (v/v/v) emerged as the optimal growth medium on the basis of statistically significant 97% survival, corroborated by optimal morphological features as above, along with uptake of macro- and micro-nutrients. The positive feedback by several monitoring parameters have left no doubt about the integrated outcome at the end of primary and secondary hardening.