Bell pepper yield and soil properties during conversion from conventional to organic production in Indian Himalayas.
A conversion period of at least two years is required for annual crops before produce may be certified as organically grown. There is a need for better understanding of the various management options for transitioning from conventional to organic production. The purpose of this study was to evaluate the effects of three organic amendments on growth and yield of bell pepper (Capsicum annuum L.), the benefit:cost ratio, soil fertility and enzymatic activities during conversion to organic production. The organic amendments were composted farmyard manure (FYMC), vermicompost (VC) and poultry manure (PM) along with biofertilizers [Azotobacter + Phosphorus solubilizing Bacteria (Pseudomonas striata)]. The bell pepper yield under organic management was markedly lower (33-53% and 18-40% less in first and second year of conversion, respectively) compared with conventional practice (FYMC 10 Mg ha-1 + NPK - 100:22:41.5 kg ha-1). Composted FYM 20 Mg ha-1 + biofertilizers (BF), and combined application of three organic amendments (FYMC 10 Mg ha-1 + PM and VC each 1.5 Mg ha-1 + BF) produced similar but significantly higher yield (27.9 and 26.1 Mg ha-1, respectively) of bell pepper compared with other organic amendment treatments. Composted FYM 20 Mg ha-1 + BF and combined application of three organic amendments greatly lowered soil bulk density (1.15-1.17 Mg m-3), and enhanced pH (7.1) and oxidizable organic carbon (1.2-1.3%) of soil compared with conventional practice and unamended control after a two-year transition period. However, the N, P and K levels were highest in the plots under conventional practice. Plots amended with FYMC 20 Mg ha-1 + BF had higher soil microbial activities of dehydrogenase, acid phosphatase and β-glucosidase compared with other treatments. However, the urease activity was greater in the plots under conventional practice. Among the treatments involving organic amendments alone, FYMC 20 Mg ha-1 + BF gave the highest gross margin (US $ 8237.5 ha-1) compared to other treatments. We conclude that FYMC 20 Mg ha-1 + BF was found more suitable for enhancing bell pepper growth and yield, through improved soil properties, during conversion to organic production.Open preprint
This article is a preprint and has not been peer reviewed