Influence of microflora associated with earthworm (Eudrilus eugeniae kinberg) and vermicompost on growth and performance of chilli. (capsicum annuum L.)

Abstract

The present investigation on 'Influence of microflora associated with earthworm (Eudrilus eugeniae Kinberg) and vermicompost on growth and performance of chilli (Capsicum annuum L.) was done at College of Agriculture, Vellayani during 1997-99 as part of a Science, Technology and Environment Department (Government of Kerala) funded research project. Among the surface microflora of Eudrilus eugeniae, the total number of bacteria, fungi and actinomycetes were maximum on 45 day of compost formation. However, the number of nitrogen fixing bacteria was more on 60 day. Similarly, in the case of gut micro flora, the total number of bacteria and fungi were maximum on 45 day of composting. However, the number of actinomycetes was more on 30 day. Nitrogen fixing bacteria could be isolated only on 15 day. In the vermicompost, the total number: of bacteria fungi and actinomycetes were maximum on 30,45 and 60 day respectively. The number of phosphate solubilizing bacteria and nitrogen fixing bacteria were more on 15 and 30 day of sampling. However, soilborne pathogens such as Pseudomonas solanacearum, Pythium spp. and Phytophthora spp. were absent.

There were significant differences in the growth rate of various isolates of nitrogen fixing bacteria in Jensen's nitrogen free broth. The mean optical density for isolate 3 was significantly higher than rest of isolates. The nitrogen fixing ability of this isolate was also higher. The isolate 3 was selected for enrichment of vermicompost. Based on various morphological and physiological characters, this isolate was tentatively identified as Azotobacter sp. Among the different isolates of phosphate solubilizing bacteria, the isolate 1 which showed maximum solubilization of tricalcium phosphate in modified Pikovskaya's broth was selected for enrichment of vermicompost. Based on the various morphological and physiological characters, the isolate 1 was tentatively identified as Pseudomonas sp. In the study on the enrichment of vermicompost with nitrogen fixing bacteria on growth of chilli, the shoot fresh and dry weights were significantly high in the treatment combination receiving vermicompost enriched with Azotobacter sp. along with 50 per cent nitrogen (N3P1K+VN) when compared to the control treatment. The per plant yield was significantly high in the treatment combination with 100 per cent nitrogen and vermicompost enriched with Azotobacter sp. (NIP1K+VN) followed by that receiving 75 per cent nitrogen and vermicompost enriched with Azotobacter sp. (N2P1K +VN).

In the study on the use of vermicompost enriched with phosphate solubilizing bacteria, there were significantly earlier onset of flowering and significantly higher number of fruits formed per plant in the treatment combination of 100 per cent phosphorus along with vermicompost enriched with Pseudomonas sp. There were no significant differences between treatments in the keeping quality of chilli harvested from treatments with enriched vermicompost. III the interaction study between Eudrilus eugeniae or Megascolex sp. and Pythium aphanidermatum, there was 100 per cent seedling mortality in treatments such as. POP(F)+P and POP(V)+P where the application of Pythium aphanidermatum was coupled with surface injury in the collar region of seedlings. But in the absence of such an induced injury, there was no incidence of damping off. However, in these treatments the plant growth was generally poor in height, fresh and dry weight of roots. At the same time, the plant growth was better in treatments without pathogen inoculation. The number of branches formed was significantly high in POP(F)+E and POP(V)+E treatments where Eudrilus eugeniae was applied when compared to that of the control treatment. The treatment with vermicompost alone (POP (V» recorded significantly earlier onset of flowering. The number of fruits formed per plant

and per plant yield were significantly higher in the treatment with farm yard manure and Eudrilus eugeniae (POP (F)+E) compared to the control. Significant differences between treatments were observed in the onset of flowering, number of fruits formed and in the per plant yield of chilli due to the combined application of Megascolex sp. and Pythium aphanidermatum. Flower initiation was earlier as well as the number of fruits formed were also significantly high in the treatments with vermicompost either alone (POP (V» or in combination with Megascolex sp. (POP(V)+M). The treatment with vermicompost alone recorded the highest per plant yield. There were no significant differences between treatments in the keeping quality of chilli harvested from treatments with or without the application of either Eudrilus or Megascolex sp. and Pythium aphanidermatum.