MORPHOCHEMICAL CHANGES IN KATARIBHOGH RICE IN RESPONSE TO COTREATMENT OF UREA AND BACTERIAL CONSORTIA

Abstract

Endophytic bacteria are recognized as eco-friendly biofertilizer those have demonstrated the potential to enhance crop growth and yield. The mixture of multiple bacteria (bacterial consortia) enhanced more robust vegetative growth of plants than single endophytic bacteria. It has been suggested that plants require lower doses of fertilizers in response to exogenous application of bacterial consortia. Therefore, the aim of this study was to screen out the optimum concentration of nitrogen fertilizer with the endophytic bacterial consortia for the maximum yield of rice in field condition. To do this, different concentrations of urea fertilizers with a similar bacterial consortia were applied as foliar spray on Katarivogh rice. It is a popular aromatic rice cultivar cultivated in the Dinajpur district of Bangladesh. Here, we considered the recommended doses (RD) of urea as 100% urea. The experiment comprised of 13 treatments with 3 replications and followed a completely randomized plot design. A consortiam of isolated endophytic bacteria including Citrobacter sp. Strain HSTU-ABk15, Serrati asp strain HSTU–Abk35 and Acinetobacter sp. strain HSTU Azm16, was applied in the experiment. The treatments were T1 (no bacteria+no urea); T2 (only bacteria); T3 (bacteria+10% urea of RD); T4 (bacteria+20% urea of RD); T5 (bacteria+30% urea of RD); T6 (bacteria+40% urea of RD); T7 (bacteria+50% urea of RD); T8 (bacteria+60% urea of RD); T9 (bacteria+70% urea of RD); T10 (bacteria+80% urea of RD); T11 (bacteria+90% urea of RD); T12 (bacteria+100% urea), T13 (only 100% urea). To find out the effects of cotreatments of bacteria and urea fertilizer on rice growth and yield, we measured the related morphological and biochemical parameters. The observation of phenotypic traits showed that the highest number of tiller number (19.33), number of effective panicle (15), and yield of rice (11.63 Kg/decimal) were obtained in treatment T7 (bacteria+50%urea of RD) followed by T6, and T5. The total nitrogen content of leaf and grain were higher in treatment T7 than those of treatments T1, T2, T12 and T13. Altogether, the above results suggested that application of bacterial consortia with 40% to 50% urea of recommended dose produced maximum phenotypic growth similar to recommended doses of urea. The molecular mechanisms of how the bacterial consortia boosted up the plants growth with lower doses of urea remains to be elucidated.