Maximize Growth and Productivity of Rice by Using N2-Fixing Anabaena oryzae and Spirulina platensis Extract

Abstract

This study highlights the role of both inoculation with N2-Fixing cyanobacterium Anabaena oryzae and spraying with cyanobacterium Spirulina platensis extract and their combinations on growth and productivity of the two rice varieties (Sakha108 and Giza178) under different doses of nitrogen fertilizers. The experiment was laid out in a split - plot design with four replications; the two rice varieties were located in the main plots and fertilizer treatments were placed in the sub-plots. Chlorophyll content of flag leaf, plant height, number of panicle/m2 and panicle length, number of filled grain/panicle, one thousand grain weight, straw and grain yields (t/ha) were measured. Bioactive compounds and amino acid production of Spirulina were determined by GC–MC and amino acid analyzer, respectively. The results show Spirulina extract contains eighteen amino acid and several bioactive molecules and application of mixture Anabaena oryzae and Spirulina platensis extract with 75% recommended dose of nitrogen or recommended dose of N fertilizer gave nearly the highest value of growth characters, grain yield and yield components compared with other treatments in both seasons. This study describes the role of Anabaena oryzae and spraying with Spirulina platensis extract through plant-microbe interactions and the effect of this reaction on the growth and productivity of rice crop.