THE EFFECT OF COATING BACTERIA-INOCULATED SEED WITH CHITOSAN AND SODIUM ALGINATE BIOPOLYMERS ON SOME GROWTH PARAMETERS OF BEAN PLANT

In recent years, microbial fertilizers have been suggested as alternatives to reduce the negative impacts of agricultural activities. However, the application of microbial fertilizers in agriculture is restricted due to their sensitivity. The purpose of this study is to avoid or eliminate these limitations by inoculating bean plant seeds with rhizobium bacteria and then coating them with chitosan and sodium alginate biopolymers to protect the viability of the bacteria for three months. The coating of the bacteria provides a safe environment for their growth, increases their sustainability, and can provide protection. To achieve this objective, seeds of the Yunus 90 bean cultivar were inoculated with rhizobium bacteria in a liquid formulation (1x108 CFU) after surface sterilization. After inoculation, chitosan and sodium alginate biopolymers at a concentration of 1% were used to coat the bacteria. After inoculation, the seeds coated with biopolymers were dried in a dark place for 1-2 hours, then packed and stored for 90 days. After 3 months, a controlled greenhouse experiment was conducted in which the seeds were planted in pots containing sterile sand and perlite. At the same time, biopolymer-coated bean seeds inoculated with bacteria are grown as a control. As a result, different effects of coatings with the biopolymers chitosan and sodium alginate on bacteria-inoculated seeds of a bean plant were shown, and these differences were found to be statistically significant (p<0.01). It was found that the coating with the biopolymer sodium alginate was more effective than chitosan in maintaining bacterial survival and increasing some yield components compared to the treated control sample. Bean seeds, after being inoculated with rhizobium bacteria and coated with biopolymers, the bacteria may maintain their shelf life by around 50% when considering the sensitivity of traditional microbial fertilizers applications.