An Advancment in Nitrogen Fixation by Endophyte

Now a days, a lot of new technologies have been implied to boost up N availability such as use of N fixing microorganisms or use of organic acids. But little attention has been given to the use of endophytes to enhance the N availability and nitrogen losses. Endophytes are micro-organisms that live within the tissues of a plant, without causing symptoms of disease. Endophytes can be used to develop bio-fertilizer that releases nitrogen slowly. Therefore, now researchers are focusing on the use of endophytic bacterial impregnation to prolong the availability of N in soil to replenish the pool of N to meet the plant requirements.

Controlled Release Fertilizers:  

Controlled-release fertilizers are being developed to improve nutrient use efficiency while reducing environmental hazards. It has also been reported that greater fruit yield was obtained using controlled-release fertilizers compared with water soluble fertilizers. These types of fertilizers can provide many benefits to agriculture, such as higher fertilizer use efficiency, reduced nutrient losses via fixation, leaching and denitrification and reduction of soil chemical processes that decrease the availability of nutrients. Therefore impregnation of commercial urea with endophytic bacteria could be effective to pro log the availability of nitrogen to plants in soil.

Experiments at Endophytic Efficiency:  

To investigate the efficiency of endophytic bacterial impregnated urea, pot trial was conducted at wire house of Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad. Two bacterial strains FD17 and PSJN were impregnated on urea. There were 8 treatments with 3 replications of each. The data regarding growth, yield and chemical parameters was obtained and analyzed statistically. Obtaining best results of T8 and preceding T5, it was concluded that endophytic bacterial impregnated urea showed maximum growth and yield as compared to other treatments. It was inferred that endophytes are helpful in prevention of nitrogen losses and enhance nitrogen use efficiency of plants and soil.

Results of study:  

Results of study indicated that wheat crop responded positively to the application of endophytic bacterial impregnated urea as compared to uncoated urea and control (no NPK was applied). Maximum plant heights were obtained from T5 (NPK + Seed inoculated both strains FD17 and PSJN) and T8 (Urea impregnated with strains FD17 and PSJN) Bacterial strain FD17 and PSJN coating on urea were found to be superior in most of the yield and growth parameters. Treatment (T8) having endophytic bacterial impregnated urea concentration improved the N concentration in shoot (2.61%) as compared to uncoated urea (T2) in which N concentration of shoot.  Application of endophytic bacterial impregnated urea improved the growth, yield and nitrogen use efficiency of crop. The maximum chlorophyll content was recorded in plants which received treatment T8 (PK + Urea impregnated with strains FD17 and PSJN) following T5 (NPK + Seed inoculated both strains FD17 and PSJN) and T7 (NPK + Seed inoculated both strains FD17 and PSJN) and these treatments produced 48, 47 and 45 spad value, respectively chlorophyll contents. Because endophytic bacterial impregnated urea converted it into more available form for a longer period as it slowed down the release of N. In T8 where endophytic bacterial impregnated urea with 100% recommended rate showed the highest percentage of nitrogen (as compare to uncoated urea) in grains. Overall experiment results suggested that coated urea as N source significantly increased most of the growth and yield parameters. Obtaining best results of T8 and preceding T5, it was concluded that endophytic bacterial impregnated urea showed maximum growth and yield as compared to other treatments. Endophytic bacterial impregnated urea has following benefits over un-impregnated urea:

•  Increased nutrients uptake and hence their use efficiency.
•  Performed better than uncoated N fertilizers.
•  Reduction in losses of N that resulted in more availability of N in soil.
•  Released the nutrients slowly and made it available throughout the growth period.
•  Reduced the fertilizer application rate due to higher uptake compared to uncoated urea.

CONCLUSION:

Keeping in view the above discussion, it can be concluded that use of slow release fertilizers more specifically endophytic bacterial coated fertilizers has significant effect on the growth and yield of crops and vegetables by controlling nutrient release rate and nutrient use efficiency.
By: Shoaib Aslam