Preparation of Biofertilizer from Azospirillum brasilense Bacteria and test its Impact on Growth and Yield of Wheat Triticum aestivum L. in Gypsiferous Soil

Abstract

After confirm the bacterial strain that it is belong to Azospirillum brasilens and test the efficiency on nitrogen fixation , Indolic Acetic Acid (IAA) Hormone production , this strain was grown in slants and transferred to liquid broth in the rotary shaker to prepare mother (starter) culture which contain 5 x 10⁹ CFU.ml^-1  and then mixed starter culture with two types of carriers ( powder of date palm nucleus and powder of olive nucleus).

After that, field experiment was conducted in gypsifores soil ( Typiccalcigypsids) to study the efficiency of this biofertilizer on promoting the wheat growth and yield at three levels of nitrogen (0 , 50% , 100%) of fertilizer recommendation .

Results showed that the biofertilizer which was added alone either with date palm nucleus powder or with olive nucleus caused significant increases in plant high , dry weight of vegetative part , roots dry weight after 60 days from germination and the dry weight of straw and grain yield compare with control treatment with percentage increases of 22.68 , 92.84 , 171.01 , 75.5% for biofertilizer which held on date palm nucleus powder and  21.2 , 59.46 , 134.7 , 40.01 and 37.11% respectively . Also the results refered to not significant differences between two carriers. The result also appear that the beneficial effect of biofertilization continuous with increase of nitrogen levels , the treatment ( biofertilize with date palm nucleus powder + 100% nitrogen fertilizers) gave highest values in straw and grain yield where is ( 5.41 and 4.30 ) ton. ha^-1 in compare with the same treatment which take half of fertilizers recommendation which gave (5.33 and 3.86) ton.ha^-1. Also the result showed significant effect of bio-fertilization on the number of Azospirillum bacteria , ( 32 x 10⁴ and 30 x 10⁴ )CFU . gm^-1soil for bio-fertilizer which was carried on date palm nucleus powder and olive nucleus powder, respectively in compare with control which gave 13.33 x 10⁴ CFU. gm^-1soil.