Effect of Biofertilizer ( Aspergillus niger ) on potassium availability in some calcareous soils in Northern of Iraq


Three different soil textures from Mosul city in northern Iraq ( clay , Sandy loam and Loam sand ) were collected and classified as calciorthids ,to study the effect of biofertilizers (Aspergillus niger ) on natural release of potassium. The soils were inculcated and incubated at constant temperature 28°C during four weeks at filed capacity , by using complete randomize block designe. The results showed that biofertilizer gave a significant increase in available potassium ( 675, 140 and 124% ) for (clay , S.L and Loam sand Textures ) respectively. Also clay texture give a good reserve and high ability in potassium release and K. suppling comparing with coarse texture. Also the results showed that increasing in time of incubation during four weeks caused an increasing of exchanged potassium release .


Biofertilizer, Iraq