Plant growth-promoting bacteria as biofertilizer Fauzia Y. Hafeez, Sumera Yasmin, Dini Ariani, Mehboob-ur-Rahman, Yusuf Zafar and Kauser A. Malik Agron. Sustain. Dev., 26 2 (2006) 143-150 Published online: 08 July 2006 DOI: 10.1051/agro:2006007