The impact of different biochars on Stemphylium leaf blight (SLB) suppression and productivity of onion (Allium cepa L.) oleh Muhammad Arif, Muhammad Sarmad Fawaz, Ali Tan Kee Zuan, Rahmat Ullah Shah, Rehmat Ullah, Ahmed M. Elshehawi, Abdullah M. Al-Sadi, Muhammad Ihsan Ullah, Mehmet Ertuğrul Güldür, Saqer S. Alotaibi, Muhammad Ifnan Khan, Ansar Hussain