kiva ku bijanjaalo ebingi eby'omu buvanjuba bwa afrika okulwanyisa obuwuka obuyitibwa bacterial wilt black sigatoka nematodes n'okulongoosa ebiriisa mu vitamiini a n'ebijanjaalo eby'ekyuma okunoonyereza mu kasooli okulwanyisa akawuka ka cassava brown streak virus ne cassava mosaic virus