Abstract
Medicinal plants constitute an important group of horticultural crops and
many non-tuberous medicinal plants viz., aloe vera (Aloe vera), basil (Ocimum
sanctum), mentha (Mentha arvensis), noni (Morinda citrifolia), isabgol (Plantago
ovata), mulethi or liquorice (Glycyrrhiza glabra), rosa grass (Cymbopogan nardus),
etc. are currently used to prepare stimulants, tonics, carminatives, and expectorants.
Various biotic and abiotic stresses affect the production of these medicinal crops.
Among the biotic stresses, diseases caused by fungi, bacteria, viruses, and nematodes
are major constraints. Diseases of aloe vera (such as anthracnose, dry rot, rust, soft rot),
noni (dry rot, leaf blight, soft rot, root-knot), basil (anthracnose, leaf spot. powdery
mildew, wilt), mentha (leaf spot, root-rot, rust, wilt), isabgol (Downey mildew, wilt),
rosa grass (leaf blight. Red leaf spot), liquorice (leaf spot, root-rot) pose a serious risk
to the successful cultivation of these medicinal plants. The economically significant
diseases of non-tuberous medicinal plants are discussed and the relevant information is
described in this chapter.