Preface Over exploitation of natural resources and excessive chemicalization of agriculture in the past few decades, have led to poor sustainability of vegetable production. Over dependency and indiscriminate use of chemicals and fertilizers have resulted in the problems of pest/diseases resurgence, secondary pest out breaks, development of pest resistance, decimation of natural enemies on one hand and disturbances to environment and health hazards through residues in food chain on the other hand. These side effects have raised public concern about the safety of use of pesticides. Integrated Pests Management (IPM) is one such environment friendly approach to pest management that relies on combination of common sense approaches and fits in to the concept of sustainable agriculture. IPM incorporates ecological and socio-economic factors in to agricultural ecosystem and decision making process and addresses public concern about environmental quality and food safety. Today IPM is considered to be the spring board to sustainable management of vegetable crops and form a focus of the present book. Diseases are the most limiting biotic factors in vegetable production. There has been a demand from progressive vegetable growers, plant protection officials, subject matter specialist and research students for long for a comprehensive colour compendium on vegetable diseases. In the absence of such a type of book, identification is still difficult by the personnel engaged in different activities of vegetable production. With this view, “Diseases of vegetable crops and their integrated management” is prepared. This book has been prepared to assist clear diagnosis of the diseases and planning of integrated management strategies for sustainability of vegetable production. On the basis of several experiments conducted on vegetable crops for last several years and experience gained on vegetable pathology, integrated management practices have been encapsulated in this book. We hope that this book will serve all needy personnel whose ever is directly or indirectly related to vegetable production.

1. Damping-off Pathogen Pythium aphanidermatum (Edson.) Fitz. P. debaryanum                   Rhizoctonia solani Kuhn. Fusarium spp. Sclerotium spp. Symptoms Damping-off of onion seedlings occurs in two stages:     (i)    Pre emergence (ii)    Post emergence In pre emergence stage, plumules are killed before they reach the soil surface. They may be infected, killed even before the hypocotyls have broken the seed coat.

Vegetables Peas 1. Rust Pathogen Uromyces fabae (Pers.) de Bary Symptoms  The fungus produces characteristics rust pustules on the host. Pustules are mostly found on the leaf blade, though often they may be found on the petiole and stem of pea plants. The sori are small, roundish, open, and powdery as well as brown coloured. In severe infections, the leaf may wither, resulting in considerable damage to the crop. As the plants near maturity, the fungus produces the telial stage on the host.

Tomato 1. Damping off Pathogen Pythium aphanidermatum Fusarium spp. Sclerotium spp. Symptoms Damping off is the most important disease of tomato. Several seed and soil borne fungi can kill before the tender redical and plumule establish in the nursery bed. The pre emergence damping off and seed rotting is the usual cause of poor seedling stand. This type of damping off causes hidden loss but the post emergence damping off is more serious problem. Seedlings get infected near the soil line (collar region) after emergence and give wire stem symptoms. The tissue become soft, water soaked and weak causing the seedlings fall over and later on they die. The entire action is so fast that leaves remain green but they are unable to stand further.

Cauliflower, Cabbage and Knol khol 1. Leaf spot Pathogen Alternaria brassicae (Berk.) Sacc. Symptoms Alternaria leaf spot usually appear in early stage in cauliflower while at later stage symptoms in cabbage appear as circular light brown spot in leaves. Concentric rings are clearly visible on the spots. In older plants on leaves, petioles and stem, brown to black circular to slightly elongated spots appear.

1. Damping off Pathogen Pythium spp Phytophthora spp Fusarium spp Sclerotium spp Symptoms It is a term used to describe the damage caused by various fungi to the seed and emerging seedling in the reduced plant stand and sometimes it is so serious that  resowing becomes inevitable. Major symptoms are the failure of the seedlings decay or sudden death of the emerged seedlings roots and lower stems of emerged seedlings become soft and watery and may be reddish brown in colour.

Okra/Ladies finger/Bhindi 1. Leaf blight/Spot Pathogen Cercospora abelmoschi Ell. & Ev. Symptoms The fungus grows as shooty to dark olivaceous, ectoparasite covering entire leaf lamina. Pathogen initiates as small isolated fungal growth on lower side of leaf but very soon it spreads on both sides. Pathogen reduces severely the photosynthesis area. Infected leaves fall down very quickly after dropping and rolling. It causes severe loss in seed production crop as well as in the late sown crops.

Annexures Table: List of vegetable crops, their diseases and causal organisms