This study was carried out in wholesale markets in Governorates of Aden, Taiz , Sana’a, Hudaida and Hadramout during the period 1998 - 2002. Examination of samples taken from the wholesale markets showed that there exist numerous damaging insects such as tomatoes and potatoes tubers. The study identified several fungal diseases causing damages to some horticultural crops in wholesale markets such as Aspergillus niger. The main bacterial disease identified was Erwinia carotovora on potatoes, tomatoes, onions and grapes. Other crop damaging diseases of physiological origin like potatoes greening, tomatoes blossom and rot were observed. Precentage of insects and diseases infections varied from crop to another and from market to another.

Key Words :Post Harvest, vegetables, fruits, Insects, Diseases, marketing, Wholesale Markets