MOLECULAR DIAGNOSIS AND DETERMINE EFFECT OF CULTIVARS, DATES OF PLANTING AND GEOGRAPHIC LOCATIONS IN PERCENTAGE AND SEVERITY INFECTION OF BIGEMINIVIRIDAE TOMATO YELLOW LEAF CURL VIRUS (TYLCV) ON TOMATO IN FIVE DESERT AREAS OF IRAQ

Abstract

A survey of Bigeminiviridae Tomato yellow leaf curl virus (TYLCV) in five desert areas of Iraq (Basra, Kut, Najaf, Baghdad and Saladin) to molecularly diagnoses and determine the proportion and severity of the virus on common and hybrid tomato varieties, as well as dates of appearance of the virus. Bigeminiviridae Tomato yellow leaf curl virus (TYLCV) was molecularly diagnosed for the first time in Saladin by Polymerase Chain Reaction (PCR), as well as the symptoms caused by virus on host and transport by Bemisia tabaci . the result showed the efficiency of molecular diagnosis in very precise detection of the virus ,where a virus appeared for each primer used in molecular diagnosis .Two primers were used in the diagnosis of the virus of different sizes which indicates the presence of virus in Plants taken from fields and artificial infection plants . The highest increase in percentage and severity of infection in province of Basra, which amounted to 96, 4 and 30,3 for normal and hybrid varieties at beginning of August respectively, and amounted to 4,55 and 5,2 at beginning of October respectively, and was lowest in the province of Saladin . The study showed that the date of cultivation at beginning of August was highest in proportion and severity of injury compared to second date of cultivation at beginning of October.