Variability of Fusarium oxysporum f. sp. lycopersici from different altitudes in East Java, Indonesia

Fusarium wilt disease attacks the tomato plants, and Solanaceae plants with losses can reach 90 %. Thus, this disease was tough to control. The morphology and pathogenicity variation caused failure disease control. Both variations could be affected by the altitude of the planting site. Therefore, it also required special handling of management as well. The specific objectives of this study to investigate the Fusarium isolate from different altitude response of physical properties (acid-base pH, low-high temperature, and fungicides of other active ingredients) and growth rate of Fusarium. All Fusarium sp. were isolated from the leaves, soil, roots, and stem of infected tomato plants. Before a series of tests were carried out, all of the isolates were tested for pathogenicity, then tested for the influence of abiotic factors. This study obtained four isolates from high altitude, four isolates from medium altitude, and five lowland isolates. In morphological observations, there were striking differences in colony color and growth rate among isolates on several media and pathogenicity tests. Each isolate had different pathogenicity, although from the same location but other parts of the plant. Knowing the characteristic morphology and Fusarium sp. response of the three areas can be used as references in controlling.