Plant Pathology Science

Najafiniya M. 2016. Management of citrus die-back disease. Plant Pathology Science 5(1):26-36.

Citrus trees are very important plants with high economic value and significant cultivation area in south of Iran. During the recent years, citrus die-back disease caused by Neofusicoccum mangiferae became one of the main treats for citrus production in tropical and sub-tropical regions of Iran. The symptoms of die- back disease are including wilting and declining of branches which start from the tip and then develop to down part of the trunk of infected tree, which sometimes has longitudinal cracks with gum exudation. Cortical layers of infected branches are sloughing off and the mass of fungal spores can be observe easily. Based on some investigations, pathogen is inactive during the winter months and its activity starts from spring and terminates at the end of summer season. The disease is more sever when it occurs in the orchards with poor disease management as well as water and nutrient deficiency. Some cultural practices like a well-managed irrigation and enough fertilizing with no pruning during the summer months, are good disease control measures, which in this paper are discussed.

Najafiniya  M.,  Bagheri  A., Azadvar M. & Salehi M. 2016. The situation of witches broom disease of sour lime in Iran. Plant Pathology Science 5(2):23-31.

Lime is one of the most important economic and horticultural plants in the southern part of Iran. Among the diseases of citrus in south of Iran, Witches Broom Disease of Lime (WBDL) is one of the major citrus diseases. The causal agent of WBDL is a phytoplasma with the proposed name, Candidatus Phytoplasma aurantifolia. The symptoms of disease start with appearance of witches broom at one-side of the infected tree. The disease then spread to whole parts of plant showing leaf proliferation, shortened internodes, small and pale green leaves, no formation of any spine, flower or fruit and finally death of the infected plants. To control the disease, integrated management and cultural practices has shown to be effective methods. Elimination of symptomatic trees as well of the newly emerged infected branches, chemical or mechanical weed control and a periodic spraying by systemic pesticides against the vector insect, or a combination of these methods is highly recommended. Among the control measures, chemical control of the vector has showed is very effective for reducing the disease spread and severity.