-

Albinism is a disease in early stages of seedling formation that occurs more or less in citrus seedbeds. The complete failure of the leaves to manufacture chlorophyll eventually results seedlings to die. The investigation to find out the causal agent of this disorder has attracted the attention of researchers for many years. In the first stages of studies some
species of Aspergillus spp. were introduced as calise of albinism, but then relation of
Alternaria alternata were cleared. This fungus is a saprophyte or weak parasite that infests seeds and its metabolites inhibits chlorophyll biosynthesis. To investigate the effects of surface seed infesting fungi on seedlings, four important rootstock seeds: Sour orange, Poncirus, Troyer Citrange and Swingle Citromelo were collected and standard seed pathology methods of Blotter paper, Agar plate and Hiltner (moist sand) were carried out. Amongst the isolaled fungi, pathogenicity test of Alternaria alternata and Aspergillus spp. by seed inoculation were performed. Based on these tests, Alternaria atternata was cause of albinism on the plant and Aspergillus spp. with methods and conditions of this investigation did not produce any disease symptoms.
Key words: , ,.