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Remarks (public):For a complete description including images see www.cababstractsplus.org/dfb 
Remarks (internal):Leaf mould (optimum temperature 22-24°C) in temperate regions is almost invariably a disease of the glasshouse crop; in the tropics it is most severe at cooler periods when air moisture is high. Leaf and sepal penetration is stomatal without appressoria. The importance of high RH for penetration, lesion growth and sporulation has long been recognised. More recently (49, 2654) it was shown that in the glasshouse disease incidence could be decreased (and yields increased) by limiting the periods of high RH. There was less leaf mould at a constant 20°C compared with 20°C (day) and 13°C (night) temperature regime. The biology of F. fulva has been extensively studied (5, 257; 9, 566; 17, 634, 778; 18, 142; 47, 1298). Control measures will depend in part on the method of cultivation, types of cv., distribution of physiologic races and probably the geographical locality. Ogilvie (1969) has discussed control in glasshouse growing. The considerable breeding work in N. America and Europe has used oligogenic resistance in L. chilense, L. hirsutum, L. peruvianum and L. pimpinellifolium. Several resistance (R) dominant genes have been identified. Each R gene controls resistance to certain races and new races arise, e.g. the gene Cf5 gave immunity from races 6, 10, 11 and 12 (14, 202; 15, 690; 25, 528; 27, 543; 42, 154; 44, 1253; 1254, 1255a; 50, 3181; 51, 1935; 53, 277; 54, 4153, 4154). Fungicide spraying is effective and may have to be employed in the tropics where resistant cvs. may be unavailable and/or agronomically unsuitable. Satisfactory results have been given by chlorothalonil, maneb, maneb+Zn, metiram and nabam+Zn sulphate; Cu also gives some control and benomyl has been successfully used in glasshouse tomatoes (33, 767; 37, 600; 41, 677; 52, 493, 2372; 53, 678).  
Description type:Non-original description 
Description:Fulvia fulva (Cooke) Cif., Atti dell'Istituto Botanico della Universita e Laboratorio Crittogamico di Pavia Serie 5 10(1): 246, 1954.
= Cladosporium fulvum Cooke, Grevillea 12: 32, 1883.
Colonies effuse or on indistinct leaf spots, velvety. Fruiting amphigenous but mostly hypophyllous, olivaceous to brown, with a paler margin; primary mycelium internal. Stroma present, pale brown, up to 30 x 10 µm, stromatal cells 2,5-5 µm diam. Conidiophores in loose fascicles arising from the stroma, divergent, unbranched or occasionally branched at the base, flexuous, narrow at the base, becoming broader at the apex, unilateral nodose swellings present which proliferate as small lateral branches, smooth, pale brown to dark at the apex, septate, 57-125 (-200) x 2,5-7 µm; conidial scars conspicuous and thickened. Conidia pale to dark brown, cylindrical or ellipsoid, smooth, straight or mildly curved, in chains which are often branched, 0-1 (-3)-septate, 16-40 x 5-7 µm (Ellis, 1971, 12-47 x 4-10 µm); hilum thickened and conspicuous, sometimes raised.
Hosts: Lycopersicon esculentum.
Disease: Leaf mould of tomato is a major disease of this crop. The first symptoms are pale chlorotic spots (margins indefinite) on the upper leaf surface. Sporulation, on the lower surface beneath the spots, is downy, light grey, becoming buff to tawny brown or olive green. Defoliation may occur. Infection of blossoms and fruits is much less important. There was an interval of c. 6 weeks between the incidence of severe leaf colonization (50% leaf area) and decreases in yield (48, 1982).
Geographical distribution: Worldwide (CMI Map 77, ed. 5, 1972).
Physiological specialization: There has been extensive work on races of F. fulva; 12 have been reported, and combinations of some of these (16, 571; 22, 81; 30, 250; 34, 111; 40, 710; 44, 1255b; 46, 2369k; 48, 2704i; 50, 3182; 51, 1934; 52, 3224).
Transmission: By air-dispersed conidia; these were considered to be viable for 9-12 months under adverse conditions (18, 142). Seed contamination may occur.
Literature: Butler & Jones, Plant Pathology, 1949; Ellis, Dematiaceous Hyphomycetes, 1971; Ogilvie, Diseases of Vegetables, 1969 (control in the glasshouse); Barksdale, Good & Danielson, Agriculture Handbook, US Department of Agriculture 203, 1972 (advisory, tomato diseases); McKeen, Publication Canada Department of Agriculture 1479, 1972 (advisory, tomato diseases); Kaars, Sijpesteijn & Van Dijkman, in Fungal Pathogenicity and the Plants Response, Ed. by Byrde & Cutting, pp. 437-445, 1973 (host-parasite interaction).

 
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