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Remarks (public):For a complete description including images see www.cababstractsplus.org/dfb 
Remarks (internal):The species is most readily distinguished from the broad concept of conidial forms of Glomerella cingulata (Stonem.) Spauld. & Schrenk by its slow growth and dark pigmentation in culture. Temperature and humidity are important factors in expression of symptoms. Development is most rapid in damp and warm conditions but is delayed or prevented by temperatures outside the range c. 7-33°C (optimum temperature between 18ºC and 25ºC), whilst high humidity is required during all stages of conidium germination, incubation and subsequent sporulation (36: 264). Use of seed free from the pathogen is important for control; chemical treatment is not always satisfactory where seed is deeply penetrated, and seed certification schemes are in force in Sweden, Australia (New South Wales & Victoria), lsrael and Germany. Although spraying of the crop can increase yield (34: 708) time of application is limited because of problems of residues (31: 584). Breeding of resistant varieties has achieved considerable success and although new races of the pathogen emerge from time to time it is one of the most satisfactory methods of control. Similar symptoms are associated with a number of unrelated microorganisms (7: 215; 9: 256; 26: 276). Antagonism has been recorded between C. lindemuthianum and Gliocladium (3: 471), Streptomyces and Actinomyces (18: 129; 36: 10); the species is sensitive to a number of antibiotics (28: 232; 36: 261, 487). Recent investigations include studies of enzyme (46, 2988; 48, 2074) and phytoalexin (43, 2522) production, serology (48, 1397) and biochemistry of infected tissues (46, 791; 49, 2231). The organism has been used as a test fungus for fungistatic activity of pyrimidine metabolites (47, 3690) and survives storage in liquid nitrogen for at least 4 yr without morphological or pathological alteration.
 
Description type:Non-original description 
Description:Colletotrichum lindemuthianum (Sacc. & Magn.) Briosi & Cav., Funghi Parass. no. 50, 1889.
= Gloeosporium lindemuthianum Sacc. & Magn., Michelia 1: 129, 1880.
Acervuli on fruits, leaves and stems, rounded or elongated, attaining c. 300 µm diam., intra-epidermal and sub-epidermal, disrupting outer epidermal cell walls of host; occasional cells of acervulus develop as setae which are brown, septate, hardly swollen at the base and slightly tapered to the rounded paler apex, 4-9 µm wide and usually less than 100 µm long. Conidiophores non-sepate, hyaline or faintly brown, cylindrical, phialidic. Conidia hyaline, cylindrical, with both ends obtuse or with base narrow and truncate, non-septate, uninucleate, 11-20 x 2,5 µm 5,5 µm. Colonies on PDA growing slow (approx. 6 cm diam. in 10 days at 22-24ºC), at first grey, rapidly becoming dark with compact aerial mycelium; in old cultures sectors with whitish aerial mycelium sometimes occur. Acervuli with pale salmon spore masses most conspicuous in zone behind advancing edge and in centre of colony, elsewhere often more or less concealed by aerial mycelium; solitary phialides common; reverse near black. Appressoria infrequently formed from mycelium in old cultures or slide cultures, cinnamon brown, ovate to obclavate or faintly lobed, 6-18 x 4-9 µm, borne on hyaline thin-walled supporting hyphae.
Hosts: On French, runner and broad beans, Phaseolus aborigineus, P. acutifolius, P. aurecus, P. lunatus var. macrocarpus, P. mungo, P. radiatus, cowpea, Dolichos biflorus, Lablab niger and occasionally on other Leguminosae.
Disease: Leaf, stem and pod anthracnose. Lesions on stems and pods more clearly defined than those on leaves, grey or brown, slightly sunken with raised dark brown or reddish edge, frequently bearing conspicuous light salmon pink spore masses. All vegetative parts, except pulvini, are susceptible during early stages of development; invasion of the tap root of a young plant can lead to death.
Geographical distribution: Widely distributed, present in almost all areas where beans are grown (I.M.I. Map 177, ed. 3, 1966).
Physiological specialization: The species exhibits a high degree of variability and new races pathogenic to previously resistant cultivars are frequently reported. Three strains were defined by early work on differential bean varieties in USA (3: 110) and these may represent major groups of races according to later interpretation (11: 618). As many as 9 races, which showed morphological differences on PDA as well as physiological on the host, have been obtained by single-spore isolation from one experimental plot (32: 658) and 15 races have been defined on genetic criteria (50, 2043). Differences between races in vitamin requirements and in effects on phenolic metabolism have been demonstrated (29: 404; 48, 1521).
Transmission: Overwinters in seed and on buried infected crop residues. Survives for at least 2 yr on seed (32: 114) and is capable of withstanding temperatures of -15°C to -20°C for a limited period (6: 322). Dispersal within the crop by water, air currents and contact; no extensive growth in soil has been reported.
Literature: Arx, Tijschr. Plziekt. 63(4): 171-190, 1957; Schaffnit & Boning, Centralbl. fur Bact. Abt. 2 58(9-17): 176- 254; (18-22): 360-438; (23-25): 481-508, 1925; Acimovic, Zast. Bilja 15(79): 229-981, 1964.

 
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