Glomerella magna, cause of a new anthracnose of cucurbits
- PhytoPathology, 54, p.452-454, 1964 .
Glomerella magna is described as a new heterothallic species of Glomerella. The mean size of perithecia (420 x 263 [mu]), asci (100 x 15 [mu]), and ascospores differs from those of any previously described Glomerella. The larger size of asci and ascospores is the distinguishing feature of G. magna. The asexual stage is characteristic of the genus Colletotrichum. Conidia average 28 x 4.5 [mu]. G. magna is pathogenic on many species of cucurbits; the most important are watermelon, squash, pumpkin, and cantaloupe. G. magna differed in disease reaction from races 1, 2, and 3 of G. cingulata var. orbiculare on 10 cucurbit hosts inoculated with each of the 4 isolates. Cucumbers are sometimes parasitized, but are a less important host.