During the growing seasons of 2009 and 2010, same tomato fields throughout Marvdasht were visited and 96 isolates of Fusarium spp. were collected from root, crown and stem of diseased tomato plants. Isolates were identified as based on morphological characteristics. They were divided into four species namely: Fusarium solani, F. pseudoanthophilum, F. oxysporum and F. equiseti. These species, being highly pathogenic to tomato, accounted for 47.9%, 18.7%, 22.9% and 10.4% of the isolates, respectively. Of these species, F. solani and F. pseudoanthophilum are the first time reports of on the disase tomato from Iran. The most frequently encountered species were F. solani and F. oxysporum with 46 and 22 isolates, respectively. Pathogenicity test was conducted for all the species of Fusarium on tomato seedlings by the methods of root dip and soil inoculation and as based upon completely randomized design. Data were analyzed through SAS and mean comparison done through LSD test. Results indicated that all the species of Fusarium except F. pseudoanthophilum caused wilt, chlorosis and root rot in tomato host plants. The results indicated isolates of Fusarium spp. To be significantly different in the disease severity at 1% probability. Host range study with F. oxysporum revealed that the pathogen caused wilt and chlorosis only on tomato and was identified as F. oxysporum f. sp. lycopersici. Thid was while, F. solani caused root rot in tomato, chickpea, Arachis hypogea and Amaranthus retroflexus.
عنوان مقاله [English]
Species Diversity of the Genus Larinus (Col.: Curculionidae) on the Host Plants Asteraceae in Kerman Region
Weevils of the genus Larinus feed on the capitula of the host plants from the family of Asteraceae, and are useful in prevention of reproduction of these weeds. Throughout the present study, the species of the genus Larinus were collected from six host plants of the family Asteraceae through timely samplings in 2010 and 2011. The seven species of the genus Larinus namely L. affinis, L. nidificans, L. onopordi, L. syriacus, L. grisescens, L. liliputanus, and Larinus sp. were collected from the tested host plants. TheShannon diversity index for Larinus species on three host plants Echinops aucheri, E. longipenicillatus and Cousinis stocksii was lower as compared with the other studied host plants. Morisita-Horn similarity index for Larinus combinations on E. aucheri, E. longipenicillatus, C. stocksii and as well on other tested host plants varied from 0.02 to 0.31. These results indicated that Larinus species combinations are not identical among the six tested host plants, since the highest abundance of the weevils L. affinis, L. nidificans and Larinus sp. were observed on the host plants E. aucheri, E. longipenicillatus and C. stocksii, respectively. Therefore, it can be concluded that the weevils L. affinis, L. nidificans and Larinus sp. are of the potential to be respectively utilized in control of the host plants E. aucheri, E. longipenicillatus and C. stocksii, in Kerman region.