In the Janzen—Connell hypothesis, host-specific natural enemies enhance species diversity and influence the structure of plant communities. This study tests the explicit assumption of host specificity for soil pathogens of the genus Pythium that cause damping-off disease of germinating seeds and seedlings. We isolated Pythium spp. from soil of a tropical forest in Panama. Then, in an inoculatio...

Stand problems consistently cause significant production and management losses in Arkansas rice fields. In 2002, many fields in Arkansas had severe stand losses. Three control practices are being examined in this project for managing stand losses due to seedling diseases: 1) seed treatment fungicides, 2) development of cold-tolerant cultivars, and 3) the use of disease-suppressive production sy...

Pythium species are the most common seedling disease pathogens isolated from rice in producers’ fields in Arkansas. These studies examined the value of Pythium resistance in breeding lines with cold tolerance in early-season planting environments. These lines show promise for reliable stand establishment in Arkansas. The breeding line RU0701124 had more plants/acre and greater relative root wei...

Composts prepared from a variety of feedstocks were tested for their ability to suppress seedling and root diseases of creeping bentgrass caused by Pythium graminicola. Among the most suppressive materials in laboratory experiments were different batches of a brewery sludge compost and a biosolids compost from Endicott, N.Y. Batches of these composts that were initially not suppressive to Pythi...

Soil-borne pathogens are posited to maintain forest diversity. However, their in situ impact and spatial variation are largely unknown. We examined spatial patterns of pathogenic activity in a deciduous forest using a common garden experiment and also in a natural experiment around replicated trees, and we quantified Pythium (a soil-borne pathogen) density around individual Prunus serotina tree...

We report the first case of pythiosis from Africa in an 8-month-old dog with a chronic and ulcerative cutaneous lesion. The etiologic agent belonged to the genus Pythium. Phylogenetic analysis placed the isolate in a sister group to the other P. insidiosum strains. However, the isolate may belong to a new Pythium species.

The oomycete Pythium oligandrum is a mycoparasite and licenced biological control agent. Here, we report the draft genome sequence of P. oligandrum strain CBS 530.74, which is 36.80 Mb. It contains 341 scaffolds and 11,647 predicted protein-coding genes. As reported for plant-pathogenic Pythium species, RXLR-type effector sequences are absent.

Two independent experiments were conducted to investigate the influence of rhizosphere bacteria on the growth of Anthoxanthum odoratum and Panicum sphaerocarpon. We tested whether host-specific populations of Bacillus mycoides affected the growth of their Anthoxanthum and Panicum hosts and whether host-specific differences in Bacillus populations modified the strong detrimental effect of the ro...

abstract the pythium spp. are known as the principle agents of seedling blight, damping-off and root rot of cucurbits. this study was performed for determination of pythium species involved in this diseases as well study their pathogenecity on different cucurbits. the numerous samples were taken at cultivation seasons 2006- 2007 from the fields of cucumber, tomato, egg plant, muskmelon, cucurbi...