ABSTRACT A series of laboratory tests were conducted to investigate potential effects of fungus gnat (Bradysia impatiens) feeding damage on susceptibility of geranium seedlings (Pelargonium x hortorum) to infection by the root rot pathogen Pythium aphanidermatum. Effects were compared with those from similar tests in which the seedlings were mechanically wounded by severing the root tip with a ...

Burkholderia cepacia AMMDR1 is a biocontrol agent that protects pea and sweet corn seeds from Pythium damping-off in field experiments. The goal of this work was to understand the effect of B. cepacia AMMDR1 on Pythium aphanidermatum and Aphanomyces euteiches zoospore homing events and on infection of pea seeds or roots. In vitro, B. cepacia AMMDR1 caused zoospore lysis, prevented cyst germinat...

Diagnosis of Pythium keratitis is problematic due to the difficulty in obtaining a culture report resulting in unnecessarily prolonged usage of antimicrobial medication due to misdiagnosis. This study evaluated and compared nested PCR technique with culture and immunoperoxidase staining assays of Pythium insidiosum in paraffin-embedded corneal tissues from patients with suspected fungal keratit...

We describe the ecological niche of the human and animal pathogen Pythium insidiosum within endemic agricultural areas of Thailand. Samples were collected from irrigation water, including rice paddy fields, irrigation channels and reservoirs. Zoospores of P. insidiosum were captured from water by the use of a sterile human hair baiting technique. Pythium isolates were identified based on phenot...

The influences of Gaeumannomyces graminis var. tritici (which causes take-all of wheat), Rhizoctonia solani AG-8 (which causes rhizoctonia root rot of wheat), Pythium irregulare, P. aristosporum, and P. ultimum var. sporangiiferum (which cause pythium root rot of wheat) on the population dynamics of Pseudomonas fluorescens 2-79 and Q72a-80 (bicontrol strains active against take-all and pythium ...

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...