A NEW SPECIES OF ERIOPHYID MITE FROM BRAZIL (Acari: Trombidiformes)

On a survey of plant mites in the State of São Paulo, Brazil, a vagrant eriophyid mite on the leaves of Luffa cylindrica was collected and proved to be new for Science. It is herein described and figured.

Agropyron mosaic virus (Agropyron mosaic virus).

AgMV has been reported in North America and Europe and is not considered a major pathogen on wheat, although it has pathogenic potential if present at high incidences (Slykhuis, 1962a). AgMV is transmitted by the widely distributed eriophyid mite Abacarus hystrix and can be mechanically transmitted by rub-inoculation with infected plant sap experimentally. No clear evidence is available of AgMV increasing in distribution.

Agropyron mosaic virus (Agropyron mosaic virus).

AgMV has been reported in North America and Europe and is not considered a major pathogen on wheat, although it has pathogenic potential if present at high incidences (Slykhuis, 1962a). AgMV is transmitted by the widely distributed eriophyid mite Abacarus hystrix and can be mechanically transmitted by rub-inoculation with infected plant sap experimentally. No clear evidence is available of AgMV increasing in distribution.

Transmission characteristics of allexiviruses by the eriophyid mite, Aceria tulipae (Keifer) (Acari: Eriophyidae) from naturally mixed infected garlic (Allium sativum L.)

The transmission characteristics of members of the genus Allexivirus to leek (Allium porrum L.) by its eriophyid mite vector, Aceria tulipae (Keifer), were studied. Prior to conducting transmission tests, colonies of nonviruliferous A. tulipae were established on healthy leek seedlings. A single A. tulipae transmitted the viruses with up to 50 % efficiency but transmission efficiency increased when > 10 mites per plant were used. Allexiviruses were acquired by A. tulipae after a minimum acquisition access period (AAP) of 30 minutes, whereas transmission tests suggest that a one hour inoculation access period (IAP) was needed for successful transmission. Allexiviruses were transmitted from garlic to leek plants by A. tulipae and mixed infections by more than one virus were observed. ShVX, GarV-A, -C, -D, and -B were detected in most inoculated plants, whereas other members of the genus (GarV-E, -X, and GarMbFV) were found only occasionally. None of the mites that originated from eggs deposited on infected plants transmitted allexiviruses, indicating that the viruses are not transmitted transovarially. No latent period was demonstrated. Taken together, these data suggest a semipersistent mode of transmission of Allexivirus members by A. tulipae. The output of this study will assist in the better management of the vector and the associated diseases.