SUSCEPTIBILITY OF PISTACHIO ROOTSTOCKS TO VERTICILLIUM DAHLIAE AND ARMILLARIA MELLEA-A PROGRESS REPORT

Pistachio rootstocks were evaluated for susceptibility to Verticillium dahliae and Armillaria mellea each in separate field experiments. Pistacia atlantica, P. integerrima, P. integerrima x P. atlantica, P. atlantica x P. integerrima, nursery-budded with P. vera ‘Kerman’, were planted in 1992 in a field infested with V. dahliae. The microsclerotia level in the field was increased, prior to planting the trees, by discing in V. dahliae-infected tomato plants.
In fall of 1992, there were approximately 25 microsclerotia per gram dry soil in three quarters of the trial and 13 microsclerotia in the fourth quarter.
During the first two growing seasons, two trees on P. atlantica and one each on P. integerrima and P. integerrima x P. atlantica died.
Verticillium wilt symptoms were present in 25 percent of trees on P. integerrima x P. atlantica, 3 percent of trees on P. atlantica, and 2 percent of trees on both P. integerrima and P. atlantica x P. integerrima. Susceptibility to Armillaria mellea was examined by planting P. atlantica, P. terebinthus, P. integerrima and P. integerrima x P. atlantica trees in orchard sites naturally infested with the pathogen.
At the end of three years, all P. terebinthus trees were healthy whereas 33 to 44 percent of the other three roostock trees had succumbed.

I International Symposium on Pistachio

B.L. Teviotdale, L. Epstein, L. Ferguson, W. Reil

https://doi.org/10.17660/ActaHortic.1995.419.59