Influence of Pratylenchus vulnus and Meloidogyne hapla on the growth of rootstocks of rose.

Pratylenchus vulnus is involved in a desease of Rosa noisettiana 'Manetti' rose rootstock characterized by darkening of roots, death of feeder roots, and stunting of entire plants. The disease is more severe when plants are grown in silt loam soil than when they are grown in sandy loam soil. The nematodes reproduce best in silt loam soil at 20 C. Meloidogyne hapla did not affect the growh of Manetti. Rosa sp. 'Dr. Huey', Manetti, and R. odorata rose rootstocks were found to be goos hosts for P. vulnus whereas R. multiflora was less suitable. M. hapla reproduced well on R. odorata, Dr. Huey, and R. multiflora, but not on Manetti.