Nematode survey in deciduous fruit tree nurseries

The nematode status of nursery material is unknown. The pilot survey was conducted to determine the current status quo of the plant material. The results will show whether the implementation of the practical guidelines was successful or not.

The results in the pear nurseries were acceptable. Paratrichodorus levels need addressing but on a voluntary basis.

The results in the apple rooted layer blocks were unacceptable. The Pratylenchus was present virtually throughout with cases where treatments are required. The root-lesion nematode in the roots results in the direct transfer of this nematode into the nurseries. This was reflected in the results of the apple nurseries. The root-lesion nematode was found in 75% of the apple nursery plots and the levels in one-third of the samples were at unacceptable levels. These roots are leaving the nurseries with this infection.

The peach and apricot rootstocks can be considered clean but the stubby root nematode numbers must be monitored and controlled. Current levels of control must be maintained. The ring nematode in the plums nurseries must be addressed.

The stone fruit nurseries are relatively clean provided current control measures are maintained. There is room for improvement in the plum nurseries. The material leaving the nurseries is clean enough and the scheme is sufficient.

The root-lesion nematode situation in the pome fruit and particularly the apple material is of concern. This situation will have to be addressed from the point of view of the nurseries with regard to the rooted apple layer blocks. The presence and levels of particularly the root-lesion nematode in the apple nurseries must be addressed. This is of importance to both the nurseries and the industry.

The situation is either one of not implementing the guidelines or the guidelines are not sufficient. This issue must be discussed by the various stakeholders and the way forward will have to be advised by both the nurseries and industry.