NITROGEN NUTRITION AND SUSCEPTIBILITY TO FIRE BLIGHT (E. AMYLOVORA) OF PYRACANTHA CV. MOHAVE : A PRELIMINARY STUDY USING AN HYDROPONIC SYSTEM

It is often considered that susceptibility to fire blight depends on the physiological condition of infected plants.
In this respect, mineral nutrition might play a part through its contribution to shoot growth and content.
To check this, pyracantha ‘Mohave’, an easy to propagate, fast growing, susceptible variety was chosen.
Cuttings were rooted in aerated desionized water and then young plants were grown in nutrient solutions using hydroponic culture to avoid interactions which are likely to occur with solid substrates.
In our preliminary study 3 nitrogen doses were used (NI = 25, N2 = 100, N3 = 200 mg/l). Susceptibility was estimated by measuring the length of necrosis of inoculated shoots.
Physiological condition was characterized both by shoot lengthening and nitrogen content of the different parts of cuttings.
First results show a link between nitrogen rate in solutions, length of necrosis and nitrogen content of infected shoots.
The experimental design can also be used to test any other element or nutrient combination.

IV International Workshop on Fire Blight

A. CADIC, F. LEMAIRE, J.P. PAULIN

https://doi.org/10.17660/ActaHortic.1987.217.22