Abstract
Ten genotypes of a differential host series, each possessing different major (R) genes effective against races of Phytophthora infestans, were grown in a glasshouse to produce plants ranging between 3- and 10-wk-old at the time of inoculation. Detached leaflets were inoculated with a suspension of 2·5, 5, 10, 20 or 50 × 103 zoospores ml−1 applied as a single drop or a covering of fine droplets. Plants expected to show susceptibility uniformly gave spreading sporulating lesions, but resistance was variably expressed, with symptoms ranging from hypersensitive or symptomless reactions indicating immunity to spreading sporulating lesions covering all the leaf surface. Immune reactions were most prevalent on leaflets of flowering plants (8–10-wk-old). The incidence of immune reactions was greater with the drop than with the spray method of inoculation and decreased as spore concentration increased.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
