Field evaluation for resistance to the black rot pathogen <Emphasis Type="Italic">Xanthomonas campestris</Emphasis> pv. <Emphasis Type="Italic">campestris</Emphasis> in cabbage (<Emphasis Type="Italic">Brassica oleracea</Emphasis>) |
| |
Authors: | Email author" target="_blank">Brita?Dahl?JensenEmail author Said?M?S?Massomo Ignas?S?Swai John ?Hockenhull Sven?Bode?Andersen |
| |
Institution: | (1) Department of Plant Biology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark;(2) Department of Agricultural Sciences, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark;(3) Sokoine University of Agriculture, 3005, Morogoro, Tanzania;(4) Tengeru Horticultural Research Institute, P.O. Box 1253, Arusha, Tanzania;(5) Asian Vegetable Research and Development Center – Africa Regional Program, P.O. Box 10, Duluti, Arusha, Tanzania |
| |
Abstract: | Black rot, caused by Xanthomonas campestris pv. campestris, (Xcc), is one of the most serious diseases of crucifers world-wide. Forty-nine genotypes were evaluated for resistance under field
conditions in Tanzania after artificial inoculation with Xcc race 1. Open pollinated white cabbage cultivars were generally susceptible, while Portuguese and pointed cabbages exhibited
partial resistance. Some F1 white cabbage cultivars were highly susceptible, whereas others exhibited a high level of partial
resistance. The most promising of the hybrid cultivars were T-689 F1, Gianty F1, No. 9690 F1, N 66 F1, and SWR-02 F1. Breeding
line Badger I-16 exhibited the highest level of resistance of all genotypes. The genotypes accounted for 72.9–75.5% of the
variation of the disease severity when assessed on the leaves, and 71.4% of the variation when assessed as internal black
rot in heads at harvest. High correlations (equal to or above 0.7) were found between disease severities assessed on leaves
three times during the growing season and also with the amount of internal black rot in heads. Leaf loss also was correlated
with disease severity. The high genetic determination of the trait and the high correlations between disease assessments indicate
that selection for resistance to black rot will be efficient when field screenings are carried out. Evaluation of genotypes
for disease severity on leaves during the growing season combined with evaluations of head resistance in the most promising
genotypes may be a simple method to select resistant cultivars. |
| |
Keywords: | bacterial plant disease breeding Crucifers disease control genetic determination Tanzania |
本文献已被 SpringerLink 等数据库收录! |
|