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Disease Note Fusarium Yellows of Celery in Texas. R. D. Martyn, Texas Agricultural Experiment Station, College Station 77843. L. W. Barnes, and J. Amador. Texas Agricultural Extension Service, College Station 77843, and Texas Agricultural Extension Service, Weslaco 78596. Plant Dis. 71:651. Accepted for publication 21 April 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0651E. Fusarium yellows of celery (Apium graveolens L. var. dulce De.)
caused by Fusarium oxysporum Schlect. f. sp. apii Nelson & Sherb. was
confirmed in Texas from the Lower Rio Grande Valley. Plants within a
commercial planting of the cultivar June Belle 1622 showed typical
vascular wilt symptoms, including yellowing, wilting of petioles or of
whole plants, and vascular discoloration and necrosis. Isolations
consistently yielded F. oxysporum. Monoconidial isolates (10
microconidia per milliliter) were used to inoculate 6-wk-old plants of
the cultivars Golden Detroit (yellow type) and Tall Utah 52-70 HK and
Tall Utah 52-70 R Improved (green types). Inoculum (10 ml) was
pipet ted onto the root ball of each plant, and the plants were
transplanted into pots (two plants per pot with seven replicates)
containing a pasteurized sand/peat mix. Symptoms appeared in 4 wk,
and final disease assessment was made after 7 wk. All three cultivars
were diseased (40--60% wilt and death) and showed characteristic
symptoms of Fusarium yellows. F. oxysporum was reisolated from
diseased plants. On the basis of susceptibility of both yellow and green
cultivars, the Texas isolate is designated as F. o. f. sp. apii race 2 (1).
Race 2 first appeared in California in 1978 (2) and has since been
reported in Michigan (1982) and New York (1984). Celery is a new crop
in Texas, and Fusarium yellows poses a potential threat to continued
celery production. |