Screening of Gladiolus germplasm for agronomic performance and resistance against corm rot disease
A field experiment was conducted to evaluate the agronomic performance and resistance of Gladiolus germplasm against corm rot disease caused by Fusarium oxysporum Schlecht. f. sp. gladioli (L. Masey) W.C. Snyder & H.N. Hans. Among the 23 Gladiolus varieties tested, Glad Red exhibited the highest spike length of 55 cm followed by Advanced Red (50.2 cm) and White Prosperity (49.5 cm). Highest number of flowers (13 per spike) was recorded in Rose Supreme, Jester Ruffled Yellow, Princess Margaret Rose and Chinon. Glad Red depicted highest field life of flowers (42.5 days), followed by Friendship (42.5 days), Peter Pears (38.7 days) and Chinon (37.3 days). Different varieties showed 6.6 – 56.6% disease incidence and 0 – 33.3% mortality. Advanced Red, White Prosperity, Violetta, San Remo and Yellow Glad were found comparatively more resistant to corm rot disease with disease incidence of 0 – 10%. Indian variety Aarti was found to be the most susceptible to corm rot disease with disease incidence of 56.6%. Disease incidence was significantly and positively correlated with corm size. The present study concludes that Advanced Red and White Prosperity are the most suitable Gladiolus varieties for cultivation under agro-climatic conditions of Pakistan, having best floral characteristics and resistance against corm rot disease.
Key words: Corm rot disease, disease resistance, Fusarium oxysporum f. sp. gladioli, germplasm screening, Gladiolus.