Relationship Between Morphological Characteristics And Varietal Resistance Of Sweet Potato To Scab Infection Caused By Sphaceloma Batatas Saw.

Ruben  M. Gapasin,; Gracia  B. Bajit,

Relationship Between Morphological Characteristics And Varietal Resistance Of Sweet Potato To Scab Infection Caused By Sphaceloma Batatas Saw.

Abstract:

The morphological characteristics of sweet potato cultivars which are resistant and susceptible to Sphaceloma batatas Saw. were determined. Susceptible cultivars have thinner cuticle, more stomates in the leaves, and more lenticels in the petioles and stems than resistant cultivars. The scab pathogen bad longer incubation period, lower infection frequency and smaller lesions in resistant than in susceptible cultivars. Highly significant positive correlation was found between thickness of cuticle and incubation period as well u between number of stomates and lenticels, and infection frequency.

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