57. YLD-1 Yellow leaf disease appears first on older leaves. The lower surface of the midrib turns from green to bright yellow (A) or pink or reddish (B and C). The upper surface of the midrib may remain white or greenish white.

Enfermedad de la hoja amarilla aparece primero en las hojas mas viejas. La superficie baja de la nervadura central cambia de verde a amarillo brillante (A) o rosado o rojizo (B y C). La parte de la superficie superior de la nervadura central puede permanecer blanca o verdosa blanca.

(Reproduced, by permission, from J. C. Comstock, J. E. Irvine, and J. D. Miller, 1994, Yellow leaf syndrome appears on the United States mainland, Sugar J. [March], pp. 33-35)