CE: 1915 CF: cag032202261
Spatial distribution in the leaf limb of orange rust (Puccinia kuehnii (W. Krüger) E. J. Butler) in sugarcane
Distribución espacial en el limbo foliar de la roya naranja (Puccinia kuehnii (W. Krüger) E. J. Butler) en caña de azúcar
1 Estación Territorial de Investigaciones de la Caña de Azúcar (ETICA Centro Villa Clara), Villa Clara, Cuba
2 Instituto de Investigaciones de la Caña de Azúcar, Carretera CUJAE km 1½, Boyeros, La Habana, Cuba, CP 19390
The orange rust of the sugar cane (Puccinia kuehnii (W. Krüger) E. J. Butler) is a disease of potential danger for the sugar industry in Cuba. The objective of the research was to determine the spatial distribution of orange rust in leaves infected by P. kuehnii, type of distribution of the pustules and the possible use of a quantitative variable that allows estimating the affected leaf area with a superior precision to observation of the human eye. From the cultivar C01-227 (susceptible to the disease), 25 leaves were collected and the +5 leaf was selected. The type of spatial distribution of the pustules was determined by calculating the variance / mean ratio and the Morisita index. A maximum of 6.88 pustules per cm2 was determined in leaves with 25 % of affected leaf area and an average of 2.26 in leaves with affectation from 5 to 25 %. The pustules for square centimeters was significantly higher in the middle and apical thirds; but in the third of the leaf, their value average or their maximum is not related directly with area affected in the leaf.