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The problem of genotype by environment interaction (G 9 E) is that often complicates the interpretation of trials in multiple locations, making it difficult to select genotypes adapted to different environments. AMMI model was adopted to analyze ten sugarcane genotypes in ten Venezuelan environments evaluated through two years of cultivation. The objectives of this study were to identify stable and adaptable genotypes in different locations and determine the magnitude of G 9 E interaction. The analysis of variance showed that 72% of the total sum of squares was attributed to environmental effect, indicating that the sites were diverse. The first two principal component axes were significant, and both sums contributed to 61.09% to the total of G 9 E interaction. The V77-12 genotype exhibited high yield and wide adaptability to different environments. However, the CP74-2005, CP72-2086, PR61-632, PR980, and V78-2 genotypes showed high yield but with specific adaptations through locations. The application of AMMI model facilitated the visual comparison and identification of superior genotypes for each set of environments.

The evaluation of performance stability and high yields is essential for yield trials in different environments. This study was carried out to identifysugarcane genotypesthat have both a high mean cane yield, mesured in tons of cane per hectare (TCH), and stability across seven different environments, using 11 non-parametric statistical methods: Si(1), Si(2), Si(3), Si(6), NPI(1), NPI(2), NPI(3), NPI(4), RS, TOP and DE. The data came from acane yield of 20 genotypes, as measured at seven locations over three crop-years in the sugarcane regional trials of the Instituto Nacional de Investigaciones Agrícolas (INIA) of Venezuela. The genotypes V99-213, V99-236 and V00-50 showed promising yields and stability according to all of the non-parametric statistics. The TCH presented a positive association with the TOP, NPI(2), NPI(3) and Si(6) statistics. The analysis distinguished two groups of statistics using a principal component analysis (PCA). The first group (G1) was composed of the TOP, NPI(4), NPI(2), NPI(3), Si(3) and Si(6) statistics, which were located under the concept of dynamic or agronomic stability because they are associated with yield. The other group (G2) was composed of the NPI(1), Si(1), Si(2), DE and RS statistics, which fell within the static or biological stability concept.

Genotype by environment interactions for damage caused by AbstractDiatraea spp. (Lepidoptera: Crambidae) or sugarcane stem borers are important sugarcane pests in Venezuela. The use of resistant cultivars is part of an integrated management to control these insects in many countries. The aim of this study was to evaluate a group of sugarcane genotypes for Diatraea damage in several environments, and to assess the interaction among damage caused by Diatraea and yield components. Data were collected from five sugarcane field trials located in plots belonging to the Venezuelan Sugarcane Breeding Program. Twenty genotypes were evaluated for Diatraea damage in a completely randomized block design with three replicates. AMMI and GGE biplot analyses were executed for infestation intensity (II). Genotypes that showed best stability, good yield and low damage from Diatraea spp. across environments were V99-236, V00-50 and V99-190. Cultivar CP74-2005 was the most affected by injuries of sugarcane stem borers throughout locations. Intensity of infestation (II) and index of damage (ID) were highly associated. Furthermore, high intensity of infestation (II) and index of damage (ID) caused by Diatraea disturbed the Pol % cane of the genotypes.Keywords: Genetic phenomena; control methods; AMMI; GGE biplot; stable resistance; mega-environments. ResumenLos taladradores de la caña de azúcar Diatraea spp. (Lepidoptera: Crambidae) son importantes plagas de la caña de azúcar en Venezuela. El uso de cultivares resistentes forma parte del manejo integrado para el control de esos insectos en muchos países. Los objetivos de este trabajo fueron evaluar un grupo de genotipos de caña de azúcar a los daños de Diatraea spp. en varios ambientes y determinar la interacción entre los daños causados por el complejo de insectos del genero Diatraea y los componentes de rendimiento. Los datos fueron recolectados en cinco localidades evaluadas por el programa venezolano de mejoramiento de la caña de azúcar. Veinte genotipos fueron evaluados al daño de Diatraea spp. en cinco localidades en un diseño de bloques al azar con tres repeticiones. La tasa de intensidad de infestación (II) causada por Diatraea spp. fue analizada mediante los modelos AMMI y GGE biplot. Los genotipos más recomendados por su estabilidad, buen rendimiento y menor daño por taladradores del tallo a través de los ambientes fueron: V99-236, V00-50 y V99-190. El cultivar CP74-2005 fue el más afectado por el daño de Diatraea spp. a través de las localidades. La intensidad de la infestación (II) y el índice de daño (ID) estuvieron altamente asociados. Altas tasas de intensidad de infestación (II) e índice de daño (ID) causado por Diatraea afectaron el Pol % caña de los genotipos. Palabras clave: Fenómeno

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