Genetic components for fodder yield and agronomic characters in maize lines

In maize hybrid development, it is essential to know the parent’s performance per se in different environments as well as the genetic base in populations in order to facilitate selection of superior lines. The objective of this work was to estimate the genetic variance and heritability while assessing agronomic behavior in 237 maize fodder lines featuring different inbred levels and origin in two different locations. Traits such as plant height, cob height, stem diameter, and fodder yield were taken. A combined variance analysis was carried out using this information. The variable mean squares showing significant differences were used to estimate the genetic variance components. Significant differences were observed (p ≤ 0.01) for the line variation source and location × line interaction in all assessed characteristics. The genetic parameter estimation provided information on the existing genetic variance and heritability among the population which is important for the progress of the selection process. Lines CLWN701, CLWN345, CML476, CML216, CLWQ232, and CML 528 measured 74.8, 72.2, 67.7, 65.8, 63.8 and 62.5 t ha-1 , respectively showed the highest yield potential for green fodder

Resistencia a ruptura y calidad fisiológica en semillas de maíz bajo compresión axial

The physical, physiological and sanitary qualities of corn seeds are reduced due to the mechanical damage caused by the mechanization of the production process. Knowing the strength and displacement critical values according to the type of endosperm will help decrease the damage during the cleaning, drying, storing and handling processes. This study assessed the strength and displacement from compression, the visible damage and the physiological quality of corn seeds from the following varieties: Cacahuacintle (floury), HS-2 (semi-floury) and Popcorn (hard) considering a humidity of 12 and 20%. The percentage of soft endosperm in Cacahuacintle, HS-2 and Popcorn was 76.20, 33.43 and 15.27%, respectively, while the percentage of hard endosperm was 5.25, 48.93 and 65.21%, respectively. The displacement and the strength for the Cacahuacintle variety was 0.8264 mm and 274.71 N, for the HS-2 variety was 0.5499 mm and 309.07 N and for the Popcorn variety was 0.5066 mm and 356.29 N, while for 12 and 20% humidity it was 0.3279 mm and 312.52 N and 0.9520 mm and 313.81 N, respectively. The damage indexes in compressed seeds were 276.67, 327.78 and 220.01 for Cacahuacintle, HS-2 and Popcorn, respectively, while for uncompressed seeds (control group) the damage indexes were 0.00. Germination was 85.20% for uncompressed seeds and 55% for those seeds subjected to fracture. The damage index was affected by the variety and the compression, but not by the humidity. Germination was not affected by the damage index, but it was affected by humidity and compression.La calidad física, fisiológica y sanitaria de la semilla se reduce debido al daño mecánico ocasionado por la mecanización del proceso de beneficio. Conocer los valores críticos de la fuerza y el desplazamiento a la compresión en función del tipo de endospermo, permitirá ayudar a disminuir el daño durante dicho proceso de limpieza, secado, almacenaje y manejo. En el presente estudio se evaluaron: la fuerza y el desplazamiento a compresión de ruptura, el daño visible y la calidad fisiológica de semillas de maíz de las variedades: Cacahuacintle (harinoso), HS-2 (semi-harinoso) y Palomero (duro) con humedad de 12 y 20%. El porcentaje de endospermo suave en Cacahuacintle, HS-2 y Palomero fue de 76.20, 33.43 y 15.27%, mientras que el de endospermo duro fue 5.25, 48.93 y 65.21%. El desplazamiento y la fuerza para Cacahuacintle, HS-2 y Palomero fue de 0.8264 mm y 274.71 N, 0.5499 mm y 309.07 N, y 0.5066 mm y 356.29 N; mientras que para 12 y 20% de humedad fue de 0.3279 mm y 312.52 N y 0.9520 mm y 313.81 N. Los índices de daño en semillas comprimidas fueron 276.67, 327.78 y 220.01 para Cacahuacintle, HS-2 y Palomero; mientras que para semillas sin comprimir (testigos) fue de 0.00. La germinación fue de 85.20 y 55% para semillas sin comprimir y para las sometidas a ruptura. El índice de daño estuvo afectado por la variedad y la compresión, pero no por la humedad. La germinación no estuvo afectada por el índice de daño, peri sí por la variedad, la humedad y la compresión