Estimation of Heterosis of Elite Maize (Zea mays L.) Hybrids in 2014 at Bako, Ethiopia

Maize (Zea mays L.) is an important food crop in Ethiopia, but its productivity in farmers’ fields throughout the country is generally low due to use of traditional low-yielding open-pollinated maize varieties and limitation of improved maize varieties. Exploitation of maize heterosis  through the development of modern high yielding hybrids and synthetics  has  gradually replaced the  low  yielding  maize  populations at a faster rate in maize growing regions of the world. The tested 48 single cross hybrids were developed by crossing eight inbred lines as females along with six other inbredlines as males using design II mating schemes ( l x t)  in the year 2013.  The hybrids along with standard checks were evaluated at Bako national maize research center during 2014 main season using 5 x 10 alpha lattice design with two replications. The objectives were to evaluate the heterotic performance of the elite maize hybrids with respect to yield and yield related traits. Line × tester analysis was used to estimate the combining ability for yield related traits. The Statistical Analysis Systems (SAS) was used to analyze the data. Data were recorded for grain yield and yield related traits. Analysis of variance revealed significant variation at (p< 0.01) for most of traits and at (p<0.05) for days to maturity, number of kernels per row among genotypes except number of ears per plant. The hybrids also showed significant variation except ears per plant and number of kernels per rows. L6 x T2 (13.2 t ha -1 ), L4 x T2 (12.5 tha -1 ) and L3 x T3 (10.9 t ha - 1 ) performed better for grain yield and higher heterosis for most traits studied. Besides, high positive heterosis for grain yield and its components was found for greater than twenty four of the studied hybrids. It can be concluded that for the heterotic hybrids further evaluation of these breeding materials at more locations and year, is advisable to confirm the promising results observed in the present study. Key words : Grain yield, Heterosis, Maize