Kernel weight and yield improvement in a quality protein sugary-2; opaque-2 BSSS maize population using a selection index
Abstract
A 2-year study to evaluate kernel weight and yield improvement over three cycles of selection was conducted in a quality protein sugary-2; opaque-2 recovery of a BSSS maize (Zea mays L.) population. A weighted selection index of kernel weight ratio and kernel weight of normal and su2o2 segregants from heterozygous S$\sb1$ ears were used as a selection criterion. The control and selected populations were evaluated per se and in testcrosses with three su2o2 single crop testers. Kernel weight selection in populations per se resulted in a highly significant (P $<$ 0.01) increase of 0.71 g (25 su2o2-kernels) $\sp{-1}$ cycle $\sp{-1}$, and highly significant (P $<$ 0.01) indirect-effect increases of 0.61 cm$\sp3$ (25 su2o2-kernels) $\sp{-1}$ cycle$\sp{-1}$ for volume, 5.29 cm cycle$\sp{-1}$ for ear height, 8.82 cm cycle $\sp{-1}$ for plant height, and 34.01 g m$\sp{-2}$ cycle$\sp{-1}$ for grain yield. Kernel weight selection in testcross progenies resulted in a highly significant (P $<$ 0.01) increase of 4.18 g (250 su2o2-kernels) $\sp{-1}$ cycle$\sp{-1}$, and highly significant (P $<$ 0.01) indirect-effect increases of 3.54 cm$\sp3$ (250 su2o2-kernels) $\sp{-1}$ cycle$\sp{-1}$ for volume, 2.13 cm cycle$\sp{-1}$ for ear height, 4.85 cm cycle$\sp{-1}$ for plant height, and 21.89 g m$\sp{-2}$ cycle$\sp{-1}$ for grain yield. The realized heritability for kernel weight was 0.53. It was concluded that selection among S$\sb0$ plants (S$\sb1$ ears) using the weighted selection index could be effective in increasing kernel weight and grain yield.
Degree
Ph.D.
Advisors
Glover, Purdue University.
Subject Area
Agronomy
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.