Differential response of commercial hybrid and open pollinated maize seeds to mechanical damage during seed processing

Abstract

Hybrids and open pollinated varieties (OPVs) are two commercial maize seed types cultivated in Nigeria. Information on their response to mechanical damage during processing is limited. This study is thus aimed at assessing the response of hybrids and OPVs of maize seeds to mechanical damage which would facilitate fabrication of processing facilities suitable for either of the maize types. Six maize varieties: three hybids (‘New Kaduna’, ‘SDM-1’, and ‘JO-195’) and three OPVs (‘Sammaz 15’, ‘Sammaz 27’ and ‘Suwan-1-stry’) were used for the study. The seed samples were subjected to standard germination, seedling vigour analysis, accelerated ageing, conductivity and fast green tests. The result showed that all the hybrid seed varieties had more damaged seeds than their OPVs counterpart. Shoot length and root length were more affected than other parts of the seedling. There were differences in the magnitude of electrolyte leakage as well as in what time each seed type (hybrid or OPVs) passed through the phases with ‘JO-195’ having the highest rate of electrolyte leakage. Hybrid seeds had lower resistance to mechanical damage and poorer storability when compared with the OPVs. In the overall, for all the traits, ‘Sammaz 15’, the best among OPVs was more promising when compared with ‘SDM-1’ which was the best among hybrid varieties. Processing machine equipment and accessories that are suitable for hybrid seeds might be inappropriate for conditioning OPVs.

Keywords

• deterioration
• harvesting
• germination
• leachate
• physiological
• triphasic