Early establishment performance of local and hybrid maize under two water stress regimes

Abstract

Maize (Zea mays L.) is the major grain crop in South Africa where most subsistence farmers still plant landraces. The objective of this study was to compare two landrace selections of maize with two hybrids popular among small-scale farmers in KwaZulu-Natal, for seed performance and water stress tolerance during seedling establishment. Two variations of a local landrace, white (Land A) and dark red (Land B), were compared to two hybrids, SC701 and SR52. Standard germination test and electrical conductivity were used to assess seed quality under laboratory conditions. Seedling emergence was performed in seedling trays using pine bark at 25% and 75% field capacity (FC), respectively, over a period of 21days. All seed types showed high germination capacity (>93%). There were highly significant differences (p<0.001) among seed types with respect to daily germination and germination velocity index (GVI). Landraces germinated slower than the hybrids. Landraces showed a 20% better root length and 41% lower electrolyte leakage than hybrids. There were differences (p<0.001) in seedling emergence between 25%FC and 75%FC. Hybrids showed better emergence at 75% FC. At 25% FC seedling emergence was drastically reduced (>5% in all varieties). Hybrids emerged faster than the landraces in both water regimes. Landraces performed better than hybrids under stress conditions. This study showed that landraces may have the same viability as hybrids and a better tolerance to stress during early establishment of the crop.

Keywords:

• Conductivity
• emergence
• germination
• hybrids
• landrace