Emergence and Seedling Characteristics of Maize Native to the Southwestern US

Abstract

Locally adapted maize landraces, which are associated with Native American groups, were traditionally planted deeply, reportedly up to 45 cm deep. Crop resources such as these should be evaluated for possible use in future sustainable farming practices. Cold temperatures often delay maize ( <i> Zea mays </i> L.) planting in the Corn Belt, possibly reducing yield potential, and spring frost and hail can damage early plantings. If producers could plant deeper and earlier in the spring, the planting season period could be extended and the potential for frost damage reduced because the growing point would be insulated below the soil surface for a longer period of time. The emergence capabilities of eleven Native American landraces were evaluated at various planting depths and compared to one Corn Belt line, BSSS-53. Emergence from depths between 5 and 45 cm was evaluated in a growth chamber study. Seedling dry matter partitioning and morphological characteristics were also examined. A field study was then performed to further test those landraces that successfully emerged (≥ 75%) from the 25 cm depth in the growth chamber. Results indicate that some of the evaluated Native American landraces have a greater capacity to emerge from depth than BSSS-53. Emergence capacity was not related to initial seed weight. Mesocotyl elongation largely accounted for successful emergence from greater planting depths. The landraces partitioned relatively more dry matter to roots than shoots compared to BSSS-53. These results suggest that several of these Native American landraces may be useful for the development of maize varieties more tolerant to deep planting.