Effect of warm temperature and water shortages on early growth of Lepidium meyenii Walpers

Abstract

Increasing water deficits and warming temperatures due to climate change threaten agricultural systems in the Peruvian Andes, where environmental conditions are themselves challenging. Lepidium meyenii Walpers also known as "maca" is an endemic root crop that can tolerate adverse conditions such as low temperatures and high UV radiation, but little is known about its response to drought. This study aimed to test the effect on maca germination and early seedling growth of water restriction under two maximum temperatures: 15 °C (current scenario) and 20 °C (warming scenario). Water restriction had either a direct or a temperature-dependent effect on germination and above ground seedling growth, which was greater at 15 °C. By contrast, its effects on seedlings growing at 20 °C were completely overcome by faster germination, initial growth, and biomass acquisition. The results are consistent with those from other crops and contribute to the understanding of how climate change is affecting high-mountain agriculture.