Abstract: Pot experiments in greenhouse and screen house were conducted to investigate the effect of environmental conditions on Mn deficiency of winter wheat (Tritum aestivum) and the endurance of three wheat varieties to Mn deficiency. It was observed that the wheat grown in greenhouse appeared serious Mn deficient sysmptom, but that transferred from screen house to greenhouse only showed slight Mn deficient symptom, due to its absorbing much Mn²⁺ originated from rainfall and waterlogging, indicating that rainfall is one of the important environmental factors affecting the Mn nutrition of wheat. The variety 3317 had a higher endurance of Mn deficiency and could absorb more Mn than the other two varieties. It is also found that Maimai weed had a strong capability of absorbing Mn, which is a major competitor with wheat to the Mn absorption in soil rhizosphere.

Key words: Mn deficiency, Environmental condition, Wheat variety, Weed