NH4 toxicity in higher plants: a critical review
نویسندگان
چکیده
Ammonium (NH4) toxicity is an issue of global ecological and economic importance. In this review, we discuss the major themes of NH4 toxicity, including the occurrence of NH4 in the biosphere, response differences to NH4 nutrition among wild and domesticated species, symptoms and proposed mechanisms underlying toxicity, and means by which it can be alleviated. Where possible, nitrate (NO3) nutrition is used as point of comparison. Particular emphasis is placed on issues of cellular pH, ionic balance, relationships with carbon biochemistry, and bioenergetics of primary NH4 transport. Throughout, we attempt to identify areas that are controversial, and areas that are in need of further examination.
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