Year: 1991
Type: article
Abstract: Effects of different NH4+/NO3-ratios in the nutrient solutions on the plant growth and the concentrations of free NH4+ in the leaves were compared between rabbiteye and highbush blueberries.One-year-old rooted cuttings of both blueberry species were grown in sand culture and supplied with 56mg.liter-1 of N at NH4+/NO3-ratios of 0/56, 42/14, 28/28, 14/42 and 0/56.The pH of the nutrient solutions was maintained at 5.5 in each treatment.Dry weight of plant tops was greatest at 28/28 of NH4+/NO3-ratio for both species.At 42/14 or the 0/56, plants of both blueberry species showed leaf scorch.The reduction in growth caused by excessive NH4+ supply at concentrations higher than 42mg.liter-1 was more noticeable in highbush blueberries than it was in rabbiteye blueberries.Highbush blueberries grew equally well at 28/28 and 14/42 of NH4+/NO3-ratio, whereas rabbiteye blueberries grew poorly at 14/42.For both blueberry species, the concentration of free NH4+ in the leaves increased as NH4+/NO3-ratio of nutrient solution increased.When NH4+/NO3-ratio was 56/0, highbush blueberries had lower concentrations of free NH4+ in leaves than rabbiteye blueberries did.Hence, highbush blueberries are seemingly less tolerant to the excessive supply of NH4+ than do rabbiteye blueberries, although NH4+ was assimilated more efficiently in highbush blueberries.
DOI: 10.2503/jjshs.60.41
Authors: Tadashi Takamizo, Nobuo Sugiyama
Institution: The University of Tokyo
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W2016333393