Resources and Environment College, Henan Agricultural University, Jinshui District, No. 63, Nongye RoadHenan Province, Zhengzhou, 450002, China.
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409, USA.
BMC Plant Biol. 2023 Apr 27;23(1):224. doi: 10.1186/s12870-023-04227-6.
Selenium (Se) deficiency causes a series of health disorders in humans, and Se concentrations in the edible parts of crops can be improved by altering exogenous Se species. However, the uptake, transport, subcellular distribution and metabolism of selenite, selenate and SeMet (selenomethionine) under the influence of phosphorus (P) has not been well characterized.
The results showed that increasing the P application rate enhanced photosynthesis and then increased the dry matter weight of shoots with selenite and SeMet treatment, and an appropriate amount of P combined with selenite treatment increased the dry matter weight of roots by enhancing root growth. With selenite treatment, increasing the P application rate significantly decreased the concentration and accumulation of Se in roots and shoots. P decreased the Se migration coefficient, which could be attributed to the inhibited distribution of Se in the root cell wall, but increased distribution of Se in the root soluble fraction, as well as the promoted proportion of SeMet and MeSeCys (Se-methyl-selenocysteine) in roots. With selenate treatment, P and P significantly increased the Se concentration and distribution in shoots and the Se migration coefficient, which could be attributed to the enhanced proportion of Se (IV) in roots but decreased proportion of SeMet in roots. With SeMet treatment, increasing the P application rate significantly decreased the Se concentration in shoots and roots but increased the proportion of SeCys (selenocystine) in roots.
Compared with selenate or SeMet treatment, treatment with an appropriate amount of P combined with selenite could promote plant growth, reduce Se uptake, alter Se subcellular distribution and speciation, and affect Se bioavailability in wheat.
硒（Se）缺乏会导致人体一系列健康问题，通过改变外源性 Se 物种可以提高作物可食用部分的 Se 浓度。然而，在磷（P）的影响下，亚硒酸盐、硒酸盐和 SeMet（硒代蛋氨酸）的吸收、运输、亚细胞分布和代谢尚未得到很好的描述。
结果表明，增加 P 施用量会增强光合作用，从而增加亚硒酸盐和 SeMet 处理下 shoot 的干物质重量，适量的 P 与亚硒酸盐处理结合会通过促进根系生长来增加根的干物质重量。用亚硒酸盐处理时，增加 P 施用量会显著降低根和 shoot 中 Se 的浓度和积累量。P 降低了 Se 迁移系数，这可能归因于 Se 在根细胞壁中的分布受到抑制，但增加了 Se 在根可溶性部分的分布，以及根中 MeSeCys（Se-甲基硒代半胱氨酸）和 SeMet 的比例增加。用硒酸盐处理时，P 和 P 显著增加了 shoot 和 Se 迁移系数中的 Se 浓度和分布，这可能归因于根中 Se（IV）的比例增加，但根中 SeMet 的比例降低。用 SeMet 处理时，增加 P 施用量会显著降低 shoot 和根中的 Se 浓度，但会增加根中的 SeCys（硒代胱氨酸）比例。
与硒酸盐或 SeMet 处理相比，适量 P 与亚硒酸盐结合处理可促进植物生长，减少 Se 吸收，改变 Se 亚细胞分布和形态，影响小麦中 Se 的生物利用度。
