Evidence for magnesium–phosphorus synergism and co-limitation of grain yield in wheat agriculture

Abstract

Modern crop production is characterized by high nitrogen (N) application rates, which can influence the co-limitation of harvested yield by other nutrients. Using a multidimensional niche volume concept and scaling exponents frequently applied in plant ecological research, we report that increased N and phosphorus (P) uptake in a growing wheat crop along with enhanced grain biomass is associated with more than proportional increase of other nutrients. Furthermore, N conversion efficiency and grain yield are strongly affected by the magnesium (Mg) to P ratio in the growing crop. We analyzed a field trial in Central Sweden including nine wheat varieties grown during two years with contrasting weather, and found evidence for Mg co-limitation at lower grain yields and P co-limitation at higher yields. We argue that critical concentrations of single nutrients, which are often applied in agronomy, should be replaced by nutrient ratios. In addition, links between plant P and Mg contents and root traits were found; high root number enhanced the P:N ratio, whilst steep root angle, indicating deep roots, increased the Mg:N ratio. The results have significant implications on the management and breeding targets of agriculturally grown wheat, which is one of the most important food crops worldwide.

Temporal complementarity between roots and mycorrhizal fungi drives wheat nitrogen use efficiency

“…Considering that > 80% of carbohydrates for starch synthesis in grains is from the current photosynthetic C assimilation in flag leaves and ears during grain filling (Blum, 1998; Sanchez‐Bragado et al ., 2014), we propose that AMF could positively affect photosynthetic C assimilation through P supply. Therefore, our results illustrate that the N taken up pre‐anthesis is used to support photosynthetic C assimilation during grain filling, but requires adequate amounts of other nutrients such as P, which can limit photosynthetic C assimilation especially in later crop growth stages, as wheat has been shown to accumulate P at a slower rate than N (Weih et al ., 2021). Our findings suggest that enhanced P supply by AMF can reduce the colimitation by P for photosynthesis in flag leaves and ears and thereby stimulate the production of more carbohydrates during grain filling.…”

“…The AMF may affect N utilisation efficiency through acting on C and N assimilation during grain development. As the key process in determining the utilisation of N acquired pre‐anthesis for grain formation, photosynthetic C assimilation during grain filling may also be colimited by other nutrients such as P, which accumulates more slowly than N (Weih et al ., 2021). The mycorrhizal P supply after flowering may not only increase the photosynthetic rate in flag leaves and ears, but also stimulate the antioxidant system, delay premature senescence and prolong grain filling duration (Lv et al ., 2017).…”

Tandem application of endophytic fungus Serendipita indica and phosphorus synergistically recuperate arsenic induced stress in rice

“… Nam et al (2021) provided evidence regarding Fe deficiency induced ROS generation as well as chlorosis that becomes more pronounced in the presence of phosphorus rather than its absence, which explains the improved photosynthetic capability and overall growth of plants in this study under S.i + As + P treatment as As hinders the uptake of Fe ( Mousavi et al, 2020 ); neither the availability of P alone compensate for Fe deficit, nor does it represent a guarantee of counterbalancing As toxicity ( Begum et al, 2008 ; Abbasi et al, 2021 ). Availability of P is, tacitly assumed to be, crucial for the concentrations of elements that are imperative for metabolic processes associated with photosynthesis, biomass growth and yield formation, such as Mg ( Weih et al, 2021 ); plants colonized by S. indica combined with As and P benefitted much more than the ones without its symbiosis (i.e., As + P), not only in terms of nutrient uptake but also in the element concentration of Mg, which is indispensable for the formation of chlorophyll molecule ( Weih et al, 2021 ). From this perspective, the augmented P proved rather inefficacious, when accompanied by As, for the studied genotypes.…”

Sensibilidade das análises foliar e de solo ao acúmulo de nutrientes em plantas de soja com distintas produtividades de grãos

“…Assim, para a manutenção dessa relação, o menor teor foliar de N deve vir acompanhado por menor teor de P. Ainda, é importante considerar as interações sinérgicas existente entre o N e P (AULAKH; MALHI, 2005;FAGERIA;OLIVEIRA, 2014;FAGERIA, 2001;RIETRA et al, 2017;SCHLEUSS et al, 2020). Além disso, as interações existentes entre P e Mg, principalmente pela ativação das enzimas de transferência de fosfato e síntese de açucares pelo Mg, podem explicar o menor acúmulo de um desses nutrientes ser acompanhado de uma menor concentração do outro (BERGMANN, 1992;FAGERIA, 2001;WEIH et al, 2021). No caso das plantas com menor acúmulo o de K, nota-se menores concentrações de P, Mg e S, e maiores de Ca.…”

“…Tal efeito pode estar ligado à menor disponibilidade de sítios com carga negativa para adsorção de K devido ao menor teor de MOS, quando comparada com os solos do grupo de maior acúmulo de K que apresentavam maior teor de MOS. Além disso, a competição por sítios de adsorção existente entre os cátions K+ e Mg2+, pode ter afetado a disponibilidade e a absorção de K+ (DIBB; THOMPSON JR, 1973;RANADE-MALVI, 2011;XIE et al, 2021), indicando que no caso do K, as diferenças no acúmulo, podem sim estar ligadas à disponibilidade de nutrientes. As três cultivares apresentaram resultados parcialmente concordantes com os observados na população geral ao se avaliar os teores de K no solo das populações com menor acúmulo de N, P, Ca e Mg, sendo que as cultivares Uirapuru e Tucano apresentaram os mesmos resultados na população geral com menor acúmulo de P. O padrão observado na população geral para os teores de K no solo, em que plantas com menor acúmulo estavam estabelecidas em solo com menor teor de K, se repetiu para as três cultivares, o que pode ter influenciado as variações nos teores de nutrientes na planta.…”