Aboveground dry biomass partitioning and nitrogen accumulation in early maturing soybean ‘Merlin’

Abstract

The aim of the study was to determine the biomass and nitrogen accumulation in early maturing soybean plants experiencing contrasting weather conditions. Soybean (Glycine max) is a species of agricultural crop plant that is widely described in scientific publications. During 2014-2016, a field experiment with early maturing soybean 'Merlin' was carried out at Grodziec Śląski, Poland (49°48'01" N, 18°52'04" E). Results showed that the morphological traits of the plants, the yield of individual plants, and the soybean crop were all closely related to the climatic conditions. A high amount of precipitation stimulated seed development, resulting in a high production potential. The harvest index calculated for soybean 'Merlin' was high and exceeded 0.5 g g −1. The nitrogen content of the aboveground biomass increased during ontogenesis. The maximum yield of dry matter was noted at the green maturity phase, which subsequently decreased at the full maturity phase because of the loss of the leaf fraction. The variation in the effectiveness of nitrogen accumulation in seeds between 2015 and 2016 was 30%. The nitrogen harvest index values were high in each year of the experiment and exceeded 0.92 g −1. For the production of 1 ton of seeds with an adequate amount of soybean straw, plants needed, on average, 68 kg of nitrogen.

Nitrogen balance and gap of a high yield tropical soybean crop under irrigation

“…The higher relative proportion of leaves observed up to the R 2 stage may be a strategy of the plant in supplying the photoassimilate products to roots ( Portes and Araújo, 2012 ). At R 6 the senescence and mass increase of the pods decrease leaf partition to 15% or lower, as evidenced in our results and corroborated by Zajac et al. (2017) and Gaspar et al.…”

“…Concentrations of N in the roots of 4.9, 7.6 and 4.5 g kg -1 were determined for the phenological stages V 2 , R 1 and R 8 , respectively, by Pal and Saxena (1976) . In stems, levels of 15.1, 9.9 and 4.5 g kg -1 were found at stages R 3 , R 6 and R 8 , respectively, by Zajac et al. (2017) .…”

“…Concentrations of N in the roots of 4.9, 7.6 and 4.5 g kg -1 were determined for the phenological stages V 2 , R 1 and R 8 , respectively, by Pal and Saxena (1976). In stems, levels of 15.1, 9.9 and 4.5 g kg -1 were found at stages R 3 , R 6 and R 8 , respectively, by Zajac et al (2017). To sustain the high demand for N for seeds, soybeans accumulate this element in the vegetative parts and remobilize it to grains during the grain filling phase (Gaspar et al, 2017).…”

Caracterização do crescimento e acúmulo de nitrogênio em uma cultura de soja de elevada produtividade

“…Similarmente aos resultados encontrados por Zajac et al (2017), normalmente a fração mais estável em relação às outras partes da planta foram as hastes. Ainda, a proporção relativa das folhas foi alta em R2 (64.7%) e decresceu gradualmente nos estádios seguintes atingindo 27.5% em R6.…”

An innovative approach for the assessment of Bulgarian soybean cultivars

“…Worldwide research investigations are aimed at increasing the yield and quality of soybean vegetable protein. The published studies concern soybean varieties developed in other countries according to the specific climatic requirements and needs of agriculture [5,11].…”