Soybean Nodulation Response to Cropping Interval and Inoculation in European Cropping Systems

Abstract

To support the adaption of soybean [Glycine max (L) Merrill] cultivation across Central Europe, the availability of compatible soybean nodulating Bradyrhizobia (SNB) is essential. Little is known about the symbiotic potential of indigenous SNB in Central Europe and the interaction with an SNB inoculum from commercial products. The objective of this study was to quantify the capacity of indigenous and inoculated SNB strains on the symbiotic performance of soybean in a pot experiment, using soils with and without soybean history. Under controlled conditions in a growth chamber, the study focused on two main factors: a soybean cropping interval (time since the last soybean cultivation; SCI) and inoculation with commercial Bradyrhizobia strains. Comparing the two types of soil, without soybean history and with 1–4 years SCI, we found out that plants grown in soil with soybean history and without inoculation had significantly more root nodules and higher nitrogen content in the plant tissue. These parameters, along with the leghemoglobin content, were found to be a variable among soils with 1–4 years SCI and did not show a trend over the years. Inoculation in soil without soybean history showed a significant increase in a nodulation rate, leghemoglobin content, and soybean tissue nitrogen concentration. The study found that response to inoculation varied significantly as per locations in soil with previous soybean cultivation history. An inoculated soybean grown on loamy sandy soils from the location Müncheberg had significantly more nodules as well as higher green tissue nitrogen concentration compared with non-inoculated plants. No significant improvement in a nodulation rate and tissue nitrogen concentration was observed for an inoculated soybean grown on loamy sandy soils from the location Fehrow. These results suggest that introduced SNB strains remained viable in the soil and were still symbiotically competent for up to 4 years after soybean cultivation. However, the symbiotic performance of the SNB remaining in the soils was not sufficient in all cases and makes inoculation with commercial products necessary. The SNB strains found in the soil of Central Europe could also be promising candidates for the development of inoculants and already represent a contribution to the successful cultivation of soybeans in Central Europe.

Enhanced Soybean Productivity by Inoculation With Indigenous Bradyrhizobium Strains in Agroecological Conditions of Northeast Germany

“…The present study confirms the importance of inoculation for enhanced soybean yield in Europe ( Albareda et al, 2009 ; Zimmer et al, 2016 ; Halwani et al, 2021 ). Altogether, inoculation with our isolates significantly increased the protein content, grain yield, TGW, and pod number up to an average of 24, 32, 17, and 31%, respectively.…”

“…We observed 2–4 times more nodules in both greenhouse experiments compared with the field trial, which corresponded with over three times higher soybean shoot N uptake. Nodule numbers in both greenhouse experiments were within the range of values reported for sites with a soybean-growing history in Muncheberg and Fehrow, Northeast Germany ( Halwani et al, 2021 ) and Central Germany ( Zimmer et al, 2016 ). These values are, however, lower than those in a report that used metadata involving numerous field trials in several countries and climates ( Thilakarathna and Raizada, 2017 ), re-echoing low soybean-rhizobium symbiosis in the Northeastern agro-climatic environment of Germany.…”

Визуализация in vivo клубеньков сои в полевых условиях

“…В 2021 году культуру ризобактерий в почву не вносили, а сев сои на площади 50 м 2 при междурядье 50 см (плотность ценоза 18 растений на квадратный метр) провели необработанными семенами перспективной формы сои А2, выявленной на полях Института генетики, физиологии и защиты растений в опытах 2018-2019 гг. Сев сои в 2021 г. провели необработанными семенами с учетом стимуляции клубенькообразования предысторией выращивания сои на опытном участке [5]. Для описания этапов органогенеза сои использовали общепринятую классификацию [6].…”

“…Предыстория участка, где в 2020 году в почву вносили культуру ризобактерий, позволяла ожидать хорошего клубенькообразования на корнях даже при севе необработанными семенами [5]. Первоначальные опыты, с отмывкой корневой системы на большую глубину, на всю толщину пахотного горизонта (0-30 см), показали преимущественную локализацию клубеньков в поверхностном слое чернозема, не глубже 10 см (Фиг.…”

Interactive Effects of Biochar, Nitrogen, and Phosphorous on the Symbiotic Performance, Growth, and Nutrient Uptake of Soybean (Glycine max L.)

“…Merr.) is one of the most important legume crops in numerous countries globally and is widely produced as a source of oil and protein [40,41]. Several studies observed improved biomass, nutrient acquisition, and soybean yield after biochar amendments [42,43].…”