Inoculant, nitrogen and phosphorus improves photosynthesis and water-use efficiency in soybean production

Abstract

Soybean yield within the Southern Africa falls below its potential despite similar climatic conditions across some agroecologies, replicable agronomic management practices and introduced improved varieties. Understanding physiological processes and water-use efficiency (WUE) of soybean offer information on bridging this yield gap. A field study was conducted in 2017 and 2018 seasons in two agroecologies (Angonia and Ruace) in Mozambique to evaluate the effects of Bradyrhizobium diazoefficiens strain USDA110 formerly known as Bradyrhizobium japonicum inoculant, nitrogen and phosphorus on nodulation, physiology and yield of non-promiscuous (Safari) and promiscuous (TGx 1740-2F) soybean varieties. Data on transpiration, photosynthesis, leaf area index, radiation interception and WUE from the beginning of flowering to maturity were collected. Transpiration rate varied considerably with interaction between locations, growth stages, varieties and treatments. At podding, phosphorus-treated soybean at Angonia transpired less (6.3 mmol/m2/s) than check plants (6.6 mmol/m2/s). Photosynthesis rate and WUE were distinct with variety, growth stages and inputs within agroecologies. For instance, in Angonia 2018 season, phosphorus fertilized TGx 1740-2F photosynthesized more at flowering (25.3 μmol/m2/s) while the lowest was phosphorus-treated Safari at podding with 17.2 μmol/m2/s. At the same site in 2017, inoculated soybean photosynthesized more at 22.8 μmol/m2/s leading to better WUE of 3.6 that corresponded to 2894 kg/ha yield. Overall, soybean WUE was higher when inoculated than N-treated, while P application yielded better. Results from this study will complement breeders’ effort in developing phosphorus efficient varieties suited for a wide range of changing climatical conditions.

Inoculant Formulation and Application Determine Nitrogen Availability and Water Use Efficiency in Soybean Production

“…Our results agree with a study conducted in 2013 and 2014 in the same locations using storm a non-promiscuous variety that recorded an increase of 523À989 kg ha À1 [6]. These results of yield increase due to inoculation also confirms previous report [5,8] where inoculation alone led to higher soybean yield that uninoculated. Although numerical average increase in yield due to inoculation was higher in Angonia and Ruace than Nampula across the seasons, percent rise in production was higher at Nampula 620À766 kg ha À1 (65%) than Angonia 918À1124 (60%) and Ruace 602À974 (52%).…”

“…Earlier studies have reported that inoculation improves yield as it leads to more available N from the BNF process. However, the yield increase varies with soybean varieties and type of inoculant especially nitrogen availability even if similar strains are used [8]. The objective of this study was to evaluate soybean WUE and yield response to liquid or solid inoculants applied to soil and on seed before planting.…”

“…Likewise, soybean producers have the quest to improve yield which necessitates inoculation with effective rhizobial strains [5][6][7]. Inoculation improves soybean yield and increases crop resilience to climatic changes effects across Africa such as drought incidences experienced in Mozambique through better water use efficiency (WUE) [8]. Although many African countries currently produce inoculant that is effective for both promiscuous and non-promiscuous soybean varieties and other legumes like beans, cowpea, and groundnuts [9], Mozambique as a country lacks the capacity and facilities for local production.…”

Prospects and Potential of Bradyrhizobium diazoefficiens Based Bio-Inoculants on Soybean Production in Different Agro-Ecologies of Mozambique

“…However, the cost of using fertilizer in particular nitrogen could be averted through the use of bio-inoculants. Bio-inoculants have been shown to increase the yield of soybean (Chibeba et al, 2020;Savala et al, 2021) and other legumes, such as cowpea (Kyei-Boahen et al, 2017), in Mozambique. The use of bio-inoculants is also limited by the lack and inaccessibility of the input at the time of planting.…”

Формування Продуктивності Сої Залежно Від Строків Сівби Та Регуляторів Росту Рослин

“…Сорти української селекції мають безліч переваг, вони високопродуктивні, посухостійкі, адаптовані до наших місцевих умов, генетично не модифіковані, за урожайністю і вмістом білка не поступаються іноземним, а інколи мають певні переваги [2,4,5]. Кожен сорт потребує вивчення оптимальних параметрів агротехнічних прийомів, серед яких важливе значення належить строкам сівби та стимуляторам росту, що особливо важливо в умовах зміни клімату [6][7][8].…”