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The aim of this study was to evaluate the contribution of inoculation with microorganisms, mainly rhizobia, on pea (Pisum sativum) production using a systematic literature review approach and a comparative analysis of grain yield to provide information to fill gaps in nontraditional regions of cultivation for this legume. A systematic search strategy was implemented, targeting papers published in scientific journals accessible through the Web of Science® (WoS) database spanning from January 1990 to April 2022. The search terms "Pisum sativum," "inoculation," and "strain" were used. The differences between the pea grain yields from plants inoculated with nitrogen-fixing microorganisms and those from noninoculated plants (control) were analyzed using thirteen field-scale studies. Overall, pea inoculation/coinoculation promoted a greater grain yield (3118 ±210 kg ha-1) than noninoculation (2338± 127 kg ha-1), showing the importance of biological nitrogen fixation for legume crop production. In the pursuit of reducing pea production costs, emphasis has been placed on inoculation, highlighting the importance of comprehending the symbiotic relationship between peas and Rhizobium. Furthermore, this research aimed to explore the interaction between Rhizobium and selected microorganisms known to enhance plant growth to identify optimal combinations to boost pea productivity.

Abstract Microalgae have been widely studied as raw materials for biofuels, food supplements and several high value products. The hypothesis is that the pH and N levels in the culture medium are important factors to increase microalgae biomass production and its by-products. Thus, this study aimed to evaluate response of Neochloris oleoabundans to sodium nitrate concentration and pH levels by assessing biomass production, pigments, total lipid content and lipid profile of cells. The experimental design was a complete factorial with two factors: sodium nitrate (NaNO3) using the doses of 0.25, 1.12 and 2.5 g L-1 and pH 5.0, 7.0 and 9.0, resulting in nine treatments and three replicates. Differences in the N concentration and pH of the in Bold’s basal medium increased up to 21.1% the production of dry biomass but also up to 36% of lipids and up to of 0.81% of carotenoid concentration in the N. oleoabundans cell. The nuclear magnetic resonance (NMR) analysis of bio-oil showed changes in the lipid profile. Oil extracted from N. oleoabundans cells growing in medium at pH 9 and in 2.5 g L−1 of NaNO3 showed fatty acids with molecular weights similar to crude soybean oil, while the oil from treatment 3 (2.5 NaNO3 g L−1) showed a slight increase in molecular weight. Overall, the best adjustment of the liquid medium to grow N. oleoabundans is at pH 9.0 and with addition of 2.5 g of sodium nitrate.