Cyanobacterial Inoculation Enhances Nutrient Use Efficiency and Grain Quality of Basmati Rice in the System of Rice Intensification

Abstract

Field experiments were carried out to evaluate the influence of the system of rice intensification (SRI) and microbial inoculation, which revealed significant enhancement in the uptake of nitrogen and zinc in brown rice grain, husk, and straw. Increases of 30−60% in the soil dehydrogenase activity and the total polysaccharide content were recorded with an Anabaena-Mesorhizobium biofilm, while the N recovery efficiency was the highest (86%) with BF1−4 (cyanobacterial consortium) inoculant. Available N and zinc in soil were highly correlated with soil organic carbon and dehydrogenase activity, indicative of the significance of soil microbiological processes in nutrient availability. Based on the pooled data of two years, BF1 Anabaena torulosa recorded a significantly higher grain yield (4.86 Mg ha −1 ). Nitrogen fixation showed several-fold higher values in BF1−4/BF1-inoculated treatments. Inoculation with BF1−4 and biofilms (Anabaena-Trichoderma viride and Anabaena-Mesorhizobium sp.) along with only 50% N + full dose of P and K fertilizers not only led to savings of 50−60 kg of N ha −1 but also greater nitrogen and zinc uptake and localization in basmati rice grains grown under the SRI. Our investigation illustrates that microbial options can significantly contribute toward greater uptake of N and Zn, with superior efficiency-related and agronomic productivity indices.

Coinoculation with Growth-Promoting Bacteria Increases the Efficiency of Nitrogen Use by Irrigated Rice

“…In the rice intensification system (SRI) with microbial inoculation ( Anabaena –Trichoderma viride and Anabaema – Mesorhizobium sp.) contributes significantly to the increase in nitrogen and zinc absorption in Basmati rice grains and higher productivity indexes, also illustrating the benefits of a cyanobacterial consortium . In another study with grain culture and coinoculation, it was reported that the use of a microbial inoculant composed of photosynthetic cyanobacteria (Anabaema cylindrica and Nostoc muscorum) and A.…”

“…contributes significantly to the increase in nitrogen and zinc absorption in Basmati rice grains and higher productivity indexes, also illustrating the benefits of a cyanobacterial consortium. 40 In another study with grain culture and coinoculation, it was reported that the use of a microbial inoculant composed of photosynthetic cyanobacteria (Anabaema cylindrica and Nostoc muscorum) and A. brasilense, combined with nitrogen fertilization, favored maize production components. 41 In summary, we demonstrated that A. brasilense (strain Ab-V6) + P. fluorescens (strain CCTB03) combined with 70 and 90 kg of N ha −1 in coverage promoted average increases of 30 and 38.5%, respectively, in rice production using ST technology.…”

“…contributes significantly to the increase in nitrogen and zinc absorption in Basmati rice grains and higher productivity indexes, also illustrating the benefits of a cyanobacterial consortium. 40 In another study with grain culture and coinoculation, it was reported that the use of a microbial inoculant composed of photosynthetic cyanobacteria ( Anabaema cylindrica and Nostoc muscorum ) and A. brasilense , combined with nitrogen fertilization, favored maize production components. 41 …”

Evaluating the underlying physiological and molecular mechanisms in the system of rice intensification performance with Trichoderma-rice plant symbiosis as a model system

“…For example, cyanobacteria-based biofilm inoculants were found to be more effective under SRI crop management than under conventional rice management for increasing the concentrations of zinc, copper, iron, and manganese measurable in the rice grain. Also, there was a significant increase in the activity of defense-related and pathogenesis-related enzymes, as well as in the yield parameters of rice plants (Adak et al, 2016;Shivay et al, 2022). Aerobic and organic soil conditions under SRI also favor greater root growth and increased nutrient acquisition by organicallyfertilized rice plants, with reduced accumulation of toxic elements in the soil such as Fe 2+ and Mn 2+ (Turmel et al, 2011).…”

Untargeted GC–MS reveals differential regulation of metabolic pathways in cyanobacterium Anabaena and its biofilms with Trichoderma viride and Providencia sp.

“…Cyanobacteria are known to produce sugars, amino acids, auxins, vitamins, and phytohormones, which helps in stimulating plant growth ( Karthikeyan et al., 2007 , Misra and Kaushik, 1989 , Obana et al., 2007 , Rastogi and Sinha, 2009 ). In agriculture, cyanobacteria and cyanobacteria- based formulations are known to have several benefits as they improve soil stability ( Peng and Bruns, 2019 ; Prasanna et al., 2021a ), fix atmospheric nitrogen ( Pereira et al., 2009 , Singh, 1961 , Venkataraman, 1972 ), provide protection against pests and diseases ( Bao et al., 2021 , Mahawar et al., 2020 , Wiegand and Pflugmacher, 2005 ) , play an important role in the alleviation of salinity and drought ( Sneha et al., 2021 ) and biofortification of plant parts, including produce ( Nishanth et al., 2021a ; Rana et al., 2012 ; Shivay et al., 2022 ). As biofertilizers, they play a critical role in improving the availability of macro- and micronutrients, besides enriching soil carbon through photosynthesis.…”