Exploring the Potential of Overexpressed OsCIPK2 Rice as a Nitrogen Utilization Efficient Crop and Analysis of Its Associated Rhizo-Compartmental Microbial Communities

Abstract

Nitrogen (N) is one of the indispensable factors in rice growth and development. China holds a premier position in the production of rice and at the same time also faces higher N fertilizer costs along with serious damage to the environment. A better solution is much needed to address these issues, without disrupting the production of rice as an important cereal, while minimizing all the deleterious effects on the environment. Two isogenic lines Kitaake (WT) and its genetically modified line CIPK2 (RC), overexpressing the gene for Calcineurin B-like interacting protein kinase 2 (OsCIPK2) with better nitrogen use efficiency (NUE), were compared for their growth and development under low versus normal levels of N. NUE is a complex trait mainly related to a plant’s efficiency in extraction, assimilation, and recycling of N from soil. The microbial population was analyzed using high-throughput Illumina Miseq 16S rRNA sequencing and found that RC with CIPK2, specifically expressed in rice root, not only performed better without nitrogen fertilizer (LN) but also increased the diversity of bacterial communities in rice rhizosphere compartments (rhizosphere, rhizoplane, and endosphere). The relative abundance of beneficial bacteria phyla increased, which are known to promote the circulation and transformation of N in rhizosphere soil. To further explore the potential of RC regarding better performance under LN, the ion fluxes in root apical were detected by non-invasive micro-test technique (NMT). We found that RC can absorb more Ca2+ and NO3− under LN as compared to WT. Finally, compared to WT, RC plants exhibited better growth of root and shoot, and increased yield and N uptake under LN, whereas there was no significant difference in the growth of two rice lines under normal nitrogen (NN) treatment. We are able to get preliminary results, dealing with the OsCIPK2 overexpressed rice line, by studying the rice molecular, physiological, and chemical parameters related to NUE. The results laid the foundation for further research on N absorption and utilization in rice from the soil and the interaction with microbial communities.

Roles of Bacterial Symbionts in Transmission of Plant Virus by Hemipteran Vectors

“…It has been documented that B. aphidicola, an aphid endosymbiont, influences herbivore behaviors by modulating plant volatile profiles, implying that CMV infections reduce the abundance of B. aphidicola in aphids, which has been associated with a preference shift in aphids from infected to healthy plants (Shi et al, 2021). It is revealed that the symbiotic bacteria affect feeding tropisms and feeding behaviors of insects and influences plant infections by viruses (Frago et al, 2012;Simon et al, 2017;Khan et al, 2019;Noman et al, 2020).…”

Transcriptome Analysis Reveals Different Responsive Patterns to Nitrogen Deficiency in Two Wheat Near-Isogenic Lines Contrasting for Nitrogen Use Efficiency

“…Previous research indicated that receptor-like protein kinases (RLKs) are involved in signal transduction pathways associated with abiotic stress stimuli in plants [ 50 ]. Besides, overexpression of the genes encoding CBL-interacting protein kinase (CIPK) enables rice to exhibit a higher NO 3 − uptake capacity under low-N stress [ 51 ]. In the present study, different groups of PK genes were identified, which mainly included MAPK, RLK, and CIPK families ( Table S4 ).…”

Genome-wide identification of the peptide transporter family in rice and analysis of the PTR expression modulation in two near-isogenic lines with different nitrogen use efficiency

“…A calciumdependent protein kinase gene, esl4, which may function upstream of N-metabolism genes [55]. The overexpression of Calcineurin B-like interacting protein kinase 2 gene, OsCIPK2, could increase N use efficiency in rice [56]. OsSAPK8 is a counterpart of AtOST1 in the activation of OsSLAC1, which is a nitrate-selective anion channel in rice [57].…”