Major non-legume crops can form beneficial associations with nitrogen-fixing bacteria like Azospirillum brasilense . Our current understanding of the molecular aspects and signaling that occur between important crops like rice and these nitrogen-fixing bacteria is limited. In this study, we used an experimental system where the bacteria could colonize the plant roots and promote plant growth in wild type rice and symbiotic mutants ( dmi3 and pollux ) in rice. Our data suggest that plant growth promotion and root penetration is not dependent on these genes. We then used this colonization model to identify regulation of gene expression at two different time points during this interaction: at 1day post inoculation (dpi), we identified 1622 differentially expressed genes (DEGs) in rice roots, and at 14dpi, we identified 1995 DEGs. We performed a comprehensive data mining to classify the DEGs into the categories of transcription factors (TFs), protein kinases (PKs), and transporters (TRs). Several of these DEGs encode proteins that are involved in the flavonoid biosynthetic pathway, defense, and hormone signaling pathways. We identified genes that are involved in nitrate and sugar transport and are also implicated to play a role in other plant-microbe interactions. Overall, findings from this study will serve as an excellent resource to characterize the host genetic pathway controlling the interactions between non-legumes and beneficial bacteria which can have long-term implications towards sustainably improving agriculture.

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We investigated dual modification of normal and waxy rice starch, focusing on digestibility. Amylosucrase (AS) was applied to maximize the slowly digestible and resistant starch fractions. AS-modified starches were adjusted to 25-40% moisture levels and heated at 100 °C for 40 min. AS-modified starches exhibited a B-type crystalline structure, and hydrothermal treatment (HTT) significantly (p < 0.05) increased the relative crystallinity with moisture level. The thermal transition properties of modified starches were also affected by the moisture level. The contents of rapidly digestible starch fraction in AS-modified normal and waxy starches (43.3 ± 3.9 and 18.1 ± 0.6%) decreased to 13.0 ± 1.0 and 0.3 ± 0.3% after HTT, accordingly increasing the low digestible fractions. Although the strengthened crystalline structures of AS-modified starches by HTT were not stable enough to maintain their rigidity under cooking, application of AS and HTT was more effective in waxy rice starch than normal rice starch when lowering digestibility.

This research compares how second language learners process two types of written feedback: reformulation and direct correction. On a two‐stage composition‐and‐comparison task, 22 adult learners of English as a second language taking an academic writing course at a large midwestern U.S. university participated in a repeated‐measures study in which they wrote two argumentative essays and received feedback in the form of reformulation on one and direct correction on the other in counterbalanced fashion. During the comparison stage for each essay, learners completed think‐alouds, which were used to gauge how they processed the two types of feedback. The findings reveal that learners processed sentential and paragraph‐level errors more deeply but overlooked surface‐level errors when they received reformulation as feedback; the reverse was the case when they received direct correction. Results therefore suggest that there may not be a one‐size‐fits‐all answer for written corrective feedback but that different errors respond to feedback differently.