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.

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Background and objectivesWith the interest in increasing resistant starch (RS) of cooked rice, lowering its digestibility has been attempted but not established yet. Herein, we aimed to develop a simple cost‐effective method to prepare RS‐enriched cooked rice. Various combinations of rice types, cooking methods, and additives were investigated to increase the RS content.FindingsThe high‐amylose cultivar (~28% amylose), retort‐type cooking (121°C, 30 min, 15 psi), and brown rice resulted in higher RS content than that of normal rice, conventional cooking, and white rice, respectively. The effect of various food additives in soaking water on additional RS formation was marginal except for citric acid or soybean oil.ConclusionsThe method for producing RS‐enriched cooked rice was successfully established using high‐amylose brown rice via soaking in 30–40 mg/ml citric acid solution, retort‐type cooking, and drying. Its high RS content is likely due to collective effects from starch retrogradation, amylose‐lipid complex, restricted starch swelling/gelatinization by bran layer and non‐starch dietary fiber, and chemical cross‐linking.Significance and noveltyA simple cost‐effective method was developed resulting in the highest RS content reported to date for intact cooked rice (7.60%), which can be consumed as‐is or as a rice product ingredient requiring low glycemic index properties.

Structural and digestion properties of amylosucrase-modified waxy adlay starch were investigated. The unique reaction of amylosucrase caused a decrease and an increase in the proportion of short chains and long chains, respectively, via attachment of glucosyl units to the non-reducing ends of branch chains. The digestion profile of amylosucrase-modified starch revealed that elongated branch chains were the main reason for high contents of slowly digestible and resistant starches due to formation of a more perfect crystalline structure via easy association between elongated branch chains. The glucose response in mice after consumption of amylosucrase-modified starch was similar to the response for commercial resistant starch with a gradual increase followed by a gradual decrease in blood glucose concentrations over a prolonged time. Both and tests were used to verify increased resistance to digestive enzymes caused by amylosucrase modification.