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The chemical compound 2-acetyl-1-pyrroline (2-AP) is a major contributor to the fragrance of rice. This report presents the first efforts towards determining the quantities of 2-AP in rice by grating-based visible–near-infrared reflectance spectroscopy using a diverse set of rice varieties. Calibration models generated by preprocessing treatments using Design of Experiment (DoE) and 'one-variable-at-atime' (OVAT) methods were compared and optimized. A modified partial least squares model with "2, 3, 1, 1"/SNV and 174 variables yielded a coefficient of determination for calibration values of 0.978. The results showed that a DoE-based preprocessing selection could efficiently and accurately optimize 2-AP calibration models, with advantages over OVAT. The findings of this study provide high-throughput screening technology for high-precision fragrance quality breeding, monitoring and control in the rice industry. The method demonstrated here also has potential for application in many other disciplines, including identification of plant fragrances and quality control of cereal products. • Vis-NIRS was capable of accurate quantifying 2-acetyl-1-pyrroline in diverse rice samples. • DoE preprocessing methods accurately constructed Vis-NIRS calibration equations. • The long-NIR spectroscopic region was critical for successfully establishing the 2-AP model. • Using Vis-NIRS in HTS proved to be a valuable tool in rice breeding and the food industry. [ABSTRACT FROM AUTHOR]

• Diverse rice samples are suitable for an accuracy NIR assay of apparent amylose, amylose and amylopectin content simultaneously. • Calibration optimal equations of NIRs with much high values. • MPLS-DA (discriminant analysis) could classify waxy and non-waxy rice with 100% accuracy. • NIRS applicable for high-throughput screening. Rice starch properties of apparent amylose content (AAC), amylose content (AC), and amylopectin content (AP) are considered as the most important factors influencing grain quality as they are highly correlated with eating quality. This report is the first effort of predicting AC and AP values in rice flours, and recognizing waxy rice from non-waxy rice using NIRS technique. Calibration models generated by different mathematical, preprocessing treatments and combinations of wavelengths and signals were compared and optimized. The model established by modified partial least squares (MPLS) with "2, 8, 8, 2"/ Inverse MSC and ∼138 wavelengths signals yielded high RSQ of 0.977, 0.928, and 0.912 for AAC, AC and AP, respectively, as simultaneous measurement. MPLS-DA (discriminant analysis) could classify waxy and non-waxy rice with 100% accuracy. This high-throughput technology is valuable for breeding programs, and for the purposes of quality control in the food industry. [ABSTRACT FROM AUTHOR]

Abstract: A recombinant inbred line (RIL) population bred from a cross between a javanica type (cv. D50) and an indica type (cv. HB277) rice was used to map seven quantitative trait loci (QTLs) for thousand grain weight (TGW). The loci were distributed on chromosomes 2, 3, 5, 6, 8 and 10. The chromosome 3 QTL qTGW3.2 was stably expressed over two years, and contributed 9–10% of the phenotypic variance. A residual heterozygous line (RHL) was selected from the RIL population and its selfed progeny was used to fine map qTGW3.2. In this “F2” population, the QTL explained about 23% of the variance, rising to nearly 33% in the subsequent “F2:3” generation. The physical location of qTGW3.2 was confined to a ~556kb region flanked by the microsatellite loci RM16162 and RM16194. The region also contains other factors influencing certain yield-related traits, although it is also possible that qTGW3.2 affects these in a pleiotropic fashion. [Copyright &y& Elsevier]

Abstract: In the current study, we explored whether chronic salicylate exposure could induce apoptosis in outer hair cells (OHCs) and spiral ganglion neurons (SGNs) of the cochlea. Guinea pig received sodium salicylate (400mg/kg/d) or saline vehicle for 10 consecutive days. Programmed cell death (PCD) executioner was evaluated with immunohistochemistry detection of activated caspase-3. Apoptosis was examined with a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method. Repeated salicylate administration activated caspase-3 and caused apoptosis in OHCs and SGNs (p <0.01 vs. saline control for both measures and in both cell types). Cell counting showed a significant loss in OHCs (p <0.01 vs. saline control), but not in inner hair cells (IHCs). Transmission electron microscopy (TEM) revealed chromatin condensation and nucleus margination in salicylate-treated cochlea. Scanning electron microscopy (SEM) demonstrated stereociliary bundles breakdown and fusion at the apical of OHCs, villous matter was discovered to attach on the surface of SGNs. These findings suggest that long-term administration of high-dose salicylate can activate caspase-3 pathway to induce OHC and SGN apoptosis. [Copyright &y& Elsevier]