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Nitrogen (N) deficiency is a major yield-limiting factor in rice production. The objective of this study was to identify putative QTLs for low-N stress tolerance of rice, using an advanced backcross population derived from crosses between an indica cultivar '93-11' and a japonica cultivar 'Nipponbare' and genotyped at 250 marker loci. Plant height, maximum root length, root dry weight, shoot dry weight and plant dry weight under two N conditions and their relative traits were used to evaluate low-N tolerance at the seedling stage. A total of 44 QTLs were identified on chromosomes 1, 2, 3, 4, 5, 6, 8 and 9. Eight intervals on five chromosomes were identified to harbour multiple QTLs, suggesting pleiotropism or multigenic effects according to the contributor of alleles. Some QTL clusters were found in the nearby regions of genes associated with N recycling in rice, indicating that the key N metabolism genes might have effects on the expression of QTLs. Several unique QTLs for relative traits were detected, which suggested the specific genetic basis of relative performance. [ABSTRACT FROM AUTHOR]

Presents information on a study which described the use of one-dimensional piecewise linear map in digital chaotic encryption systems. Kinds of digital encryption systems; Finite-precision effect analysis of digital chaotic systems; Simulation results; Conclusions.

Previous studies in Arabidopsis reported that the PPR protein SOAR1 plays critical roles in plant response to salt stress. In this study, we reported that expression of the Arabidopsis SOAR1 (AtSOAR1) in rice significantly enhanced salt tolerance at seedling growth stage and promoted grain productivity under salt stress without affecting plant productivity under non-stressful conditions. The transgenic rice lines expressing AtSOAR1 exhibited increased ABA sensitivity in ABA-induced inhibition of seedling growth, and showed altered transcription and splicing of numerous genes associated with salt stress, which may explain salt tolerance of the transgenic plants. Further, we overexpressed the homologous gene of SOAR1 in rice, OsSOAR1, and showed that transgenic plants overexpressing OsSOAR1 enhanced salt tolerance at seedling growth stage. Five salt- and other abiotic stress-induced SOAR1-like PPRs were also identified. These data showed that the SOAR1-like PPR proteins are positively involved in plant response to salt stress and may be used for crop improvement in rice under salinity conditions through transgenic manipulation. [ABSTRACT FROM AUTHOR]

Quantitative trait loci (QTL) for the length of the dehiscence that forms at the base of the anther [basal dehiscence length (BDL)] in rice ( Oryza sativa L.) were analyzed using chromosome segment substitution lines (CSSLs) developed from 9311 (as the recipient) and Nipponbare (as the donor). Using composite interval mapping with QTL Icimapping software, seven QTLs were detected on Chr. 2, 7, 8, 9, 10, and 11. These QTLs explained 6.49-18.15 % of the total phenotypic variation for BDLin CSSLs during 2012. qBDL8, qLDB10 and qBDL11 were derived from 9311 allele. The other four QTLs had negative effects on BDL and were derived from Nipponbare alleles. qBDL2- 2, qBDL7, qBDL8, qBDL10 and qBDL11 were consistent with some heat tolerance QTLs mapped with different indexes and populations by other researchers. Among them, qBDL2-2 and qBDL10 were found to have significant effect on heat tolerance in populations derived from Nipponbare in previous reports, which suggests that those two QTLs were stable in different environments and can be used in heat tolerance breeding. The results indicated that QTL analysis of the long basal dehisce trait might be an effective index to identify the heat tolerance of rice in an ordinary environment. [ABSTRACT FROM AUTHOR]