Mapping of dynamic quantitative trait loci for plant height in a RIL population of foxtail millet (Setaria italica L.).

Plant height (PH) is a crucial trait for strengthening lodging resistance and boosting yield in foxtail millet. To identify quantitative trait loci (QTL) and candidate genes associated with PH, we first developed a genetic map using a recombinant inbred line (RIL) population derived from a cross between Aininghuang and Jingu 21. Then, PH phenotyping data and four variations of best linear unbiased prediction (BLUP) were collected from nine environments and three development stages. Next, QTL mapping was conducted using both unconditional and conditional QTL methods. Subsequently, candidate genes were predicted via transcriptome analysis of parental samples at three developmental stages. The results revealed that the genetic map, based on re-sequencing, consisted of 4,360 bin markers spanning 1,016.06 cM with an average genetic distance of 0.23 cM. A total of 19 unconditional QTL, accounting for 5.23%-35.36% of the phenotypic variation explained (PVE), which included 7 major and 4 stable QTL, were identified. Meanwhile, 13 conditional QTL, explaining 5.88%-40.35% of PVE, including 5 major and 3 stable QTL, were discovered. Furthermore, four consistent and stable QTL were identified. Finally, eight candidate genes were predicted through RNA-seq and weighted gene co-expression network analysis (WGCNA). Those findings provide a crucial foundation for understanding the genetic mechanisms underlying PH development and facilitate molecular marker-assisted breeding of ideal plant types in foxtail millet.

The Influencing Factors of Nutrition and Diet Health Knowledge Dissemination Using the WeChat Official Account in Health Promotion.

Background: The promotion of a healthy diet via health education is a component of the "Healthy China 2030" plan. However, few studies have reported whether health knowledge about nutrition and diet has gained public attention, and whether it is needed by the public. Methods: The numbers of views, shares, and reads of articles published by the official WeChat account of a hospital in China were accessed. The influence index was obtained via the entropy analysis of these three indices. A questionnaire survey was developed based on the purpose of the study and the conclusion of the content analysis, which conducted to analyze users' requirements for health knowledge and their influencing factors. Moreover, risk factors were explored by logistic regression models. Results: Of the 103 articles considered in this study, four articles in the Top 10 were related to nutrition and diet. The influence index of nutrition and diet knowledge was found to be the highest in the content analysis (p < 0.05). The higher degrees of humor (ß = 0.224, p = 0.027), nutrition and diet articles (ß = 0.776, p = 0.034), and cover articles (ß = 0.312, p = 0.021) have significant influences on the influence index. In total, 581 questionnaires were obtained, and 78.1% of the respondents reported believing that the health knowledge of greatest concern was that related to nutrition and diet. Multivariate logistic regression analyses were conducted to explore the associations between the features of the articles and users reading nutrition and diet knowledge; it was found that gender (female, OR: 4.651, 95%Cl: 2.598, 8.325, and p < 0.001), age (young adult, OR: 0.358, 95%Cl: 0.266, 0.481, and p < 0.001), cancer precaution knowledge (OR: 4.333, 95%Cl: 2.262, 8.299, and p < 0.001), traditional Chinese medicine (OR: 2.121, 95%Cl: 1.064, 4.230, and p = 0.033), the knowledge acquisition approach [circle of friends (OR: 2.586, 95%Cl: 1.373, 4.868, and p = 0.003), social media (OR: 2.183, 95%Cl: 1.204, 3.960, and p = 0.010)), hospitals (OR: 3.194, 95%Cl: 1.793, 5.692, and p < 0.001), television media (OR: 4.348, 95%Cl: 2.341, 8.077, and p < 0.001)], and social media strategies [professionalism and authority (OR: 2.354, 95%Cl: 1.231, 4.505, and p = 0.006)] have statistically significant relationships with users reading nutrition and diet knowledge. Conclusion: Nutrition and diet knowledge could contribute to WeChat user engagement of health information dissemination. Nutrition professionals should improve the scientific popularization ability and effectively use social media for health promotion.

Fine mapping of qPH9, a major quantitative trait locus, responsible for plant height in foxtail millet [Setaria italica (L.) P. Beauv.].

Plant height is vital for crop yield by influencing plant architecture and resistance to lodging. Although lots of quantitative trait loci (QTLs) controlling plant height had been mapped in foxtail millet, their contributions to phenotypic variation were generally small and mapping regions were relatively large, indicating the difficult application in molecular breeding using marker-assisted selection (MAS). In the present paper, a total of 23 QTLs involving in 15 traits were identified via a high-density Bin map containing 3024 Bin markers with an average distance of 0.48 cM through an F2 population. Among them, qPH9, with a large phenotypic variation explained (51.6%) related to plant height, was one of the major QTLs. Furthermore, qPH9 was repeatedly detected in multi-environments under field conditions using two new developed F2 populations from the same F1 plant, and was narrowed down to a smaller interval of 281 kb using 1024 recessive F2 individuals from the same F1 plant. Finally, we found that there was an extremely significant correlation between marker MRI1016 and plant height, and further speculated that Seita.9G088900 and Seita.9G089700 could be key candidates of qPH9. This study laid an important foundation for the cloning of qPH9 and molecular breeding of dwarf varieties via MAS. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01261-w.