Knockout of the lignin pathway gene BnF5H decreases the S/G lignin compositional ratio and improves Sclerotinia sclerotiorum resistance in Brassica napus.

Ferulate-5-hydroxylase is a key enzyme involved in the conversion of the guaiacyl monolignol to the syringyl monolignol in angiosperms. The monolignol ratio has been proposed to affect biomass recalcitrance and the resistance to plant disease. Stem rot caused by the fungus Sclerotinia sclerotiorum in Brassica napus causes severe losses in its production. To date, there is no information about the effect of the lignin monomer ratio on the resistance to S. sclerotiorum in B. napus. Four dominantly expressed ferulate-5-hydroxylase genes were concertedly knocked out by CRISPR/Cas9 in B. napus, and three mutant lines were generated. The S/G lignin compositional ratio was decreased compared to that of the wild type based on the results of Mӓule staining and 2D-NMR profiling in KO-7. The resistance to S. sclerotiorum in stems and leaves increased for the three f5h mutant lines compared with WT. Furthermore, we found that the stem strength of f5h mutant lines was significantly increased. Overall, we demonstrate for the first time that decreasing the S/G ratio by knocking out of the F5H gene improves S. sclerotiorum resistance in B. napus and increases stem strength.

Social protection and the level and inequality of child mortality in 101 low- and middle-income countries: A statistical modelling analysis.

BACKGROUND: Expanding social protection programme is a major target of the Sustainable Development Goals. Previous studies provided evidence for the relationship of social protection programme to greater use of health services and some improved health outcomes for children. Yet, its impact on child mortality has not been clearly revealed. In this study, we examined the association between social protection programmes and child mortality. METHODS: We obtained child mortality data from 379 nationally representative surveys involving 101 low- and middle-income countries (LMICs). We included five child mortality outcomes in the study, which were neonatal mortality rate (NMR), post-neonatal mortality rate (PMR), childhood mortality rate (CMR), infant mortality rate (IMR), and under-5 mortality rate (U5MR). We extracted data on social protection programmes from multiple data sources (eg, Atlas of Social Protection Indicators of Resilience and Equity). Social protection and labour programme (SPL) was the major type of social protection we included. We also included four subtypes of SPL - social assistance, cash transfer, social insurance, and labour market protection. Both unadjusted and adjusted regressions were conducted to measure the associations between characteristics of social protection programmes and child mortality, as well as inequalities in child mortality. RESULTS: Among the 101 countries, the median coverage rate of SPL was 28.5%, with an interquartile range between 6.5% and 55.2%. Using the adjusted model, we found a one-percentage-point increase in SPL coverage is associated with a reduction of 0.09 (95% confidence interval (CI) = 0.04, 0.14) per 1000 live births in NMR, 0.11 (95% CI = 0.04, 0.18) in PMR, and 0.25 (95% CI = 0.11, 0.38) in CMR. Social assistance programme was the only subtype of SPL to be significantly associated with lower mortality rates. A higher SPL coverage was associated with better equity in child mortality - as the coverage of SPL increased by one percentage point, the concentration index of CMR would increase by 0.08 (95% CI = 0.03, 0.13) in the adjusted model, suggesting an improvement in equity. CONCLUSIONS: The strong association between social protection programme and child mortality suggests that to achieve the SDG targets of universal social protection and to reduce child mortality, LMICs shall consider prioritizing the expansion of social protection programmes.

Integrating GWAS, linkage mapping and gene expression analyses reveals the genetic control of growth period traits in rapeseed (Brassica napus L.).

BACKGROUND: Brassica napus is one of the most important oilseed crops, and also an important biofuel plant due to its low air pollution and renewability. Growth period are important traits that affect yield and are crucial for its adaptation to different environments in B. napus. RESULTS: To elucidate the genetic basis of growth period traits, genome-wide association analysis (GWAS) and linkage mapping were employed to detect the quantitative trait loci (QTL) for days to initial flowering (DIF), days to final flowering (DFF), flowering period (FP), maturity time (MT), and whole growth period (GP). A total of 146 SNPs were identified by association mapping, and 83 QTLs were identified by linkage mapping using the RIL population. Among these QTLs, 19 were pleiotropic SNPs related to multiple traits, and six (q18DFF.A03-2, q18MT.A03-2, q17DFF.A05-1, q18FP.C04, q17DIF.C05 and q17GP.C09) were consistently detected using both mapping methods. Additionally, we performed RNA sequencing to analyze the differential expression of gene (DEG) transcripts between early- and late-flowering lines selected from the RIL population, and the DEGs were integrated with association mapping and linkage analysis to confirm their roles in the growth period. Consequently, 12 candidate genes associated with growth period traits were identified in B. napus. Among these genes, seven have polymorphic sites in the coding sequence and the upstream 2-kb sequence based on the resequencing data. The haplotype BnaSOC1.A05-Haplb and BnaLNK2.C06-Hapla showed more favorable phenotypic traits. CONCLUSIONS: The candidate genes identified in this study will contribute to our genetic understanding of growth period traits and can be used as targets for target mutations or marker-assisted breeding for rapeseed adapted to different environments.