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Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight (TGW) in wheat (Triticum aestivum L.). However, no mutations have been identified within the gene to test this association. The effects of TaSus1 on grain number per spike (GNS) also are largely unknown. Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike (FSN). In the present study, we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing. The triple mutants displayed lower FSN, GNS, grain number per spikelet (GNST), and TGW than wild-type plants. In 306 hexaploid wheat accessions, two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS. Introgression of the two alleles into a wheat genetic background confirmed their effects. The alleles differed in geographical distribution among the accessions.

Yield-related traits have higher heritability and lower genotype-by-environment interaction, making them more suitable for genetic studies in comparison with the yield per se. Different populations have been developed and employed in QTL mapping; however, the use of reciprocal SSSLs is limited. In this study, three kinds of bi-parental populations were used to investigate the stable and novel QTLs on six yield-related traits, i.e., plant height (PH), heading date (HD), thousand-grain weight (TGW), effective tiller number (ETN), number of spikelets per panicle (NSP), and seed set percentage (SS). Two parental lines, i.e., japonica Asominori and indica IR24, their recombinant inbred lines (RILs), and reciprocal single-segment substitution lines (SSSLs), i.e., AIS and IAS, were genotyped by SSR markers and phenotyped in four environments with two replications. Broad-sense heritability of the six traits ranged from 0.67 to 0.94, indicating their suitability for QTL mapping. In the RIL population, 18 stable QTLs were identified for the six traits, 4 for PH, 6 for HD, 5 for TGW, and 1 each for ETN, NSP, and SS. Eight of them were validated by the AIS and IAS populations. The results indicated that the allele from IR24 increased PH, and the alternative allele from Asominori reduced PH at qPH3-1. AIS18, AIS19, and AIS20 were identified to be the donor parents which can be used to increase PH in japonica rice; on the other hand, IAS14 and IAS15 can be used to reduce PH in indica rice. The allele from IR24 delayed HD, and the alternative allele reduced HD at qHD3-1. AIS14 and AIS15 were identified to be the donor parents which can be used to delay HD in japonica rice; IAS13 and IAS14 can be used to reduce HD in indica rice. Reciprocal SSSLs not only are the ideal genetic materials for QTL validation, but also provide the opportunity for fine mapping and gene cloning of the validated QTLs.

Abstract Background Large-scale genotype–phenotype association studies of crop germplasm are important for identifying alleles associated with favorable traits. The limited number of single-nucleotide polymorphisms (SNPs) in most wheat genome-wide association studies (GWASs) restricts their power to detect marker-trait associations. Additionally, only a few genes regulating grain number per spikelet have been reported due to sensitivity of this trait to variable environments. Results We perform a large-scale GWAS using approximately 40 million filtered SNPs for 27 spike morphology traits. We detect 132,086 significant marker-trait associations and the associated SNP markers are located within 590 associated peaks. We detect additional and stronger peaks by dividing spike morphology into sub-traits relative to GWAS results of spike morphology traits. We propose that the genetic dissection of spike morphology is a powerful strategy to detect signals for grain yield traits in wheat. The GWAS results reveal that TaSPL17 positively controls grain size and number by regulating spikelet and floret meristem development, which in turn leads to enhanced grain yield per plant. The haplotypes at TaSPL17 indicate geographical differentiation, domestication effects, and breeding selection. Conclusion Our study provides valuable resources for genetic improvement of spike morphology and a fast-forward genetic solution for candidate gene detection and cloning in wheat.

Abstract Background Plant architecture associated with increased grain yield and adaptation to the local environments is selected during wheat (Triticum aestivum) breeding. The internode length of individual stems and tiller length of individual plants are important for the determination of plant architecture. However, few studies have explored the genetic basis of these traits. Results Here, we conduct a genome-wide association study (GWAS) to dissect the genetic basis of geographical differentiation of these traits in 306 worldwide wheat accessions including both landraces and traditional varieties. We determine the changes of haplotypes for the associated genomic regions in frequency in 831 wheat accessions that are either introduced from other countries or developed in China from last two decades. We identify 83 loci that are associated with one trait, while the remaining 247 loci are pleiotropic. We also find 163 associated loci are under strong selective sweep. GWAS results demonstrate independent regulation of internode length of individual stems and consistent regulation of tiller length of individual plants. This makes it possible to obtain ideal haplotype combinations of the length of four internodes. We also find that the geographical distribution of the haplotypes explains the observed differences in internode length among the worldwide wheat accessions. Conclusion This study provides insights into the genetic basis of plant architecture. It will facilitate gene functional analysis and molecular design of plant architecture for breeding.

Agricultural white pollution is a pressing concern in China. However, the efficiency and rationality of the government’s subsidies for mulch film management remain ambiguous. To formulate reasonable policies for mulch film management and optimize fiscal resource allocation, the study employs cost–benefit analysis to evaluate the economic performance of mulch film management. Two environmentally friendly measures being primarily proposed in China, namely the application of thicker mulch film (hereinafter referred to as thicker film) and the substitution of biodegradable mulch film (hereinafter referred to as biodegradable film), are selected for analysis, with conventional mulch film (hereinafter referred to as conventional film) serving as the benchmark for comparison. Primary data obtained through field surveys, supplemented by secondary data from national statistics, industry reports, and literature reviews, are used for the study. Results show that thicker film application is cost-effective, with a net benefit of CNY 3208.8/ha (USD 449.2/ha; 1 CNY = 0.14 USD), which is CNY 253.8/ha (USD 35.5/ha) higher than that of conventional film. The net benefit for biodegradable film application is lower than that for conventional film, at CNY 2244.6/ha (USD 314.2/ha). The results reveal the significant potential of promoting the use of thicker film due to its recycling and economic advantages. Findings imply that the further promotion of its use lies in improving farmers’ cognition and optimizing subsidy dimensions to allocate government financial resources more effectively. On the contrary, biodegradable film utilization is unprofitable and relies on continuous external subsidies. The government can optimize the subsidy standard based on the cost–benefit performance of different mulch films applied and provide incentives to promote cost reductions and efficiency increases. Further analysis indicates that sustainable mulch film management entails developing mechanisms to internalize the external benefits of management and innovating a new governance landscape.

Evaluation of farmers’ willingness to participate (WTPP) and willingness to pay (WTP) for the centralized mode provision (CMP) of rural domestic sewage treatment (RDST) is imperative to improve the rural environment as well as to alleviate government financial pressures. This study adopted the contingent valuation method as well as face-to-face interview questionnaires to assess rural residents’ provision mode preferences, WTPP, and WTP for the CMP of RDST in China. Based on 761 samples collected from Shandong, Jilin, and Gansu provinces of China, we applied econometric models to estimate farmers’ WTPP and WTP for the CMP of RDST and explore the potential influencing factors, respectively. Results show that 1) 81.87% of the farmers would be willing to contribute to CMP of RDST; 2) farmers’ perceptions of the necessity of RDST, pollution of rural domestic sewage, and government propaganda significantly and positively affect their WTP; and 3) the expected WTP for CMP of RDST with the total respondents and the respondents with positive WTPP were estimated to be 7.59 USD/year and 10.10 USD/year (for a total of 20 years), accounting for 16.28 and 21.65% of construction costs, respectively. Based on these outcomes, it could be further estimated that the aggregate value was between 179.05 million USD/year and 238.26 million USD/year which implied that the farmers’ WTP may be a potentially non-negligible funding source for the CMP of RDST. The enhancement of environmental awareness of farmers and strengthening of propaganda should be the next priority of the Chinese government. Priority should also be assigned to villages closer to towns when the government formulates relevant strategies and policies. The results of this study provide references for policy formulation related to broadening the funding sources in RDST and exploring farmer payment mechanisms and implications for other developing countries.

During the COVID-19 pandemic, food waste caused by excessive hoarding has accounted a large proportion of the total food waste in urban Chinese households, which indicates that reducing food hoarding has become key to managing household food waste. This study therefore explored the behavioral mechanisms underlying excessive food hoarding among citizens. Based on a sample set of 511 respondents surveyed in Beijing, Hefei, and Guiyang in July 2022, a PLS-SEM model was conducted using SmartPLS 3.0 software to simulate the decision-making process of food hoarding. The following results were found. First, among the households with hoarding, 66.37% had some degree of food waste. Second, hoarding preference was the direct predictor of hoarding behavior, which means that hoarding behavior can be effectively controlled by regulating preferences. Third, group influence including homology consistency and social network support, as well as psychological panic, both enhanced citizens’ hoarding preference and induced hoarding behavior. Therefore, it is necessary to weaken group influence and try to help citizens overcome panic. Finally, food supply information release can not only alleviate citizens’ psychological panic and weaken group influence, but also block the transformation of preference into behavior. The above results are of great importance for the design of management policies for food waste caused by irrational hoarding during the pandemic.

The Chinese government has implemented a homestead withdrawal policy to improve the efficiency of rural construction land use. The compensation for rural homestead withdrawal (CRHW) is crucial to the reconstruction and sustainable development of farmers’ livelihoods. This paper analyzed the response mechanisms of farmers’ livelihoods to the CRHW with the combined application of the logistic regression, the mediation effect model, and the moderating effect model. The results indicated that CRHW had a significant positive impact on the sustainable livelihoods of rural households, mainly by improving the physical capital and social capital. In addition, adaptability and livelihood diversity played intermediary and regulatory roles in the positive impacts of the CRHW on sustainable livelihoods, respectively. The conclusions may provide insight into the demand for more reasonable compensation policies to ensure the sustainability of farmers’ livelihoods.

This study aims to explore the clinical significance of C-reactive protein, leukocyte and immunoglobulin in the diagnosis and treatment of infantile pneumonia at acute stage. From January to December 2018, a total of 124 children with pneumonia and healthy children admitted to our hospital were selected as study objects. Among them, 62 children diagnosed with bacterial pneumonia were categorized as the study group, and 62 healthy children who came for physical examination were classified as the control group. The levels of C-reactive protein (CRP), white blood cell (WBC) and immunoglobulin (IgA, IgM and IgG) were observed and compared in the two groups. In this study, higher levels of CRP, IgM, IgG and WBC, along with lower level of IgA were observed in the study group as compared with that in the control group. In the study group, the levels of CRP, IgM, IgG and WBC were lower, but the IgA level was higher in children with mild pneumonia than those with severe pneumonia. After treatment, the levels of CRP, IgM, IgG and WBC were decreased but IgA level was increased after treatment compared with before treatment. In particular, the levels of CRP, WBC, IgA, IgM and IgG in the study group after treatment were restored to comparable levels compared with the control group. Therefore, C-reactive protein, leukocyte and immunoglobulin can be used to determine the diagnosis, condition and outcome of children with pneumonia in the acute stage. This study can provide guidance for clinical diagnosis and treatment of infantile pneumonia based on the alterations of these indicators. [ABSTRACT FROM AUTHOR]