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Sweet corn (Zea mays var. rugosa Bonaf.) is a crop with a high economic benefit in tropical and subtropical regions. Heat tolerance analysis and heat-tolerant gene mining are of great significance for breeding heat-resistant varieties. By combining improved genotyping using targeted sequencing (GBTS) with liquid chip (LC) technology, a high-density marker array containing 40 K multiple single polynucleotide polymorphisms (mSNPs) was used to genotype 376 sweet corn inbred lines and their heat-stress tolerance was evaluated in the spring and summer of 2019. In general, plant height, ear height and the number of lateral branches at the first level of the male flowers were reduced by 24.0%, 36.3%, and 19.8%, respectively. High temperatures in the summer accelerated the growth process of the sweet corn, shortening the days to shedding pollen by an average of 21.6% compared to the spring. A genome-wide association study (GWAS) identified 85 significant SNPs distributed on 10 chromosomes. Phenotypes in the spring and summer were associated with the 21 and 15 loci, respectively, and significant phenotypic differences between the two seasons caused by the temperature change were associated with the 49 SNP loci. The seed setting rate (SSR) was more susceptible to heat stress. An annotation analysis identified six candidate genes, which are either heat shock transcription factors (Hsfs) or heat shock proteins (Hsps) in Arabidopsis and rice (Oryza sativa), and these candidate genes were directly and indirectly involved in the heat-resistant response in the sweet corn. The current findings provide genetic resources for improving the heat-stress tolerance of sweet corn by molecular breeding. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) Fusarium ear rot (FER), which is caused by the fungal pathogen Fusarium verticillioides, is a major ear disease affecting maize production in China. Developing resistant maize hybrids is a cost‐effective and environmentally friendly method of reducing yield losses due to FER. Using the nail punch inoculation method, 17 highly resistant and 16 highly susceptible inbred lines were identified in this study, and a large‐scale maize hybrid consisting of 528 F1's was produced using a half‐diallel cross model. The hybrids were inoculated with F. verticillioides in 6 year–location environment combinations during 2020–2022. Our results showed that estimates of genotypic, environmental, and genotype × environment interaction variance components were very significant (p < 0.001). All the crosses generated from highly resistant inbred lines exhibited high kernel resistance, whereas those generated from highly susceptible inbred lines mostly exhibited high susceptibility to FER. Crosses between resistant and susceptible inbred lines showed intermediate resistance to FER. The general combining ability (GCA) effect was greater than the specific combining ability effect across multiple environments, indicating that the inheritance of FER resistance was mainly influenced by additive genetic effects. The correlation coefficient between the expected GCA value and hybrid resistance was 0.789, whereas that between the mid‐parent value and hybrid resistance was only 0.644. Inbred performance per se and their corresponding hybrids across multiple environments were significantly correlated (r = 0.823). However, no relationship was observed between the FER resistance of F1's and that of their parental heterotic groups. Core Ideas: In breeding, selecting parents with Fusarium ear rot (FER) resistance is more crucial than selecting the hybrids themselves.The additive effect is the main genetic component of ear rot in maize, whereas the non‐additive effect is minor.Additional inoculation tests for FER resistance are required for specific hybrid combinations.Hybrid resistance can be inferred based on the general combining ability of parental inbred lines.The additive effects of resistance genes in highly inbred lines are minor. [ABSTRACT FROM AUTHOR]

In this paper, a broadband(12-18G) low-noise amplifier (LNA) using 65-nm CMOS technology for satellite communication is presented. This LNA was designed in a cascode common source with inductive degeneration topology. In addition, the bulk isolation technique is employed to make the proposed LNA have a higher gain. Furthermore, a two-stage cascaded configuration combined with inductive parallel peaking technology is utilized to make the LNA achieve a wide operating band. For validation, we design this LNA in a 65nm CMOS technology. The simulated results show that S21 of 17.7dB ± 0.5dB, the input/output return loss of -10dB to -33dB and -12dB to -23dB, respectively. It offers the minimum noise figure (NF) performance of 3.33dB, reverse isolation(S12) better than 60dB, and third-order input point (IIP3) of -22.8 dBm obtained over the band of interest. Excluding the output buffer stage, the LNA is consuming 5.1 mW at a supply voltage of 0.8V and its layout area occupies 0.205 mm2. [ABSTRACT FROM AUTHOR]

Fusarium ear rot (FER) is a common disease of maize that can seriously affect the yield and quality of maize. Resistance to FER is highly quantitative, largely under polygenic control with minor effects, and strongly influenced by environmental conditions. In this study, two F2:3 populations with 220 and 152 lines were developed from PHW43 × 8107 (PH81) and Zong31 × DTMA165 (ZODT) for QTL mapping and genomic selection (GS). Artificial inoculation was performed to evaluate FER resistance in four environments, Gongzhuling 2019, Shunyi 2019, Xinxiang 2019, and Xinxiang 2020. For both populations, we constructed a relatively high-density linkage map. Each F2:3 population showed a lower average FER severity than the natural population tested before. Significant genotypic variance, environment variance, and genotype × environment interaction variance were detected in both populations by combined ANOVA analysis. The combined broad-sense heritability of the FER severity was estimated as 0.60 and 0.67 in PH81 and ZODT, respectively. In PH81, seven QTL were identified on chromosomes 1, 4, 6, 7, and 10, four of which were detected in Xinxiang 2019 environment together explaining 24.15% of the total phenotypic variation. The QTL qPBLUE–7–1 on bin7.01 explaining the highest phenotypic variation (6.14–8.60%) was consistently identified across Xinxiang 2019 environment and the best linear unbiased estimators. Eight QTL were identified in ZOTD, explaining 7.11% (qZBLUE–6–1) to 13.29% (qZS19–10–1) of phenotypic variation. Two candidate genes were identified in bin 6.05, of which GRMZM2G066153 encodes an enzyme involving the defense of pathogens in many plants. Genomic best linear unbiased prediction (GBLUP) showed that 500 SNP markers were enough for F2:3 populations to achieve reasonably good prediction. The prediction accuracy in F2:3 populations could be improved by integrating QTL information into the GBLUP model and by using the extended GBLUP model with additive and dominance effects included. [ABSTRACT FROM AUTHOR]

In order to find out the cause of unqualified corrosion resistance of triangle arm parts on automotive chassis, the surface states of the front and back sides of triangular arm after welding, as well as the surface morphologies and elemental composition before and after phosphating were compared, and a simulated welding test was also conducted. It was found that the too high amount of oil coated on the surface of steel plate was the main cause. The problem was solved by reducing the oil amount to 0.3-0.5 g/m². [ABSTRACT FROM AUTHOR]