(1) Background: the species of Corylus have sporophytic type of self-incompatibility. Several genes related to recognition reaction between pollen and stigma have been identified in hazelnuts. To better understand the self-incompatibility (SI) response, we screened the suitable reference genes by using quantitative real-time reverse transcription PCR (qRT-PCR) analysis in hazelnut for the first time. (2) Methods: the major cultivar “Dawei” was used as material. A total of 12 candidate genes were identified and their expression profiles were compared among different tissues and in response to various treatments (different times after self- and cross-pollination) by RT-qPCR. The expression stability of these 12 candidate reference genes was evaluated using geNorm, NormFinder, BestKeeper, Delta Ct, and RefFinder programs. (3) Results: the comprehensive ranking of RefFinder indicated that ChaActin, VvActin,ChaUBQ14, and ChaEF1-α were the most suitable reference genes. According to the stability analysis of 12 candidate reference genes for each sample group based on four software packages, ChaActin and ChaEF1-α were most stable in different times after self-pollination and 4 h after self- and cross-pollination, respectively. To further validate the suitability of the reference genes identified in this study, CavPrx, which the expression profiles in Corylus have been reported, was quantified by using ChaActin and ChaEF1-α as reference genes. (4) Conclusions: our study of reference genes selection in hazelnut shows that the two reference genes, ChaActin and ChaEF1-α, are suitable for the evaluation of gene expression, and can be used for the analysis of pollen-pistil interaction in Corylus. The results supply a reliable foundation for accurate gene quantifications in Corylus species, which will facilitate the studies related to the reproductive biology in Corylus.

Background: Living covers are an important management measure for orchards in China, which has a certain influence on soil properties, microorganisms and micro-ecological environment. However, there are few studies on the effects of living covers on the soil changes in hazelnut orchard. In this study, we compared living cover treatment by Vulpia myuros and no cover treatment, and analyzed the changes on the soil properties, microorganisms and microbial function by using high-throughput ITS rDNA and 16S rRNA gene Illumina sequencing. Results: The consequences demonstrated that the total organic carbon content of living cover treatment in the 20-40 cm soils increased by 32.87 % and 14.82 % respectively in May and July compared with no cover treatment, and living cover treatment by Vulpia myuros can also significantly increased the contents of total phosphorus (TP), total nitrogen (TN), available phosphorus (AP) and available potassium (AK) in the soil samples. Moreover, the influence of seasons is not as significant as that of soil depth. The living cover treatment significantly improved the soil enzymes activity levels. Among the four kind of soil enzymes, the soil invertase activity of living cover treatment was 50.94 % greater than that of no cover treatment in 0-20 cm soils and 52.17 % in 20-40 cm soils in May. The consequences demonstrated that Ascomycota, Mortierellomycota and Basidiomycota were the dominant fungal phylum in all samples, while Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Chloroflexi were the dominant bacterial phylum, but different treatments impacted the composition of fungal and bacterial communities. Principal component analysis (PCA) showed that living cover with Vulpia myuros significantly changed the soil fungal community structure whereas the bacterial community structure may be more sensitive to seasonal changes. At the microbial functional level, the pathotrophs, saprotrophs and symbiotrophs accounted for approximately 36.69 %, 49.80 % and 2.59 % of no cover treatment fungal OTUs respectively whereas in living cover treatment was 19.76 %, 41.51 % and 6.89 %. Conclusions: According to this study, we believe that the living cover with Vulpia myuros has a favorable regulating influence on soil properties, microbial community and microbial function, and can be considered as a management measure for hazelnut orchards management.