Abstract
(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.
Highlights
Hazelnut (Corylus), a member of the birch family (Betulaceae) in the order Fagales, is one of the most important nut crops and a woody oil plant, with high economic and nutritional value
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
According to the filtering criteria (False Discovery Rate (FDR) < 0.01 and Log2 ratio between −1 and 1) mentioned in the Materials and Methods, three candidate reference genes were selected from the transcriptome database, based on expression stability
Summary
Hazelnut (Corylus), a member of the birch family (Betulaceae) in the order Fagales, is one of the most important nut crops and a woody oil plant, with high economic and nutritional value. Around 25 species of Corylus have been described by taxonomists, among which 13 are widely-recognized [1,2]. The various species of hazelnut are primarily distributed across the temperate zones of the Northern Hemisphere [3], with Asia, Europe, and North America. Only some cultivars of European hazelnut (C. avellana) have been commercialized [4,5]. Eight species and two varieties of Corylus are native to China, and are widely-distributed across 24 provinces. The main commercial cultivars are several types of Ping’ou hybrid hazelnuts, obtained by artificial interspecific hybridization of the Ping hazelnut (C. heterophylla) with European hazelnut [6,7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
