A preliminary study on pollen compatibility of some hazelnut cultivars in Iran

Pollen incompatibility is a major problem among hazelnut cultivars and can result in considerable crop loss in hazelnut orchards. Thus, identifying the level of self-compatibility of a cultivar and compatibility between cultivars are crucial aspects to selecting the proper pollenizers. Controlled self- and cross-pollinations were carried out in three local and four imported hazelnut cultivars. Based on cluster set, partial self-compatibility was found in cultivars Pashmine and Shastak, and complete self-compatibility in ‘Tabestane’. The best pollenizers for the cultivars Pashmine, Tabestane, Shastak, Barcelona, Segorbe, Daviana and Merveille were Segorbe, Barcelona, Segorbe, Shastak, Shastak, Pashmine and, Pashmine, respectively

RNA-seq analysis and reconstruction of gene networks involved in response to salinity stress in quinoa (cv. Titicaca)

Abstract To better understand the mechanisms involved in salinity stress, the adaptability of quinoa cv. Titicaca—a halophytic plant—was investigated at the transcriptome level under saline and non-saline conditions. RNA-sequencing analysis of leaf tissue at the four-leaf stage by Illumina paired—end method was used to compare salt stress treatment (four days after stress at 13.8 dsm−1) and control. Among the obtained 30,846,354 transcripts sequenced, 30,303 differentially expressed genes from the control and stress treatment samples were identified, with 3363 genes expressed ≥ 2 and false discovery rate (FDR) of < 0.001. Six differential expression genes were then selected and qRT-PCR was used to confirm the RNA-seq results. Some of the genes (Include; CML39, CBSX5, TRX1, GRXC9, SnRKγ1 and BAG6) and signaling pathways discussed in this paper not been previously studied in quinoa. Genes with ≥ 2 were used to design the gene interaction network using Cytoscape software, and AgriGO software and STRING database were used for gene ontology. The results led to the identification of 14 key genes involved in salt stress. The most effective hub genes involved in salt tolerance were the heat shock protein gene family. The transcription factors that showed a significant increase in expression under stress conditions mainly belonged to the WRKY, bZIP and MYB families. Ontology analysis of salt stress-responsive genes and hub genes revealed that metabolic pathways, binding, cellular processes and cellular anatomical entity are among the most effective processes involved in salt stress

The RNA-seq transcriptomic analysis reveals genes mediating salt tolerance through rapid triggering of ion transporters in a mutant barley.

Considering the complex nature of salinity tolerance mechanisms, the use of isogenic lines or mutants possessing the same genetic background albeit different tolerance to salinity is a suitable method for reduction of analytical complexity to study these mechanisms. In the present study, whole transcriptome analysis was evaluated using RNA-seq method between a salt-tolerant mutant line "M4-73-30" and its wild-type "Zarjou" cultivar at seedling stage after six hours of exposure to salt stress (300 mM NaCl). Transcriptome sequencing yielded 20 million reads for each genotype. A total number of 7116 transcripts with differential expression were identified, 1586 and 1479 of which were obtained with significantly increased expression in the mutant and the wild-type, respectively. In addition, the families of WRKY, ERF, AP2/EREBP, NAC, CTR/DRE, AP2/ERF, MAD, MIKC, HSF, and bZIP were identified as the important transcription factors with specific expression in the mutant genotype. The RNA-seq results were confirmed at several time points using qRT-PCR for some important salt-responsive genes. In general, the results revealed that the mutant accumulated higher levels of sodium ion in the root and decreased its transfer to the shoot. Also, the mutant increased the amount of potassium ion leading to the maintenance a high ratio [K+]/[Na+] in the shoot compared to its wild-type via fast stomata closure and consequently transpiration reduction under the salt stress. Moreover, a reduction in photosynthesis and respiration was observed in the mutant, resulting in utilization of the stored energy and the carbon for maintaining the plant tissues, which is considered as a mechanism of salt tolerance in plants. Up-regulation of catalase, peroxidase, and ascorbate peroxidase genes has resulted in higher accumulation of H2O2 in the wild-type compared to the mutant. Therefore, the wild-type initiated rapid ROS signals which led to less oxidative scavenging in comparison with the mutant. The mutant increased expression in the ion transporters and the channels related to the salinity to maintain the ion homeostasis. In overall, the results demonstrated that the mutant responded better to the salt stress under both osmotic and ionic stress phases and lower damage was observed in the mutant compared to its wild-type under the salt stress