Self-incompatibility alleles in Iranian pear cultivars

Transcriptome Analysis of the Late-Acting Self-Incompatibility Associated with RNase T2 Family in Camellia oleifera

The Camellia oil tree (Camellia oleifera Abel.) is an important nonwood forest species in China, and the majority of its cultivars are late-acting self-incompatibility (LSI) types. Although several studies have examined the mechanism of LSI, the process is quite complicated and unclear. In this study, pollen tube growth and fruit setting of two Camellia oil tree cultivars Huashuo (HS) and Huajin (HJ) were investigated after non and self-pollination, and transcriptomic analysis of the ovaries was performed 48 h after self-pollination to identify the potential genes implicated in the LSI of Camellia oil trees. The results showed that the fruit set of HS was significantly higher than that of HJ after self-pollination. Transcriptomic analysis revealed that plant hormone signal transduction, the phosphatidylinositol signaling system, ATP-binding cassette (ABC) transporters, reactive oxygen species (ROS) metabolism, and Ca2+ signaling were mainly contributed in the LSI of reaction of Camellia oil tree. Moreover, nine RNase T2 genes were identified from the transcriptome analysis, which also showed that CoRNase7 participated in the self-incompatibility reaction in HS. Based on phylogenetic analysis, CoRNase6 was closely related to S-RNase from coffee, and CoRNase7 and CoRNase8 were closely related to S-RNase from Camellia sinensis. The 9 RNase T2 genes successfully produced proteins in prokaryotes. Subcellular localization indicated that CoRNase1 and CoRNase5 were cytoplasmic proteins, while CoRNase7 was a plasma membrane protein. These results screened the main metabolic pathways closely related to LSI in Camellia oil tree, and SI signal transduction might be regulated by a large molecular regulatory network. The discovery of T2 RNases provided evidence that Camellia oil tree might be under RNase-based gametophytic self-incompatibility.

Phenotypic assessment of pear varieties in mutual pollination

The self-fertility and cross-fertility of pear varieties have been studied in the conditions of the of the Krasnodar region. It was established that most of the not varieties are self-fertile. The varieties are distinguished: Ladozhskaya, Malyshka and Talgar beauty, with partial self-fertility, in which a low percentage of fruit set and its fluctuation over the years are noted. Based on the pollination performed and the analysis carried out, good and acceptable pollinators for promising pear varieties were selected. It has been established that in order to form full-fledged seeds in the fruit of the pear, a full cross-pollination with good pollinators is necessary. The possibilities of individual varieties (a high percentage of fruit tying) with mutual pollination are presented. The analysis of the negative influence of technogenic factors during flowering on the inter-pollination of varieties has been carried out. Cross-pollinated varieties have a narrow selective ability to pollinate varieties, which varies over the years and depends on the growing conditions. Proved the need, when laying gardens correctly choose varieties-pollinators in order to increase the yield of varieties. According to the research results, a self-fertile variety Iyulskaya early was identified. The best pollinators were selected for promising pear varieties for the conditions of the Kuban.