Micromorphological study on the seeds of wild species Pyrus (Rosaceae) in Iran and their taxonomic implication

Polyploid plants usually exhibit broader leaves, thicker stems, bigger flowers and fruits, dwarfing stature, as well improved biotic abiotic resistance. Therefore, increasing the polyploidy is one of most important strategies used in plant breeding. Here, we reported successful induction tetraploids two pear varieties, ‘duli’ (Pyrus betulaefolia), a wildtype for rootstocks grafting, ‘Xinli No.7...

The draft genome sequence of Xylella fastidiosa pear leaf scorch strain PLS229, isolated from the pear cultivar Hengshan (Pyrus pyrifolia) in Taiwan, is reported here. The bacterium has a genome size of 2,733,013 bp, with a G+C content of 53.1%. The PLS229 genome was annotated and has 3,259 open reading frames and 50 RNA genes.

Two new species belonging to the family Stigmaeidae, Cheylostigmaeus tarae sp. nov. and Stigmaeus delaramae sp. nov., are described from specimens collected from soil and litter under pear trees, Pyrus communis L. (Rosaceae) in Iran. A key to all Iranian species of the genera Cheylostigmaeus (male) and Stigmaeus (female) are provided. 

'Jin Zhui' is a spontaneous self-compatible mutant of 'Ya Li' (Pyrus bretschneideri Rehd. S21S34 ), the latter displaying a typical S-RNase-based gametophytic self-incompatibility (GSI). The pollen-part mutation (PPM) of 'Jin Zhui' might be due to a natural mutation in the pollen-S gene (S34 haplotype). However, the molecular mechanisms behind these phenotypic changes are still unclear. In this...

Since several Asian pear species are considered to be potential source of fire blight resistance, we crossed ‘Doyenné du Comice’, the susceptible European cultivar, with four Asian pear species. The aim of the study was to establish the level of resistance of each genotype and the mode of transmission of fire blight resistance to each F1 full-sib progeny. The best sources of resistance were P. ...

The number of isoperoxidases and the intensity of certain isozymes increased with increasing periods of stratification of pear (Pyrus communis cv. Bartlett) embryos. The presence of GA(3) or kinetin during stratification enhanced the activity of certain isoperoxidases, and these enhancements were blocked in the presence of ABA which by itself had an inhibitory effect. Enhancement in isoperoxida...

In this study, zinc oxide nanostructures (ZnO NS) were synthesized using Pyrus pyrifolia fruit extract. Biophysical characterization results confirmed that the materials are crystalline wurtzite ZnO structures. Field emission scanning electron microscopy (FESEM) revealed NS cubical, and sizes range 20–80 nm. Transmission (TEM) XRD a crystal lattice spacing of 0.23 nm (101) plane on NS. UV-Visib...