Breaking dormancy and germination of wild pear (Pyrus spp) seeds

Document Type : Research Paper

Authors

1 Azad University, Jahrom Branch

2 Research Center for Agriculture and Natural Resources of Fars Province

Abstract

Several species of wild pear are native to Fars province in Iran, but little information about different aspects of their growth habit is available.  Investigation on breaking seed dormancy and germination is needed for propagation of wild pear species as a rootstock for common pear and for afforestation. This research was carried out to study the methods of breaking dormancy, germination and seedling growth of different genotypes of three wild pear species including: Pyrus syriaca, Pyrus glabra and a probable natural hybrid of Pyrus syriaca ´ Pyrus glabra.  Seeds of Pyrus glabra (genotype 11) were used for test of viability, excised embryos and chemical scarification.  Seed viability was tested using tetrazolium (1%) and results showed that seeds were 100% viable. Based on the results of excised embryo test, germination percentage of stratified excised embryos was more than that of non stratified embryos.  Chemical scarification with concentrated sulfuric acid did not affect breaking dormancy of seeds. Results of seed stratification for 0, 15, 30, 45 and 60 days indicated that 60 days stratification was the best treatment for removing dormancy in wild pear species seeds. Seeds originated from different trees (each tree considered as a genotype) of wild pear species showed different responses with regard to stratification period.  Seedling growth of Pyrus glabra was affected by stratification period and 45 days stratification was more effective on hypocotyl length and seedling fresh weight than the other treatments.  It could be concluded that stratification for 60 days was the best treatment for breaking dormancy and seed germination of wild pear species studied in this research.

Keywords

References

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