Centre of Pear Engineering Technology Research of Nanjing Agricultural University was founded in 2006. The center is affiliated to the State Key Laboratory of Crop Genetics and Germplasm Enhancement. In 2015, the center was approved as National Pear Improvement Center Nanjing Subcenter. In 2019, the center was approved as Jiangsu Pear Engineering Technology Research Center.
Professor Shaoling Zhang is the chief scientist of National Pear-Industry Research System, is the director of this center. The main research directions of this center include: Evaluation and Innovation of Pear Resource, Genomics and Bioinformatics of Pear, Reproduction Physiology and Cell Biology, Fruit Quality and Regulation Mechanisms.
1.Evaluation and Innovation of Pear Resource
More than 1,000 pear resources from home and abroad have been collected and preserved in our center. Over 50 important agronomic traits have been evaluated systematically, and the fingerprint of these resources have been also constructed. Meanwhile, we are interested in developing new resources and breeding new cultivars with elite traits, such as early maturity, disease resistance, high fruit quality, self-pollination, red-color and other special characteristics. To date, we have nurtured more than 80,000 progenies from 100 hybrid populations, and innovated more than 50 new resources as cultivar candidates. Altogether, 6 new pear cultivars bred by our center have been approved and released publicly. In addition, high density linkage map has been constructed, and QTL loci related to skin color, content of stone cells, sugar and acid have been localized. Consequently, molecular markers tightly linked to these traits have been developed for the marker assisted selection in the cross breeding, and a total of 12 national patents have been authorized.
2.Genomics and Bioinformatics of Pear
Leading by our center, 60 researchers from China, USA and Japan have sequenced and released the first pear genome in the world. In this project, a length of 512.0 Mb sequence of ‘Dangshansuli’ was assembled, and more than 4,2000 functional genes were annotated. Specifically, the unique pear gene families and genes related to the stone cells and other traits of fruit have been analyzed. It firstly revealed that the 17 pear chromosomes are formed through whole genome duplication, chromosome recombination and lost event, and the high heterozygosity of pear genome has also been illustrated. Based on the whole genome sequence of pear, several new research fields have been developed in our center, such as the functional genomics, comparative genomics, and bioinformatics. World widely, we have constructed the pear genetic linkage map with highest density using the SNP and SSR markers developed from the whole genome sequence. Meanwhile, we have constructed the first public professional pear genome website (http:// peargenome.njau.edu.cn), which has been widely used by researchers from 26 countries, and has been widely concerned and well appraised by domestic and foreign colleagues. In recently, more than 20 SCI papers in this filed were published.
3.Reproduction Physiology and Cell Biology
We are the earliest to study the interaction between pollen and pistil in pear around the world. Based on the result obtained over the past twenty years, we proposed a theory that inhibition of self-incompatibility pear pollen tube growth is due to the products of self -incompatibility gene (S gene). Furthermore, we have clarity that the phenomenon of programmed cell death occurred in the self-incompatibility pollen. In other hand, we have detected the roles of ion channels in controlling pollen tube transport and release gamete. We have identified and characterized a hyperpolarization-activated Ca2+ channel in the plasma membrane of pollen tube, and the effects of chemical messengers, such as spermidine and long-chain base phosphates, on pollen tube elongation has been uncovered. The overall publication in this project is more than 40 papers, and about 20 papers among them have been indexed by SCI, including the journals such as “Plant Cell”, "New Phytologist", "Plant Journal" and "Journal of Cell Science". Moreover, these results have been positively cited by the papers published in high impact journals such as "Science". The research results in this project is highly original and creative; it provides important leaps forward in our understanding of the interaction between pollen and pistil in pear.
4.Fruit Quality and Regulation Mechanisms
Basing on industry requirements, research on fruit quality and developmental biology, including sugar, acid, stone cells, aroma, shape and color, has been being conducted in our research team. Besides, some techniques on quality regulation were developed and put into cultural practice, which have benefited the social and economic efficiency.
This center has received 14 national and provincial awards, including the National Second-Class Award for Science and Technology Advancement, First-Class Award for Science and Technology Advancement and First-Class Award for Natural Science of the Ministry of Education, obtained 38 National invention patents. More than 10 books were published and more than 400 papers have been published, including the "Genome Research", "Plant Journal" etc.
This center has cultured more than 100 PhD students and Master students. One of the students win the "National Excellent Doctoral Dissertation Award" in 2012, and another student win the "National Excellent Doctoral Dissertation Award nomination" in 2013.
In the international cooperation, the center has been well collaborated with Mie University in Japan, Tohoku University in Japan, Ministry of Agriculture and Food of Canada, University of Birmingham in UK, University of Illinois in USA, University of California in USA, and carried out extensive and substantial research.
In social service, with fully understand of the main producing areas of the pear, we provide comprehensive substantial technology service in pear production around the China. Annual training growers and technical personnel more than 500 people.
Contact person for this project： Dr Peng Wang, Email: wangpeng@njau.edu.cn
