Effects of Near-surface Low Temperature on Freezing Injury of ‘Tunisian Soft-Seed’ Pomegranate

[Objective]The paper was to explore the influence of near-surface low temperature on cultivation of soft-seed pomegranate,and to provide guidance for planting location of soft-seed pomegranate.[Method]Taking 10 soft-seed pomegranate planting plots under different site conditions as the research objects,the near-surface low temperature of 45-50 cm was dynamically monitored from December 1,2018 to February 20,2019,and comparative analysis was made based on the local meteorological data over the same period.[Result]The near-surface low temperature of each temperature monitoring point was lower than the local meteorological data,which were all in the range of low temperature causing freezing in-jury of pomegranate trees,but the degree of freezing injury was different.The variation of near-surface low temperature was positively correlated with the altitude of terrain,but negatively correlated with the difference of topography and landform.When the local topography and landform were similar,the accumulation time of near-surface low temperature was negatively correlated with the altitude of terrain,while the duration of low tem-perature directly affected the degree of freezing injury.[Conclusion]The development of soft-seed pomegranate cultivation in Tunisia along Huang Mangling region in Henan Province refers to the local meteorological data.Meantime,it is also necessary to pay attention to the impact of regional microclimate environment,especially early monitoring of near-surface temperature to select suitable site and natural conditions.

Comparative proteomics analysis of pomegranate seeds on fruit maturation period(Punica granatum L.)

Seeds play a central role in the life cycle of plants. Seed hardness in pomegranates is of economic relevance, yet scarcely studied and poorly understood in China. In this study, we compared the proteomic differences between Zhongnonghong（soft-seeded） and Sanbai（hard-seeded） pomegranates. A total of 892 protein spots from both varieties were detected on two-dimensional electrophoresis gels（2-DE）; 76 spots showed greater than a 1.5-fold or less than a 0.66-fold difference（P〈0.05） in Zhongnonghong compared to Sanbai, of which 24 exhibited greater than a 2-fold change. Compared with Sanbai, Zhongnonghong possessed 14 up-regulated, and 10 down-regulated proteins. We identified and annotated 5 of these by using MALDI-TOF-TOF MS： pyruvate dehydrogenase（PDH） E1-β family protein（spot 4 609）; alanine aminotransferase 2-like（ALT2L）; mitochondrial glycine decarboxylase complex P-protein（spot 5 803）; phosphofructokinase B（Pfk B）-type family of carbohydrate kinase（spot 8 411）; and putative dna K-type molecular chaperone heat shock cognate protein 70（Hsc70）（spot 9 006）. Of these, 3 proteins（spots 4 609, 5 608, 5 803） were hypothesized to play a role in the formation of seed hardness. The other two proteins（spots 8 411, 9 006） were theorized to play a role in protecting the seeds from adverse stress during periods of fruit maturation. This study sets the foundation for further research on molecular mechanisms related to pomegranate seed hardness.