巴西橡胶树野生种质与栽培品种橡胶粒径差异分析OA

Natural rubber is an important industrial raw material and strategic material,and rubber particle size is one of the key indicators affecting rubber quality and processing properties.To clarify the differences and regularity in rubber particle size characteristics between wild germplasms and cultivated varieties of Hevea brasiliensis preserved in the National Rubber Germplasm Repository,33 wild germplasms and 64 cultivated varieties were selected as research ma-terials in this study.Laser particle size analysis was adopted to determine particle size distribution parameters to inves-tigate the particle size discrepancies between the wild germplasms and the cultivated varieties.The average particle size of the cultivated varieties was significantly smaller than that of the wild germplasms.Among the wild germplasms,the maximum volume-average diameter reached 1.42 μm(accession XJ001337),and the maximum number-average diame-ter was 0.75 μm(accession XJ005636),which was 1.31 times and 2.27 times the corresponding maximum values of the cultivated varieties[1.08 μm(Hongxing 1)for volume-average diameter and 0.33 μm(Hongxing 1)for number-average diameter],respectively.Wild germplasm,XJ001337(volume-average diameter:1.42 μm;area-average diameter:1.25 μm;length-average diameter:1.01 μm),XJ001981(volume-average diameter:1.41 μm;area-average diameter:1.24 μm;length-average diameter:0.98 μm)and XJ005636(volume-average diameter:1.34 μm,area-average diameter:1.10 μm;length-average diameter:0.92 μm)exhibited conspicuously larger particle sizes in volume-average diameter,area-average diameter and length-average diameter,and could serve as ideal parental materials for modifying rubber particle size of cultivated varieties.Cultivated varieties Hongxing 1(volume mean diameter:1.08 μm)and AV385(volume mean diameter:1.07 μm)are materials with relatively large particle sizes among existing cultivated varieties,while Huoxing 72-5(volume mean diameter:0.55 μm)is the variety with the smallest particle size among all tested germplasms.These two can serve as core parents for the directional improvement of large and small particle size traits within cultivated varieties,respectively.The particle size variation pattern revealed in the study would provide theoret-ical basis and data support for the utilization of H.brasiliensis germplasm resources,rubber quality improvement and optimization of processing technologies.