中国流行的马铃薯纺锤块茎类病毒（PSTVd）株系鉴定及其对产量的影响

从河北、内蒙古、山西、黑龙江、福建等省区采集虎头、克疫、紫花白、同薯８号、克新１号、克新４号和克新６号、燕子以及米拉等不同栽培品种感染ＰＳＴＶｄ的马铃薯样品中，制备ＰＳＴＶｄ粗提取物，以加拿大ＰＳＴＶｄ强毒株系（Ｓ－ＰＳＴＶｄ）和弱毒株系（Ｍ－ＰＳＴＶｄ）作对照，采用往返式聚丙烯酰胺凝胶电泳（Ｒ－ＰＡＧＥ）进行株系鉴定．结果表明，感染中国不同马铃薯品种ＰＳＴＶｄ的电泳迁移率均与加拿大Ｍ－ＰＳＴＶｄ的迁移率相同．初步表明侵染中国马铃薯的ＰＳＴＶｄ主要是Ｍ－ＰＳＴＶｄ．用ＰＳＴＶｄ虎头分离物，采用针刺块茎幼芽和叶片摩擦接种方法，分别接种到无ＰＳＴＶｄ的健康虎头和克皮上．检测结果表明，在初感染和续发感染植株中，ＰＳＴＶｄ浓度分布有共同的规律，从顶部叶片、中部叶片到基部叶片中ＰＳＴＶｄ浓度依次逐渐减少．ＰＳＴＶｄ接种明显抑制了植株生长，并造成较大的产量损失．由不同品种初感植株收获的块茎，均有很高的ＰＳＴＶｄ感染率．

Identification of Strains of PSTVd in China and Effect of PSTVd-infection on Potato Yield

Strains of PSTVd spread in China were identifed by "return" polyacrylamide gel electrophoresis (R-PAGE). PSTVd crude extracts from different potato cultivars: Tiger head,KeXin,Kuannae,Mira collected from Hebei,NeiMonggol,Shan Xi and Fujiang provinces were tested. Severe and mild strains of PSTVd from Canada were used as control. The results showed that electrophoretic mobility of all viroids tested were as the same as mild strain from Canada.The healthy "Tiger head" and Kuannae were inoculated with PSTVd from potato "Tiger head" by mechanical method in screenhous. Test showed that the growth of PSTVd-irifeted plants were markedly inhibited and potato yield decreased. The accumulation of PSTVd in PSTVd-inoculated potato plants were tested. The highest concentration was observed in the top leaves and the lowest was in the bottom leaves in the primarily and secondarily infected plants. Most of the tubers harvested from primarily infected plants were PSTVd infected.