甘薯病毒病复合体（SPVD）对甘薯产量形成的影晌

为探索SPVD对甘薯生长发育和产量形成的影响．本试验以高淀粉甘薯品种西成薯007的病毒苗、常规苗和脱毒苗为试验材料研究了SPVD在甘薯植株上的作用机理．得出以下结论：SPVD可导致甘薯地上部丛生和矮化、叶片变小而体现有效叶面积低，叶绿素含量降低，“源”变小，同化能力和光合能力降低：“流”变小，最终导致生物产量降低．而汰除SPVD可增大叶“源”和叶绿素含量．提高植株的光合能力和“流”的通畅性，从而增加产量。SPVD可使甘薯植株的SOD、POD和CAT活性降低，MDA含量上升．抗氧化活性降低．细胞膜受到伤害，最终导致产量降低，而脱除SPVD可增加SOD、POD和CAT在植株体内的活性，从而降低MDA对植株的危害。SPVD的脱除可增加3．4％的茎叶产量和2．9％的鲜薯产量，而SPVD浸染可使茎叶和鲜薯分别降低69．9％和49．1％。

Effect of SPVD on Sweet Potato Yield Formation

This study was to investigate the influence of SPVD on the growth devel- opment and yield formation of sweet potato, The virus seeding, landrace, virus-free seedlings of high starch sweet potato XichengO07 were inoculated with SPVD for revealing the interaction mechanism, The results showed that SPVD could result in clustering and dwarfing of sweet potato plant type, smaller leaves and lower effec- tive of leaf area, reduced chlorophyll content, and smaller source, lowered assimila- tive ability and photosynthetic capacity. The flow became smaller, further finally led to the reduced biological yield, and the desorption of SPVD could increase leaf ＂source＂ and the chlorophyll content, improve photosynthetic and flow ability, thus raising the output of production. SPVD could reduce the activities of SOD, POD and CAT in sweet potato plant, increase the content of MDA, decrease antioxidant activity and production, damage the cell membrane. However, virus-free treatment could increase the activities of SOD, POD and CAT in plants, which was helpful to reduce the harm of MDA. After the desorption of SPVD, the production of above- ground was increased by 3.4% and the production of fresh sweet potato was up by 2.9%, while SPVD dissemination could result in the reduction of the aboveground and fresh tubers by 69.9% and 49.1%, respectively.