Improvement of petal pigmentation and flowering, and regulation of senescence in cut flowers through introducing fructan synthesis genes

(1)研究了弱光对洋桔梗花瓣色素形成的影响。遮荫的整个植物或茎和叶部分显着降低花瓣颜色的强度，而遮荫花没有影响it. When离体花与花序梗被放置在蔗糖溶液中，他们的花瓣颜色变得更加强烈，随着蔗糖浓度的增加，伴随着增加的查尔酮合成酶，查尔酮异构酶，和二氢黄酮醇4-还原酶的转录水平。这些结果表明，减少供应的光合产物是负责苍白的花瓣颜色在低光强度下。(2)在含有0.05 mg/l IBA、1 mg/l BA和0.1 mg/l GA 3的MS培养基上，叶段每培养产生8至18个芽。芽在含IAA的MS培养基上培养后，再置于含IBA的1/2 MS培养基上，40 ~ 50天生根。(3)利用pB 121和根癌农杆菌LBA 4404将大麦6-蔗糖：果聚糖果糖基转移酶（6-SFT）基因和枯草芽孢杆菌SacB基因导入洋桔梗植株中。将SacB基因与甘薯孢子素的液泡靶向序列融合。通过卡那霉素抗性和PCR分析筛选转化子。未获得6-SFT基因的转化体，而SacB基因的转化体经PCR检测，有32个转化体为卡那霉素抗性，15个转化体中100%含有SacB基因。(4)转化体的生根和随后的生长较差，并且它们没有达到开花期。在评价导入果聚糖合成基因对花色素的影响之前，需要对生根后的培养条件和驯化条件进行复查。

(1) We investigated the influence of low light intensity on petal pigmentation in lisianthus. Shading whole plants or the stem and leaf parts significantly reduced the intensity of petal color, whereas shading flowers had no effects on it. When detached flowers with peduncles were placed in sucrose solutions, their petal color became more intense as the sucrose concentration increased, concomitantly with increased levels of chalcone synthase, chalcone isomerase, and dihydroflavonol 4-reductase transcripts. These results suggest that reduced supply of photosynthates is responsible for pale petal color under low light intensity.(2) Leaf section produced 8 to 18 shoots per culture on MS media containing 0.05 mg/l IBA, 1 mg/l BA, and 0.1 mg/l GA3. These shoots were placed on 1/2 strength MS media containing IBA after they were incubated on MS media containing IAA.They rooted within 40 to 50 days.(3) We attempted to introduce 6-sucrose : fructan fructosyltransferase (6-SFT) gene from barley and SacB gene from Bacilus subtilis into lisianthus plants using pB121 and Agrobacterium tumefacience LBA4404. SacB gene was fused to vacuolar targeting sequence of sweet potato sporamin. The transformants were screened by kanamycin resistance and PCR analysis. We could not obtain any transformats for 6-SFT However, for SacB gene, 32 explants were kanamycin resistant and 100 % out of 15 kanamycin-resistant plants contained SacB gene according to PCR analysis.(4) The rooting and subsequent growth of the transformants were poor, and they did not reach the flowering stage. Reexamination of culture condition after rooting and acclimation condition will be needed before evaluating the effect of introducing fructan synthesis genes on flower pigmentaion.