蔗糖、硼、钙离子和γ-氨基丁酸对烟草花粉萌发的影响

摘要

采用液体培养法研究了蔗糖、硼酸、钙离子和γ-氨基丁酸(GABA)对4个烟草种(N.alata、N.tabacum L.cv.K326、N.repanda和N.stocktonii)花粉离体萌发的影响.结果表明:适宜浓度的蔗糖、硼酸、钙离子和GABA对花粉的萌发有较大的促进作用,超过最适浓度则起抑制作用.4个烟草种花粉离体培养的最适硼酸和钙离子浓度都为0.05 g/L,N.alata和N.tabacum L.cv.K326花粉萌发的最适蔗糖浓度为10％,N.repanda和N.stocktonii的最适蔗糖浓度为12％.N.alata和N.tabacum L.cv.K32花粉在10％蔗糖+0.05 g/L+H3 BO3+0.05 g/L Ca2+培养基上,花粉萌发率分别为92％和90％;N.repanda和N.stocktonii在12％蔗糖+0.05 g/L H3 BO3+0.05 g/L Ca2+培养基上,花粉萌发率分别为85％和87％.在上述有钙离子培养基中添加不同浓度的GABA,结果表明:N.taba-cum L.cv.K326、N.repanda和N.stocktonii在加入0.7～1 mmol/L GABA后花粉萌发率与不加入GABA时没有显著差异,GABA高于该浓度花粉萌发显著受抑制;而在培养基中加入0.7 mmol/L GABA后,N.alata花粉萌发受到抑制,花粉萌发率为81％.而在无钙离子培养基(10％蔗糖+0.05 g/L硼酸+1 mmol/L GABA)中培养N.alata花粉,花粉萌发率达到91％,表明适宜浓度的GABA具有促进花粉萌发的作用,而GABA和Ca2+在促进花粉萌发过程中可能具有协同作用.%The influences of sucrose, boric acid, calcium and GABA on the pollen germination of N. alata, N. tabacum L. cv. K326, N. repanda and N. stocktonii were studied with in vitro culture method. The result showed that the optimal concentration of su-crose, boric acid, calcium and GABA promoted pollen germination, while too high concentrations had disadvantage influence. For 4 Nicotiana species, the optimal boric acid and calcium ion concentrations were all 0. 05 g/L. The suitable sucrose gradiant for N. alata and N. tabacum L. cv. K326 is 10％, and 12％ for N. repanda and N. stocktonii. On 10％ sucrose+0. 05 g/L H3 BO3 +0. 05 g/L Ca2+medium, the pollen germination ratio was 92％ and 90％ for N. alata and N. tabacum L. cv. K326, respectively; the pollen germination ratios were 85％ and 87％ for N. repanda and N. stocktonii, respectively, on 12％ sucrose+0. 05 g/L H3 BO3 +0. 05 g/LCa2+medium. By adding 0. 7-1 mmol/L GABA into the above medium, the pollen germination rates of N. tabacum L. cv. K326, N. repanda and N. stocktonii differed insignificantly compared with the control, while it was restrained by adding GABA higher than 1 mmol/L. It was noteworthy that N. alata pollen germination was inhibited by adding GABA higher than 0. 7 mmol/L, and the pollen germination ratio dropped down to 81％. N. alata pollen was further cultured in 10％ sucrose+0. 05 g/L H3 BO3 +1 mmol/L GABA medium, and the pollen germination rate was up to 89％, which showed that optimal GABA could promote pollen germination, and GABA and Ca2+might have synergetic effects on promoting pollen germination.