美洲狼尾草柱头可授性和象草花粉活力的研究  

Pollen Viability of Pennisetum purpureum and Stigma Receptivity of P.americamum

作　　者：穆少杰[1,2] 钟小仙[2] 顾洪如[2] 沈益新[1] 

机构地区：[1]南京农业大学动物科技学院,江苏南京210095 [2]江苏省农业科学院畜牧研究所,江苏南京210014

出　　处：《中国草地学报》2010年第2期37-41,共5页Chinese Journal of Grassland

基　　金：国家科技支撑计划项目(2006BAD16B02-4);江苏省青年科技创新人才项目(BK2007516);浙江省科技计划项目(2007C22060)

摘　　要：以杂交狼尾草母本美洲狼尾草不育系Tift 23A和父本象草N51为材料,采用花粉离体萌发法测定花粉活力,用联苯胺-过氧化氢法测定柱头可授性,结合柱头形态特征观测与田间人工杂交授粉试验进行研究。结果表明:象草抽穗1d后开始散粉,散粉期持续7d;散粉第1d花粉活力较高,为71.6%,第2～4d花粉量最多,花粉活力显著高于其它各天,平均值达77.2%,之后迅速下降,第7d时散粉量极少,花粉活力降到50.3%。美洲狼尾草柱头可授期为7d,可授性为2～3d柱头>1d、4d柱头>5～7d柱头;柱头抽出第1～4d人工授粉杂交结实率极显著高于5～7d,其中2～3d的田间人工授粉平均结实率显著高于其它各天,为84.1%;柱头呈白色,开裂角度为60°～90°时具有最强可授性。Sterile line Tift 23A of Pennisetum americamum as maternal and P.purpureum N51 as paternal,the pollen viability of P.purpureum was evaluated by pollen germination test in vitro.The stigma receptivity of P.americamum was estimated with benzidine-H2O2 method.The results of observation of stigma morphological characteristics and artificial hybridization in the field showed that the pollen of P.purpureum began to shed on first day after spike outstretching the flag leaf wholly and the scattering stage lasted about 7 days.The viability of pollen scattered on the first day was 71.6%,relatively higher.The scattered pollen amount was the largest from the second day to fourth day and the pollen viability reached 77.2% on average which was significant higher,then decreased quickly.The pollen viability was 50.3% on the seventh day,meanwhile the pollen grains were few.The stigma receptive stage of Pennisetum americamum lasted 7 days.The sequence of stigma receptivity was as follows：2～3d1d,4d5～7d.The seed-setting rate of artificial pollination was extremely significant higher in 1～4 days after stigma outstretching the spike than in 5～7 days.The average seed-setting rate of artificial pollination in 2～3 days after stigma outstretching the spike was 84.1%,significant higher than other days.The stigma had highest receptivity when its color was white and its split angle was 60°～90°.

关 键 词：美洲狼尾草 象草 花粉活力 柱头可授性 结实率 

分 类 号：Q945.6[生物学—植物学]