水杨酸对鸭梨和雪花梨花粉萌发及花粉管生长的影响

适宜浓度的外源水杨酸(SA)可以促进鸭梨(Pyrus bretschneideri Rehd.cv.Yali)和雪花梨(P.breschneideri Redh.cv.Xuehuali)花粉的萌发和花粉管的生长.采用质膜Ca2+通道抑制剂LaCl3、胞外Ca2+螯合剂乙二醇-双-(2-氨基乙醚)四乙酸(EGTA)及CaCl2分别与不同浓度SA组成培养基对鸭梨和雪花梨的花粉进行培养,结果表明,0.000 2、0.002 0、0.0200 mmol/L的SA均可拮抗EGTA对花粉萌发及花粉管生长的抑制作用,花粉发芽率比对照高,花粉管生长速度快,LaCl3与SA培养花粉有同样的效果.CaCl2与SA共同培养一定程度上可削弱SA对花粉的促进作用,但0.0020 mmol/L SA处理,花粉的发芽率和花粉管的生长速度高于对照.说明Ca2+参与了SA对花粉萌发及花粉管生长调节作用的信号转导过程,SA通过提高花粉内Ca2+],的浓度促进花粉萌发及花粉管生长,胞内钙库可能是Ca2+的主要来源.

Effect of Salicylic Acid on Pollen Germinating and Pollen Tube Growth of Pear

The treatments of 0.000 2、0.002 0、0.020 0 mmol/L salicylic acid(SA) accelerated germination of pollen and tube growth in pear.Pollen of Yali and Xuehuali was cultured in medium containing SA with EGTA,LaCl3 and CaCl2 separately.The results showed that 0.000 2,0.002 0,0.020 0 mmol/L SA treatments antagonized the inhibition of EGTA on germination of pollen and extending of pollen tube,and the same to LaCl3.But the accelerating action of SA on pollen growth was counteracted by using CaCl2;the gemination rate and pollen tube length of pear treated by 0.000 2 mmol/L SA was obviously higher than that of control.Those results suggested that Ca2+ is involved in the signal transduction during pollen germination in pear induced by SA.Cytosolic free calcium(i) was increased by SA,there by accelerate germination of pollen and extend pollen tube,mainly from the intracellular storage and partly from the extracellular space.