[Preliminary study on the effect of climate factors on pollen fertility in Platycodon grandiflorum]

To have a better utilization of male sterile lines in heterozygotic breeding of Platycodon grandiflorum and provide theoretical basis for Platycodon grandiflorum hyboridization.

The pollen viability was detected by the means of aceto carmine dyeing, and the correlation analysis between climate factors of each anther development stage and pollen viability was estimated by Pearson coefficients.

Pollen viability variation range of male-sterile line GP1BC1-12 was 0% - 27%. That of male-sterile line GP12BC4-10 and chifeng germplasm was respectively 1.3% - 17.9% and 75.9% - 98.5%. Further linear regression analysis between climate factors of each anther development stage and pollen viability indicated that the degree of sensitivity varied with different germplasm of Platycodon grandiflorum. Among three germplasm, male sterile line GP12BC4-10 was the most stable one to the climate factors, and the male-sterile line GP1BC1-12 was the most sensitive one.

Temperature and solar irradiation are the most important climate factors to affect pollen viability in Platycodon grandflorum, and microspore mother cells stage (MMC) is its sensetive stage.