Effects of Heat Shock and 2,4-D Treatment on Morphological and Physiological Characteristics of Microspores and Microspore-Derived Doubled Haploid Plants in Brassica napus L

热激和2,4-D处理对甘蓝型油菜（Brassica napus L.）小孢子及其衍生的双单倍体植株形态和生理特性的影响