The Effect Of Ca²⁺ And Ca²⁺ Inhibitors On Magnolia Soulangeana Soul.-Bod. Pollen Germination

To take the pollen of Magnolia soulangeana Soul.-Bod. as a plant material, we have carried out researches about the effect of Ca²⁺ and Ca²⁺ inhibitors on pollen germination,the distribution of free cytoplasm Ca²⁺ on pollen germination and the effect of cryopreservation on pollen viability.1. The best pollen germination conditionBoron acid obviously affected pollen germination, the best boron acid concentration was 1mmol/L, which got 90.50 % pollen germination rate and 229.2μm pollen tube length. The promotive effect of Ca²⁺ on pollen tube length was better than on pollen germination rate, and the best Ca²⁺ concentration was 0.01mmol/L for pollen germination rate and was 1mmol/L for pollen tube length. In a word, 0.1mmol/L Ca²⁺ would be the best concentration, which got 40.69% pollen germination rate and 93.53μm pollen tube length. The best La³⁺ concentration for pollen germination was 20μmol/L, which has 47.13% pollen germination rate and 111.60μm pollen tube length. Pollen germination was restrained when La³⁺ concentration rised. After 0.1mmol/L Ca²⁺ was added to the culture medium the pollen germination got into ambiguity, the pollen tube growth was restrained. It was demonstrated that Ca²⁺ mitigated the function of La³⁺. In any cases, Al³⁺ restrained the pollen germination and pollen tube growth. Ca²⁺ also mitigated the function of Al³⁺ a little.2. The distribution of free cytoplasm Ca²⁺ during pollen germinationThe results of free cytoplasm Ca²⁺ distribution observation showed that the Magnolia soulangeana pollen had stockpiled abundant Ca²⁺ which aroused much free cytoplasm Ca²⁺ fluoresece without additional Ca²⁺ and sufficed pollen germinate and pollen tube's early growth. There was ruleless effect of boron acid concentration changing on pollen free cytoplasm Ca²⁺ fluorescence, but boron acid lead the hyperpolarization-activated Ca²⁺ across the cytoplasm. Free cytoplasm Ca²⁺ fluorescence changed along with Ca²⁺ concentration changing. Trivalent cations La³⁺ and Al³⁺ strongly elevated free cytoplasm Ca²⁺ fluorescence. Interactional effects between La³⁺ and Ca²⁺ were much stronger than between Al³⁺ and Ca²⁺. Free cytoplasm Ca²⁺ fluorescence was markedly declined on 20 and 40μmol/L La³⁺ concentration, whereas there was little declined on the low Al³⁺ concentration.3. The pollen cryopreservation and the pollen viability determinationGoing with the stretching of cryopreservation time, pollen germination rate was declined slowly. It was better for pollen preserve with lower water content. 2h's torrefaction endued pollen with better vigor than 4h's torrefaction.