Anther Culture And Evaluation Of Regenerated Plants In Potato

Anthers from thirty-eight genotypes of potato were cultured in vitro. The effects of genotypeand types of medium on callus formation and differentiation in anther culture were analyzed.Factors that influence callus induction and anther browning rate, such as developmental stage ofpollen, pretreatment, the hormones and hormone concentrations, sucrose concentration, AgNO₃concentration, active carbon and vitamine C during the culture process, were investigated using sixgenotypes of Ne16, Kexin13, Kexin17, Kexin18, Hua525 and Bo C. Ploidy level of the regeneratedplants were determined by chromosome counting and the chloroplast number in stomatal guard cell.The agronomic traits of dihaploid plant regenerated from anther culture were also studied.The results are as follows:1. The size of flower bud and size and color of anther could be used as simple but reliableindex for judgment of the developmental stage of microspores. When flower bud is 6.0-8.5 mmlong, and anther is 3.0-5.0 mm long and light green, microspore is in mononucleated stage.2. Under the same cultural conditions, different genotype had different ability for callusformation. Ne 16 ranked in the first place for callus formation. Totally, 960 anthers were cultured,and 43 calluses were produced, the induction rate being 4.3ï¼…. Bo C ranked second, with inductionrate being 3.5ï¼….3. Pretreatment of low temperature could increase the rate of callus formation, but too tong ortoo short pretreatment was unfavorable for callus formation. 4℃for 2d was considered helpful.High temperature was also effective. Pretreatment of anther after inoculation at 33℃for 2 d wasfavorable for callus formation.4. The anthers from Ne 16 and Bo C were pretreated with mannitol. The rate of callusformation increased first with advance in days after treatment, and then decreased. It was 4 d aftertreatment when the rate of callus formation was maximal.5. Hormone played an important role in potato anther culture. MS+NAA 0.5mg/L+2, 4-D 0.5mg/L+KT 0.5 mg/L was more suitable for callus formation.6. The medium with 6ï¼…sucrose gave the highest callus induction rate. Potato extracts couldincrease callus induction and the suitable concentration was 50 g/L.7. Medium added with 20 mg/L AgNO₃ could reduce the anther browning rate effectively andincrease callus induction rate. The browning rate of anthers decreased as increase in vitamine C concentration.8. When active carbon was added to medium, the anther browning rate was decreased, butcallus induction rate was not improved. The callus formation was inhibited when active carbon wasincreased up to 3g/L.9. Relationship between the number of chloroplast in stomatal guard cell and the ploidy levelwas noted. The chloroplast number of dihaploid was between 10-18, and the chloroplast number oftetraploid cultivars was between 20-30.10. Differences in the dihaploids and their parental tetraploid cultivars were noted in the traitssuch as plant vigor, leaf color and tuber shape.