| The pollination, the seed development, the best harvest time, the storage and germination conditions of the lustrum F. przewalskii in Ganlanzhou were studied during 2008-2009. The major results are as follows.1. Under microscope, the bulbs of F. przewalskii showed flowers morphogenesis before their aestivation. It could be determined that the pollination has been completed in early May through anther, ovary, style sliceing photos of F. przewalskii in different time.lt were the budding stage in this time in the field, indicating that the F. przewalskiii plants are self-pollinated plants. Further research on seed anatomy, it showed that the embryo development were later than that of the endosperm after pollination. Embryo continued to split after dormancy, revealing that the main reason for seeds dormancy were after-ripening of the embryos.2. The grain dry weight showed as'S'curve, which fitted to Logistic equation with a rapid increase during 41-66 d after blossom and finished at the end of 97 d. The grain filling rate showed'fast-slow-fast-slow' pattern. The seed bulk and protein culumation dyanamic all fitted to Logistic equation with stable seed bulk after 83 d and ceased protein cumulation after 118 d. The results show that the fast dehydrating rate and the stability of dry weight, bulk and protein content in seeds are the important indicates for seed maturation. The best harvest time should be during 77-82 d following blossom (at the end of July or beginning of August), during which the water content in the seeds should be lower than 40% and the seed capsules are not dissilient with still non-perishing stems.3. The pretreatment of F. przewalskii seeds were storaged with fixation in room temperature after (contrast), dry sand in room temperature, dry sand in low temperature and wet sand in low temperature for 4 months. Soluble protein, soluble sugar and starch contents were decreased significantly than the room temperature after fixation, the reduction sugar contents were increased significantly than the room temperature after fixation. Soluble protein contents were decreased in the course of storage, which were hydrolyzed by peptide hydrolase into amino acids for embryo growth. Storage substances of seeds were redistributed and reuse with wet sand in low temperature leading to increase length and thickness, reducation width. After ripening, the quality of the embryo accounted for 8.98%, which seeds germination rate was 80.7%.4. The 1000-grain weight ranged from 0.72 g to 0.82 g. The soaking process fitted to Logistic curve including sharp soaking, stable soaking and saturate soaking stages. The seeds can complete morphologic after-ripening after storaged for 45 d at 20℃and physiological afterripening after stratification mixed with sands (the ratio of sands to seeds is 4:1) for 150 d at 5-10℃. Under dark condition, the seed germination quality improved with temperature elevation and the optimum is 15℃resulting in 90.67% of germination rate and 89.33% of germination power. However, when over 15℃, the seed germination decreased significantly. The higher temperature also restrained the sprout growth. All above revealed that the temperature is the key condition for seed germination after afterripening. It suggests that it is the best time to sow F. przewalskii seeds when the soil temperature is 15℃under humid and adumbral condition.
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