Study On Crossing Compatibility Of Different Peony Cultivars And Dormancy Breaking Of Peony Seeds

Paeonia lactiflora as a traditional famous flowers in China,has a high ornamental value and medicinal value.Cross breeding is an important method to cultivate new varieties of peony.And for a long time more through the natural hybrid and selecting of natural seedling of peony.Peony seeds under the natural conditions of slow germination,and low germination rate,seriously restricting the peony breeding and new varieties of cultivation.Therefore,it is important to study of directional hybridization in Sect.Paeonia and breaking dormancy in peony seeds,which is of great significance to the breeding and cultivating new varieties in peony.The study is through investigation of parent type,setting of cross combination and directional hybridization in Sect.Paeonia,to find cross combinations of high compatibility.Take the last year peony seeds and the current peony seeds as the test materials which are used to determine seed soaking rate,1000-seed weight,water content and viability,and break dormancy of hypocotyl and epicotyl to find an effective method of break dormancy of peony seeds.The results are as follows:1.A total of 17 peony cultivars were selected for directional hybridization in Sect.Paeonia through investigation.A total of 16 hybrid combinations were set up and the female parent was'Fen Yu Nu'.The 1569 flowers of pollination was collected a total of 5663 seeds and average seed-setting rate was 3.61 seeds of per flower.2.Male parent was important factor affecting seed-setting rate and rooting rate of peony seeds.There were seed setting for cross combinations which female parent was'Fen Yu Nu'.The seed-setting rate and rooting rate of cross combinationso of different male parent was different.The maximum seed-setting rate was 5.37 seeds of per flower and minimum seed-setting rate was 1.91 seeds of per flower.The maximum rooting rate was 54.00%and minimum rooting rate was 17.39%.3.According to seed-setting rate and rooting rate of cross combinations,selected some excellent hybrid combinations,including'Fen Yu Nu'×'Xi Shi Fen','Fen Yu Nu'×'Fen Mian Tao Hua','Ten Yu Nu'×'Yan Zi Xiang Yang','Fen Yu Nu'×'Shao Nu Zhaung','Fen Yu Nu'×'Lan Tian Piao Xiang' and'Fen Yu Nu'×'Hong Yu Qiu'.4.The water saturation time of last year and current peony seeds was 72 hour.The soaking rate of last year peony seeds was higher than current peony seeds.The 1000-seed weight of current peony seeds was 180.29g,water content of 43.31%,viability of 91.11%.And the 1000-seed weight of last year peony seeds was 182.29g,water content of 32.27%,viability of 72.22%.The seed quality of current peony seeds was better than the last year peony seeds and the current peony seeds were easy to germinate.5.GA3 could effectively break hypocotyl dormancy of peony seeds.IAA had a certain effect on the breaking hypocotyl dormancy of peony seeds,but the effect was not obvious.Treatment of peony seeds with 100mg/L GA3 was the best and rooting rate of 65.33%.Its first time of rooting was 12 days ahead of control check.6.The epicotyl dormancy of peony seeds could be effectively broken by low temperature or GA3+low temperature.The longer low temperature was,the better effect of breaking dormancy.Treatment of peony seeds with low temperature for 30 days and 300mg/L GA3 for soaking 4 hours was the best and germination rate of 76.67%.Its first seed germination time was 9 days.