A Study On The Distant Hybridization And Germplasm Innovation Of Lilium Lancifolium Thunb And Three Ornamental Lilies

In order to explore the method of overcoming the fertilization barrier of distant hybridization of Lilium lancifolium Thunb,obtain hybrid seedlings,and study the best propagation method of hybrid seedlings.In this experiment,L.lancifolium Thunb was used as the female parent and three ornamental lily Varieties ’darksecret’ ’tresor ’ and’ Sorbonne’ as the male parent.The orthogonal experimental design was used to screen the best formula of pollen germination solution,detect the pollen germination rate of different male parents,overcome the pre fertilization obstacles of distant hybridization between L.lancifolium Thunb and three ornamental lilies through four different pollination methods,and rescue the embryos of the obtained hybrid offspring to overcome the post fertilization obstacles.After the hybrid seedlings were successfully obtained,the best methods of hybrid seedling proliferation and expansion rooting were studied to obtain a large number of hybrid seedling offspring.Finally,the appropriate SSR molecular marker primers of lily were selected for early identification of hybrid seedlings.The results are as follows:(1)The best germination solution formula with the highest germination rate of the three male parents is 150 g/L sucrose+100 mg/L boric acid+125 mg/L calcium chloride.Among the three male parent pollen,’Sorbonne’ has a slightly higher germination rate as a whole,and the average germination rate in the best germination solution is 58.16%,‘Dark secret’has a mean germination rate of 48.61%,’tresor’ has a low germination rate,and the average germination rate in the best germination solution is only 26.11%.(2)Four pollination methods were used for cross pollination,among which the pollination method with the highest seed setting rate was bud pollination,and the seed setting rate was 14.44%.A total of 25 capsules were obtained from the three hybrid combinations,and the hybrid combination with the largest number of capsules was L.lancifolium Thunb×’Dark secret’,the seed setting rate was 14.17%.Therefore,the best way to overcome the pre fertilization obstacle of L.lancifolium Thunb ’s distant hybridization is bud pollination.(3)Through ovule culture,the post fertilization obstacles of hybrid offspring were overcome,and 9 F1 hybrid seedlings were successfully obtained,including 1 hybrid seedling of L.lancifolium Thunb×’Dark secret’,and 8 hybrid seedlings of L.lancifolium Thunb×’Tresor’.The formula of ovule culture medium is MS+30 g/L sucrose+0.01 mg/l NAA+6.5 g/l agar,pH value is 5.7.(4)The most suitable medium formula for the proliferation and propagation of hybrid seedlings was MS+30 g/L sucrose+0.1 mg/l NAA+1 mg/L 6-BA+8 g/L agar,pH value is 5.8;and the best medium formula for bulb expansion and rooting was MS+80 g/L sucrose+0.1 mg/l NAA+0.05 mg/1 6-BA+0.75 g/l activated carbon+6.5 g/l agar,pH value is 5.8;The best cultivation environment is dark cultivation(5)SSR molecular marker identification was carried out on the obtained two hybrid lines of L.lancifolium Thunb×’Tresor’,and 4 pairs of primers were finally screened from 23 pairs of primers,which confirmed that the two lines were true hybrids.In this paper,a set of methods suitable for overcoming the barriers of distant hybridization of L.lancifolium Thunb and a culture system for tissue culture and rapid propagation of hybrid progeny were established,and provided theoretical support and material basis for further cultivating new varieties of lily for both appreciation and food in the future.