Views:27 Author:Site Editor Publish Time: 2019-09-09 Origin:Site
Paeonia L. is a kind of beautiful ornamental plant. It is well-known both at home and abroad. Tree Peony and Paeonia lactiflora Pall have a long cultivation history in China. China is the origin and cultivation center of peony. Peony is the national flower of Tang, Ming and Qing dynasties. It has a cultivation history of more than 1600 years. Peony and Paeonia lactiflora Pall are called flower king and flower phase. So what is the reaction of flower king and flower crossing? Let's have a look.
Inter-Sectional Hybrid Breeds
The existing interspecific hybridization can be roughly divided into three types:
(1) herbaceous peony × tree peony
(2) tree peony × herbaceous peony
(3) tree peony or herbaceous peony × Paeonia lactiflora from North American
At present, Itoh hybrids on the market are all orthogonal offspring, such as Bartzella, Court Jester, Garden Treasure, Scarlet Heaven, Old Rose Dandy, Unique, First Arrival and Rose Fantasy. Inter-group backcross is very difficult because it is difficult to find parents with similar flowering period and suitable crossing, and backcross seeds are not easy to germinate, the normal germination rate is only about 1%.
The distant hybridization of F1 generation is usually sterile, but the intra-group hybridization of Paeonia lactiflora showed that the fertility of F1 generation was restored to a certain extent at the later stage of growth and maturity. Paeonia lactiflora belongs to distant hybrid F1 generation of normal fruit, but it does not produce seeds. In a few cases, it can produce a small amount of empty seeds, very few can form full seeds, while it can not germinate normally. Only a few seeds can grow into F2 generation plants. Intercrossing and backcross fertile between distant hybrid F2 plants in Paeonia lactiflora Pall group and Peony group. With the increase of hybridization algebra, the fertility of advanced generation hybrids in tree peony group was enhanced, and the compatibility with Paeonia lactiflora Pall was also enhanced. Therefore, the prospect of application in interspecific hybridization was generally promising. Therefore, by using the method of intra-group hybrids backcross and multi-generation selection, interspecific hybrids with strong fertility or affinity were bred, thus overcoming the technical difficulties of hybrid sterility.
Inter-group hybridization has the characteristics of both tree peony and P. lactiflora, and its ecological habits tend to be Paeonia lactiflora Pall. It belongs to perennial herbs. Its roots are similar to peony, its flesh is strong, dormant buds grow at the root neck, and its buds are usually pink. Its stems are similar to the stems of Paeonia lactiflora Pall, clustered and strong, with leaf buds growing on them and withering on the ground in winter. Its leaf shape is between peony and Paeonia lactiflora Pall. Leaf cleavage is similar to that of peony. Leaf leaves keep beautiful color during growth, do not appear spots, leaf margin wilting and other phenomena. They have strong disease resistance, low seed setting rate, mainly by ramet propagation and grafting propagation.
Inter-group hybridization mostly uses Paeonia lactiflora as female parent and Yellow Peony as male parent. Because of the color characteristics of yellow peony, most varieties are yellow. Famous varieties such as "Bartzella" and "Garden Treasure" are pure yellow, which make up for the lack of real yellow Germplasm in cultivated varieties. At the same time, because of the hybridization advantage, the interspecific hybridization population also appeared more abundant colors, including many novel colors, from white, pink, lavender, purple, red, purple-black and polychrome, which greatly expanded the chromatographic coverage of the flower color of Paeonia plants. At the same time, many varieties of petals with distinct spots at the base and stripes on the petals have become the ornamental point of interspecific hybridization.
In addition, many varieties show gradual changes from early blooming to blooming, such as "Juia Rose" blooming into bright red, with the opening of flowers gradually become orange, and finally yellow, at the same time, because of the different flowering stages of a single plant, sometimes there are three kinds of flower colors on the same plant, and the ornamental value is very high.