Zinnia breeding and cultivation

Zinnia, also known as backgammon, Yemei, Wumeimei, is an annual herbal flower of Zinnia. Plant height 40-120 cm, stem upright, short hairs, rough surface. Leaves opposite, oval or oval, leaf base amplexicaul. Head size 5-15 cm in diameter, born on the top of branches, with long pedicels. There are many round ray flowers, the petals are obovate, the tip tip is rolled backwards, and there are white, yellow, red, pink, purple, green, orange, etc. The cylindrical flowers are concentrated in the center of the disk. The inflorescences are in multiple bell-shaped and base joints. The ray flowers can also be strong. The achenes are ovate or bottle-shaped. The apex is acuminate and the middle is slightly concave. The achenes produced in tubular flowers are oval in shape and small in size. From August to October, the fruit of zinnia matured and its seed life lasted for 3 years. The zinnia flowering period is from June to October. Zinnia long-term artificial hybridization and breeding, cultivars are more numerous, can be divided into large flower tall stem type, flower stem type and small flower cluster type. The tall stem-shaped plant height is 90-120 cm, with few branches, and the diameter of the terminal inflorescence can reach 12-15 cm. Middle flower stem type 50-60 cm tall, more branches, inflorescence diameter of 6-8 cm, the top slightly flat, the entire inflorescence approximately flat spherical. The flower-growing type plant height is 40 cm, and the branches are numerous. The number of flowers per plant is also large, but the inflorescence diameter is small, only 3 to 5 cm. The tongue-like flowers spread flat without rolling, and the inflorescence looks like a sphere. The new type of dwarf line Zinnia developed in the 1970s was flat, semicircular, with a flower diameter of 7-8 cm and a plant height of 30 cm or less. The shortest mini plant height is only 20 cm and the flower diameter is about 4 cm. The Hundred Day Grassland produces Mexico and other places and is now widely cultivated around the world. Its strong nature, adaptability, deep roots, stalks hard and easy lodging. Hi Sunny, hi warm, not cold, resistant to poor, drought-resistant, avoid continuous work, afraid of hot and humid. The land that grows in fertile and deep soil layers grows well, and when it is potted, sandy soil that contains humus, loose and fertile, and has good drainage is preferred. Zinnia is propagated, usually by sowing. The suitable temperature for germination is from 20°C to 25°C and it can germinate within 7-10 days. The sowing time in the open field should not be too early. If the temperature drops below 15°C after emergence, the seedlings will stop growing and will always grow poorly to form a “little old seedling”. When the seedling height is 5-8 centimeters, it should be planted once. In late May, it can be transplanted and planted in flower beds. After mid-June, it is also desirable to take side branch cuttings for breeding. Pay attention to shade and rain, so as to avoid cutting infection and rot. Potted Zinnia should be selected as a new type of dwarf line and a dwarf big flower variety, which can be sown in the greenhouse in early February. In mid-March, the seedlings are transferred into a pot with an inner diameter of 10 cm, one for each pot, and changed in early April. Into the inner diameter in 18 cm pot colonization. Under the conditions of stable room temperature, adequate light, air circulation, and appropriate water and fertilizer, Zinnia can be exhibited on the “May Day” festival.