Grafting propagation of the latest Shatian pomelo seedlings

Shatian pomelo belongs to the genus Citrus of Rutaceae. There are grafting method, barge branch (circle branch) method and cutting method in seedling cultivation, but in production practice, grafted seedlings are better than barge seedlings and cutting seedlings, so grapefruit seedlings are propagated by grafting method in production practice, and grapefruit seedlings are gradually eliminated by barging method and cutting method. Let's take a look at Shatian pomelo seedling grafting propagation.

Seed collection of rootstock

The rootstock of Shatian pomelo should choose sour pomelo tree (either red grapefruit or white grapefruit). The grapefruit has matured in Frosts Descent season. the seeds should be taken out after harvest and treated in time to prevent accumulation and mildew and affect germination. First wash the gum out of the seeds with ash water, then wash the makeup with clean water, then put it into the diluent of formalin and 50 parts of clear water (or one part of copper sulfate, 160 parts of clear water), soak for 10 minutes, take out and place for five minutes, then rinse with clean water, dry in a ventilated place, and sow seeds.

Selection of rootstock nursery

The nursery site should be selected in advance before the beginning of autumn, the nursery should choose south or southeast, good ventilation and light transmission, slope less than 10 degrees, thick soil layer (more than 20 cm), good water retention and drainage, convenient irrigation, sandy loam or sandy yellow loam with medium fertility, less wind damage, places free of diseases and insect pests, places with too heavy viscosity, thin spine, drought, poor drainage or high groundwater level (more than 1 meter). Are not suitable for nursery land.

Arrangement of rootstock nursery

Reasonable deep ploughing and fine soil preparation in rootstock nursery can promote the root growth of seedlings and improve the emergence rate per unit area and the quality of seedlings. Before sowing, the nursery should be deeply ploughed and dried to make the soil fully weathered, and drainage ditches should be opened around the nursery to facilitate drainage and irrigation. The nursery should be arranged in the east-west direction, generally 1.2 meters wide, 15 to 20 centimeters high, and 40 centimeters wide. The length of the border depends on the topography, the border surface should be flat, and the soil grains should be fine. A few days before sowing, apply grass fertilizer (about 1800 kg per mu of farm manure, 150kg of plant ash, and mix well with topsoil) before sowing.

Sowing in rootstock nursery

The treated seeds should be harvested in October, and then sown. When sowing, a horizontal trench should be opened on the border surface first, with a row spacing of 10 cm. The amount of seeds used per mu is about 15,018 kg, and about 60,000 seedlings can be produced. After sowing, cover with about 10 centimeters of fine soil, and then cover the border with fern grass, rice straw and other weeds, drench with water and moisturize it. In a place where irrigation is convenient, "horse race water" can also be irrigated once to soak the ground. Pay attention to dripping (irrigation) water during drought, often keep the nursery moist, promote seed germination, and uncover the covered grass after the seedlings are unearthed.

Management of rootstock nursery

After the rootstock seedlings are unearthed, the seedling bed should always be kept moist, but without stagnant water. When the seedlings grow two true leaves and the leaves turn dark green, they begin to fertilize. In the early stage, it should be applied frequently, once every ten days to half a month, six or seven times in a row, and in the later stage, appropriate fertilization should be applied according to the growth of seedlings, mainly nitrogen fertilizer such as human and animal feces and urine or ammonium sulfate, and appropriate application of phosphorus and potassium fertilizer such as plant ash or superphosphate.

Grafting of Shatian pomelo seedlings

In order to accelerate the propagation of seedlings to meet the needs of the development of Shatian pomelo production, small rootstock seedlings should be grafted as much as possible. the grafting methods include small bud grafting method, branch cutting method and "T" shaped bud grafting method. Small bud cutting method is more suitable for small rootstocks, which can be grafted earlier and come out of the nursery earlier. The small bud cutting method and T-shaped bud grafting method should be from late March to late June (the temperature is 15-20 degrees Celsius). The survival rate of grafted seedlings is the highest, the climatic conditions are not present in different areas, and the germination of buds on branches will be different sooner or later, depending on the changes of phenology.