Analysis on the methods of improving the Seedling quality of avocado

Avocado is a kind of exotic fruit with high nutritional value, which contains a variety of vitamins, fatty acids and proteins, and is known as "forest cream". However, because the taste of avocado is relatively light, in addition to seed conservation and breeding in our country, there is basically no commercial cultivation. With the improvement and change of consumption concept, the import consumption of avocado is increasing geometrically every year, which has led to domestic commercial planting. Today, the editor will talk about the methods to improve the quality of avocado seedlings.

1 introduction

Introduction refers to the selection and introduction of avocado seeds. Avocado seeds are mostly purchased from neighboring Vietnam or Myanmar, and the variety and quality of seeds are basically non-existent.

1.1 seed size

Seed size refers to the amount of nutrients that can be directly used during seed germination and seedling growth. seeds contain more nutrients, buds are strong, culms are thick, seedlings are good after planting, and they can be grafted earlier and come out of the nursery faster.

1.2 kinds of clothing stripping

The avocado seed is wrapped with a layer of waxy seed coat, which needs to be stripped, which is beneficial to the seed nucleus to absorb water and shorten the budding time. For those difficult to peel off, the pulp and sundries attached to the seed coat should be cleaned.

1.3 seed classification

Seeds should be distinguished according to size, good or bad. Size score: it is convenient for subsequent seedling bagging and separate management of strong and weak seedlings; good and bad points: separate germination of damaged and non-rotting seeds in the process of harvest and transportation to avoid possible disease infection.

2 budding

After the seeds harvested or purchased are treated, they will enter the budding stage, and the following points should be paid attention to:

A, budding bed: choose a flat and easy to drain land, to go to a place where there can be no low-lying stagnant water.

B, sprouting bed materials: choose clean coarse river sand, permeable and breathable, can be reused.

C, the specification of germination bed: the width of bud bed is 80 cm 100 cm, the thickness of sand layer of bud bed is not less than 20 cm, and the border of bud bed is separated by bricks. At the same time, drainage roads should be set aside to prevent rain and waterlogging.

D, if there is a general mud surface under the germination bed: first spread a layer of thick plastic film or hard waterproof board to prevent the seedling from penetrating the ground and reduce the root damage when the seedling is bagged; for hardened ground: sprout the bed directly above, pay attention to keep the walkway.

E, seed pre-germination management: the commonly used broad-spectrum germicidal solution was soaked for disinfection and sterilization time 5: 10 min.

F, seed planting row spacing: 15 cm × 10 cm row spacing, shallow trench buried in sand bed, covered with about 3 cm of sand, drenched through water.

3 seedlings on the bag

A, the tip of the seed bud can rise about 8 cm from the bed and move into the seedling bag to continue to breed. It is best to dip the root with the mud mixed with disinfectant and then bag it.

B, the choice of seedling bag cup: after filling the substrate, the height of the bag cup should not be less than 20 cm, the height should be more than 25 cm, and the diameter should be about 12 cm. Biodegradable nonwovens bag cup should be preferred.

C, choose water-preserving and breathable seedling substrate + a small amount of mountain soil + appropriate amount of organic fertilizer to avoid using pure soil alone.

D, the border width of fruit seedlings should not exceed 80 cm as far as possible after bagging, which is convenient for grafting operation in the future.

E, under the bag seedlings with bricks, pebbles or original bamboo strips and other things as cushion, not in direct contact with the ground to avoid waterlogging.

F, install automatic sprinkler facilities to improve spray quality and reduce workload.

G, set up a shelf and lay a sunshade net with a light transmittance of about 50%. After the seedlings adapt, they can be cultivated in the open air.

4 grafting

4.1 scion selection

Grafting can be carried out when the stem of the seedling is more than 0.6 cm (10 cm on the bag surface). The scion is superior to the outer sunny branch with full bud eyes and no fruit.

4.2 grafting method

The method of grafting is preferred, but at present, excellent mother trees are scarce, and the number of panicle strips is greatly restricted, so the feasibility of bud grafting can be discussed to improve the utilization rate of panicle buds and the number of grafted seedlings.

4.3 preparation before connection

Three days before grafting, the seedling stems were selected and placed separately according to whether they reached the grafting standard or not. After grafting, pour water once, pay attention to the rainy days can not be grafted.

5 Management after receiving

A, the grafting was completed and shaded for a period of time, and then the seedlings were uncovered after the scion germinated, and the watering was avoided as far as possible 3-5 days after the grafting, and then the seedlings should be watered in time to keep the substrate moist.

B, when the weather is fine, the sprouts and new buds under the marriage interface should be wiped off in time to ensure the nutrition supply of the scion.

C, timely fertilization is an important link in the cultivation of strong seedlings, which can be used alternately by root application and foliar fertilizer spraying.

D, when the scion sprouts grow to about 20 cm, each seedling is fixed with a small stick, and the main pole of the avocado seedling is tied against the pole to guide the seedling to grow upright and cultivate a good tree shape.

E, pay attention to observe the healing of the marriage interface, when the healing is complete or when the graft membrane is too tight, peel off the graft membrane in time.

6 other points for attention

A, avocado is vulnerable to root rot in fleshy roots, which should be paid attention to when necessary and various preventive measures such as sterilization should be strengthened.

B, when accelerating germination, the seed should be placed in the shape of a positive heart, with small head down and wide head up.

C, the harvest period of avocado seeds is longer and more scattered, and the seeds harvested or purchased should be treated and germinated in time.