Fund project: exploring the grafting technology of Michelia mollissima

Michelia mollissima belongs to Magnoliaceae Magnoliaceae. It blooms all the year round, flowering from March to June and fruiting from August to September. It has strong drought resistance and few diseases and insect pests. Next, the editor will talk about the application and demonstration of the 2012 central finance forestry science and technology promotion project "rare Garden Flower New Variety-Mo Zi Michelia in urban forest construction."

1 test materials and methods

1.1 Overview of the experimental site

Hunan Forest Botanical Garden, 50 ~ 106m above sea level, hilly landform, with an average annual temperature of 16.9 ℃, the highest temperature of 40.6 ℃, the lowest temperature of-9.5 ℃, an average annual precipitation of 1 400.6 mm, an average annual relative humidity of 80%, and an average annual sunshine hours of 1726 hours. The soil is an acidic red soil developed on the clay parent material of red soil in the fourth season, with pH values in the range of 4.05.5.

1.2 Test method

1.2.1 grafting experiment of rootstocks of different tree species

Magnolia mandshurica, Magnolia magnolia, Magnolia mandshurica, Michelia mollissima, Michelia mollissima and Magnolia mandshurica were used as rootstocks, and the robust seedlings were selected as rootstocks to investigate the survival rate of grafting.

1.2.2 experiments on different grafting methods

The survival rate of grafting and the growth of scion were investigated by cutting method in spring, peeling grafting method in summer and bud grafting method in autumn.

1.2.3 experiment on different grafting time

In late February, mid-March and late March, cutting was carried out by stages to investigate the survival rate of grafting, the growth of scion and the growth status of the whole grafted plant.

1.2.4 diameter class test of different grafted rootstocks

In late February, the sturdy branches of Michelia mollissima were selected and grafted with Magnolia magnolia of different ground diameter as rootstock, and the survival rate and growth of grafting were investigated.

The diameter grades of rootstocks were as follows: < 0.5 cm, 0.6 ~ 1.0 cm, 1.1 ~ 1.5 cm, 1.6 ~ 2.0 cm, 2.1 ~ 3.0 cm.

1.2.5 experiment on different times of sprouting after grafting

After seedling grafting, because the main buds, lateral buds and hidden buds on the rootstock can continue to germinate and grow, it is not enough to wipe buds once.

In this study, different times of sprouting were set: 0, 4, 6, 10 times, and the survival rate of grafted seedlings and scion growth were investigated.

1.2.6 experiment on different unbinding time after grafting

When the scion grafted the rootstock, the plastic strip (belt) was used to fix it on the rootstock, but the growth of the scion and rootstock would be affected after a certain period of time. Therefore, this study set different unbinding time: unbinding, 40 days after grafting, 60 days after grafting, to investigate the survival rate and growth of grafted seedlings.

1.3 data Statistics and Analysis

Excel2007 software was used to preprocess the data and SPSS 17.0 statistical software was used to analyze the data.

2 results and analysis

2.1 effects of rootstocks of different tree species on survival rate of grafting

In the experiment, 6 tree species of 3 genera of Magnoliaceae were used as rootstocks and grafted by cutting method. The survival rate of grafting was investigated. The results are shown in Table 1.

Table 1 effects of different rootstocks on survival rate and growth of grafting

It can be seen from Table 1 that there are significant differences in grafting survival rates between rootstocks of different tree species and Michelia mollissima scion. The grafting survival rates of Michelia mollissima and Michelia mollissima rootstocks are lower, which are only 42.5% and 40.0%, respectively. Magnolia mandshurica is the lowest, only 16.7%.

2.2 effects of different grafting methods on survival rate and growth of grafting

Table 2 effects of different grafting methods on survival rate and growth of grafting

It can be seen from Table 2 that among the three grafting methods, the survival rate and scion height growth of cutting method are the highest, the survival rate of young shoot peeling grafting method is the lowest, the operation of cutting method is simple, the working efficiency is high, and it is not necessary to wait for rootstock peeling before grafting, so the grafting period can be earlier and the grafting time can be prolonged.

2.3 effect of different grafting time on the survival rate of grafting.

When cutting in spring, choosing the right time is very important for the survival rate of grafting. The survey results are shown in Table 3.

Table 3 effect of different grafting time on survival rate of grafting

It can be seen from Table 3 that the suitable grafting time of Michelia mollissima is in the middle of 2-3. During this period, the survival rate of grafting is higher, and the growth of grafted seedlings is better, but from late March, the survival rate of grafting decreases sharply, and the growth of scion also decreases.

2.4 effect of rootstock diameter class on scion growth

Table 4 effect of diameter class of grafted rootstock on scion growth

Table 4 shows that the survival rate of grafting is the lowest when the ground diameter of rootstock is less than 0.5 cm, and the survival rate of grafting is the highest when the diameter of rootstock is more than 2 cm, that is, the survival rate of grafting increases with the increase of rootstock thickness.

The SPSS software was used to analyze the growth of scion height after grafting survival of rootstocks with different thickness. the results showed that when the ground diameter of rootstocks was more than 0.6 cm, the effect of rootstock thickness on scion height growth was not significant.

2.5 effect of sprouting times on seedling growth after grafting

Table 5 effect of sprouting times on the growth of grafted seedlings

It can be seen from Table 5 that different times of sprouting have a significant effect on the survival rate of grafted seedlings. With the increase of sprouting times, the survival rate of grafted seedlings increased and the growth of scion was better.

2.6 effect of bundled strips on seedling growth after grafting

Table 6 effect of binding strips on the growth of grafted seedlings

It can be seen from Table 6 that removing the binding strip 40 days after grafting is most beneficial to the survival and growth of grafted seedlings, and the survival rate of grafted seedlings is 95.23%.

3 conclusion and discussion

When selecting rootstocks of Michelia mollissima, the grafting survival rate of Magnolia magnolia as rootstock is the highest, while the grafting survival rate of Michelia mollissima and Michelia mollissima of the same family is not high, so it can be selected as the grafting rootstock of Michelia mollissima in production practice.

Different grafting methods have a significant effect on the survival rate of Michelia mollissima grafting, and the cutting method has the best effect.

Different grafting time has a significant effect on the grafting survival rate of Michelia mollissima. The best grafting time is from late February to mid March. Later than this period, the grafting survival rate decreases significantly.

The survival management of Michelia mollissima after grafting is also an important factor affecting the growth of grafted seedlings, and the survival rate of grafted seedlings increases with the increase of sprouting times.

Grafting culture technique of Michelia mollissima

The grafting culture of Michelia mollissima has the advantages of fast growth, early flowering, high survival rate, simple operation, no time limit and so on.

I. selection of rootstock species

Magnolia, Magnolia and Magnolia can be used as rootstocks for grafting Michelia mollissima. Among them, the fibrous root of Magnolia is well developed, which is the most suitable for pot planting, and the other lateral roots are stout and suitable for planting.

2. Selection of scion

As the old tree blossoms early, you can try to use the old smile as the mother tree. According to the ear, the outer middle and upper skin of the crown is green, the axillary buds are full and there are no diseases and insect pests. One-year-old to annual branches. If the ear source is sufficient, the tip should be used as the scion. The ear is about 6 cm long, leaving only 1 ~ 2 leaves at the top.

III. Original time

Outside, it can be grafted from the end of February to the end of September, depending on the rootstock. General sowing and breeding rootstock seedlings can be grafted as long as the tax exceeds the scion. The tiller strips transplanted with roots can be grafted after survival because they have a certain thickness.

4. Grafting method

Glue it together. First clean the rootstock to connect one side, use a sharp blade to cut at about 7 cm on the soil, and the cutting surface is 3 cm ~ 4 cm long. Only to the xylem (the water yellow is the best for the formation layer). Cut out a 30-degree slope at the end of the ear, and then cut the slope just above the cambium to a surface as long as the rootstock. Align the anvil and spike into a layer, and wrap the whole cutting surface with plastic film belt from top to bottom. Grafting in summer and autumn uses a piece of plastic film to bind the interface, and then use paper as a shade.

V. Post-management

Anvil buds should be removed frequently before and after survival. Be careful not to accumulate water at the root of the rootstock, otherwise the root will rot easily and the whole plant will die. One month after grafting, the interface healed, the sunshade and cover film were removed, and the upper part was cut off from the 3 ~ 5 leaves of the dead wood to promote panicle bud germination. When the scion tip is 5 cm ~ 7 cm long, cut off the above rootstocks at the interface and relax and wrap the plastic tape.

Grafting method of Michelia mollissima

The shape of Michelia mollissima is very similar to that of Michelia mollissima, but the color and size are still different from Michelia mollissima. Because Michelia mollissima has a certain aroma, it is also a kind of aromatic ornamental tree plant. The propagation of Michelia mollissima is generally carried out through the method of grafting, so what problems should be paid attention to when grafting?

Michelia mollissima

I. selection of rootstocks

Magnoliaceae plants such as Michelia mollissima, Michelia mollissima, Magnoliaceae, Magnolia and Magnolia can be used as rootstocks for grafting Michelia mollissima. Among them, Michelia mollissima has well-developed main roots, which is an ideal rootstock for grafting Michelia mollissima. In production practice, one-year-old Michelia mollissima seedlings were cultivated as rootstocks of Michelia mollissima.

2. Selection of scion

The 1-2-year-old flowering branches with strong growth were selected as scions, and the annual branches with green skin, full axillary buds and no diseases and insect pests were the best. The ear is about 2 cm long, leaving a bud.

III. Grafting season

In the south of Jiangxi, it can be grafted from the end of February to the end of March. Generally, rootstocks that are sown and propagated can be grafted as long as they exceed the scion.

4. Grafting method

1. Rootstock treatment

The rootstock was cut off or sawed 10 cm above the ground, and the cut was cut into a smooth surface to facilitate healing. The specific height should consider factors such as the thickness of the scion and the sprouting of the rootstock. The scion is thin, the rootstock is also thin, and the cut is high from the ground. In order to reduce the sprouting of rootstocks, the cut should be low. Then gently split vertically from the cutting section of the rootstock with a grafting knife, the length of the split is about 2ml 3cm, and the width of the split should be equal to that of the scion.

2. Scion treatment

The length of the scion is the length between two buds, and the thickness of the scion is the same as that of the rootstock. The scion is cut with a sharp blade about 1 cm from the bud above the scion, and then cut off about 1 cm from the next bud. Then from about 1 cm from the bud, the cutting surface is 2 cm-3 cm long, only as deep as the xylem. Then cut the reverse side of the scion into a 30-degree slope, which is about 1/3 of the length of the cutting surface.

3. Grafting method

Using split grafting, insert the treated scion into the split of the rootstock, expose 0.l-0.2 cm, ensure the normal growth of buds on the scion, align the scion with the cambium of the rootstock, if the size of the scion and the rootstock are not the same, it is difficult to align both sides of the cambium at the same time, there must be cambium alignment on one side. The split length of the rootstock should be consistent with the cut length of the scion, and immediately after joining, the split length of the rootstock should be fastened with plastic tape so as not to stagger between the scion and the rootstock cambium.

V. Post-management

Anvil buds should be removed frequently before and after survival. Be careful not to accumulate water at the root of the rootstock, otherwise the root will rot easily and even die. After the grafting survived, the sunshade and grafting film were removed.