Prevent the regeneration of degenerated leaves of garlic cloves

In a certain period of garlic growth, the scale buds begin to differentiate, the leaves degenerate, the scale buds gradually form cloves, and the scales outside the degraded buds form the outer skin of cloves, which is the general law of normal growth of garlic.

At the same time when the garlic stalk is exposed, a circle of small garlic leaves grows around the garlic stalk, and 5Mel 7 leaflets grow around the garlic stalk. These leaflets are a long new leaf growing from the outer skin of the new garlic cloves along the garlic stalk, but the growth point of the new garlic cloves does not sprout. This is called garlic degenerated leaf regrowth phenomenon, some called secondary growth phenomenon, also known as horsetail garlic. This phenomenon is the regrowth phenomenon of degenerated garlic leaves when it is stimulated by external conditions-atavism. It does not belong to "secondary differentiation", because it is a leaf growing from the outer skin of garlic cloves, while the new garlic cloves do not sprout. This kind of leaf emergence phenomenon has a great impact on the yield of garlic bolts, generally reducing the yield by 30%, 40%, and having little effect on the yield of garlic, generally reducing the yield by 10%.

The reason why it happened:

It has something to do with the sowing date. In the northern margin area, the leaf emergence rate was high before October 10, and lighter after October 10, and there was almost no leaf emergence phenomenon sowed at the end of October.

It is related to plastic film mulching. Practice has proved that the leaf emergence rate of plastic film mulching is high, and the leaf emergence rate of non-mulch is low or no leaf emergence. The leaf emergence rate of those sown and covered with plastic film before October 10 is about 98%.

It is related to the amount of nitrogen fertilizer applied. The leaf emergence rate of urea more than 50 kg / mu or nitrogen, phosphorus and potassium compound fertilizer more than 150 kg / mu was higher than that of base fertilizer, while the leaf emergence rate of lower nitrogen application rate of base fertilizer was lower.

It has something to do with variety. The leaf emergence rate of red garlic is high, the leaf emergence rate of white garlic is low, and there is basically no leaf emergence phenomenon of early bolting garlic (Ershui early) (only 23% of individual plots).

It has something to do with climate. Compared with 1996, the same red-skinned garlic was fertilized and sowed at the same time, and it was covered with plastic film at the same time. There was basically no leaf emergence in 1996, but it generally occurred in 1997. The autumn and winter of 1997 are warmer. The current impression is that warm winter is the main reason for the regrowth of degenerated leaves of garlic.

Preventive measures:

The phenomenon of regrowth of degenerated leaves of garlic is the result of the comprehensive action of many complex reasons. If the two factors do not exist, it is possible to avoid or reduce the occurrence of this phenomenon. Therefore, the following countermeasures should be taken in cultivation:

Control the sowing date. Open field cultivation in Shandong can be sowed in early October, and plastic film mulching cultivation can be sown in mid-October. In general, it can be broadcast late for 5 Mel for 7 days.

Formula fertilization, loose soil base fertilizer should be based on organic fertilizer, chemical fertilizer should be suitable, and nitrogen, phosphorus and potassium fertilizer should be matched in proportion. Before sowing, make the 50 cm deep soil loose and transparent, in order to promote the root system to develop to the deep layer and absorb the phosphorus and potassium nutrition of the deep soil.