Effects of ring cutting and ring peeling on yield and quality of young Ziziphus jujuba

Effects of ring cutting and ring peeling on yield and quality of young Ziziphus jujuba

Ring cutting and ring peeling of jujube branches are commonly used measures to improve fruit setting rate. Girdling and circumferential cutting can retard the transport of photosynthate down the tree, affect the growth and absorption of roots, control vegetative growth, promote flower formation and fruit setting, and improve yield and fruit quality. Due to the poor understanding and technical implementation of ring cutting and peeling of jujube trees by jujube farmers, the fruit setting rate is low, which affects the yield and benefit. The author carried out ring cutting and ring peeling experiments on young trees of Ziziphus jujuba in 2016 to provide a theoretical basis for selecting appropriate and effective technology for production.

1 general situation of the experimental site

The experimental site is located in a 100,000 mu ecological garden in Wensu County, Aksu Prefecture, Xinjiang, with sandy loam and low groundwater level. Direct seeding sour jujube garden was established in 2010, covering an area of 2hm2 (30 mu), with a row spacing of 0.75m × 2m and 444 plants per 666.7m2. Grafted grey jujube in 2011, the plant was as high as 1.7m in that year, and the main variety was grey jujube. The use of water-saving irrigation, small crown sparse layer tree. In 2016, trunk diameter 6.3cm, trunk ring cutting and ring peeling experiments were carried out (figure 1, figure 2).

Fig. 1 girdling method of grey jujube trunk

2 experimental design and method

The plants with uniform growth and uniform size were selected for the experiment, and the ring cutting and ring peeling were carried out at the height of the trunk 30cm. Five treatments were set up in the experiment: one ① ring cutting was carried out in the middle of June. Two ② rings were cut, and the second ring was cut at the upper 5cm of the first ring every 7 to 10 days after it was cut in full bloom in the middle of June. Three ③ rings were cut. After the first and second rings were cut, the third ring was cut at the upper 5cm of the second ring every 7 to 10 days. To deal with ④ girdling, one girdle was peeled in full bloom in the middle of June, and the width of peeling mouth was about 0.5cm [1]. Treatment of ⑤ control, no ring cutting, no ring peeling. 10 trees were treated each.

Ring peeling, ring cutting straight and complete, no stubble (figure 1, figure 2). Within 8 hours after treatment, Guofukang was used to promote wound healing and prevent the occurrence of diseases and insect pests. Strengthen the management of water and fertilizer to ensure the nutrient supply of trees.

Fig. 2 main trunk ring cutting method of Ziziphus jujuba

According to the investigation, a side branch listing mark with a southward direction and a diameter of about 2cm was selected at the height of 1 m of each young jujube tree. The hanging number, inflorescence number and inflorescence fruit number of jujube were investigated on July 5, and the fruit setting number, single fruit weight, commercial fruit number, abnormal fruit number, split fruit number, fruit edible rate and so on were investigated when picking on October 20. Semi-dried jujube 3kg was randomly picked in each treatment. Single fruit is weighed with an electronic scale with an accuracy of 0.01g.

Inflorescence fruit setting rate (%) = inflorescence fruit number / inflorescence number × 100

Fruit hanging ratio = number of fruit set in inflorescence / number of jujube hanging

Commodity fruit rate (%) = the number of commodity fruits sampled / the total number of samples × 100

Number of commercial fruits = number of set fruits-number of abnormal fruits-number of split fruits

Rate of abnormal fruits (%) = number of abnormal fruits / total number of samples × 100

Fruit cracking rate (%) = number of split fruits / total number of samples × 100%

Edible rate (%) = (sampling weight-jujube kernel weight) / sampling weight × 100

Fruit drop rate (%) = (number of fruit per inflorescence-number of fruit per inflorescence) / number of fruit per inflorescence × 100

3 results and analysis

3.1 effects of ring cutting and ring peeling on fruit setting of grey jujube

Table 1 shows that compared with the control, ring cutting and ring peeling of gray jujube can increase the fruit setting rate and fruit hanging ratio, but reduce the fruit drop rate. The order of effect from big to small is as follows: 1 ring peeling, 3 ring cutting, 2 ring cutting, 1 ring cutting and control. The fruit setting rate of inflorescence in the treatment of ring cutting and ring peeling was significantly higher than that of the control (5.16%). There was no significant difference between 1 ring cutting (14.28%) and 3 ring cutting (12.54%), but significantly higher than that of 2 ring cutting (11.55%) and 1 ring cutting (10.48%). There was no significant difference between ring cutting 3 and ring cutting 1, but there was no significant difference between ring cutting 2 and ring cutting 1. The fruit hanging ratio, the effect of each treatment was the same as the fruit setting rate of inflorescence. The fruit drop rate of the control (22.73%) was the highest, which was not significantly different from that of ring cutting 1 (21.24%). The lowest was 1 ring (5.69%), which was significantly lower than that of ring cutting 3 (13.55%), and that of ring cutting 3 was significantly lower than that of ring cutting 2 (15.63%).

Table 1 effect of ring cutting and ring peeling on fruit setting of grey jujube

Note: different lowercase letters next to the numbers in the same column in the table represent P