The application technology of plant growth regulator is a technology that changes some growth habits of plants through the intervention of chemicals to achieve the expected effect, and it is the application of modern science and technology in planting production. The application of plant growth regulator technology is a great progress in planting technology. Since 1990s, this technology has been gradually applied in the production of vegetables and fruits in China, and the pace of application has been accelerating. The application of plant growth regulators in grape production mainly includes the following aspects:

First, it is used for seedless treatment of seedless grapes. Gibberellin (GA3) was used to induce seed abortion of nucleated grape and transform it into seedless grape. Gibberellin (GA3) is the earliest growth regulator used in seedless grape varieties at home and abroad. The main function of gibberellin (GA3) is to promote plant cell division and cell elongation. Before the grape blooms, gibberellin (GA3) is used to make the pollen and embryo plants develop abnormally, thus turning the nucleated grape into seedless grape. Specifically, diploid varieties such as Rose Dew were soaked with gibberellin (GA3) with a concentration of 50- 100 mg/kg/4 days before full bloom. Tetraploid varieties, such as Kyoho and Xianfeng, are soaked in gibberellin (GA3) with a concentration of 25-50 mg/kg after flowering, with Kyoho in full bloom and Xianfeng in full bloom for 3 days. Whether induced before or during flowering, grapes will become seedless and the fruit will become smaller because of the disappearance of endogenous hormones, so gibberellin needs to be used again in the young fruit stage to make the fruit expand to normal size. In this way, the first treatment of chemical agents induces seedlessness, and the second treatment increases fruit grains, which is the secondary treatment cultivation mode of grape seedless. Generally, the suitable time for the second treatment is 15 days after flowering and 10 days after the first use, the concentration is 25mg/kg (ppm), and the use method is ear soaking. Different varieties have differences in the specific details of using gibberellin (GA3) for nuclear-free treatment, such as concentration and treatment time.

Second, it is used for grape fruit expansion. The second treatment after the seedless grape treatment is mainly used for fruit expansion. Treating seedless varieties with gibberellin (GA3) can not only improve the fruit setting rate, but also promote the fruit growth. The commonly used chemicals for grape fruit expansion are gibberellin (GA3) and pyraclostrobin CPPU. The swelling effect of CPPU on grapes is more obvious than that of GA3, but it also has some side effects, such as delaying fruit ripening, coloring and reducing sugar content. Although GA3 has a slight swelling effect, it is beneficial to berry ripening and coloring. The mixed use of the two drugs has complementary effects. The mixed concentration of CPPU and GA3 as grape swelling agents varies with grape varieties, and GA325mg/kg and CPPU2-5mg/kg are usually used for Kyoho grape. Grape bulking agent can increase the fruit grain number of seedless varieties such as Kyoho and Fujiminori by 10%-40%, and seedless varieties such as seedless Baijixin and seedless Zaohong by 1-3 times. Usage: Seeded grapes should be used 15-20 days after flowering, and seedless grapes should be used once every 5 days and 15-20 days after flowering.

Third, it is used for ear lengthening. Some varieties of grapes have short pedicels and compact fruit grains. In the process of berry expansion, fruit grains are easy to squeeze each other, which leads to irregular ear shape and uneven size of fruit grains, which affects the appearance of ear. In order to solve this problem, ear elongation agent is often used to make the ear loose and the fruit grains uniform, thus improving the commodity value of the fruit. At present, gibberellin is mainly used, and the inflorescence is generally treated before flowering. The specific optimal use time and concentration should be determined according to the grape variety and the type of elongation agent used. For example, when Fujiminori is 5㎝ long, spraying or dipping with 5 mg/kg gibberellin is generally not suitable for premature or near flowering or flowering, otherwise serious grain size may occur; The concentration is not easy to be too high, otherwise it may cause ear deformity.

Fourthly, it is used to inhibit the vegetative growth of grapes, improve the fruit setting rate and improve the quality. For grapes with vigorous plant growth, CCC can inhibit the germination of secondary buds instead of manual pit removal and secondary buds removal, which has the functions of increasing fruit setting rate, increasing yield, improving quality and promoting flower bud differentiation. Used to promote fruit setting, for example, on Kyoho grape, the application period is generally 5- 10 days before grape flowering, and the concentration is 1000-2000 mg/kg. The application method is spraying new buds. In order to control the growth, new shoots are generally sprayed after flowering 1 month, and the concentration is 1500-2000 mg/kg. Note: The weight of single grain is reduced after spraying. In addition, regulating phosphorus and photorespiration inhibitor (sodium bisulfite) also have certain effects. Regulating the utilization of phosphorus in grapes can significantly increase the sugar content of fruits, and has the functions of inhibiting vegetative growth and controlling secondary branches; The use time is one month before the berries are ripe, and the use concentration is 500- 1000 mg/kg. Through experiments, adjusting phosphorus can improve the soluble solids of berries and promote the coloring of colored varieties. Photorespiration inhibitor (sodium bisulfite) can not only improve the fruit setting rate of grapes, but also have good effects on fruit quality, yield and maturity.

5. It is used to promote the coloring and ripening of grapes. At present, products with ethephon and abscisic acid as the main components are widely used in the market, which can promote the early coloring and ripening of berries, and the early time is more than 7 days.

The application of plant growth regulators in grape production is the progress of science and technology, which has attracted more and more attention from researchers and producers, and the varieties put into use are on the rise. However, this technology is still in the process of continuous in-depth research. So we must use it carefully and not blindly. Before use, you must pass the test and master the first-hand information. In the process of use, it must be used scientifically, reasonably and moderately, and it must not be abused blindly, and the frequency and concentration of use should be increased at will. Special attention should be paid to the following issues:

First of all, we should fully consider the safety of plant growth regulators to Staphylococcus aureus. When selecting the varieties of plant growth regulators, we must choose plant hormone products that are allowed to be used in the production of pollution-free green food grapes and produced by fermentation technology, and do not use plant growth regulators produced by chemical organic synthesis, which will not pose a threat to the edible safety of grapes after use. Therefore, when purchasing, you must understand clearly before purchasing, and you can't blindly follow the trend. At present, regulators such as B9 and ethephon are not allowed to be used in the production of pollution-free green food. The use of flufenoxuron, imazalil and 245-T plant growth regulators is also prohibited in EU countries. In addition, attention must be paid to the concentration, allowable use times and safe interval when using them. Too high concentration, too many times or too short safety interval may pose a threat to the quality and safety of Portugal.

Secondly, we should really understand the side effects caused by the use of plant growth regulators, and figure out which varieties can be used and which varieties cannot be used. Not all kinds of plant growth regulators can be used. For example, the swelling agent has a certain effect on European and American hybrids such as Fuji Mino, Gaoqi, Jinfeng and Jingya, and seedless Eurasian seedless varieties such as Bai Jixin, Youseedless and Ruby Seedless. But it is best not to use it on some Eurasian varieties with seeds. Although the grains are slightly enlarged after use, the ripening time is delayed and the sugar content is reduced. If used improperly, the fruit will become smaller, such as jade, August and ruby. Although Rizamat can increase the fruit size after use, it affects the coloring, reduces the sugar content and easily leads to fruit drop after harvest. These varieties should not use expansion agent. In addition, the wonderful seedless Eurasian species, seedless Venus among European and American hybrids, Royal Autumn and other varieties have no obvious effect after use. Most bulking agents are broad-spectrum and suitable for various varieties, but some are special and only suitable for certain varieties. Another example is a seedless agent. Not all varieties with seeds can be treated with seedless agents, and must be screened and determined in the experiment. From the current research, Xianfeng, Cuifeng, Rose Dew, Jufeng, Bud A and other varieties are relatively stable in seedless treatment, with high seedless rate, and the fruit grains reach or approach the untreated size, which has certain utilization value. If the seedless rate is not obvious or unstable after use, and the fruit grains become smaller obviously, it is of no use value. Some varieties are not suitable for seedless treatment because of side effects such as twisted spike axis, cork, thickened and hardened fruit stalk and berry shedding. Inflorescence elongators can be used for varieties with particularly good fruit-setting performance, such as Jingxiu of Eurasian species and seedless Venus of European and American hybrids, but not for Auguste, Victoria, Meirenzhi, Rizamat and Kyoho. In addition, varieties with good fruit-setting performance should not use fruit-protecting agents, which will increase the workload of fruit thinning after use; Paclobutrazol, chlormequat chloride, mepiquat chloride, phosphorus regulation, etc. , only suitable for varieties and orchards that grow vigorously and grow too fast, not suitable for varieties and Portuguese orchards that grow moderately. In short, which varieties can use plant growth regulators and which varieties can't use plant growth regulators should be determined through experiments.