Late-autumn tomato cultivation techniques

From a geographical perspective, Guizhou is itself a province composed of karst landforms, with an average altitude of around 1100m across the province. Because its land area is very large, it is very suitable for planting various off-season vegetables. With the adjustment of China's agricultural structure and the continuous development of the agricultural economy, tomatoes have now become one of the main vegetable varieties planted in Guizhou. In the process of summer tomato planting in Guizhou, seedling raising has become a very critical step. Also, because the weather across the whole of Guizhou Province changes very frequently, many difficulties and failures are actually encountered in the process of off-season tomato planting. Therefore, growers especially need to pay attention to the cultivation techniques for off-season tomatoes in Guizhou, and it is hoped that this article can provide everyone with better reference opinions.

1 Preparation before sowing

1.1 Variety selection

In the process of tomato planting in Sinan County, Guizhou, it is especially important to choose high-quality varieties such as 9130, Hongjiangjun, Wangzhongwang, Jintama and many other types. These tomato varieties, which are valued in many places in Guizhou, are not only of superior quality but also have good marketability and disease resistance, and they have performed well in many places including Sinan County, Guizhou.

1.2 Reasonable selection of the seedling-raising site

In the process of late-autumn tomato cultivation in Guizhou, particular attention should be paid to the selection of the seedling-raising site. Choosing a seedling-raising site with higher terrain, better drainage and better ventilation is a good choice. In addition, the following points should also be noted during sowing: first, note that items such as straw curtains and wheat straw should be used to cover above the seedling-raising site, as this can effectively prevent evaporation inside the seedling-raising site caused by excessively high temperatures, after which a greenhouse film can be built on top. In order to make the management of the greenhouse more convenient, we must not build the greenhouse too low; generally, setting the greenhouse height at 80cm and the length at around 6m is most appropriate. And particular attention should be paid to ensuring that no other crops have been planted in the tomato-growing land within three years.

1.3 Disinfecting the seeds

In the process of cultivating tomatoes, the most important thing is to enable the seeds to germinate quickly and uniformly, and to enhance the disease resistance of the seeds themselves in this process. Therefore, before sowing, the seeds should be sterilised and pre-germinated, which can mainly be carried out in the following steps [1]. First, put all the seeds into a bag made of gauze, then place them in water at a temperature of around 50℃ to soak, with a soaking time of about 15 min. After that, place the seeds in a 10% potassium permanganate solution to soak, with a soaking time of about 20min. Finally, once the seeds show white sprouts during sowing, sowing can begin.

1.4 Choosing the right time for sowing

Because the altitude range covered across the whole Guizhou region is very wide, we especially need to choose different sowing periods according to different altitudes. In areas with an altitude below 1000m, the sowing time should be chosen around May to June. In areas with an altitude of 1100m to 1300m, sowing should be chosen in late May. The altitude of Sinan County, Guizhou is about 1302m, so sowing should be carried out from the end of May to mid-June. During sowing, particular attention should be paid to watering the soil. During sowing, about 3 seeds can be sown directly into the hole, or the seeds can be placed directly into nutritional bags; in particular, a layer of sieved nutrient soil should be spread on top at the end, and then the seeds should be gently covered and buried. In order to keep the seeds moist, a small amount of water should be sprinkled above the seeds.

2 Field management

2.1 Before emergence

Before emergence, particular attention should be paid to keeping the seedbed moist, and the condition of the land should be observed at all times to prevent the soil from clumping. Depending on the situation, both ends of the greenhouse do not need to be kept fully ventilated. If high summer temperatures are encountered, the greenhouse films at both ends of the greenhouse should be uncovered so that ventilation can be carried out at any time. Apart from times of high summer temperatures, at other times the time for uncovering the greenhouse film should be controlled between 13:00 and 16:00 in the afternoon. Note that the seedbed should be kept moist at all times; if a lack of moisture is found, then the watering work should especially be arranged in the morning.

2.2 Growth period

In the process of planting late-autumn tomatoes, topdressing is a very important task, and generally a method of 4 to 5 topdressings can be used. Topdressing should first be carried out at a rate of 150 to 210kg per sq m, and afterwards fruit-preserving fertiliser should be added subsequently so as to increase the growth of the fruit. After that, during the large-scale harvesting of the fruit, manure water can subsequently be used for fertilisation, and compound fertiliser can also be applied in combination when necessary. During topdressing, the amount of fertiliser should also be adjusted flexibly according to the growth of the plants.

2.3 Reasonable pruning

In the process of tomato field management, reasonable pruning is a very important step. Timely pruning of branches and leaves can effectively ease the conflict of growth between branches, thereby improving the plants' immunity by allowing them to absorb more sunlight. For plants with a particularly complex structure, we can adopt the method of first retaining the main branch and then removing all the remaining side branches and leaves. On the one hand, this can help the wounds heal better during pruning, and on the other hand, it can also effectively prevent pathogens from spreading widely through the branches and leaves. If during planting it is found that the target plant has already flowered and the fruit above has become smaller due to squeezing, directly affecting the appearance of the tomato, then attention should be paid to pinching it, as only in this way can the normal supply of nutrients to the plant be ensured. Even more attention should be paid during planting to removing leaves that have already become diseased, as only in this way can the plant be ensured to carry out photosynthesis under normal conditions.