Tobacco Seedling
In our country, tobacco varieties are grown by first harvesting seedlings and transplanting them into the field. Being able to grow the seedlings required for planting in a sound, alive, well-developed and well-developed form on time is one of the important production stages of today's tobacco industry. One of the factors affecting productivity and quality in tobacco farming is largely due to the ability to prepare healthy, well-developed, well-rooted, hardy and sufficient seedlings in a timely manner. Failure in the seedbed can sometimes lead to the field being partially or completely empty, delaying planting and disrupting the harvest.
In tobacco cultivation, the necessity of obtaining seedlings suitable for planting in the field is due to the reasons listed below.
Since tobacco seeds are very small in size, they germinate and complete their development by taking care in special places.
In order for seeds to germinate , a temperature of at least 12–14 ° C is required and this temperature can be provided in warm seed pads.
Since the vegetation period of the tobacco plant is long, it is possible to enter the field early in the spring and to benefit from the summer temperatures as much as possible and to ensure that the leaves dry as summer dry in sunny and rainy weather without getting caught in autumn rain, but by planting tobacco in the field as a seedling.
Factors such as the fact that the seedlings are located in a narrow area as a seedling area, disease and pest control within a period of at least 45 to 60 days, maintenance and labor can be done cheaper and easily are factors in the development and development of seedlings.
Tobacco seedbeds are divided into three in terms of how they are made.
1- Cold pillows (black pillows): Used in regions with warm winter and spring. It is open to sudden frost and hail because it is grown completely outdoors.
2- Warm pillows: These are the pillows covered with nylon in order to preserve the moisture and temperature in the regions where the winter season is hard and the spring is frosted. It is more advantageous compared to cold pillows as seedlings can be grown 1-2 weeks ago.
3- Hot pillows: They are not used in our country's tobacco industry. Warmth is maintained by spreading fresh horse manure on the seedbed floor and is kept covered continuously. It can be used in tobacco areas with cold climate.
In tobacco seedling cultivation, if the following points are taken into account, it may be possible to obtain a quality and efficient product.
1-Depending on the weather conditions and the cover material used in the seedbed, the seedlings become able to be planted in the field 45-60 days after sowing. This period should be taken into consideration in the seedbed facility and seed planting. The dates of April 15 - May 20 in Denizli are considered as the ideal time for tobacco planting. Sowing seeds earlier is a waste of time and effort. When planting early, the seedlings will be grown on days when the climatic conditions are not yet suitable for planting seedlings, but they will continue to grow in the nursery and will cease to be seedlings. Such seedlings should never be planted in the field. On the other hand, the soil temperature should be 12-14 ° C for the seed to germinate in the seedbed. Even if it is planted in a very early period, since the soil temperature will not reach the desired level, the seeds will not germinate and some seeds will rot , germination will not be an example.
2- Choose the seedbed location well. Install it in south facing, strained soils. Seedling pillows must be made 15 cm above the ground level, as seen in the photo below. Thus, it will be possible to remove excess water from the root area and aeration of the root, and the possibility of diseases such as root rot and collapse will be reduced. The seedbeds are 100–120 cm wide. 10–12 m in length. should be. While preparing the seedbed areas with specified dimensions, 1-1.5 kg of compound fertilizers should be mixed preferably 15-15-15. Either the seedbed soil or the seedbed place should be changed against diseases and pests.
The seedbeds and the mortar are also disinfected against soil-borne diseases, underground pests, nematodes and weed seeds. Metam Sodium (liquid) or dazomet (powder) active ingredient fumigants are widely used. The recommended amount is applied to the seedbed and the active substance is mixed with water in 10-15 cm. It is kept closed for at least 2 weeks by covering it with a nylon cover. In the 3rd week, the nylon covers are opened and ventilated. The seedbed area, which remains open for 2 weeks, is ventilated with a rake or hoe. With this process, the seedbed disinfection process is completed. When the odor disappears, seeds can be planted. Seed deaths occur in seed sowing in seedbeds that are not well ventilated.
Fumigants applied in the nursery pose dangers for human, animal, plant and environmental health. These applications should be carried out by individuals and organizations that have a fumigation operator certificate issued by the Ministry of Agriculture.
3-As shown in the figure below, the middle part of the seedling pillow should be made slightly higher to prevent water accumulation on the pillow face.
4-Seed bed or seedling mortar should not consist only of barn manure or just soil as in some regions. The mortar , which is made of raw soil, shaft and barn manure by taking and mixing each in equal amounts, is an ideal element to provide the temperature required for germination, to keep enough water in the root zone and to aerate the roots. Prepare the seedbed mortar well (1 part burnt manure, 1 part sand, 1 part soil).
5-First of all, we should prefer to use certified tobacco seeds that we collect from the plants we like from our own fields or that are produced by the Ministry of Agriculture Menemen Research Institute or tobacco companies.
6-10-12 thousand seeds come in 1 gram. In practice, it is accepted that 60-70% of this seed germinates and 6-8 thousand seedlings will be formed. It is assumed that half of these seedlings, ie 3-4 thousand of them, will become seedlings that can be planted in the field. In our region (Denizli), 20-25 thousand seedlings are planted in a decare area depending on the cultivation of the field and its tempering condition. In this case, instead of a cup of tea glass or full of seeds, it is sufficient to make a 5 m² seedbed for one decare tobacco field by sowing 1-1.5 grams of seeds per square meter. The seed to be sown should be mixed with 30-40 times fine stream sand or wood ash and scattered evenly in the seedbed. After planting, the seed should be sprinkled with cover manure (burnt sifted sheep or goat manure) and pressed. It should not be forgotten that sowing too much seed in a unit area, that is, sowing frequently, increases the risk of the collapse disease.
7-After soaking, keeping the seeds cracked or cracked for a few days in a warm environment and then sowing is a method that can be applied if it is late in the seedling facility and seed planting. Because this practice carries the danger of disease occurrence and a decrease in the germination percentage.
8-The seedbed surface must be kept moist continuously from seed planting to the completion of germination. Before the seeds germinate and when the seedlings are small , water should be given frequently and gradually , as the seedlings grow, sparsely but abundantly.
9-It is important to start the pesticide struggle before the emergence of the disease in the seedbed, not after the disease. For this reason, after the germination and emergence are completed, regular spraying should be done against diseases that are common in seedbeds such as blueberry and collapse.
10- It is very important to ventilate the seedbed in order to prevent disease. In sunny weather and when the sun is steep, the seedlings should be opened, sunbathing and aeration of the seedlings should be provided. As the weather gets warmer, open the nylon cover during the day and close it at night.
11-Do not irrigate in the evening. It should be remembered that excessive watering causes wilting and heavy growth in seedlings.
12-Irrigations are generally made in the morning, so that the seedlings can enter the night dry and not affected by the night cold. 7 - 10 days before planting, watering should be reduced and seedlings should be left open at night. In this way, the seedlings are cured and adapted to external conditions.
13-If a properly prepared mortar is used, the seedlings are fed normally and continue to develop. Therefore, there is no need to use chemical fertilizers in the nursery. However, if the development is delayed for any reason (the seedlings turn yellow, do not show the expected length), the seedlings should be given 1-2 times a syrup to be prepared with barn manure or chemical fertilizers and then irrigated slightly.
Sherbet preparation: 130 gr Ammonium Sulphate, 310 gr Superphosphate, 50 gr Potassium Sulphate, 10 gr Magnesium Sulphate fertilizers are dissolved in 100 liters of water.
14-As the seedlings grow in size, cover fertilizer should be given and irrigated, and root development should be encouraged.
15-Rapidly growing and over-sized seedlings should be removed 1-2 weeks before planting (taking a guide) and the seedlings should be made uniform.
16- It should not be neglected to clean the seedbed by removing especially the broad-leaved weeds emerging from the seedling bed from time to time. Aphids and thrips can be seen in the 4-leaf stages of the seedlings. It is important in combating the spotted wilt virus disease transmitted by thrips. Because thrips are very small, they may not be visible by eye. Before the damage caused by the emgi is seen, it should be tried to be detected by looking closely and carefully on the lower and upper surfaces of the seedling leaves.
17-It is not advisable to buy the seedlings we need from people who sell ready-made seedlings instead of growing them personally. By law, this type of seedling sale is prohibited. With such behavior:
- We may have filled our field with a type or type of tobacco that is not suitable for our region.
- We can come face to face with variety or type confusion.
- We can infect our field with some diseases and pests with the seedlings themselves or the soil in the seedling roots.
18- Seedbeds are irrigated before dismantling. The grown seedlings are very gently pulled from the seedlings and taken to the field where they will be planted. While the seedlings are pulled, they should be pulled by holding the leaves.
