Sunflowers are cross-pollination crops. In recent years, there have been many plantings in different parts of the country. In some places, attention has not been paid to the field selection work. There have been problems such as mixed degradation of varieties, poor quality, and low oil content. The yield and quality of sunflower seeds are very high. Great influence. At present, the sunflower is about to mature. It is necessary to do a good job of sunflower field selection.
According to various experiences, field selection prior to sunflower harvest is a simple and effective method. According to the pilot survey, the yield of seeds planted through field selection is 20%-25% higher than that without seed selection, and the growth and development progress is even and the maturity is the same, which creates favorable conditions for timely harvesting.
First, field selection should seize four links
1. To determine the suitable varieties for local planting, select plants with special characteristics of this species.
2. Choose disease-free live plants and plants with no branches, large disk, full seeds, and medium height.
3. Select convex and slightly convex disk, the disk inclination and the stem into a 45-70 degree angle is better. Because the disk with small inclination is not very strong, it is also vulnerable to damage by birds and pathogens. When the mature seed disk is buried in the leaf curtain, it is easy to mold and inconvenient to harvest.
4. After removing the faceplate, it should be transported separately, aired separately, threshed individually, and stored for a single time.
Second, select good varieties. Sunflower is divided into oil sunflower and sunflower. The oil sunflower is short and has small grains. It is mainly used for oil extraction. The sunflower has higher plant size and large grains. It is generally used for foraging or as a food additive. Oil sunflower is best to use high-yield, high-oil hybrids, such as "white sunflower hybrid No. 4", "Guikuza No. 1", "Hungary No. 4", etc. Sunflower can be used "white 97-1", " "Indigo", "Changling Dadeng", etc. The advantage of these varieties is that they are resistant to disease, have very few branches, do not need to fight, have high yields, and have good merchandise.
Third, the selection method. During the middle and late stages of sunflower growth, combining snoring and artificially assisted pollination, select the plants that are free from decentralization, have no harm to pests, have the same appearance as the species, have the same plant height and maturity, and have a medium-sized disk (also known as standing poles). Look at the head and pick it up separately. Which part of the sunflower is good? In a medium-sized (diameter 19 cm) sunflower dish, there are 28 rounds of about 1700 seeds. Which part of the seed is actually good for seeds? Tests by scientific research departments showed that the fruits in the outer ring of the flower disk grew full and full, but after seeding, the roots of the plants that grew were underdeveloped, with short fibrous roots and few root hairs. The water and fertilizer absorption capacity was low, and drought resistance and lodging were not found. Although there are many fruits, but the seeds are thin, the seed germination rate is low, the seedlings grown are not neat, thin and thin; the fruit in the middle circle of the flower disk, the grain is moderate, is not big or small, is full and full, and the nutrient content is high. Take this Some fruits are seeded, the grown seedlings are strong, the plant root system is developed, and the hull rate is low and the oil content is high. From this it can be seen that the fruit in the middle circle of the sunflower disk is best kept as seeds.
Fourth, timely harvest. About 7 weeks after the flowering period of sunflower, the plasticity material no longer increases, the physical properties stop changing, and the seed moisture content has dropped to about 30%. From the external morphology, stems, upper leaves of the plants, and discs on the back turned yellow and tongue-shaped flowers turned yellow-brown. The tubular flowers fell off and the hulls became hard. This time it reached a mature stage and should be harvested in time.
Fifth, keep well stored. When the moisture content of the seeds reaches 8%-9%, they are stored in bags. The winter temperature is maintained at 3°C-7°C, and the summer temperature does not exceed 25°C. In this way, the seed germination rate can be maintained at about 95% within 1-3 years. The fourth year fell to 85%-95%, while in the fifth year it dropped rapidly to 57%-85%. Therefore, the storage life of sunflower seeds should generally not exceed four years.
According to performance characteristics and scope of application, medical Masks can be divided into: medical protective masks, medical surgical masks, general medical masks.
Medical protective masks: Medical protective masks are suitable for the protection of airborne respiratory infectious diseases by medical personnel and related staff. Wear when in contact with airborne or droplet-borne respiratory infections. It can filter the particles in the air and block droplets, blood, body fluids, secretion droplets, etc. It is a disposable product. Medical protective masks can prevent most bacteria, viruses and other pathogens. WHO recommends that medical personnel use protective masks against particulates to prevent virus infection in the hospital air.
Kids Safety Mask,Children Face Mask,Kids Medical Mask,Kids Disposable Face Mask
BIQIAO MEDICAL TECHNOLOGY(HENAN) CO.,LTD , https://www.medical-technology.net