Several measures and high-yield cultivation techniques for early sowing of summer sesame

Most of the main producing areas of sesame in China are planted in summer, and the yield is low and unstable for a long time, which is related to frequent disasters, but the more important reason is that the sowing date is late, the growth period of sesame is short, and the climate resources are not fully and reasonably utilized. in order to solve this problem, in recent years, we have carefully studied how to sow in advance and supporting cultivation techniques of summer sesame, and preliminarily summed up a set of high-yield cultivation techniques.

1 Analysis of the reasons for increasing yield by early sowing of sesame

1.1 make full use of climate resources the main sesame producing areas in China, including Huaibei, Jianghan Plain and Nanyang Basin in Henan, Hubei and Anhui provinces, are located in the middle latitudes of the East Asian continent, with typical monsoon climate characteristics. From late May to early September, it is the most abundant period of light and heat resources in a year, and it is also a season suitable for the growth and development of sesame. The sowing date of summer sesame is advanced to mid-May and about June 1 at the latest, so that the climate resources in this stage can be utilized to the maximum extent. This is more than the effective accumulated temperature and sunshine hours of the whole growth period of sesame sown in ploughed fields after wheat harvest. Sesame is a kind of crop that likes temperature and light, and has the habit of continuous growth and continuous flowering when the climatic conditions are suitable. Due to the increase of effective accumulated temperature and sunshine hours, it laid the foundation for realizing high yield of summer sesame.

1.2 avoiding or mitigating the effects of disastrous weather, sesame seeds can generally emerge in late May and bud before the end of June. the whole seedling stage has low temperature, sufficient sunshine and dry atmosphere, which is conducive to the early development and steady growth of sesame seeds. After July, gradually enter the flood season, as long as we do a good job of drainage and waterlogging prevention, high temperature and abundant precipitation are conducive to the exuberant growth and flowering and capsule formation of sesame. Since the middle of August, the flood season has passed and the temperature has obviously decreased, but at this time the sesame is close to the top and the final flower, and the relatively dry weather is beneficial to the filling and fruiting of sesame. Therefore, early sowing sesame showed high plant height, low legs, many capsules, large capsules, full grains, high 1000-grain weight and short yellow tip.

2 several measures to realize early sowing of summer sesame

2.1 interplanting sesame with wheat ridge

2.1.1 the best time for interplanting sesame seeds in wheat ridge is around May 20, which is the best time for interplanting sesame seeds in wheat ridge. In this period, compared with the wheat harvest, the rainfall is guaranteed, the soil moisture is good, and the atmospheric evaporation is low, which is beneficial to sowing the whole sesame seedling. The effective flowering period of interplanting sesame in wheat ridge is at least 10-15 days longer than that in ploughing after wheat, which lays the foundation for high yield of summer sesame.

2.1.2 Variety selection and planting method of wheat varieties with short stem, early maturity and high yield (such as Yumai 18 and Zhengmai 9023), wide row 24cm and narrow row 12cm were selected in the previous crop. In wheat management, we should control water and fertilizer and implement chemical control technology to prevent wheat lodging. Chemical weeding was used to eliminate weeds in wheat field in order to facilitate the field operation of wheat ridge interplanting. It is not suitable to plant sesame seeds in wheat fields sprayed with metformin pesticide after December.

2.2 interplanting sesame seeds between garlic rows

2.2.1 the best time for interplanting sesame in garlic field around May 15 is the best time for interplanting sesame in garlic. During this period, 90% of the leaves of garlic enter the senescence period, which is a favorable period for sowing sesame in the field.

2.2.2 the planting method of interplanting sesame in garlic field is generally 21~24cm, and the sowing method of sesame is 2 ∶ 1. In the case of insufficient soil moisture before sowing sesame seeds, garlic can be watered once to send old water, which is beneficial to sowing the whole sesame seedlings.

2.3 sowing sesame seeds with iron stubble

2.3.1 sowing wheat in time after harvest, sowing in time according to soil moisture. The sesame sown in this period and the sesame sown in the ploughing field can enter the flowering stage 5-7 days in advance, otherwise the sesame sown in the ploughed field will enter the high temperature and rainy season soon after emergence, resulting in plant overgrowth and low temperature in the later stage, which will affect the filling maturity of sesame. Therefore, the planting of sesame seeds after wheat ploughing tends to form short plants, high legs, sparse capsules, small capsules, seed chaff and yellow tips.

2.3.2 the method of sowing sesame in wheat stubble should be sowed in soil moisture after harvest. The method is as follows: under the condition of sufficient ① picking, sow diammonium phosphate (or monoammonium phosphate) 10~15kg first, and then sow the seeds forward. ② sowing technology is good enough to sow diammonium and sesame seeds together. Remember that the mixed sowing of chemical fertilizer should not be excessive, otherwise it will affect the emergence of sesame seedlings. In the case of insufficient ③ moisture but does not affect seedling emergence, sow sesame seeds first, and apply the same amount of chemical fertilizer from sesame emergence to budding stage. The above three sowing methods should be grinded in time to preserve soil moisture after sowing, which is beneficial to seedling emergence.

3High-yielding cultivation techniques of sesame

3.1 the results of reasonable close planting density test showed that the planting density of high yield field should be controlled at 8000 ~ 9000 plants per mu, and the general soil fertility should keep 10000 ~ 12000 seedlings per mu.

3.2Scientific fertilization of sesame should be scientific, and its fertilization principle is to control nitrogen fertilizer and increase potassium fertilizer. Under general medium soil fertility conditions, pure nitrogen 5~6kg, phosphorus pentoxide 5 ~ 6kg, potassium oxide 3~5kg are applied per mu, 10~15kg diammonium phosphate can be used as seed fertilizer during sowing, 5~7.5kg urea is applied as flower bud fertilizer after budding, potassium fertilizer should be properly supplemented in potassium deficient soil. When it was found that the plants were de-fertilized during the topping period of sesame, the combination of rain or irrigation with urea 1.5kg per mu promoted sesame grain filling and reached the full grain weight of the upper seed.

3.3 Field management

3.3.1 after sesame emergence at seedling stage, the previous crops have been harvested and weeding should be carried out in time to prevent seedling famine and grass famine. (4) after fixing the seedlings of true leaves, topdressing and sealing roots were carried out under the condition of sufficient soil moisture.

3.3.2 drought prevention and drainage of sesame fields, according to the topography, dig a good soil moisture ditch, waist ditch, to achieve three ditches connected, so that open water can drain, dark water can discharge. After entering the flowering stage, it has a great impact on the growth of sesame. If the plant leaves are found to wilt in the afternoon, it should be irrigated in time to prevent growth stopping, falling flowers and buds due to drought, and ending flowers and capping ahead of time.

3.3.3 during the growth of sesame, we should focus on the comprehensive control of diseases and insect pests, especially take a variety of comprehensive control in chemical control, closely control underground pests at seedling stage, and spray once every 7 days after setting seedlings. The drugs used are generally carbendazim, methyl thiophanate, virus A, Lesbon, enemy killing and so on. Rotational spraying was carried out, and potassium dihydrogen phosphate, borax and anti-aging hormones were applied in full bloom, which not only reduced the loss of diseases and insect pests, but also met the fertilizer requirements of sesame in the middle and later stage and delayed senescence.

3.3.4 the results of the experiment of topping, leaf protection and timely harvest showed that the yield of sesame topping was about 10% higher than that of no topping, the time of topping was around the end of July, and the iron stubble sowing sesame on August 5-7 (7 days before the Beginning of Autumn) was suitable. The topping length is less than 1 cm. It is very important to protect the leaves of sesame near the end of flowering. The yield of defoliation is 23.3% lower than that of non-defoliation. The earlier the defoliation time is, the greater the yield reduction is. The lower capsule of the sesame plant can be harvested when the capsule or the seed in the middle of the plant shows the inherent color of the seed. Small bundles are dried after harvest, and stacking is strictly prohibited to ensure the color of the seed.