Reduce nitrogen fertilizer for rice to increase rice quality

(Baonghean) - Applying too much nitrogen fertilizer to rice will reduce rice yield, rice grain quality, and affect the ecological environment of rice fields. Therefore, scientists have collaborated with a number of farmers to conduct experiments on a number of rice fields to determine the appropriate amount of nitrogen fertilizer.

In fact, farmers have long used too much urea fertilizer for rice, causing the rice plants to grow wildly, lack light, leading to pests and diseases, and the plants are prone to falling during the flowering and grain formation stages.

Therefore, farmers have to spend more on labor and pesticides to prevent it. When rice falls over, it reduces productivity and increases the rate of empty grains, poor rice quality, low selling price, and reduced profits.

Excess nitrogen also pollutes the environment due to the amount of nitrate flowing into water sources. How much nitrogen is enough for rice is of particular interest to scientists in the agricultural sector, in order to reduce investment costs and increase rice productivity.

Farmers in Phuc Thanh commune (Yen Thanh) apply nitrogen fertilizer before planting rice.

Mr. Nguyen Quang Tung's family - a farmer in hamlet 8, Hung Long commune (Hung Nguyen), one of the households with fields implementing the experimental model "Determining the appropriate amount of nitrogen fertilizer for rice plants" said: With 1 sao of rice field, in the last summer-autumn crop, the family fertilized 5 quintals of manure, 7.25 kg of urea, 20 kg of phosphate, 6 kg of potassium and 25 kg of lime powder (for hybrid rice) and 5 quintals of manure, 6.25 kg of urea, 20 kg of phosphate, 5 kg of potassium and 25 kg of lime powder (for pure rice). During the care process, it was shown that due to the low amount of nitrogen fertilizer, the amount of manure, phosphate and potassium fertilizer was guaranteed and balanced, so the rice plants were strong and did not fall over, even when affected by some recent storms. The rice had few pests and diseases, the effective tillering rate, and the grain was high. The yield of hybrid rice reached 299 kg/sao, and that of pure rice reached 304 kg/sao.

Meanwhile, the rice area not following the model has a yield of only 282 kg/sao of hybrid rice and 280 kg/sao of pure rice. According to Mr. Tung, the sectors should continue to implement the next 1-2 crops to confirm the effectiveness, and at the same time propagate and convince farmers to apply.

Yen Thanh district is the rice granary of the whole province, with over 12,000 hectares of land for two rice crops per year. Every year, farmers here use thousands of tons of nitrogen fertilizer to fertilize rice plants. Mr. Nguyen Van Duong - Head of the district's Department of Agriculture and Rural Development said: The situation of farmers using too much nitrogen fertilizer to fertilize rice plants is still common in some localities, leading to green rice plants, high rate of empty grains, low rice yield, and low quality of rice grains.

Therefore, it is very necessary for farmers to know how much nitrogen fertilizer is enough for rice, helping them reduce input costs and increase rice productivity. However, determining how much nitrogen fertilizer is appropriate for rice is really difficult, because it depends on each type of land: deep fields, shallow fields, sandbanks... Therefore, the experimental model "Determining the appropriate amount of nitrogen fertilizer for rice in Van Thanh, Bac Thanh in the past few crops has only been applied to certain areas and has not been widely deployed.

Agricultural staff of Muong Noc commune (Que Phong) guide people on how to properly care for rice and limit harmful pests and diseases.

Engineer Tran Minh Doan - Nghe An Agricultural Science Association, head of the experimental project, said: This project aims to increase income by 7 - 10% for rice growers, improve rice quality, and at the same time protect the ecological environment of rice fields.

This topic was surveyed in Van Thanh, Bac Thanh (Yen Thanh), Thanh Dong, Thanh Luong (Thanh Chuong), Hung Long, Hung Thong (Hung Nguyen). After implementing the topic "Determining the appropriate amount of nitrogen fertilizer for rice in some key rice production areas in the province", it was found that different amounts of nitrogen fertilizer cause different levels of pests and diseases in rice fields. The more nitrogen fertilizer is applied, the more pests and diseases are caused in rice fields.

However, according to Agricultural Engineer Tran Minh Doan, to have a more accurate conclusion, the Department of Agriculture and Rural Development needs to build a number of more models of 5 - 10 hectares, with hybrid rice varieties, pure rice in the summer-autumn and spring crops in key rice areas, in the direction of reducing an average of 40 - 45 kg of urea/ha.

Through investigation, survey and research of 3 production crops in 6 communes of 3 districts, it shows that, on the experimental area, the highest yield is determined: Summer-autumn hybrid rice is fertilized with 145 - 150 kg of nitrogen/ha, spring hybrid rice is fertilized with 175 - 180 kg of nitrogen/ha. For summer-autumn pure rice, fertilize with 125 - 130 kg of nitrogen/ha, spring pure rice is fertilized with 155 - 160 kg of nitrogen/ha. That amount of nitrogen is applied 3 times/crop: 1 basal application and 2 top dressing applications.

Xuan Hoang