西北农林科技大学：《植物营养学》课程教学资源（PPT课件讲稿，英文版）Chapter 09 Fertilizers and environmental

Chapter 9 Fertilizers and environmental

Fertilizers and Environmental Chapter 9

The principles of application fertilizers Law of the Minimum: the crop's yield is restricted by the lack of one element, even Mg Cu Zr Mr Mo Ca though there may be sufficient quantities of all the other elements

The principles of application fertilizers Law of the Minimum:the crop’s yield is restricted by the lack of one element, even though there may be sufficient quantities of all the other elements

The principles of application fertilizers Law of Diminishing Return Yield 报酬递减律 the response of a plant to the addition of a growth will become smaller and smaller as Kg N 100120 the amount of the growth factor increases

Law of Diminishing Return 报酬递减律 the response of a plant to the addition of a growth will become smaller and smaller as the amount of the growth factor increases The principles of application fertilizers

Yield or growth cure Deficient Sufficient Toxicity 一6 Relative Follar Nutrient Content

Yield or growth cure

Fertilizer use and agricultural production Number of Fertilizer people consumption supported by Grain yield kg NPK per Year one hectare per hectarehectare 1800 0.8 0.73 1875 1.3 1.20 3.1 1900 1.6 1.84 15.6 1925 2.28 39 1950 3.3 98 101.9 1975 4.6 4,43 233.5 1978 4.5 4.63 2558

Fertilizer use and agricultural production Year Number of people supported by one hectare Grain yield per hectare Fertilizer consumption kg NPK per hectare 1800 0.8 0.73 - 1875 1.3 1.20 3.1 1900 1.6 1.84 15.6 1925 2.1 2.28 43.9 1950 3.3 2.98 101.9 1975 4.6 4.43 233.5 1978 4.5 4.63 255.8

Crop Quality and application fertilizer The major factors that control crop quality are genetically controlled, but environmental and nutritional factors do have some influence

The major factors that control crop quality are genetically controlled, but environmental and nutritional factors do have some influence. Crop Quality and application fertilizer

Crop Quality and application fertilizer The additions of N at flowering increased grain yield and baking quality. This may not be true in dry areas +40 kg N/ha+60 kg N/ha at flowering at flowering 80kgN/hostage stage Yield (tonnes/ha) 4.59 4.98 5.24 Protein 1.9 2.7 content % o 13.3 Sedimentation 28.0 30.0 34.0 value

80 kg N/ha +40 kg N/ha at flowering stage +60 kg N/ha at flowering stage Yield (tonnes/ha) 4.59 4.98 5.24 Protein content % 11.9 12.7 13.3 Sedimentation value 28.0 30.0 34.0 The additions of N at flowering increased grain yield and baking quality. This may not be true in dry areas. Crop Quality and application fertilizer

Crop Quality and application fertilizer In potatoes, K increases the translocation of carbohydrates from the leaves to the tubers resulting in an increase in the starch content of potatoes K also increases the content of citric acid which reduces the occurrence of black K K+ spot in potatoes

In potatoes, K increases the translocation of carbohydrates from the leaves to the tubers resulting in an increase in the starch content of potatoes. K also increases the content of citric acid which reduces the occurrence of black spot in potatoes. Crop Quality and application fertilizer

Crop Quality and application fertilizer The quality of oil crops may be affected by N nutrition The oil content of canola seeds was reduced by high levels of n Nitrogen Seed yield Seed wt Oil content rate (g/pot)(mg/seed) % DM LOW 0.0 3.0 468 High 18.6 3.6 41,7

The quality of oil crops may be affected by N nutrition. The oil content of canola seeds was reduced by high levels of N. Nitrogen rate Seed yield (g/pot) Seed wt (mg/seed) Oil content % DM Low 10.0 3.0 46.8 High 18.6 3.6 41.7 Crop Quality and application fertilizer

Crop Quality and application fertilizer NO3 NO2 during storage and processing of fruits and vegetables NO3→NO, in the stomach NO2 may be further transformed into cancer-causing chemicals in the human body. Therefore NO3 in fruits and vegetables is a health concern

Vegetable and Fruit Quality NO3 - NO2 - during storage and processing of fruits and vegetables NO3 - NO2 - in the stomach NO2 - may be further transformed into cancer-causing chemicals in the human body. Therefore NO3 - in fruits and vegetables is a health concern. Crop Quality and application fertilizer