Crop responses to K application and K nutrient balance Ping He 1,2, Shihua Tu 1,3, Fang Chen 1,4, Shutian Li 1,2, Jiyun Jin 1,2 1 IPNI China Program 2 Institute of Agricultural Resources and Regional Planning, CAAS, Beijing 3 Soil and Fertilizer Institute, Sichuan AAS, Chengdu 4 Wuhan Botanic Garden, CAS, Wuhan
The role of K application Quality improvement Yield and benefit improvement Water use efficiency improvement Interaction with N K Build up soil K Drought Resist Pests and diseases resist Lodging resistant
Outlines Crop responses to K application Yield responses Profitability Agronomic efficiency (AE) K nutrient balance CoAon 3% Others 16% Wheat 14% Wheat Maize Rice Soybean 8% Maize 16% Fruit Vegetables Tuber Tuber 9% Rice 17% Soybean CoAon Vegetables 11% Fruit 6% Others
Data sources IPNI field research 21-21 Different crop types Cereals Vegetables Fruit trees Oil crops 22 26 433 185 Tuber crops Others
Ranges of K application - Cereal crops Crops No. of trials Regions K applicaion rate (kg K 2 O/ha) Wheat 26 SW 68-15 12 SE 9-225 6 NW 45-15 16 NC and NE 12-167 Maize 45 SW 38-15 3 SE 9-12 16 NW 3-3 81 NE 75-129 85 NC 76-151 Rice 45 SW 6-225 17 SE- early 75-225 13 SE- mid 15-18 25 SE- late 61.5-225 16 NW 75-15 27 NE 75-18
Ranges of K application - Vegetables Regions No. of trials Crops K applicaion rate (kg K 2 O/ha) SW 4 Cabbage 6-225 2 LeAuce 226 4 Turnip 6 3 Chili pepper 26 SE 18 Vegetables 9-45 17 Lotus root 225-45 5 Water bamboo 225 NW 12 Tomato 54-3 5 Celery 15-225 14 Chili pepper 45-3 13 Cabbage 27-225 NC and NE 11 Tomato 15-6 12 Cabbage 18-27 11 Cauliflower 75-225 6 Celery 15-225 11 Cucumber 18-675
Ranges of K application-fruit trees Regions No. of trials Crops Ranges of K application (kg K 2 O/ha) SW 19 Banana 45-12 3 Papaya 72-96 SE 2 Orange 195-9 2 Chestnut 15 NW 13 Grape 9-1 5 Apple 33-1 7 Kiwi 24-1125 High K-demanding crops: Banana N:P 2 O 5 :K 2 O=1:.25:2.5 Kiwi N:P 2 O 5 :K 2 O=1:.43:2.6 Apple N:P 2 O 5 :K 2 O=1:.45:1.8 Grape N:P 2 O 5 :K 2 O=1:.34:1.45
Ranges of K application-oil crop Regions No. of trials Crops K application rates (kg K 2 O/ha) SW 11 Rape 12 5 Rape 9-15 SE 14 Peanut 9-135 2 Soybean 9 19 Sesame 75-225 NW 7 Sunflower 6-15 NC and NE 7 Peanut 2-18 22 Soybean 6-9
Ranges of K application -Tuber and other crops Crops Regions No. of trials K application rate (kg K 2 O/ha) Potato SW 18 67-24 NW 77 3-3 Sweet potato SE 6 18 Cotton SE 3 225-27 NW 1 3-9 Tea SE 2 195-3 High K-demanding crops: Potato N:P 2 O 5 :K 2 O=1:.46:1.78 CoAon N:P 2 O 5 :K 2 O=1:.46:1.48 Potato distribution
Yields of cereal crops Average yield (kg/ha) 12 1 8 6 4 2 With K SW SE NW NC and NE Without K SW SE NW NE NC SW SE SE SE NW NE Wheat Maize Rice Mean yield with K was 8139 kg/ha, while that without K was 7148 kg/ha Yield increased by 8.6%-21.8% (14.%)
Yield of vegetables Average yield (t/ha) 14 12 1 8 6 4 2 With K Without K Cabbage Lettuce Turnip Chili pepper Vegetables Lotus root Water bamboo Tomato Celery Chili pepper Cabbage Tomato Cabbage Cauliflower Celery Cucumber SW SE NW NC and NE Yield was 63.2 t/ha and 54.7 t/ha with and without K application K application enhanced the yield by 6%-21.5% (15.5%)
Yields of fruit trees Average yield (kg/ha) 6 5 4 3 2 1 With K Without K Banana Papaya Orange Chestnut Grape Apple Kiwi SW SE NW Yield with was 32.5 t/ha and yield without K was 26.4 t/ha K application increased yield by 22.8%
Yields of oil crops Average yield (kg/ha) 5 4 3 2 1 With K without K Rape Rape Peanut Soybean Sesame Sunflower Peanut Soybean SW SE NW NC and NE Yields with K and without K were 437 kg/ha and 2614 kg/ha K application increased yield by 16.5%
Yields of tuber crops Average yield (t/ha) 4 35 3 25 2 15 1 5 With K Without K SW NW SE Potato Sweet potato Yields with K and without K were 28.1 t/ha and 23.8 t/ha K application increased tuber crops yield by 8%-2% (17.7%)
Yield responses of cereal crops Yield response to K (kg/ha) 18 16 14 12 1 8 6 4 2 SW SE NW NC SW SE NW NE NC SW SE SE SE NW NE and NE Wheat Maize Rice Yield responses were 583-1672 kg/ ha, averaged 99 kg/ ha Wheat, maize and rice in SW mostly had larger yield response than other regions Yield responses to K on wheat, maize and rice were.7~1.2,.7~1.7 and.6~1.2 t/ha, respectively Yield response = Yield of OPT plot Yield of omission plot
Yield responses to K application of vegetables Yield response to K (t/ha) 25 2 15 1 5 Cabbage Lettuce Turnip Chili pepper Vegetables Lotus root Water bamboo Tomato Celery Chili pepper Cabbage Tomato Cabbage Cauliflower Celery Cucumber SW SE NW NC and NE Yield responses ranged from 2.2-22.5 t/ha, averaged 8.5 t/ha Tomato, celery and cabbage in NW, cucumber in NC and NE had higher yield response
Yield responses to K application of fruits Yield response to K (t/ha) 12 1 8 6 4 2 12 8 8 6 5 3 Banana Papaya Orange Chestnut Grape Apple Kiwi SW SE NW Yield responses varied greatly with.2-11.8 t/ha, averaged 6. t/ha
Yield responses to K application of oil crops Yield response to K (kg/ha) 7 6 5 4 3 2 1 676 Rape 352 361 Rape Peanut 258 Soybean 162 Sesame 69 Sunflower 551 Peanut 492 Soybean SW SE NW NC and NE Yield responses ranged from 162-676, averaged 433 kg/ha Rape in SW, sunflower in NW, peanut and soybean in NC and NE had relative high yield response to K.
Yield responses to K of tuber crops Average yield response to K (t/ha) 6 5 4 3 2 1 5 4 3 SW NW SE Potato Sweet potato Yield response of potato to K in NW was higher than SW
Net benefit of cereal crops Average of net benefit (Yuan/ha) 5 45 4 35 3 25 2 15 1 5 SW SE NW NC and NE SW SE NW NE NC SW SE SE SE NW NE Wheat Maize Rice Great variation for profitability (48-4578 yuan/ha, averaged 1597 yuan/ha) K application on maize in SW and on rice in NW had larger net benefit
Net benefit of vegetables Average of net benefit (1Yuan/ ha) 25 2 15 1 5 Cabbage Lettuce Turnip Chili pepper Vegetables Lotus root Water bamboo Tomato Celery Chili pepper Cabbage Tomato Cabbage Cauliflower Celery Cucumber SW SE NW NC and NE Net profit ranged from 2.3-21.7 thousand yuan/ha, average 8.8 thousand yuan/ha Chili pepper in SW achieved the highest benefit, followed by celery in NC and NE Net benefit from vegetables was mostly higher than cereal crops when K added
Net benefit of fruit trees Average of benefit (1 Yuan/ha) 6 5 4 3 2 1 5.3 Banana 1. 1.2 Papaya Orange.2 Chestnut 1.5 1.6 Grape Apple 5. Kiwi Profits ranged 2-53 thousand yuan/ha, averaged 22 thousand yuan/ha Net benefit from banana in SW and kiwi in NW had the higher income SW SE NW
Net benefit of oil crops 45 4 4,56 3,86 Benefit (Yuan/ha) 35 3 25 2 15 1 5 89 1,146 565 824 1,783 1,493 Rape Rape Peanut Soybean Sesame Sunflower Peanut Soybean SW SE NW NC and NE Profits ranged from 565-456 yuan/ha, averaged 181 yuan/ha Rape in SW and peanut in NC and NE had the higher income
Profitability of tuber crops Average of net benefit (Yuan/ ha) 8 7 6 5 4 3 2 1 7,26 4,37 3,572 SW NW SE Potato Sweet potato Profit ranged from 437 to 726 yuan/ha, averaged 4878 yuan/ha Potato in NW got the highest benefit
AEK of cereal crops Average of AEK (kg/kg) 22 2 18 16 14 12 1 8 6 4 2 SW SE NW NC and NE SW SE NW NE NC SW SE SE SE NW NE Wheat Maize Rice AEK for wheat was 6.7~14. kg/kg, averaged 9.4 kg/kg; AEK for rice were 4.6~13.4 kg/kg, averaged 8.3 kg/kg; AEK for maize were 7.~2.3 kg/kg, averaged 13.4 kg/kg, higher than that of wheat and rice. AEK in SW was the highest, spring maize was higher than summer maize.
Changes of AEK in China Crops 1958-19 62 1981-19 83 22-2 7 21-2 1 Wheat ns 2.1 7.3 9.4 Maize 2-4 1.6 9.2 13.4 Rice 2-4 4.9 7.7 8.3
AEK of vegetables Average of AEK (kg/kg) 18 16 14 12 1 8 6 4 2 Cabbage Lettuce Turnip Chili pepper Vegetables Lotus root Water bamboo Tomato Celery Chili pepper Cabbage Tomato Cabbage Cauliflower Celery Cucumber SW SE NW NC and NE AEK of vegetables had a large variation from 19-153 kg/ha, averaged 58 kg/ha AEK of turnip in SW, and tomato, celery, chili pepper and cabbage in NW were higher than vegetables in other regions.
AEK of fruit trees Average of AEK (kg/kg) 25 2 15 1 5 2 Banana 18 1 1 8 1 Papaya Orange Chestnut Grape Apple SW SE NW 19 Kiwi AEK ranged from 1.5-2 kg/kg, averaged 12 kg/kg In SW, banana had higher AEK than papaya In SE, AEK of orange was higher than chestnut In NW, AEK of grape and kiwi were higher than apple
AEK of oil crops Average of AEK (kg/kg) 12 1 8 6 4 2 6 Rape 3 3 3 Rape Peanut Soybean 1 Sesame 6 Sunflower 1 Peanut 7 Soybean SW SE NW NC and NE AEK of oil crop was low. Most of AEK was lower than 6 kg/kg.
AEK of tuber crops Average AEK (kg/kg) 9 8 7 6 5 4 3 2 1 85.6 24. 22.4 SW NW SE Potato Sweet potato AEK of potato in NW achieved up to 85.6 kg/kg, significantly higher than other regions Averaged AEK was 44 kg/kg
Yields of cotton and tea 7 Average yield (kg/kg) 6 5 4 3 2 1 With K Without K SE NW SE Cotton distribution Cotton Tea Yield response to K (kg/ha) 8 7 6 5 4 3 2 1 729 755 187 SE NW SE K application increased yield of cotton by 22.4% and tea by 13.5% Yield responses to K was higher for SE than NW Cotton Tea
Profitability and AEK of cotton and tea Average of net benefit (Yuan/ha) 6 5 4 3 2 1 3,21 3,413 5,421 Net benefit of tea was larger than cotton Cotton and tea and had a very low AEK values SE NW SE Cotton Tea Average of AEK (kg/kg) 3.2 3.2 3.1 3.1 3. 3. 2.9 2.9 2.8 3.1 3.1 2.9 SE NW SE Cotton Tea
Nutrient balance Input: Chemical fertilizers: Organic fertilizers Irrigation water Dry and wet deposition from atmosphere Plant seed Bio-fixation Output Crop removal Nutrient loss Dr. ShuIan Li
IM,SX,NX, GS, QH,XJ Region classification HLJ, JL, LN NE NW SW NC MLYR HB, HN,SD,S X,TJ,BJ SH,JS, ZJ,AH, HB, HN, JX YN, GZ, SC, CQ,TB SE GD,GX,HN,FJ
K balance from history in China 1 tonnes -1-2 -3-4 K balance 1965 1975 1985 1995 2 K balance, -248-5 -6 Source: Jiakang Li, 23
Potassium input for different regions ( 1 4 t) Chemical fer,lizer Human and animal excre,ons NE NC MLYR SW NW SE Subtotal ProporIon (%) 58.7 213.8 268.1 76.7 64.6 181.3 863.2 38% 73.8 155.6 12.5 225.1 146.3 79.4 8.7 35% Straw 25.5 183.1 97.3 47.4 21.8 26.1 41.2 17% Cake manure 1.9 2.6 3.1 1.1 2.5.2 11.4 % Green manure.25 1.2 9.1 5.5 2.4 3.6 22.1 1% DeposiIon 17.8 22 19.9 18 15.9 7.6 11.2 4% IrrigaIon 9.28 24.1 23.4 8.64 14.4 6.79 86.6 4% Seed 1.7 2.5 1.9 1.8 2.4.34 1.6 % Subtotal 188.9 64.9 543.3 384.2 27.3 35.3 2297 1% ProporIon (%) 8% 26% 24% 17% 12% 13% 1% Source: Li and Jin (211)
Potassium input SE 13% NE 8% NW 12% NC 26% Green manure Cake 1% manure 1% Deposition 4% Irrigation 4% Seed % SW 17% MLYR 24% straw 17% Chemical fertilizer 38% Human and animal excretions 35% Source: Li and Jin (211)
Crop K output (1 t) NE NC MLYR SW NW SW Crop uptake 283.7 624.5 534 37.8 27.1 22.2 Loss 2.2.5 17.7 5.3.23 6.3 NW 12% SE 9% NE 13% SW 14% NC 28% MLYR 24% Crop K 2 O uptake Source: Li and Jin (211)
K balance in total input/output 15 1 K balance (1 t) 5-5 -1 NE NC MLYR SW NW SE Subtotal -15 Source: Li and Jin (211)
Kg K 2 O input per ha Inorganic fertilizer application NE NC MLYR SW NW SW 27.2 51.6 6.3 28.8 27.1 15.8 Organic fertilizer 46.9 82.7 51.7 15 72.5 63.8 Deposition 8.2 5.3 4.5 6.8 6.7 4.4 Seed.79.6.43.68 1.2 Irrigation 4.3 5.8 5.3 3.2 6. 4. Subtotal 87.4 146. 122.2 144.5 113.3 178.2 Chemical and organic fertilizers are the main K input
Kg K 2 O output per ha NE NC MLYR SW NW SW Crop uptake 131.2 15.7 12 115.8 113.2 118 Loss 1.1 4 2.1 3.7 SW, 118 NE, 131.2 NW, 113.2 NC, 15.7 SW, 115.8 MLYR, 12
K balance per kg/ha Input Chemical Fertilizer Organic fertilizer NE NC MLYR SW NW SE 27.2 51.6 6.3 28.8 27.1 15.8 46.9 82.7 51.7 15 72.5 63.8 Deposition 8.2 5.3 4.5 6.8 6.7 4.4 Irrigation 4.3 5.8 5.3 3.2 6 4 Seed.79.6.43.68 1.2 Subtotal 87.4 146. 122.2 144.5 113.3 178.2 Output Crop uptake 131.2 15.7 12 115.8 113.2 118 Loss 1.1 4 2.1 3.7 Subtotal 132.2 15.8 124 117.8 113.3 121.7 Balance -45-5 -2 27 57 Source: Li and Jin (211)
K balance per kg/ha 8 6 K balance (kg/ha) 4 2-2 NE NC MLYR SW NW SE Average -4-6 Source: Li and Jin (211)
Summary1: Crop responses to K Crops Yield (t/ha) Yield increase (%) Yield response (kg/ha) Profit (yuan/ha) AE (kg/kg) Cereals 8.1 14 99 1597 1.3 Vegetables 63.2 15 85 88 58 Fruit trees 32.5 23 6 22 12 Oil crops 3. 17 433 181 4.8 Tubers 28.1 18 4 4878 44 Cotton 2.5 22 458 333 3.1 Tea 6.4 14 755 5421 2.9
Summary2: K nutrient balance K input: chemical fertilizer, human and animal excretion, and crop straw K output: crop removal K balance: NE, NC, MLYR (Grain production base): deficit SE, SW: sufficient
Potassium management strategies Efficient use all kinds K resources: organic fertilizers, crop straw (52% of K input, only 1/3 of crop straw returned back soils) Balanced fertilization with N, P and other nutrients K splits (soil texture-sandy soil, right time, right placedeep fertilization) to avoid leaching Other K resources: irrigation water, rainfall Sensitive crops preference: tobacco, banana Application of K under BMP of other practices
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Thank you and comments 211 IPNI China Program Annual Meeting