Performance of polyhalite as a multi nutrient fertilizer for potato - PowerPoint PPT Presentation

Performance of polyhalite as a multi nutrient fertilizer for potato in Brazil Simone da Costa Mello Crop Science Department- University of São Paulo, Piracicaba, SP, Brazil

Potato Production in Brazil 2016 -Brazilian Institute of Geography and Statistics- (IBGE) Potato Production: 3,851.398 ton Minas Gerais State (MG): 32.7% of total production São Paulo State (SP): 17.3% of total production Paraná State (PR): 21.3% of total production

Study- Potato- Tapira (MG) and Casa Branca (SP) Soil Chemical Analysis of experimental sites Site pH OM P K Ca Mg S g/dm 3 mg/dm 3 mmolc/dm 3 mg/dm 3 Tapira 5.5 37.2 74.1 2.2 28.2 8.9 29.9 Casa Branca 4.9 18.4 4.6 1.1 14.6 4.4 3.6

Potato Varieties Tapira (MG) Asterix variety - Long oval uniform red tubers with yellow flesh. French fries and processed products. Casa Branca (SP) Romeo variety – dark red tubers Fried foods, baked foods and purees.

TREATMENTS K 2 O Blend N P 2 O 5 Ca Mg S rate -----------------------------------------Kg/ha--------------------------------------- 150 526 Blend I 0 0 574 0 326 150 526 75 3750 574 0 326 4-14-2 MOP + Urea + TSP + SSP 150 526 150 3750 574 0 326 4-14-4 MOP + Urea + TSP + SSP 150 526 225 3750 574 0 326 4-14-6 MOP + Urea + TSP + SSP 150 526 300 3750 574 0 326 4-14-8 MOP + Urea + TSP + SSP 150 526 0 0 65 19 102 Blend II 150 526 75 3750 65 19 102 4-14-2 Poly + Urea + MAP 150 526 150 3750 130 39 204 4-14-4 Poly + Urea + MAP 150 526 225 3750 195 58 305 4-14-6 Poly + Urea + MAP 150 526 300 3750 260 78 407 4-14-8 Poly + Urea + MAP 150 526 0 0 65 19 106 Blend III 150 526 75 3750 65 19 106 4-14-2 K 2 SO 4 + Urea + MAP 150 526 150 3750 130 39 213 4-14-2 K 2 SO 4 + Urea + MAP 150 526 225 3750 195 58 319 4-14-2 K 2 SO 4 + Urea + MAP 150 526 300 3750 260 78 426 4-14-2 K 2 SO 4 + Urea + MAP

Fertilization pre-plant

Planting of potato seeds Planting potato seeds: Tapira: September 4 th , 2015 Casa branca: July 28 th , 2016

Evaluated characteristics

Soil sampling Soil sampling for each plot: 0-20 cm Period: pre-plant and after harvest Chemical analysis: pH, EC, K, Ca, Mg and S

Sampling of f leaves Sampling of petioles and leaflets (Young expadend leaves) - Tapira (MG): 36, 63 and 84 days after planting (DAP). - Casa Branca (SP): 26, 40, 57 and 71 DAP - Chemical analysis – N, P, K, Ca, Mg andS

Potato Harvest Harvest: Tapira: January 18 th , 2016 Casa Branca: November 5 th , 2016 Size of tubers: < 28 mm 28-33 mm 33-42 mm 42-70 mm

No commercial yield - Diseases Spongospora subterranea Streptomyces scabies Pectobacterium carotovora supspp . Meloydogyne spp.

No commercial yield - Physiological disturbs Cracks Silking Greening Lenticelose

Potato quality Qualitative characterisits: - Starch - Hardness - Crunchiness - Dry mass - total soluble - reducing sugar - total soluble solids

Results – Tapira (MG)

Soil fertility – K content 4 3.5 3.17a K content (mmolc/dm 3 ) 2.8ab 2.78ab 3 2.5 2.23b 2 1.33c 1.5 1 0.5 0 0 75 150 225 300 kg/ha of K 2 O

Soil fertility – S content 70 59a 60 S content (mg/dm 3 ) 50 41.5b 41.3b 40 30 20 10 0 POLY MOP K2SO4 300 kg/ha of K 2 O

Leaf nutrient - Ca and Mg contents at 36 DAP Interation Source X rates at 36 DAP Interation Source X rates at 36 DAP Ca - Leaflet Mg - petiole 8 POLY K2SO4 MOP POLY K2SO4 MOP Ca conc. in the leaflets (g/kg) 11 Mg conc. in the petioles (g/kg) 10.6a 7.5 10.5 7 6.81a 10 6.5 9.5 9.33b 6 9 8.55b 5.5 8.5 5.15b 5.12b 8 5 300 kg/ha of K 2 O 1 300 kg/ha of K 2 O

Leaf nutrient - Ca and Mg contents at 63 DAP Interation Source X rates - Ca - Leaflet Effects of K sources - Mg - Leaflet POLY K2SO4 MOP Poly K2SO4 MOP 11 6 Ca conc. in the leaflets (g/kg) Mg conc. in the leaflets (g/kg) 10.6a 10.5 5.8 5.72a 10 5.6 5.48b 9.5 9.33b 5.4 9 8.55b 5.2 5.15ab 8.5 8 5 1 300 kg/ha of K 2 O

Nutrient uptakes - tubers 90 K Ca Mg s Nutrient uptake by tubers 75 60 (kg/ha) 45 30 15 0 0 75 150 225 300 Kg/ha K 2 O

Commercial yield Commercial Yield (t/ha) 35 y = 0.0432x + 16.142 R² = 0.9968 30 25 20 15 0 75 150 225 300 Kg/ha K 2 O

Quality potato POLY K2SO4 MOP 20 15.23a 14.31ab 13.56b 15 10 5 1.33a 1.24ab 1.2b 0 Hardness (N) Crunchness (N/mm)

Quality potato – Starch content Interation Source X rates 16 POLY K2SO4 MOP Starch content (g/100g) 15 14.28a 14 13.53a 12.63a 13 12.39ab 12 11.42b 11.19b 11 10 225 300 Kg/ha K 2 O

Quality potato 20 POLY K2SO4 MOP 19 Dry mass (%) 17.96a 18 17.38a 17 16.43a 15.81b 15.78ab 16 15.59b 15 225 300 Kg/ha K 2 O

Results – Casa Branca (SP)

Soil fertility – Ca content 25 19.2a Ca content (mg/dm 3 ) 20 15 12.7 b 9.5c 10 5 0 POLY MOP K2SO4 75 kg/ha of K 2 O

Soil fertility – Ca content 18 15.5 a 14.5 a 15 Ca content (mg/dm 3 ) 12 11.3 b 9 6 3 0 POLY MOP K2SO4 150 kg/ha of K 2 O

Soil fertility – Mg content 8 6.5 a Mg content (mg/dm 3 ) 5.5 ab 6 4.75 b 4 2 0 POLY MOP K2SO4 300 kg/ha of K 2 O

Leaf nutrient – Mg and S contents in the leafl flets Fertilizer Mg content in Mg content in S content in the the leaflet at 26 the leaflet at 40 leaflet at 57 DAT DAT DAT MOP 3.66 b 3.34 b 2.78 b SOP 4.31 a 4.84 a 3.63 a POLY 4.18 a 4.71 a 3.11 a

Total Yield 30 Total yield (t/ha) 27.9 a 27.8 a 28 26 24.3 b 24 POLY MOP K2SO4

Commercial yield 45 Commercial yield t/ha 40 167 kg/ha = 44,51 t/ha 35 y = -0.0005x 2 + 0.1671x + 30.546 30 R² = 0.8929 25 0 75 150 225 300 Rates of K 2 O

Quality potato 21 20.29a Hardness (N) 20 19.14 ab 19 18.53 b 18 MOP SOP POLY

Conclusions a) The effect of polyhalite on commercial yield depends on the soil fertility, considering K, Ca, Mg and S as source of nutrients: The K rates improved the potato commercial yield at Tapira (MG). The amount of 167 kg K 2 O ha -1 improved the potato commercial yield at Casa Branca (SP) c) Polyhalite fertilizer improves the important characteristics of potato quality as starch content, hardness and crunchiness.

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