Polysulphate Cocoa Trial
13.6
Four locations in Ghana 2022
13.6
Key Conclusions
This study reviewed cocoa trials at 4 locations in Ghana and found that Polysulphate significantly increased the two-year cumulative dry cocoa bean yield at 3 of the 4 locations, generating an average increase in dry bean yield of 13.6% compared with the reference granular fertilizer, or 70.8% compared with the unfertilized control. Based on these results, Polysulphate is considered suitable for mature cocoa plantations at the application rate of 375 kg/ha.
Objective
To investigate the effect Polysulphate has on the yield of mature cocoa trees and to compare it with a comparable granular NPK fertilizer which also contains calcium, magnesium, and sulfur.
Trial Details
Trial station
Four locations in Ghana
Crop
Cocoa
Product
Granular Polysulphate
Assessments
Dry cocoa bean yield
Treatments
The study was conducted by the Cocoa Research Institute of Ghana (CRIG) in 2020/21 and 2021/22 cocoa seasons on farms at 4 locations: Assin Nkukuasa (Central Region), Bechem (Ahafo Region), and Konongo and New Edubiase (Ashanti Region). The trial utilized a randomized complete block design, incorporating 3 treatments and 2 replicates per location. The ages of the mixed hybrid cocoa variety trees ranged from 10 to 15 years.
Treatment 1 was the unfertilized control, treatment 2 was the reference granular fertilizer (NPK 0-22-18+9CaO+9MgO+7S) applied at 375 kg/ha per year, treatment 3 was Polysulphate granular fertilizer applied at 375 kg/ha per year. All recommended agronomic practices were followed.
Treatments
The study was conducted by the Cocoa Research Institute of Ghana (CRIG) in 2020/21 and 2021/22 cocoa seasons on farms at 4 locations: Assin Nkukuasa (Central Region), Bechem (Ahafo Region), and Konongo and New Edubiase (Ashanti Region). The trial utilized a randomized complete block design, incorporating 3 treatments and 2 replicates per location. The ages of the mixed hybrid cocoa variety trees ranged from 10 to 15 years.
Treatment 1 was the unfertilized control, treatment 2 was the reference granular fertilizer (NPK 0-22-18+9CaO+9MgO+7S) applied at 375 kg/ha per year, treatment 3 was Polysulphate granular fertilizer applied at 375 kg/ha per year. All recommended agronomic practices were followed.
Results
- Polysulphate significantly increased the two-year cumulative dry cocoa bean yield at 3 of the 4 locations.
- On average, Polysulphate increased the dry bean yield by 13.6% compared with the reference granular fertilizer and by 70.8% compared with the unfertilized control.
- Based on these results, Polysulphate is considered suitable for mature cocoa plantations at the application rate of 375 kg/ha.