Section 8: Production Packages for Growers
Based on the current knowledge from various field trials on research stations and farmers’ fields, the following three packages are recommended for producing quality groundnuts. These provide a low, medium and high input options that farmers can follow depending on the available of resources and market opportunities. These are summarized in Table 8.1 and briefly describe below.
Low Input Package
Some farmers have limited access to inputs or simply do not have financial resources or credit to purchase inputs even if they are available. In this case there are fundamental steps farmers can implement that increase the likelihood that yield will be optimized under a low input system.
First, plant groundnuts in fields that were planted to crops other than groundnut the previous year. This will minimize the impact of some pests including leaf spot disease and nematodes. Second, plant high quality seed (either as saved seed for no more than 3 season or as recently purchased seed) as soon as the rains begin after conducting a germination test using the steps outlined earlier in this guide. This will enable you to establish plants at the correct spacing of 10 cm apart for Spanish types or 15 cm apart for Virginia types. In this package, we are assuming fertilizer and pesticides are not available to promote plant health and protect groundnuts from 36 pest injury. Therefore, every attempt should be made to sow a variety with some degree of resistance to disease and rosette. Plant as early as possible to reduce the likelihood of groundnut rosette and to ensure the crop is mature before soil conditions get hot and dry (which can contribute to higher aflatoxin levels). Farmers should weed fields within the first 3 weeks after planting and follow up with an additional weeding no later than 6 weeks after planting. Digging groundnuts at optimum maturity is important in this production system be sure to determine maturity using the shell-out or hull-scrape method. Digging too early results in lower yield and quality because pods and kernels are immature. Digging too late can result in greater contamination by mold and aflatoxin, poorer kernel quality due to damage from pests and sprouting of seed. The result is much lower yield and poorer quality and marketability. If farmers sort prior to selling in the market, they will have much lower turnout of premium kernels for the market. Farmers should dry groundnuts as quickly as possible and store in a manner than protects groundnuts from mold production and damage from insect and vertebrate pests.
Low Input Package Take-Aways:
• Plant an improved variety of groundnut as early as possible in fields that did not have groundnuts the previous season
• Plant high quality seed with known germination as soon as the rains begin at a spacing of 10 to 15 cm for all varieties (5 to 7.5 cm along the twin or double row)
• Weed fields three and six weeks after planting
• Dig groundnut at optimum maturity or one week prior to optimum maturity if drought has occurred
• Dry groundnuts as quickly as possible
• Store groundnuts in a clean and dry building, off of the floor and away from walls
Medium Input Package
If farmers have access to inputs and resources or credit for purchasing inputs, a few key inputs can be added to the low input package for higher yields and quality. In most cases, these added inputs will deliver economic returns above investment cost, although careful selection of inputs is required. Throughout the season, a farmer using a medium input package should follow all the advice offered in the low-input package: Choose a site that is appropriate for groundnut and a variety with resistance to disease, conduct a germination test so that you can achieve optimum plant spacing, weed twice and at the correct time, harvest groundnuts at optimum maturity, dry as quickly as possible and store in a way that protects groundnuts from mold growth and damage from pests.
The most fundamental input to increase yield potential in the medium input system is applying lime to increase soil pH. When soil pH is established at 6.0, groundnuts have a greater capacity to respond to fertilizers and inoculant that promotes biological nitrogen fixation (BNF). In the medium input system, a general fertilizer with adequate phosphorus and potassium also will increase yield. Many blends of fertilizer contain nitrogen and can boost yield, especially if inoculant for BNF is not available or viability and quality are in question. A fertilizer blend that includes calcium will also increase yield and quality. Gypsum is also a good investment and often ensures proper kernel development and increases yield. If available, inoculant that has been handled well and is viable can also increase yield. An important note of caution on this recommendation is that groundnuts are often nonresponsive to inoculant for BNF and gypsum when pH is less than 5.8. In some cases when soil pH is low applying gypsum further decreases yield. A final input in the medium input system would be a single fungicide application 45 days after planting. This will slow epidemics of leaf spot disease and can protect yield.
Medium Input Package Take-Aways:
• Lime soil to obtain a pH of 6.0
• Plant an improved variety of groundnut as early as possible in fields that did not have groundnuts the previous season
• Apply inoculant for BNF
• Plant high quality seed with known germination as soon as the rains begin at a spacing of 10 cm for Spanish-types and 15 cm for Virginia-types for all varieties.
• Apply phosphorus with potassium fertilizer
• Weed fields three and six weeks after planting
• Apply gypsum at flowering
• Dig groundnut at optimum maturity or one week prior to optimum maturity if drought has occurred
• Dry groundnuts as quickly as possible
• Store groundnuts in a clean and dry building, off of the floor and away from walls
High Input Package
In the high input system farmers should include all recommendations associated with the low and medium input systems. Site selection, proper rotation, selection of high quality seed of an improved variety, establishing optimum plant stands, adjusting pH to 6.0, applying fertilizer including gypsum, applying inoculant for BNF with seed, digging at optimum maturity and drying quickly, and storing in a manner that reduces mold growth and injury from insects and vertebrates form a foundation for the high input system.
The next level of input includes pesticides. In the high input system, farmers should use pre-emergence and post-emergence herbicides to control weeds. Herbicides are more efficient than hand-weeding and often damage groundnuts less than removing weeds by hand. Farmers should also scout for insect pests, check to see if the number of pests surpass thresholds and, when possible, apply insecticides. In the high input system, farmers should apply fungicides 3 times during season beginning 30 days after planting with the second spray made 45 days after planting and the final spray 60 days after planting. It is important to use only those pesticides that are registered for use by the manufacturer for groundnuts grown in Malawi. Proper equipment should be used to deliver pesticides and those making pesticide applications must wear approved personal protection equipment and clothing to prevent injury. Fields should be marked so that people and livestock do not enter for the appropriate period of time outlined on the pesticide label and all applications should adhere to preharvest intervals that are provide by the manufacturer.
High Input Package Take-Aways:
• Lime soil to obtain a pH of 6.0
• Apply inoculant for BNF
• Plant an improved variety of groundnut as early as possible in fields that did not have groundnuts the previous season
• Plant high quality seed with known germination as soon as the rains begin at a spacing of 10 to 15 cm for all varieties (5 to 7.5 cm along the twin/double row)
• Apply herbicide with residual activity immediately after sowing and include glyphosate if weeds have emerged when sowing is complete. • Apply phosphorus with potassium fertilizer • Weed fields three and six weeks after planting
• Apply herbicide that controls emerged weeds three weeks after planting
• Apply fungicide 30, 45 and 60 days after planting to protect groundnuts from pathogens that cause leaf spot disease and rust.
• Apply gypsum at flowering
• Dig groundnut at optimum maturity or one week prior to optimum maturity if drought has occurred
• Dry groundnuts as quickly as possible
• Store groundnuts in a clean and dry building, off of the floor and away from walls
