· Using a peg-toothed harrow, cultivate or off bar 10-15 days after emergence to control weeds.
· If needed, hill up at 25-30 days after emergence to ensure easier penetration of pegs into soil and proper formation of pods particularly in clay soil. However, hilling up may promote build up of Sclerotium roltisii which causes stem rot disease and sprouting of early developed pods.
· Avoid cultivating at the peak flowering and pegging stages to prevent abortion of first open flowers and disturbance of pod formation.
· Moisture is a limiting factor for production. Water is most critical at planting or immediately after planting, and during the vegetative, flowering, pegging, seed formation, and pod setting stages.
· If possible, irrigate dry soils before or just after planting to ensure good crop emergence.
· Irrigate lightly but frequently at pegging to pod development stages.
· Besides increasing yield, the absence of soil moisture at pod and seed development stages will also encourage seed and pod invasion by Aspergillus flavus.
· Topsoil must remain moist at pegging stage to facilitate penetration of pegs into the soil.
· In the absence of rainfall, sprinkler irrigation is the most efficient method.
How to Protect the Crop from Major Pests?
· Weeds reduce peanut yield through competition and often harbor insect pests and diseases.
· Weed control is more critical in peanut production than in other crops because peanut grows slowly and cannot compete well with weeds during the greater part of its growth cycle. Weeds, therefore, should be controlled during the first 4-8 weeks after planting.
· Rottboellia cochinchinensis (Lour.) W. D. Clayton is the most troublesome weed associated with peanut. It is also the most difficult to control. This weed produces approximately 5,000 viable seeds plant per year. It remains viable for a year or longer, resulting in flushes of germination. It is highly competitive because it grows taller and more vigorous than peanut.
· Other weed species that can suppress peanut growth are the grass Eleusine indica L. (asparagus “sabung-sabungan”, ”bangangan”, ”dinapulok ”, “bakis-bakisan”/”bikad-bikad”, “patagkiti”, dog’s tail) ,the sedge Cyperus rotundus L. (“boto-botones”, “muth’a”, “malapulid”, “sur-sur” and “malapndang”), and the broadleaf Ipomoea triloba L. (“kamo-kamotehan” and “baging”).
· To control such weeds, use appropriate pre- and post-emergence herbicides.
Various yield-reducing insect species attack peanut at different growth stages. These include bean fly, cutworms, leafhopper, bean aphids, corn earworm, corm semi-looper, white grub, leaf folder, leaf miner, tiger moth, caterpillar and earwig. Pods and roots are infested by termites, ants, and root feeding grubs.
Practice integrated pest management control strategies through thorough land preparation, use of resistant varieties, intercropping peanut with corn or sorghum (as trap crop), clean fields, preservation of friendly insects as natural enemies, and need-base spraying of insecticides. Use contact insecticides ion controlling persistent leaf-feeding insects and spray early in the morning (5:00-7:00 a.m.) and late in the afternoon (4:00-6:00 p.m.).
· Major diseases are Cercospora leaf spot (CLS), peanut rust, peanut stripe virus (PStV), bacterial and fusarium wilt, and leaf rust.
· If fungus/foliar diseases infect the plants at early growth stages (pegging to pod-filling stage), spray appropriate fungicides.
· Uproot or rogue virus-infected plants and wilted plants due to bacterial wilt then burn to prevent spread of diseases.
· Soil and seed-born disease like bacterial wilt attacks the plants from seedling to maturity stage; remove/uproot, infected plants then burn.
What Harvest and Postharvest Operations Must be Done?
· Generally, all recommended varieties in the region mature in 90 and 100 days emergence during the dry and wet season, respectively.
· Recently introduced confectionery varieties (large-seeded) like NSIC Pn 11, 12, and 14 mature from 110-140 days after emergence depending on cropping season.
· In loose soils, harvest the crop by uprooting or hand pulling the plants.
· Plow between furrows before uprooting or use spading fork to ease uprooting in heavy/clay soils.
· Physiologically matured plants shows pods with 70-80% prominent veins, the inner portion of the shell turns dark, and the testa (seed coat) has the normal color of the genotype.
· During dry season wherein the crop is usually harvested towards summer months (March-April) withdraw the uprooted plants in the field for 2-3 days to partially dry the pods before stripping (separation of pods from the plants). However, to avoid mold growth particularly during wet season, it is recommended that stripping be done immediately after uprooting. Stripping may be done manually or with the use of a mechanical peanut stripper.
Drying seeds after harvesting
a. For Selling as Commercial Seed
· The moisture content (MC) of newly harvested pods usually ranges from 35% to 60%.
· Dry the pods (Stripped pods just after hand pulling in the field) for 2-3 days full sunlight to attain MC of 12-15% before selling or storing.
· Sundry/Re-dry for another one sunny day the pods of windrowed plants in the field (2-3 days windrowed).
· Place the pods in the jute sack and pile them in a well ventilated place to lessen the adverse effect of humidity and temperature.
b. For Storage as Planting Materials
· Dry the pods intended for seeds gradually to about 8-10% MC.
· To attain the right MC, dry windrowed pods for 2-3 days and newly harvested/ stripped pods for 4-5 days.
· Spread the pods uniformly on the sun drying surface to a thickness of 1-2 layers and turn pods manually once (12:00 noon) or twice (11:00a.m. and 3:00 p.m.)
· If the seed coat ruptures and separates from the cotyledon, the MC is approximately 8-10%.
· Select only sound, mature, clean and well-filled pods for use as seed.
Safe seed storage
Peanut stores better in pods than in seeds and it loses quickly its viability if stored improperly. Generally, the lower the temperature, the longer the expected storage life of the stored seeds. Temperature below 13 degrees Celsius inactivates growth of most storage pests. The relative humidity (RH) should be between 65% and 70% because mold growth is encouraged at higher RH levels. At RH below 65%, peanut pods lose weight and seeds become brittle and split during handling.
Seed storage procedures
Properly dried pods can be stored in cold storage ‘bodega’ or in storage container or drum designed by the Bureau of Post Harvest Research and Extension and improved/promoted by the Department of Agriculture-Cagayan Valley Low Land and Marine Research and Outreach Station. In the absence of expensive cold storage, storage drum can be used to preserve seed viability for 6-8 months under ambient temperature. The following procedures must be strictly done to ensure safe storage in drums:
· After last sun drying, temper or cool dried peanuts for 6-12 hours or overnight. Peanuts stored when still hot will cause sweating and increases moisture content.
· Fill the storage container with 150 kg of unshelled peanuts (small to medium sized seeds).
· Close the container tightly and leave undisturbed to prevent the entrance of air and moisture.
· Place seed storage container inside the house or warehouse to protect them from rains and floods.
· Open the storage container 3-5 days before planting.
An effective marketing scheme is vital to profitable peanut farming. Peanut growers usually sell the bulk of their produce unshelled to middlemen and retailers. To get better prices, shell and pre-grade the produce before selling directly to peanut processors.
In Cagayan Valley, local peanut buyers usually haul the properly dried pods from the farm or from the drying area. Regardless of variety and seed size, buying price ranges from P25 to P28/kg (pick-up price). If major processors from Metro Manila will buy the seeds, it should be in shelled and pre-graded form priced ad P50-P60/kg with a minimum volume of 10-20 t/hauling. Other local buyers in Tuguegarao City, Cagayan, Iligan, Cauayan, Roxas, Echague and Santiago City, Isabela accept cash on delivery scheme.
Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD)
Department of Science and Technology (DOST)
Cagayan Valley Agriculture and Resources Research and Development Consortium (CVARRD)
Isabela State University (ISU)