2018–19 summer: Kairi peanuts in red scrub soil, Kingaroy
Grower: Greg Birch grows peanuts, corn and sorghum, mungbeans and manages some cattle.
Monitored area: 28 ha, in red scrub soil
- Fertiliser applied was via strip till application with a mixture of CK 55 and Calciprill (lime granule).
- Paddock was sprayed prior to planting with glyphosate (Roundup) and 2,4-D.
- Established a plant population of 80,000 plants/ha in mid-December
- 91 cm (3’) row spacing
- Metolachlor (Clincher Gold) was applied post-plant pre-emergent for grass and broadleaf weed control.
- A herbicide tank mix of Impose, Ardeo and Butress was applied to control the range of weeds present including nutgrass, melons, star burr, cobblers pegs, thornapple and wild radish.
Peanut mites have been found widespread in this peanut paddock due to the prolonged dry conditions. Monitor your peanut paddocks closely.
- An outbreak of peanut mites was found in distinct patches across this peanut paddock. Damage was selective but severe where the plant leaves appeared a yellowish, white colour. Peanut mites appear infrequently most seasons, during periods of hot dry weather, but damage is usually minimal. The mites usually disappear after rainfall and the plants outgrow the damage. Plant death can occur if left uncontrolled and the hot dry period continues.
- As there was no rain forecast, and the damage was widespread and severe, it was recommended to spray the crop.
- The insecticide controlled the mites and the crop will continue to be monitored.
- The insecticide for mite control (dimethoate) has worked well, with the affected plants recovering well.
- Patches where the peanuts were affected can still be seen, however not as distinct as it was when first discovered.
- Peanut paddocks should still be monitored for mites; though it is getting harder to see the mite affected patches now as the peanuts are wilting due to the dry and all look silver during the day. Closer inspection should demonstrate whether it is mite damage or moisture stress.
The insecticide applied last week for mite control (dimethoate) has worked well, with the affected plants recovering well.
- Peanuts are looking healthy despite the prolonged dry weather.
- The crop is flowering and starting to develop pegs.
- A question often asked with peanuts is the detection of leaf diseases early on in the season. It is common for herbicides used to spray broadleaf weeds to cause a phytotoxicity effect (leaf burn) on the peanuts leaves, which can be mistaken for leaf spot or another leaf disease. Diagnosis can be difficult so consult your local agronomist.
Leaf burn from herbicide damage can look like leaf spot.
- Peanuts received 10 mm of rainfall this week.
- Good root development.
- Crop continues flowering well and plants are healthy.
Good root development to support the crop through flowering and podding.
- The peanut plants are continuing to develop and are looking healthy and green despite the dry.
- Flowering is continuing and pegs are developing. Decent rainfall is required very soon to ensure continued plant growth, flowering and pod development.
- Peanuts are very drought hardy, with the ability to “sit and do nothing” through extended dry periods. If decent rainfall occurs the crop will then develop as normal and good yields can still be achieved. However they are frost sensitive and so rainfall needs to occur soon to allow the crop to mature before the first frost event.
- Total of 10 mL of rainfall was received this week.
- No insect or disease concerns at this stage.
Pegging has started as this crop waits for rain.