A forewarning calendar answers one question: what is coming, and when do I have to act? Every disease and pest on this page has a season in which it peaks, and every control measure below has to be applied before that peak rather than during it. Spraying after the leaf spot is visible saves very little; the same spray two weeks earlier controls most of it. The calendars set the dates; the measures set the doses.
Forewarning calendar — som diseases
Leaf spot, anthracnose and grey blight on Persea bombycina (som), month by month.
Control measures
Leaf spot disease
- Cultural
- Regular cultural operations, pruning and pollarding prevent the disease.
- Chemical
- 0.1 % Dithane M-45 (1 g / 1 litre), twice at a 15-day interval before the peak season of incidence. Controls the disease up to 96 %.
Anthracnose of som
- Mechanical
- Pluck the infected parts and destroy them by burning; this destroys the pathogen rather than moving it elsewhere in the plantation.
- Chemical
- 0.1 % Bavistin (1 g / 1 litre), twice at a 15-day interval before the peak season of incidence. Controls the disease up to 96 %.
Grey blight disease
- Cultural
- Timely cultural operation, pruning and pollarding can prevent the disease.
- Chemical
- Foliar spray of Bavistin, twice at a 15-day interval. Checks the disease up to 85.2 %.
Forewarning calendar — muga host plant pest, stem borer
Control measures
Stem borer
- Plant extracts
- 5–15 % plant extract of neem, dhatura, titabahak or castor controls the infestation.
- Chemical
- Plug the borer holes with a cotton swab soaked in 1.5 % Nuvan, then plaster the openings with mud. The plaster matters as much as the swab — it holds the vapour in the tunnel.
Leaf gall
- Cultural
- Collect the infested leaves and twigs and destroy them in a scientific way.
- If infestation is heavy
- Above 25 % infestation, pruning and burning of the leaves and twigs is essential — collection alone will not hold it.
Forewarning calendar — silkworm disease
Muscardine and flacherie across the muga crop year. Jarua, the December–January pre-seed crop, is the crop most exposed to muscardine.
Control measures
Muscardine
- Site
- Select a sunny plot for rearing.
- Cultural
- Disinfect the rearing field properly. Use of nylon net is essential.
- Prophylactic spray
- Spray LAHDOI thoroughly on the leaves, tree trunk and soil seven days before brushing of the Jarua crop. After brushing is too late.
Flacherie
- Cultural
- Disinfect the rearing field properly.
- Leaf management
- Follow the proper pruning schedule and provide age-specific leaves. Flacherie in muga follows unsuitable leaf as often as it follows infection.
Forewarning calendar — uzi fly
The uzi fly (Exorista spp.) is a parasitoid, not a pathogen: it lays on the larva and the maggot emerges from the mature worm or the cocoon. Forewarning matters here because the only effective response — netting and trapping — has to be in place before the fly population builds.
Host families, seasonal build-up and the standing community of parasitoids and predators are described on Insect Pests & Predators.
Calendars to download
District-wise and quarter-wise calendars issued by the institute.
- Revised Forewarning Calendar 2016 — host plants and silkworm Consolidated calendar, all districts — not yet published on this site
- Updated disease calendar for muga silkworm and host plants, 2015-16 Districtwise — not yet published on this site
- Disease calendar for the quarter ending September 2014 Quarterly bulletin — not yet published on this site