Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
After completing Units in this Lesson, you have learned to answer:
1. What is Striga?2. How striga affects chili crop?3. What cultural methods you practice to control
Striga?4. What chemical methods help in controlling Striga?5. What good husbandry practices you will adopt to
control Striga in chili crop?
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Striga is a very important weed in chili pepper cultivation.
Unlike other weeds, which compete for water and nutrients Striga, as a root parasite, literally sucks the life out of chili pepper plants. In doing so, growth is stunted and yields are greatly reduced.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Striga has been given the common name of "witchweed" because of attaching to the roots and robbing the host of water and nutrients.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
There are different species of Striga.
The Striga found in India is most often has white flowers. But, Striga plants with yellow, pink or purple flowers are also common.
White flowered Striga
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Mauve flowered Striga
Red flowered Striga
Pink flowered Striga
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Small Striga seedscompared to sorghum and maize
Depending upon the extent of infestation, 30-60% of reduction in grain yield can occur.
Striga infestation is most severe in low moisture and low fertility soils.
Thousands of very small seeds are produced by a single plant of Striga. These seeds can remain dormant but viable for many years.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Striga plants emerge from the soil adjacent to chili pepper plants and produce many upright green stems with pink to white flowers.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Flowering can begin within 2 weeks and seeds begin to mature 2-4 weeks later. The seed capsules may contain 400-500 seeds and a single plant may produce 20,000 seeds.
Mature seeds are dispersed by wind, rainwater, cultivation, soil on tools, or even grazing and manure fertilization.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Striga Life-Cycle
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Control measures
Physical control: Hand pulling at too early stage may break the shoot and reduce the rapid growth.
Sparse infestation should be hand pulled shortly before flowering to prevent build up of seed.
Such hand pulling should continue through to harvest and beyond so long as flowering is occurring.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Control measures
Cultural control: It has been noted that chili pepper plant shading can restrict Striga growth when generous soil fertilizer is applied.
In areas of high rainfall, factors such as high plant populations, recommended fertility levels, and good weed control encourage lush crop growth and shading in spite of Striga parasitism. This is not feasible in moisture stressed rainfed areas.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Control measures
Cultural control: Crop rotation should be practiced with trap crops which stimulate Striga seeds to germinate without themselves being parasitized.
Crops claimed to be effective include: cotton, sunflower, groundnut, castor, dolichos bean, and linseed.
Unfortunately once a severe infestation has developed, it may take many years to reduce Striga population in the field to non-damaging level.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Control measures
Chemical control: As Striga is a broadleaf plant, pre-plant herbicides such as Atrazine, Goal, and Flex show some effect though not efficient enough to be justified.
Post-emergence use of 2,4-D is effective when sprayed on the Striga leaves.
Though low in cost, chili pepper is vulnerable to stalk twisting and lodging if 2,4-D is sprayed into the leaf whorl. Spraying should only be done trained labor and cautioned to the hazards.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Control measures
In summary, control of Striga infestation is difficult and requires an integrated approach.
Non-host crops must be rotated (for two years in heavily infested fields) with resistant chili pepper varieties.
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Abutilon indicumIndian mallow
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Alysicarpus sp.One-leaf clover
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Argemone mexicanaMexican poppy
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Celosia argentinaWhite cock's comb
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Borreria articularisButton plant
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Cleome sp.Wild spider flower
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Digera arvensisKundra
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Corchorus olitoriusJew's mallow
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Euphorbia purvifloraEuphorbia hirta
Spurge
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Portulaca oleraceaCommon purslane
Portulaca pilosa
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Vernonia cinereaLittle iron weed
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Leucas asperaDronapushpi
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Xanthium strumariumCocklebur
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Amaranthus spp.Pigweed
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Anagallis arvensisScarlet Pimpernel
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Bidense pilosa Spanish needle
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Mollugo verticillataCarpet-weed
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Commelina spp.Benghal dayflower
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
False daisy
Eclipta albaEclipta prostrata
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Ipomea spp.Morning glory
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Tridax procumbenceTridax daisy, wild daisy
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Chloris barbataSwollen Finger grass
Chloris gayanaFeather Finger grass
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Digitaria sanguinalisCrabgrass
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Dactyloctenium aegyptiumCrowfootgrass
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Echinocloa spp.Barnyard grass
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Paspalum distichum.Water couch
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Eleusine indicaGoose grass
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Eragrostis spp.Lovegrass
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Setaria spp.Foxtail
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Cyperus rotundusPurple nut sedge
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Cyperus compressus Nut sedge
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Cyperus defformis Nut sedge
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Cyperus esculantusYellow nut sedge
Module IX: Weeds and Weed ControlLesson 1: Weeds and Weed Competition in Chili Pepper
Unit 3: Striga
Cynodon dactylonBermuda grass
