Rajma pests and their Management

Rajmash: Diseases and Symptoms Anthracnose Rust Root rot Bean common mosaic disease Watery Soft Rot Angular leaf spot IPM for ...

Rajmash: Diseases and Symptoms

1. Anthracnose
2. Rust
3. Root rot
4. Bean common mosaic disease
5. Watery Soft Rot
6. Angular leaf spot
7. IPM for Rajmash

Anthracnose

Disease symptoms:

• Symptoms of anthracnose can appear on any plant part. Pale brown sunken spots may appear on the cotyledons of infected seedlings.Spots may spread to the hypocotyle, which if girdled, kill the seedlings. Lesions on leaves are dark brown.
• They are restricted to the veins on lower leaf surface. On stems, lesions are elongated and sunken.
• On the pods, the fungus produces black, sunken lesions. These lesions penetrate deep into the pods and may cause shrivelling of the young pods.
• Infected seed become discoloured changing to yellow through brown to black. In damp weather, the centres of anthracnose lesions become covered with a pink spore mass.

Survival and spread:

• The disease is seed-borne and pathogen can also survive in soil. Secondary disease cycles continue until the weather remains favorable.

Favourable condition:

• Frequent showers, heavy dews, temperatures of 20 -30oC, and overcrowding of plants favor the spread and development of anthracnose.

Rust

Disease symptoms:

• Rust-colored pustules form on the lower leaf surfaces.
• Severely infected leaves turn yellow, wilt, and then drop off of the plant.
• Stems and pods may also be infected. It affects most types of beans under humid conditions.

Survival and spread:

• The fungus survives mainly in alternate host.

Favourable conditions:

• Rust progresses most rapidly in susceptible hybrids or varieties when the temperature is near 27oC with high humidity and frequent dews.

Root rot

Disease symptoms:

• Many fungi, including Rhizoctonia solani, Pythium spp., Fusarium solani, Macrophomina phaseolina, survive in the soil and infect young seedlings or the seeds of bean plants.
• Seedlings fail to emerge after planting when the seeds rot in the soil or young seedlings may be stunted.
• Plants are usually affected slightly above or below the soil line with a watery soft rot. Leaves turn yellow and roots get rotten.

Survival and spread:

• Causal organisms survive in soil and seed as resting mycelia or sclerotia for long period. These organisms often survive as saprophytes, living on dead plant material, or as dormant mycelia or spores. Root exudates from germinating seedlings or growing roots stimulate the dormant fungi to become active.

Favourable conditions:

• Diseases are prevalent under cool wet conditions that keep the soil temperatures below 13°C.
• Rhizoctonia root rot is most damaging when cool, wet conditions in the spring are followed by hot (25 -29°C), dry conditions.

Bean common mosaic disease

Disease symptoms:

• Symptoms of bean common mosaic virus (BCMV) are cupping and twisting of leaves with a light and dark green mosaic pattern.
• The dark green tissue is often bubbled and/or in bands next to the veins. Affected plants produce smaller, curled pods with a greasy appearance resulting in poor yields

Transmission and fabourable conditions:

• The virus is seed borne and can also be transmitted by several aphid species

Watery Soft Rot

Disease symptoms:

• Small, soft, watery spots that are caused by the fungus Sclerotinia sclerotiorum occur on the stems, leaves and pods of beans.
• These spots enlarge rapidly under cool, moist conditions and girdle the stem.
• Infected areas of pods become soft, watery and covered by a white fungal growth.

Survival and spread:

• The fungus is soil-borne and infects lower parts of bean plants first. The most important survival mechanism of S. sclerotiorum is the formation of sclerotia. Infection is initially localized and spread rapidly in low lying moist and cool areas under furrow irrigation Favourable conditions:
• Wet and cold weather conditions towards the end of growing season are conducive to white mould epidemics.

Angular leaf spot

Disease symptoms:

• Symptoms consist of small dark brown spots with angular edges and are often numerous to give the foliage a checker-board appearance.
• The spots may increase in size, join together, and cause yellowing and necrosis of the affected leaves. This may lead to premature defoliation.

Survival and spread:

• The disease is seed-borne.

Favourable conditions:

• The disease is favoured by high moisture and moderate temperatures (20-25°C).

IPM for Rajmash

To know the IPM practices for Rajmash, click here.

Source: NIPHM and Directorate of Plant Protection, Quarantine & Storage

Rajmash Pests

1. Pests of National Significance
1. Insect pests
2. Diseases
3. Weeds
4. Nematode
5. Rodent
2. Pest of Regional Significance
1. Insect pests
2. Diseases
3. Nematodes
4. Weeds
3. IPM for Rajmash

Pests of National Significance

Insect pests

• Aphid: Aphis craccivora Koch (Hemiptera: Aphididae)
• Leaf miner: Melanagromyza trifolii Burgess (Diptera: Agromyzidae)
• Pod borer: Helicoverpa armigera Hubner (Lepidoptera: Noctuidae)

Diseases

• Mosaic disease: Bean common mosaic virus
• Root rots: Rhizoctonia and Fusarium species
• Anthracnose: Colletotrichum lindemuthianum Sacc. & Magnus
• Water softy rot/Stem rot: Sclerotinia sclerotiorum Lib. De Bary

Weeds

Grasses

• Rabbit/crow foot grass: Dactyloctenium aegyptium (L.) Wild (Poaceae)
• Burmuda grass: Cynodon dactylon L. (Poaceae)
• Barnyard grass: Echinochloa crusgalli (L.) Beauv. (Poaceae)

Broad leaf

• False daisy: Eclipta alba (L.) Hassk. (Asteraceae)
• Asthma herb: Euphorbia hirta L. (Euphorbiaceae)
• Scarlet pimpernel: Anagallis arvensis L. (Primulaceae)
• Sweet clover: Melilotus indica (L.) All. (Fabaceae)
• Carrot grass: Parthenium hysterophorus L. (Asteraceae)
• Lambsquarters: Chenopodium album Linn. (Chenopodiaceae)

Sedges

• Purple nut sedge: Cyperus rotundus Linn. (Cyperaceae)

Nematode

• Root-knot Nematode: Meloidogyne spp.

Rodent

• Smaller bandicoot

Pest of Regional Significance

Insect pests

• Stem fly: Ophiomyia phaseoli Tryon (Diptera: Agromyzidae)
• Blister beetle: Mylabris macilenta Marseul (Coleoptera: Meloidae)
• Stem boring weevil, Cypricerces marginatus F (Ostracoda: Cyprididae)
• Flower beetle, Popillia cyanea Hope (Coleoptera: Scarabaeidae)

Diseases

• Rust: Uromyces appendiculatus Pers.
• Angular leaf spot: Phaeoisariopsis griseola (Sacc.) Ferr.

Nematodes

• Lesion nematode: Pratylenchus sp.

Weeds

Grasses

• Crab grass: Digitaria sanguinalis (L.) Scop (Poaceae)
• Canary grass: Phalaris minor Retz. (Poaceae)

Broadleaves

• Pig weed: Amaranthus viridis L. (Amaranthaceae)
• Common purslane: Portulaca oleracea L. (Portulacaceae)
• False amaranth: Digera arvensis Forsk. (Amaranthaceae)
• Goat weed: Ageratum conyzoides L. (Asteraceae)

Sedges

• Flat sedge: Cyperus iria L. (Cyperaceae)
• Yellow sedge: Cyperus esculentus L.(Cyperaceae)

IPM for Rajmash

To know the IPM practices for Rajmash, click here.

Source: NIPHM and Directorate of Plant Protection, Quarantine & Storage

 

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125 ratings

Rajmash: Insect and Mite Management

1. Leaf miner
2. Gram pod borer
3. Aphids
4. Stem fly
5. Root knot Nematode
6. IPM for Rajmash

Leaf miner

Biology:

• Egg: Eggs are minute in size and orange yellow in colour. The egg hatches in 4 days.
• Maggot: Apodous maggot feeds on chlorophyll mining in between epidermal layers. Full grown maggot measures 3 mm and duration is about 7 days.
• Pupa: Pupation takes place inside a thin loose mesh of silken cocoon either in soil or in leaves. Pupal period is about 7 days.
• Adult: It is a pale yellowish fly, measuring 1.5 mm in length. The female fly punctures upper surface of leaf to lay eggs singly. Total life cycle is completed in 3 weeks.

Damage symptoms:

• Leaves with serpentine mines
• Dropping and drying of leaves in severe cases

Favourable conditions:

• Warm weather conditions are favourable for multiplication.

Natural enemies of leaf miner:

• Parasitoids: Gronotoma micromorpha, Diglyphus sp, Halticoptera circulus and Opius sp, Chrysocharis sp, Neochrysocharis formosa (Westwood) etc.
• Predator: Lacewings etc.

Gram pod borer

Biology:

It is a Polyphagous pest, infesting gram, lablab, safflower, chillies, groundnut, tobacco, cotton etc.

• Egg: Ovall, sculptured, yellowish eggs are laid singly on tender plant parts and buds. The egg period lasts for 2-4 days.
• Larva: Caterpillars are of varying colour, initially brown and later turn greenish with darker broken lines along the side of the body. Body covered with radiating hairs. When full grown, they measure 3.7 to 5 cm in length. The larval period lasts for 18-25 days.
• Pupa: Pupation takes place inside the soil in an earthen cell. Pupal stage lasts for 7-15 days.
• Adult: Moth is stout, medium sized with brownish/greyish forewings with a dark cross band near outer margin and dark spots near costal margins, with a wing span of 3.7cm.

Damage symptoms:

• Early instar larvae scrap the chlorophyll of the leaves
• Mature larvae head bore inside the pods and the rest of the body remain hanging out.
• Pods with irregular big holes

Natural enemies of gram pod borer:

• Parasitoids: Carcelia sp., Campoletis chlorideae, Ichneumon promissorius etc.
• Predators: Chrysoperla zastrowi sillemi, coccinellids, King crow, braconid wasps, dragonfly, spider, robber fly, reduviid bug, preying mantid, and red ants etc.

Aphids

Biology:

• Eggs: Eggs are very tiny, shiny-black, and are found in the crevices of bud and stems, of the plant. Aphids usually do not lay eggs in warmer parts of the world.
• Nymphs: Nymph (immature stages) are young aphids, they look like the wingless adults but are smaller. They become adults within 7 to 10 days. Viviparity is also observed
• Adults: Adults are small, back to dark brownish colour, 1 to 4 mm long, soft-bodied insects with two long antennae that resemble horns. Most aphids have two short cornicles (horns) towards the rear of the body.

Damage symptoms:

• Nymphs and adult aphids suck plant sap from leaves, shoots, buds and floret.
• In addition, plants may become contaminated by honeydew produced by aphids and sooty mould growing on honeydew.
• Rajmash contaminated with honeydew and / or sooty moulds are not marketable.
• Aphids are also vectors of diseases, including the common bean mosaic virus.
• The black bean aphid is a widely distributed pest of beans. The black legume aphid usually attacks beans grown at low altitudes

Natural enemies of aphid:

• Parasitoids: Aphidius colemani, Aphelinus sp
• Predators: Fire ant, Robber flies, Big-eyed bug (Geocoris sp), Earwig, Ground beetle, Cecidomyiid fly, Dragon fly, Preying mantid, Lacewing, Ladybird beetle, Spider, syrphid fly etc.

Stem fly

Biology:

• Eggs: The stem fly inserts eggs on the underside of young leaves. Ovipositing sites show pale pinprick spots when infested leaves are held against the light.
• Maggot: Whitish, torpedo-shaped maggots measures about 2mm.and they pupate after 8-11 days inside the stem. Before pupation, the maggot makes an exit hole for the emergence of the adult.
• Pupae: Pupae are smooth, light brown to pale brown, cylindrical in shape with rounded ends. Pupal stage lasts for 6–12 days.
• Adults: Adult flies are shiny black and about 2mm long with a pair of clear wings with a wingspan of 4-5 mm.

Damage symptoms:

• Infested stems are often red inside (sometimes pale) and a distinct zig-zag tunnel may be observed — with maggots or pupae inside. Apart from the exit holes, the plants will initially appear healthy on the outside.
• Heavy infestations (3 or more maggots per plant) may cause wilting and even death of the plant, especially in younger one particularly if damage occurs in the plant’s hypocotyle (basal stem) region.

Natural enemies of stem fly:

• Parasitoid: Tiny wasps

Root knot Nematode

Biology:

• Most species of plant parasitic nematodes have a relatively simple life cycle consisting of the egg, four larval stages and the adult, male and female.
• Development of the first stage larvae occurs within the egg where the first moult occurs. Second stage larvae hatch from eggs and infest plant roots or in some cases foliar

Damage symptoms:

• Infested plants appear in patches in the field
• Formation of galls on host root system is the primary symptom
• Roots branch profusely starting from the gall tissue causing a ‘beard root’ symptom
• Infected roots become knobby and knotty
• In severely infested plants the root system is reduced and the rootlets are almost completely absent hampering their function of uptake and transport of water and nutrients.
• Plants wilt during the hot part of day, especially under dry conditions and are often stunted.
• Nematode infestation predisposes plants to fungal and bacterial root pathogens.

Survival and spread:

• Primary: Egg masses in infested plant debris and soil or collateral and other hosts like Solonaceous, Malvaceous and Leguminaceous plants act as sources of inoculums.
• Secondary: Autonomous second stage juveniles that may also be water dispersed.

Favourable conditions: Loamy light soils.

IPM for Rajmash

To know the IPM practices for Rajmash, click here.

Source: NIPHM and Directorate of Plant Protection, Quarantine & Storage

 

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135 ratings

Rajmash: Crop Stage-wise IPM

1. Pre-sowing*
2. Sowing*
3. Vegetative
4. Flowering/Pod stage
5. Post harvest
6. Rodent management

Stage wise Management	Activity
Pre-sowing*
	Common cultural practices: · Deep ploughing of fields during summer to control nematodes population, to expose pupae;propagules of soil borne pathogens and to reduce the weeds infestation.. · Soil solarization · Timely sowing should be done. · Field sanitation, rogueing. · Destroy the alternate host plants · Growing pea or marigold as a trap crop for the management of Leaf miner. · Plant tall border crops like mustard for the management of aphids. · Crop rotation with non leguminous crops especially cereals. · Adopt ecological engineering by growing the recommended attractant, repellent, and trap crops around the field bunds.ommon cultural practices:
Nutrients	· Fertilizers should be applied on the basis of soil test values and recommendations for particular agro-ecological regions. · Apply 4-5 tons of farmyard manure or vermicompost @1.5-2 t/acre at the time of last cultivation and incorporate in the soil 2 to 3 weeks before sowing. · Incubate Trichoderma @ 500g in 100 Kg FYM for 15 days prior to its application in one acre field
Weeds	· At the time of field preparation, adopt stale seed bed technique i.e. pre sowing irrigation followed by shallow tillage to minimize the weeds menace in field.
Root rot, Stem rot, Nematode, Pod borer	· Application of FYM/Neem or Mahua cake @ 200 Kg/acre. · Seed treatment with Trichoderma @ 5 g/Kg seed
Sowing*
Nutrients	· Seed treatment should be done with Rhizobium cultures @5-10 g/Kg seed. · French bean needs liberal N fertilization (40-45 Kg/acre) because of poor nodulation. The crop requires 25 Kg P2O5/acre. If K status in soil is marginal also apply 10-15 Kg K2O/acre · In sulphur and zinc deficient areas, apply sulphur and zinc sulphate each @ 10 Kg/ acre in soil at the time of sowing.
Weeds	· Always use certified and weed free seeds. · Line sowing should be done to facilitate inter-culture operations. · Plant population should be maintained to its optimum right from its beginning to minimize the crop- weed competition. · Intercropping with crops like maize in kharif and mustard in rabi
Root rots, ematodes, Stem fly, Anthracnose, BCMV	Cultural control: · Select healthy and disease free seeds. · The seeds should be thoroughly rinsed and dried in shade. · Mulching with straw/pine needles/eucalyptus leaves. · Avoid dense sowing. · Sowing in well drained soil. · Follow optimum sowing depth of 5-7 cm. · Intercropping with mustard where nematodes are the problem.
*Application of Trichoderma harzianum/ viride and Pseudomonas fluorescens for treatment of seed/seedling/planting materials in the nurseries and field application (if commercial products are used, check for label claim. However, biopesticides produced by farmers for own consumption in their fields, registration is not required).
Vegetative
	Common cultural practices: · Provide irrigation at critical stages of the crop · Avoid water stress and water stagnation conditions. · Enhance parasitic activity by avoiding chemical spray, when larval parasitoids are observed Common mechanical practices: · Collection and destruction of eggs, and larvae · Collect and destroy diseased infected and insect infested plant parts · Use yellow sticky traps for aphids and leaf miner @ 4-5 traps/acre. · Use light trap @ 1/acre and operate between 6 pm and 10 pm · Install pheromone traps @ 4-5/acre for monitoring adult moths activity (replace the lures with fresh lures after every 2-3 weeks) · Erecting of bird perches @ 20/acre for encouraging predatory birds such as King crow, common mynah etc. · Set up bonfire during evening hours at 7-8 pm Common biological practices: · Conserve natural enemies through ecological engineering · Augmentative release of natural enemies.
Nutrients	· Correct micronutrient deficiency if any in standing crop.
Weeds	· Rajmash suffers severe competition from weeds in initial stages. First 30-40 days after sowing is the critical period for crop- weed competition. Hand tool weeding at 20 & 40 days after sowing should be done for the management of weeds.
Aphids	Cultural control: · Reflective mulches such as silver colored plastic can deter aphids from feeding on plants. · Sturdy plants can be sprayed with a strong jet of water to knock aphids from leaves Biological control: · See common biological practices. · Insecticidal soaps or oils such as neem or canola oil are usually the best method of control; always check the labels of the products for specific usage guidelines prior to use.
Leaf miner	· See common cultural and biological practices.
Mosaic	Cultural control: · Control the vector by adopting common practices for the aphid. Mechanical practices: · All the infected plants should be removed carefully from the field and destroyed.
Angular leaf spot**, Anthracnose and rust**	Cultural control: · Balance use of manures and fertilizers. · Mulching with pine needles or eucalyptus leaves reduces the angular leaf spot.
Flowering/Pod stage
Nutrients	· Incorporate crop residues in soil immediately after harvest.
Weeds	· Remove left over weeds before shedding of seeds to prevent weed seed spread in the subsequent year.
Pod borer	· See common cultural practices. Biological control: · Inundative release T. pretiosum @ 40,000/acre 4-5 times from flower initiation stage at weekly intervals. · Apply entomopathogenic nematodes (EPNs) Steinernema feltiae @ 8 billion infective juveniles/acre.
Stem fly**, Blister beetle**, Stem boring weevil**, Flower beetle**	· See common cultural practices. · Collect the beetle and kill them.
Aphid, leaf miner	· Same as vegetative stage.
Angular leaf spot**, Anthracnose and rust**	· Same as vegetative stage.
Post harvest
Seed borne fungi, Rust**, White rot, Anthracnose	· Collect crop residue from the field after crop harvest and burn them. · Clean the seeds properly, remove broken or shriveled grains. · Dry the seeds properly and store in air tight seed bins.
Rodent management
Smaller bandicoot	Cultural control: · Practice clean cultivation/maintain weed free fields which reduces the harboring/hiding points for rodents. · Practice trapping with locally available traps using lure @ 20-25 traps/ac. In areas, where bandicoot is a problem, wonder traps/multi-catch traps work better and enable to trap more animals int a single trap. · Identify live rodent burrows and smoke the burrows with burrow smoker for 2-3 minutes · Erect owl perches @ 12-15/ac to promote natural control of rodents Chemical control: · In cases of high level of infestation (>50 live burrows/ac) practice poison baiting with zinc phosphide @ 2.0% on community approach. PRACTICE PRE-BAITING TO AVOID BAIT SHYNESS Day 1: Close all the burrows in the fields, field bunds, canal bunds and surrounding barren lands etc. Day 2: Count the re-opened burrows and practice pre-baiting @ 20 g/burrow (98 parts of broken rice + 2 parts of edible oil) Day 4: Observe the re-opened burrows and treat the burrow with zinc phosphide poison bait (96 parts of broken rice + 2 parts of edible oil + 2 parts of zinc phosphide) @ 10g/ burrow. Collect the dead rats, if found any outside and bury them.

Source: NIPHM and Directorate of Plant Protection, Quarantine & Storage