3) SPRINGTAILS:
- Adults are silver grey to ground colour with light violet band along the sides of the body and black cellular fields present on the head. Body length is 0.7 to 2.25 mm and abdomen 4-6 segmented. Antennae are 3-6 segmented. Lepidocyrtus sp., L. cyaneus, Seira iricolor, Achorutes armatus etc. are the main species damaging mushrooms.
Life cycle:
- Springtails enter the mushroom house mainly through organic matter. .A female lays about 10-40 eggs which are smooth, spherical, white and measure 0.19 mm .The eggs hatch in 30 days at 30 ºC. Life cycle ranges from 70 – 78 days at 26 ºC.
 Fig. Showing the morphology of spring tails
- Springtails cause damage to the oyster, button and shiitake mushrooms. Staying in groups in the dark , they feed on mycelium in the compost resulting in disappearance of mycelium from spawn – run compost. Fruiting bodies of button mushrooms are also attacked causing slight pitting or browning at feeding sites. In oyster and shiitake, they feed on gills destroying the linings and also eat out the mycelial strands at base of the stipes.
Control methods:
- Preventive measures like clean cultivation, proper pasteurization of compost and casing materials, proper disposal of spent compost, raising the crop above floor level etc; should be followed.
- Use of 0.05 % malathion as spray for disinfection, mixing diazinon 30 ppm in compost at the time of filling and spray of insecticides like malathion or dichlorovos at 0.025 – 0.05 % conc. during spawn run and cropping have been recommended for their control.
4. BEETLES:
- Some beetles ( Staphylinus sp , Scaphisoma nigrofasciatum ) have also been found to cause serious damage to the oyster mushroom crop. These tiny insects are dark brown in colour with short elytra and large membranous hindwing and tip of the back culled over its body. The beetle Scaphisoma nigrofasciatum is deep amber coloured, with its head hypognatus and top of the abdomen not fully covered with elytra.
 Fig. Photographs of beetles as mushroom pests. (a) Beetle feeding the mycelial layer of mushroom (b) an adult beetle with its larva
- The grubs are found to feed voraciously on the mycelium and spawn, making tunnels in the stipe, pileus and gills of mushrooms. The infested fruiting bodies turn into abnormal shape and rotten masses. Grubs are seen hiding in between the gills of oyster mushrooms. The insect has been found to complete its life cycle within three weeks.
Control methods:
- Strict hygiene
- Proper pasteurization of straw.
- Application of chlorinated water or bleaching powder on cropping beds .
5) MUSHROOM NEMATODES:
- Nematodes, especially the myceliophagous nematodes are the most numerous and harmful creatures. Also known as eelworms, these are microscopic, thread like roundworms which live in soil, decomposing organic matter, fresh or salt water, also living on host plants, fungi, insects and animals.
Sources of infestation:
- Compost ingredients like wheat straw, chicken manure, horse manure, saw dust, pig manure, cotton cake; farm soil, air, water; casing materials like FYM, spent compost, moss pea , forest soi ; wooden trays, shelves and other containers etc; can be the primary source of infestation.
Spread:
- Once these nematodes get entry into the mushroom house, they further spread through air, faulty spray of water, workers’ hands, implements, mushroom flies, mites etc.
Types of nematodes :
- The mushroom nematodes are of following two types:
- Mycophagous or myceliophagous naematodes
- Saprophagous nematodes
I. Myceliophagous nematodes ( Aphelenchoides composticola, Aphelenchoides agarici, A. neocomposticola, Ditylenchus myceliophagous ) :
- These nematodes feed directly on mushroom mycelium and the fruit bodies. They are provided with a special type of mouth part i.e. stylet or needle with which these parasites puncture the hypha, inject digestive juices and suck the cellular contents leaving hyphal cell damaged which soon dies as it is drained of its cytoplasm. Since they have the capacity to multiply rapidly, these tiny pests millions in number, attack the mycelium moving from cell to cell and destroy the whole mycelial network in the compost within no time. The nematodes can reproduce 30 – 100 fold in about two weeks at 70 – 75 º F.
Fig. Showing: (1) the morphology of an adult myceliophagous nematode and its anterior body part with stylet,
the needle like sucking mouth part and (2) bulbous oesophagous
 Fig. Showing (1) the morphology of a saprophagous nematode (2) with its tubular mouth part and bulbous oesophagous
- The compost surface sinks
- Mycelium grows sparsely in patches and turns stingy
- The white mycelium starts disappearing from the infected mushroom compost leaving only the coarse strands showing black compost mass .
- Because of the build -up of high population of bacteria, compost becomes soggy and foul smelling.
- The pinheads turn brown, watery and remain stunted.
- The fruit bodies appear in patches in the beds
- Due to reduction in flush pattern and crop duration, the yield is drastically reduced.
Life cycle: The female generally lays eggs which hatch into small larvae. These larvae feed on the substratum and change into L-1 , L-2 , L-3 stages until they become adults and enter the reproductive stage. These have a life span of 7 – 12 days or more which again depends on the prevailing temperature.
II Saprophagous nematodes ( Rhabditis spp. ,Panagrolaimus spp. Diplogaster spp. ):
- These are having a tube –like mouthpart instead of a stylet through which they suck the nutrient particles of the substrate, including mushroom compost, suspended in fine films of water. Since bacteria are present in large number in mushroom compost as well as in the casing , these materials provide excellent breeding grounds for saprophagous eelworms. Presence of saprophytic nematodes indicates improper hygiene, faulty pasteurization of compost or the casing mixture and imbalanced growing conditions.
Nature of damage :
- With their tube like mouthparts, they are structurally incapable of causing any direct damage to mushroom mycelium . Due to their faecal materials, the Rhabditids not only spoil the structure and quality of composts in cropping beds emitting foul smell, but also cause inhibition of mycelial growth, reduction in yield due to disturbed flush pattern, reduction in crop duration and quantitative loss of the sporophores etc.
Control methods:
- Complete hygiene
- Proper pasteurization of compost and casing materials
- Drenching mushroom houses and premises with some disinfectants
- Use of fresh polythene bags and sterilization of empty trays or trolleys with formalin or other disinfectants
- Use of nematode free spray water
- Workers should wear clean overalls, including hand gloves and first harvest the healthy sporophores carefully and only then the older infected ones
- Cook out of the exhausted compost at 71± 1 º C for 8 – 10 hours
- Disposal of spent compost at a distant place
- Growing resistant mushroom varieties like Agaricus bitorquis , Pleurotus sajor-caju , Stropharia rugoso-annulata etc.
- Nematode trapping fungi like Arthrobotrys oligospora , A. superba , A. robusta and several species of Pleurotus can be used as bio- control agents against mushroom nematodes .
- Mixing of plant extracts of neem , castor, groundnu , karanj etc. in compost at the time of spawning or cropping.
5) ANIMAL PESTS
1. Rats: Apart from the Insect-pests and nematodes, some animal pests like rats also cause the damage. In fact they feed on the cereal grains used as substratum for spawn production, but they disturb and damage the beds a lot.
Control methods:
- The rooms should be rat proof and
- Mouse traps should be used
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