Saludo

CHAP 5 DISEASES & PESTS

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Chapter 5
MUSHROOM DISEASES and PESTS
If the cultivation of mushrooms is an art, then we must give them the best care we can, as an artist cares for his pictures. If it is a science, we must learn how to care for them, so that we get the highest yields. Those two aims are clearly compatible, in either case we need to understand what is required to give the bestresult. Diseases and pests often happen by themselves. A growers job is to keep them from happening. Fungicides, insecticides and other chemicals may help, but as Benjamin Franklin said, “an ounce (28 g) of prevention is worth a pound (454g) of cure.” We might say, prevention is worth 16 times as much as a cure. Before we can understand what is needed for prevention we need to understand howdiseases and pests get into our crop and how they are spread.

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OYSTER MUSHROOM CULTIVATION
1.Air 2.Water 3.People 4.Substrate 5.Spawn

There are five primary ways that things get in and are spread:

Fungal spores, bacteria and viruses can all be blown in with our required air supply and insects can fly in, sometimes even against the flow of air. Viruses may be carried, by fungal sporesand the insects can carry all of the other problems. Water can carry almost the same things air carries, but insects may only arrive as eggs, in water. Water may also carry nematodes. All of our problems can hitch a ride on people. Clean hands and clothing are particularly important. It is wise to keep those who do the pasteurization and spawning away from growing rooms, especially as the crop getsolder. It is also wise to keep those who work in growing rooms away from the spawning area. If substrate is properly pasteurized, it will start out free of diseases and pests. Proper pasteurization assumes that the material used was not already heavily contaminated with microorganisms before it was pasteurized. Although freshly pasteurized substrate should never be a source of diseases and pests,if any diseases or pests get started growing in it, the substrate becomes a source of more problems. If you have problems with pests or diseases, your substrate is a problem. Spawn should never be a source of problems, but sometimes it is. The best spawn makers are very careful to keep out all diseases. If spawn does not look good, it should certainly be rejected. It should never have insects, butsome diseases are difficult to detect. Viruses are particularly difficult and will probably not be detected by any, but the most sophisticated suppliers of spawn. Spawn is where the crop starts, so growers must be careful to only get the best.

CHAP 5 DISEASES & PESTS
HOW TO KEEP DISEASES AND PESTS OUT

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While most diseases and pests happen by themselves, we know how most happen and weknow that if we pay close attention to sanitation or, if you prefer hygiene, we can prevent them. The simplest description of sanitation is keeping everything clean. What I mean is that plus a little more. We can break it down into the important parts: 1.Clean water 2.Filtered air 3.Careful pasteurization 4.Clean workers 5.Clean surroundings CLEAN WATER Clean water is needed for every othersanitation need. Water that is not clean can carry diseases and even pest eggs. Obtaining clean water can be difficult. In most places a deep well (ca 30 m or more) will be good. Surface water (river, lake, etc.) should be filtered and chlorinated. The best and proper way to install a good water supply using surface water is really the job for someone well trained in water treatment. However, anythingthat can be done to have clean water is desirable. Clean water is probably less important for pasteurization than for any other growing need! That might suggest a way to treat water for other purposes. WATERING Even clean water can spread disease if it is sprayed on a diseased area and it splashes. While the Rose-head sprinkler is often recommended, it does splash. A mist sprayer will not...