The goal of this project is to explore six different shiitake strains and the impact on yields they have. We hope to find out if different shiitake strains increase yield for log cultivation. We will also note if the strains perform similar on indoor sawdust blocks to determine if faster methods of strain research can be used.
Shiitake mushroom cultivation is expanding in the Northeast. According to projections in SARE Project ONE14-214 northeast shiitake log growers plan to expand from 17,968 bolts to 59,575 bolts by 2018. 100% of indoor growers who responded to our survey plan to expand shiitake production. The objective of this increased production is to meet demand for high quality locally produced shiitake mushrooms. This proposal aims to meet that goal by growing mushrooms more efficiently rather than increasing the amount of substrate used in cultivation. Through proper strain selection growers can increase the amount of mushrooms produced without increased investments. Many leaders in mushroom cultivation like Dr. John Holliday, Dr. Paul Stamets, and Dr Shu-Ting Chang emphasis strain selection as a critical first step in mushroom cultivation. Several researchers have tested shiitake strain yields, but most studies are outdated and no trial has been conducted in the northeast. This proposal will allow us to cultivate six strains of shiitake mushrooms on logs (outdoors) and sawdust blocks (indoors). The yields from each strain and substrate will be measured and information like morphology, storage, and disease resistance will be noted. The logs will take 2 ½ years to receive sufficient data while the sawdust will be completed in 6 months. This information will be submitted to the Mushroom Growers Newsletter, Commercial Mushroom Growers Network, Cornell Mushroom listserv, posted on our website, shared through our newsletter with over 600 people, and provided through 2 on farm workshops.
We would like to have clear data trialing different strains using common cultivation methods for shiitake mushrooms. This project would give farmers the information to make decisions on what spawn to buy to maximize their investment of labor and resources. We aim to increase production of shiitake mushrooms in the northeast by suggesting the highest yielding strains. In each trial we will record yields for the six different strains and note differences in traits like morphology, storability, and resistance to disease. The substrates we will use are supplemented oak sawdust and oak logs. These are the two methods used by indoor and outdoor growers respectively.
Strain to strain yields will then be compared between the two substrates to see if differences in yields can correlated across substrates. This provide a precedent for future log growers and spawn producers to trial strains on sawdust, giving them data to adjust production methods within months rather than the years of trialing required for log cultivation.
Six shiitake strains will be grown on supplemented sawdust and logs and tested for yields, disease, morphology/mushroom quality and storage life. The 6 strains originally used were 3782, 75, straw, CS, WR-46, and Lambert 123. The first four strains are high yielding strains from the aloha study, WR46 was the highest yielding strain from the Burhn et al 2009n and Sabota 1996, and Lambert 123 is used in large scale indoor shiitake cultivation. The process for inoculating sawdust blocks is as follows
1) acquire spawn
2)sawdust, wheat bran, and gypsum are mixed at a volume ratio of 100 gallons to 25 gallons to 1 gallon and then moistened to 50-60%.
3) Sawdust is bagged into 5 lb “blocks” in specialized filter patch bags and sterilized using atmospheric steam for 24 hours.
4) Blocks are then inoculated with a 1/2 cup of shiitake mycelium, sealed, and placed into incubation for 8 weeks.
5) Once browned blocks are cold shocked at 37 degrees for 24 hours to initiate fruiting.
6) The filter bags are removed and blocks are placed into the fruiting room which is held between 55-70 degrees with humidity at about 85% and CO2 levels between 600-900.
7) Fruiting will occur over the next 2 weeks, total fresh weight will be measured and biological efficiency will be calculated.
Dylan Kessler is no longer working on this project. Dylan helped to inoculate the first batch of sawdust grown shiitakes. Willie inoculated 100 logs in April of 2016 using 5 different strains. Willie also fruited the first trial of shiitake sawdust blocks.This year we inoculated 100 logs. 20 each for the strains CS, WR46, 3782, 75, and L123. The logs were stacked in the shade and have been incubating since April. All logs were from the same tree, a large sugar maple. There has been some contamination in the form of Schizophylum commune, which has showed up this fall on the logs. Logs were watered 3 times during the summer with a sprinkle for about 8 hours each time. It was an exceptionally dry year in Massachusetts. Fruiting and data collection will happen over the next 2 years for these logs.
The sawdust trials were put on hold after Dylan decided to not continue the grant in April. Many of the bags from the first trial become contaminated and the ones, which were fruited, produced almost no mushrooms, for any strain. The 2nd sawdust trial was run in the spring of 2017. One hundred and twenty more logs were also be inoculated again in spring of 2017 to give more validity to the strain trials.
We collected starting in June of 2017 and will continue being collected through October of 2018 and then will be published.
In 2017, two additional indoor fruiting trials were conducted. The first had extremely poor fruiting, with only CS and Straw fruiting mushrooms. The second all blocks fruited except for straw.
|STRAIN||# of BLocks||Total harvest||Average yield/ block|
Out of the 5 strains trailed, CS had the highest biological efficiency. The CS blocks had few large mushrooms. The mushrooms also had a tendency to deform much more than the other strains with large stems making the sale of these mushroom questionable. 75 likewise had few large mushrooms, less deformations, but still bulbous stems that the caps were growing out of. Both of these strains were rather uniform between the blocks that were fruiting, none of the blocks having large pinsets but all of them putting out several large mushrooms.
WR46 was less consistent with some blocks not fruiting at all and some blocks putting out several larger mushrooms. None of these seemed like viable commercial indoor cultivation strains because of the deformation of mushrooms and mediocre yields. 3782 had very inconsistent fruiting from block to block but several of the blocks fruited prolifically, having over 1 lb per block. If this strain was fruited more consistently it could easily out-compete the other strain in indoor cultivation.
In 2018 we reran this trial using different commercial mushroom strains. Over the last 2 years through conversations with other growers and trials we have seen that there are other commercial strains that are better suited for indoor cultivation than the strains we initially tested. For blocks in 2018 trialed running 3782, 3790, LE10, 236, and WR46. We will compare yields of these blocks to each other and to the trials run in 2017.
Started to fruit this year after 2016 inoculation. The first fruiting was forced in June. The yield data for this round was lost. After all data was placed directly into the computer to ensure data would not be lost again. The logs were forced fruited again in August with the following yield data.
During the harvest WR47 and 3782 respectively produced 13.36 and 9.55 pounds. Less than 4 weeks later 3782 put out another fruiting of 5 lbs Bringing total fall harvest off of 20 logs to 14.55 pounds. The other three strains of shiitake did very poorly fruiting less than 2 pounds over 20 logs. Again through conversations with other growers and our trials we have found other strains that may be more suited to log cultivation. It seems in general shiitake strains are suited to one method of cultivation better than another. We are excited to continue to see that Wr46 and 3782 seem to have good capacity to fruit well in both indoor cultivation and outdoor log cultivation. In fall of 2017 100 more logs were inoculated with 6 strains to continue testing different strains of commercial shiitake strains that may improve yields. The 6 strains are WR-46, Native harvest, Fungi Perfecti, Mushroom Mountain, 3790 and 3782. These logs are incubating indoors at 50-55 degrees to encourage fast spawn growth. We hope to see fruiting in the fall of 2018.
2018 update: In 2018 a fifth indoor fruiting was conducted using 4 strains. Of these 3782 was the largest producer with 3790 close in average pound per block. Both were at or above 1 pound per block. 3790 had firmer and larger mushrooms decreasing harvest time, increasing shelf life, and being a higher value product for consumers/chefs.
|3790 (15)||46 (20)||3782 (20)||236 (16)|
Logs: The logs that were inoculated in fall of 2017 did not fruit. Willie attended a workshop run by Field and Forest to fully learn the process of conducting spawn run over the winter. This method will be shared in the guidebook developed and published in early spring 2019. The logs inoculated in 2016 were force flushed in July and then allowed to naturally fruit in the fall as there was heavy amounts of rainfall. In the July fruiting WR-46 produced 17 lbs. All other strains produced a small amount of mushrooms.
In the September fruiting
So far we have not seen a strong correlation between yields fruiting on logs and yields fruiting on supplemented sawdust. Two strains inoculated on logs are producing well and have the possibility to improve yields in the growing field of log cultivation. Those two are 3782 and WR-46. This year we will trial those against 4 other strains to see if we can continue to get good data on high yield shiitake strains for log cultivation.
2018: Spawn run conducted indoors needs to be monitored and temperature carefully controlled to get fruiting in under 12 months. It seems from attending a workshop at Field and Forest this is possible with the right garage or lightly heated space. 3782 and 3790 are good strains to grow on indoor supplemented blocks. WR-46 continued to produce very strongly in 2018 while all the other strains dramatically decreased production. Trialing strains on supplemented sawdust for their potential in fruiting on logs does not work.
Education & Outreach Activities and Participation Summary
Three in person consultations with farmers were conducted. Farmers were shown around the farm, how supplemented blocks are produced and given a summary of the strain trials in progress.
Two tours were given to students from Umass Amherst in the Sustainable food and farming major. These students were introduced to the concept of cultivating mushrooms on logs and given an update on the strain trials, a total of 40 students.
Three youtube videos were created and shared via facebook on the laying yard, the process of shiitake log inoculation, and showing the different strains fruiting https://www.youtube.com/watch?v=zQGFNiNof7M
Two talks at the NOFA summer conference, in combination attended by 50 people.
One workshop hosted on the farm discussing how to inoculate logs and progress of research, Attended by 30 people.
Production of a guidebook is in progress. This will outline the process of cultivation for both indoor supplemented sawdust and outdoor logs. Research data will be presented in an easily digestible manner with recommendations of strain selections and future trials.