Mushroom variety named ‘RO10425’

Abstract

A new and unique brown variety of the mushroom Agaricus bisporus Imbach was produced by crossing the progeny of brown mushrooms and off-white hybrid mushrooms to bridging cross strains. The resultant hybrid, named ‘RO10425’, exhibits distinct and stable characteristics. Hybrid ‘RO10425’ exhibits a lighter cap color, thicker cap flesh, and rounder cap, especially when compared to available brown mushroom varieties. ‘RO10425’ also exhibits fast mushroom development and high yield.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 63/685,196, filed Aug. 20, 2024, and U.S. Provisional Application No. 63/733,289, filed Dec. 12, 2024, which are hereby incorporated by reference in their entirety.

Latin name Genus and species: The mushroom cultivars of this disclosure are identified as Agaricus bisporus Imbach.

Varietal denomination: Variety denomination: The variety denomination is ‘RO10425’.

BACKGROUND OF THE INVENTION

The cultivated white button variety of Agaricus bisporus, known as A. bisporus (Lange) Imbach (syn. A. brunnescens Peck), is the predominant mushroom species in cultivation in the world today. After many years in which commercial mushroom sales in the United States were restricted primarily to white-capped A. bisporus mushrooms, there has been a recent trend toward increased sales of brown-capped A. bisporus mushrooms of various types and other so-called exotic strains (species other than A. bisporus). Improved agronomic characteristics can be introduced into the hybrid strains that can influence producer profitability. For instance, strains may have different ancestry, which will be reflected directly by the genotype and indirectly, in some cases, by the phenotypical characteristics. Generally speaking, strains may be differentiated on the basis of traits associated with the hybrid strains, such as, but not limited to, cap shape, surface texture, flesh thickness, color, shelf life, basidial spore number, sporelessness, resistance to infection by, symptoms of, or transmission of bacterial, viral or fungal diseases, amongst many other traits, to give some examples. Many of these traits directly contribute to factors that influence productivity, revenue capture, reduced costs, crop performance, and consumer and market demand.

In the endeavor to produce new mushroom varieties possessing desirable and improved characteristics, a preferred method is the crossing of homokaryons, ‘homokaryons’ being a multinucleate haploid fungal culture possessing a single line (somatic lineage) that is capable of undergoing plasmogamy with one or more other homokaryons. Each genetically different homokaryon is representative of a parent line in a resultant heterokaryon. The degree of success of each strain and the profitability of producers can be improved by the appropriate selection of the parental lines. Additionally, improved visual appeal and improved shelf-life, amongst many other characteristics, can also contribute to increased sales for mushroom growers in the world today. Thus, there are many characteristics by which a novel strain might be judged as superior in a particular production facility or a sales market, regionally or globally.

It is also well understood that an industry relying extensively only on a single genetic lineage is at increased risk of unpredictable, catastrophic crop failure on a worldwide scale due to the spread of diseases. To alleviate this type of problem, development and cultivation of new hybrid strains with independent lineages will help to act as a disease break. Further, it is highly desirable to simultaneously provide both genetic diversification and commercially acceptable improved crop characteristics. Thus, the need continues to exist for new brown hybrid strains of Agaricus bisporus with improved and preferred characteristics.

BRIEF SUMMARY OF THE INVENTION

It is an object of the disclosure to provide a brown variety of Agaricus bisporus mushroom with improved commercial characteristics relative to existing brown commercial mushrooms. Strains of the new brown variety, as well as qualities of this new variety, are described herein.

The following traits have been repeatedly observed and are determined to be the unique characteristics of the novel brown Agaricus bisporus mushroom strains. Specifically, it is an object of the disclosure to provide mushrooms that have one or more (most preferably all) of these following characteristics (relative to brown Agaricus bisporus now being marketed).

These characteristics in combination distinguish ‘RO10425’ as a new and distinct brown variety:

• • 1. Faster or similar timing to reach pinset and harvestable maturity.
  • 2. High yield, especially during the second break.
  • 3. Medium-dark brown cap color.
  • 4. Incompatibility with other available brown strains.
  • 5. Descent from a commercial off-white hybrid Agaricus bisporus mushroom variety (Amycel® XXX).
  • 6. Descent from a bridging cross strain.
  • 7. Round cap shape.
  • 8. Cap apex flesh thicker than marketed brown varieties.
  • 9. Cap edge flesh thicker than marketed brown varieties.

These and other objects of the disclosure have been accomplished by providing a hybrid Agaricus bisporus mushroom strain obtained by crossing a mushroom of wild strain AA-0096 or a progeny thereof with a second Agaricus bisporus strain comprising a commercial off-white hybrid strain (Amycel® XXX), wherein the mushroom of the disclosure (1) has (a) at least one genetic characteristic of wild strain AA-0096 not present in the second Agaricus bisporus strain, (b) at least one genetic characteristic of the second Agaricus bisporus strain not present in wild strain AA-0096, and (c) at least one genetic characteristic of the bridging cross strain and (2) has at least one physical characteristic selected from the group consisting of cap color, cap roundness, cap apex flesh thickness, cap edge flesh thickness, cap texture, and tray coverage that is statistically different from the corresponding physical characteristic of comparison strains ‘BR06’ (U.S. Pat. No. 7,608,760 B1) or ‘B14528’ (U.S. Pat. No. 9,017,988 B1).

Another feature of the present disclosure includes a new brown hybrid mushroom having improved agronomic traits leading favorably to increased consumer and market demand, productivity, crop performance, and revenue. Of particular interest and novel advantage are the superior morphological traits exhibited by ‘RO10425’, namely its yield as high and developmental timing as fast as other commercial brown mushrooms while also exhibiting high percent harvested speed and thick-fleshed morphology, which reflects higher quality than other commercial brown mushrooms. This morphology remains more consistent at later breaks for ‘RO10425’ when compared to other commercial varieties, and this increases visual appeal of sliced product. Pre-sliced button mushrooms have been growing in popularity over the last 10+ years; a 10-year report on mushroom sales trends demonstrated that sliced product has eclipsed whole product fresh mushroom sales, encompassing over 50% of fresh brown mushrooms sold in 2023 in the United States (Roerink, A. (2023, October). Ten-year Trends in Fresh Mushroom Sales. Mushroom Council. Available on the worldwideweb at mushroomcouncil[dot]org/wp-content/uploads/2023/10/Ten-Year-Fresh-Mushroom-Trends[dot]pdf).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows comparisons between mushrooms of variety ‘RO14176’ (top row) and variety ‘RO10425’ (bottom row). The top left panel shows caps of 10 representative mushrooms from variety ‘RO14176’ and their average L*, a*, and b* values. The top right panel shows a longitudinal slice of each mushroom cap in the top left panel with the 10 mushrooms' average cap diameter, cap height, cap flesh thickness, and stipe diameters reported in millimeters. The bottom left panel shows caps of 10 representative mushrooms from variety ‘RO10425’ and their average L*, a*, and b* values. The bottom right panel shows a longitudinal slice of each mushroom cap in the bottom left panel with the 10 mushrooms' average cap diameter, cap height, cap flesh thickness, and stipe diameters reported in millimeters. Mushrooms pictured were grown in the same room, under the same environmental conditions, and were harvested from the same trial in April 2025. All photos have the same scale. Scale bar=1 cm.

FIG. 2 shows a longitudinal slice of a mushroom of variety ‘RO14176’ with markings added to illustrate the calculation of Cap Edge Flesh Thickness, where Cap Edge Flesh Thickness is calculated by ((LG_L−CS_L)+(CS_R−RG_R))/CS_D. LG_L=left-most x-coordinate of the left gill, CS_L=left-most x-coordinate of the cross-section, CS_R=right-most x-coordinate of the cross-section, RG_R=right-most x-coordinate of the right gill, and CS_D=diameter of the cross-section.

FIG. 3 shows a longitudinal slice of a mushroom of variety ‘RO14176’ with markings added to illustrate the calculation of Cap Apex Flesh Thickness, where Cap Apex Flesh Thickness is calculated by (CS_T−((LG_T+RG_T)/2))/CS_H. CS_T=the top-most y-coordinate of the cross-section, LG_T=the top-most y-coordinate of the left gill, RG_T=the top-most y-coordinate of the right gill, and CS_H=the height of the cross-section.

FIG. 4 shows multiple mushroom caps of variety ‘RO10425’ from a top-down view.

FIG. 5 shows multiple longitudinal slices of mushrooms of variety ‘RO10425’.

DETAILED BOTANICAL DESCRIPTION

In mushroom breeding, mycelial (=vegetative) cultures of two compatible progenitors (typically these are haploid homokaryotic strains called homokaryons) must come into physical contact so that one or more fusion zones can occur between the progenitors. Within those fusion zones nuclei from the two progenitors become associated. In Agaricus bisporus, a novel, hybrid mycelium ultimately containing two compatible haploid nuclear types (one from each of the two progenitors) plus one mitochondrial type (from either one of the progenitors) emerges. This novel hybrid mycelium can be isolated and propagated to provide the new hybrid culture, which can be further subdivided and propagated for commercial or other purposes.

It should be recognized that the mushrooms of the present disclosure are hybrids (equivalent to crosses), as they are formed by the hybridization of at least two independently derived strains, since they were formed by hybridizing the wild strain AA-0096 with a second, commercialized strain of A. bisporus (with the second strain, in some embodiments, being itself a cross between at least two other identified strains of A. bisporus, i.e., Amycel® XXX). The term ‘hybrid mushroom’ may be used herein to represent the product of a cross between a wild A. bisporus strain and a commercial strain, often including a cross between a brown mushroom strain and an off-white hybrid variety (Amycel® XXX). Differences in terminology (and in the specific techniques used alongside the terminology) are merely indicative of the variety of terminology and techniques used in the mushroom production field.

After parental homokaryotic spores germinated into mycelia, single spore isolates (SSIs) were selected, preferentially those exhibiting slow mycelial growth. The slowly growing mycelia of SSIs usually contain one nuclear type, are thus homokaryotic, and are suitable for crossing, and thus for breeding. Slow growers are denoted as “sg”. Some homokaryons were obtained through protoplasting; this technique involves treating the vegetative mycelia of the heterokaryons to damage the fungal cell wall, then selecting colonies of protoclones that are each derived from a single, regenerated protoplast. All crosses were initially cultivated on a small scale, and spores were collected for the parents of the crosses to produce the hybrids described herein.

One useful feature in the breeding programs for these novel mushroom varieties is the use of a bridging cross strain, which is a hybrid variety produced from crossing a commercial brown variety with a commercial white variety. The particular bridging cross strain of note in these breeding programs is known as the 4x29 strain. Strain 4x29 has been previously deposited under the provisions of the Budapest Treaty with the American Type Culture Collection, Rockville, Md., USA, ATCC accession No. PTA-6877 (deposited on Jul. 20, 2005). Strain 4x29 is the product of crossing a commercial brown strain with a commercial white strain. The ‘29’ of this strain is a unique homokaryon collected from an off-white hybrid strain.

The varieties, mushrooms, strains, and cultures disclosed herein are understood to comprise parts of mushrooms, such as the fruiting body, cap, stipe, basidium, spore, mycelium, mixed or unmixed spawn, inoculated substrate, protoplast, gill, cell, or product produced from the mushroom. In some embodiments, the mushroom part from the hybrid mushroom produced by any method disclosed herein is a spore. In some embodiments, the mushroom part produced from a mushroom strain disclosed herein is a spore.

Trait Determinations

In the descriptions and tables that follow, numerous traits are calculated/measured as follows in Table 1. Visual depictions of the measurements used for calculating Cap Apex Flesh Thickness are shown in FIG. 3. Visual depictions of the measurements used for calculating Cap Edge Flesh Thickness are shown in FIG. 2.

Mushrooms were harvested at Stage 3 as described by Hammond & Nichols (Hammond, J. B. W., & Nichols, R. (1976). Carbohydrate metabolism in Agaricus bisporus (Lange) Sing.: changes in soluble carbohydrates during growth of mycelium and sporophore. Microbiology, 93(2), 309-320), when cap diameters were approx. 3-5 cm with the veil still intact. To reduce confounding effects introduced by different trials, developmental timing and yield traits were compared only from trials where all strains being compared were present together.

Images of mushroom caps and longitudinal cross-sections were captured using a Canon Rebel SL1 camera (Canon, Inc., Toyko, Japan) in a custom-built photo box with standardized lighting conditions. The camera was calibrated for color consistency using a ColorChecker gray balance card (Calibrite LLC, Wilmington, DE). L*, a* and b* values were captured across the surface of each mushroom cap and cross-section using ImageJ (Schneider, C. A., Rasband, W. S., & Eliceiri, K. W. (2012). NIH Image to ImageJ: 25 years of image analysis. Nature Methods, 9(7), 671-675). Images captured in 2024 and 2025 were used for analysis. Extreme outliers were excluded from the data, defined as those falling 3 times the interquartile range (IQR) above the 75th percentile for that trait or more than 3 times the IQR below the 25th percentile for that trait.

All statistical analyses were carried out in the R programming language (R Core Team, (2013). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available on the worldwide web at [dot]R-project[dot]org/). Levene's test was performed using the ‘car’ package (Fox, J., & Weisberg, S. (2018). An R companion to applied regression. SAGE Publications), Shapiro-Wilk tests and Tukey HSD were performed using the ‘stats’ package (R Core Team (2013)), and standard ANOVAs, Kruskal-Wallis tests and Dunn's tests were performed using the ‘rstatix’ package (Kassambara, A (2023). rstatix: Pipe-Friendly Framework for Basic Statistical Tests. R package version 0.7.2, rpkgs[dot]datanovia[dot]com/rstatix/).

TABLE 1
		Measurement
Trait	Tool	Scale	Timing
Cap	visually	0 to 5 (from	1st
Color	assessed	white to	break**,
Darkness		dark	2nd
		brown),	break**
		tray-level
		measurement
Cap	image	−128 to +127	1st
Color	analysis	(from pure	break**,
a* Value		green to	2nd
(Green-		pure red),	break**
Red)		individual
		mushroom-
		level
		measurement
Cap	image	−128 to +127	1st
Color b*	analysis	(from	break**,
Value		pure blue	2nd
(Blue-		to pure	break**
Yellow)		yellow),
		individual
		mushroom-
		level
		measurement
Cap	image	0 to 100	1st
Color	analysis	(from pure	break**,
L* Value		black to	2nd
(Dark-		pure white),	break**
Light)		individual
		mushroom-
		level
		measurement
Cap	image	millimeters	1st
Diameter	analysis	(mm),	break**,
		individual	2nd
		mushroom-	break**
		level
		measurement
Cap	manual	1 to 5	1st
Firmness	squeeze	(from very	break**,
	test	soft to	2nd
		very firm),	break**
		tray-level
		measurement
Cap	calculated	distance	1st
Apex	ratio and	from	break**,
Flesh	image	top	2nd
Thickness	analysis	of gills	break**
		to top
		of cap of
		mushroom,
		relative
		to cap
		height,
		individual
		mushroom-
		level
		measurement
Cap	calculated	sum of distances	1st
Edge	ratio and	from outer edge	break**,
Flesh	image	of each	2nd
Thickness	analysis	gill to	break**
		outer edges
		of cap of
		mushroom,
		relative
		to cap
		diameter,
		individual
		mushroom-
		level
		measurement
Cap	hand-	millimeters	1st
Flesh	measure-	(mm), distance	break**,
Thickness	ment	from top of	2nd
		gill-stipe	break**
		connection
		(at center
		of stipe) to
		top of cap,
		individual
		mushroom-
		level
		measurement
Cap	image	millimeters	1st
Height	analysis	(mm),	break**,
		distance	2nd
		from base	break**
		of cap
		to top of cap,
		individual
		mushroom-
		level
		measurement
Cap	image	Unitless ratio	1st
Roundness	analysis	(0-1), calculated	break**,
(Calculated)		as 4 * CSA/	2nd
		(π * CSD2),	break**
		where CSA =
		area of the
		cross-section,
		and CSD =
		diameter of the
		cross-section;
		assessed
		with image
		analysis,
		individual
		mushroom-
		level
		measurement
Cap	visually	1 to 5	1st
Roundness	assessed	(from very	break**,
(Visual)		flat to	2nd
		spherical),	break**
		tray-level
		measurement
Compatibility	calculated	pounds per	1st
	ratio	square	break**
		foot
		(lb/ft2) and
		kilograms
		per square
		meter (kg/m2),
		weight of
		1st break
		mushrooms
		yielded
		relative to
		area of tray,
		tray-level
		measurement
Compost	visually	0 to 5	before
Coloniz-	assessed	(from no	1st break
ation		colonization	(10 days
		to robust	after
		colonization),	spawning)
		tray-level
		measurement
Days	visually	number of days	1st
to 1st	assessed	elapsed after	break**
Break		casing at
		which at
		least half of
		tray is of
		harvestable
		maturity for
		1st break,
		tray-level
		measurement
Days	visually	number of days	2nd
to 2nd	assessed	elapsed	break**
Break		after
		casing at
		which
		at least
		half of
		tray is of
		harvestable
		maturity for
		2nd break,
		tray-level
		measurement
Days	visually	number	before
to Pinset	assessed	of days	1st break
		elapsed
		after
		casing
		at which
		pins first
		reach 5 mm,
		tray-level
		measurement
Percent	calculated	% of yield	17
Harvested	ratio	harvested by	days
Speed		a designated	after
		date	casing
		within break,	(1st
		yield at date	break),
		within break/	24 days
		total yield	after
		for break,	casing
		trial-level	(2nd
		measurement	break),
			32 days
			after
			casing
			(3rd
			break)
Relative	calculated	Cap	1st
Cap	ratio	Flesh	break**,
Flesh		Thickness	2nd
Thickness		Value/Cap	break**
		Diameter
		Value,
		individual
		mushroom-
		level
		measurement
Relative	calculated	Cap Height	1st
Cap	ratio	Value/Cap	break**,
Height		Diameter	2nd
		Value,	break**
		individual
		mushroom-
		level
		measurement
Relative	calculated	Stipe	1st
Stipe	ratio	Diameter	break**,
Diameter		Value/Cap	2nd
		Diameter	break**
		Value,
		individual
		mushroom-
		level
		measurement
Stipe	hand-	millimeters	1st
Diameter	measure-	(mm),	break**,
	ment	stipe	2nd
		diameter	break**
		at base
		of cap,
		individual
		mushroom-
		level
		measurement
Tray	visually	0 to 5	1st
Coverage	assessed	(from no	break**,
		coverage	2nd
		to full	break**
		coverage),
		tray-level
		measurement
Yield	weighing	kg/m2,	Assessed
(Each		tray-level	cumul-
Break)		measurement;	atively
		or	through-
		lb/ft2,	out
		tray-level	1st,
		measurement	2nd,
			and 3rd
			breaks
Yield	weighing	kg/m2,	Assessed
(Total)		tray-level	cumul-
		measurement;	atively
		or	across
		lb/ft2,	1st, 2nd,
		tray-level	and 3rd
		measurement	breaks
** = at date when at least half of tray is of harvestable maturity in break

Objective Description of the Variety ‘RO10425’

The following detailed description sets forth the breeding procedures and the characteristics of new cultivar designated ‘RO10425’. The strain is maintained and asexually propagated as vegetative mycelium. Spawn (inoculum for the substrate compost) is prepared from the vegetative mycelium. Specifically, the strain has been asexually propagated and maintained by vegetative mycelium in Royal Oaks, California, USA. The variety has shown uniformity and stability for the traits, within the limits of expected environmental influence for the traits.

All homokaryons utilized are strains of Agaricus bisporus.

Two initial homokaryotic strains were used for breeding. Wild brown strain AA-0096 was crossed with a commercial off-white hybrid mushroom strain.

More specifically, in a first cross, an AA-0096 slow growing SSI (sg) was crossed with a commercial off-white hybrid protoplast (p).

A progeny homokaryon resultant from this cross was then selected and backcrossed to the commercial off-white hybrid parent strain. A homokaryon produced by the backcrossing was then selected and crossed to a homokaryon of a bridging cross strain. This cross produced ‘RO10425’.

The nearest color on The Colour Chart of The Royal Horticultural Society of London (R.H.S.) (2015 edition) was identified by Eucliean distance in the International Commission on Illumination (CIELAB) color space, carried out using the farver package in R:

• • ‘RO10425’ Cap color: RHS 199D (dark greyish yellow)
  • ‘RO10425’ Stipe color: RHS 159C (pale orange yellow)
  • ‘RO10425’ Gill color: RHS N170D (moderate yellowish pink)

There are multiple characteristics of ‘RO10425’ distinguishable from other varieties, such as a different cap color, rounder cap shape, thicker cap apex flesh, thicker cap edge flesh, and higher or as high yield at second break compared to other available brown commercial strains. Other characteristics of ‘RO10425’ distinguishable from other varieties are described below (compared to commercial line ‘BR06’, commercial line ‘B14528’, and related variety ‘RO14176’).

FIG. 4 and FIG. 5 show mushroom caps and longitudinal slices, respectively, of strain ‘RO10425’.

Comparison to Other Mushroom Varieties

Initial Trials

Tray-Level Comparisons

In further evidence of the distinctness and superiority of mushroom strain ‘RO10425’, provided below are the results of trials conducted across multiple strains' yielded trays of mushrooms. These tray trials compare yield at each break. Characteristics were measured from 15 trays of strain ‘RO10425’ mushrooms and 23 trays of strain ‘BR06’ mushrooms (Table 2), and corresponding measurements were taken from 24 trays of strain ‘RO14176’ mushrooms (Table 3).

Table 2 below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘BR06’. Column 1 lists the tray-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘BR06’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘BR06’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 2
	‘RO10425’	‘BR06’
		St.		St.
Characteristic	Average	Dev.	Average	Dev.	p-value
First Break
Yield (lb/ft2)	1.61	0.64	2.54	1.29	1.33E−02
Second Break
Yield (lb/ft2)	1.69	0.48	1.47	0.51	1.92E−01
Third Break
Yield (lb/ft2)	1.32	0.41	0.75	0.50	8.12E−04
All Breaks Combined
Yield (lb/ft2)	4.62	0.61	4.76	1.24	6.79E−01

Table 3 below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘RO14176’. Column 1 lists the tray-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘RO14176’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘RO14176’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 3
	‘RO10425’	‘RO14176’
		St.		St.
Characteristic	Average	Dev.	Average	Dev.	p-value
First Break
Yield (lb/ft2)	1.61	0.64	2.54	0.83	7.01E−04
Second Break
Yield (lb/ft2)	1.69	0.48	1.91	0.52	1.91E−01
Third Break
Yield (lb/ft2)	1.32	0.41	0.92	0.38	3.41E−03
All Breaks Combined
Yield (lb/ft2)	4.62	0.61	5.37	1.08	1.94E−02

Individual Mushroom-Level Comparisons

In additional evidence of the distinctness and superiority of mushroom strain ‘RO10425’, provided below is a summary of precise quantitative measurements of individual mushrooms at first and second breaks. These data compare Cap L* Value, Cap a* Value, and Cap b* Values in the CIELAB color space, Cap Diameter, Cap Height, Cap Flesh Thickness, Stipe Diameter, Relative Cap Height, Relative Cap Flesh Thickness, and Relative Stipe Diameter (as described in Table 1). Measurements from 49 first break and 37 second break ‘RO10425’ mushrooms were compared to 80 first break and 40 second break ‘BR06’ mushrooms (Table 4).

Table 4 below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘BR06’. Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘BR06’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘BR06’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 4
	‘RO10425’	‘BR06’
	Ave-	St.	Ave-	St.
Characteristic	rage	Dev.	rage	Dev.	p-value
First Break
Cap L* Value	65.84	5.15	62.20	5.58	3.22E−04
(dark-light)
Cap a* Value	7.51	0.99	9.43	1.15	5.94E−17
(green-red)
Cap b* Value	26.03	1.29	28.67	1.63	7.91E−17
(blue-yellow)
Cap Diameter	43.45	3.41	44.05	3.80	3.70E−01
Cap Height	27.09	1.99	27.45	1.99	3.27E−01
Cap Flesh	15.03	1.42	14.57	1.46	8.09E−02
Thickness
Stipe Diameter	21.66	2.08	20.03	2.08	3.18E−05
Relative Cap	0.62	0.03	0.62	0.04	9.82E−01
Height
Relative Cap	0.35	0.04	0.33	0.03	1.61E−02
Flesh
Thickness
Relative Stipe	0.56	0.05	0.53	0.03	1.02E−03
Diameter
Second Break
Cap L* Value	64.44	2.79	62.19	3.79	4.12E−03
(dark-light)
Cap a* Value	7.05	0.79	7.99	1.07	3.86E−05
Cap b* Value	26.48	1.15	27.01	1.06	3.64E−02
(blue-yellow)
Cap Diameter	45.20	3.51	41.98	4.43	7.39E−04
Cap Height	28.78	2.27	26.81	2.89	1.42E−03
Cap Flesh	15.19	1.61	14.30	1.53	1.54E−02
Thickness
Stipe Diameter	20.90	2.02	18.74	3.24	8.38E−04
Relative Cap	0.64	0.04	0.64	0.03	8.37E−01
Height
Relative Cap	0.34	0.04	0.34	0.02	5.52E−01
Flesh
Thickness
Relative Stipe	0.46	0.04	0.45	0.05	8.97E−02
Diameter

Additional analyses were performed on the measurements taken across individual mushrooms of each variety at multiple breaks, in order to compare more generalized mushroom traits irrespective of whether the mushrooms belonged to the first vs. second break of harvesting. The same characteristics described above (see Table 1) were measured from 86 mushrooms of strain ‘RO10425’ across the first and second break, and corresponding measurements were taken from 150 mushrooms of strain ‘BR06’ across the first and second break (Table 5).

Table 5 below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘BR06’. Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘BR06’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘BR06’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 5
	‘RO10425’	‘BR06’
		St.		St.
Characteristic	Average	Dev.	Average	Dev.	p-value
Cap L* Value	65.24	4.33	62.86	4.95	2.49E−04
(dark-light)
Cap a* Value	7.31	0.93	8.77	1.31	3.90E−17
(green-red)
Cap b* Value	26.22	1.24	28.31	1.61	5.99E−21
(blue-yellow)
Cap Diameter	44.20	3.55	42.84	4.00	9.33E−03
Cap Height	27.82	2.26	26.53	2.59	1.55E−04
Cap Flesh	15.10	1.50	14.01	1.68	1.12E−06
Thickness
Stipe Diameter	21.33	2.07	18.70	2.98	6.06E−12
Relative Cap Height	0.63	0.03	0.62	0.04	4.84E−02
Relative Cap Flesh	0.34	0.04	0.33	0.03	9.34E−04
Thickness
Relative Stipe	0.48	0.04	0.44	0.05	1.96E−12
Diameter

Table 6 below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘RO14176’. Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘RO14176’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘RO14176’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 6
	‘RO10425’	‘RO14176’
		St.		St.
Characteristic	Average	Dev.	Average	Dev.	p-value
First Break
Cap L* Value	65.84	5.15	65.91	4.79	9.38E−01
(dark-light)
Cap a* Value	7.51	0.99	7.49	1.05	9.32E−01
(green-red)
Cap b* Value	26.03	1.29	26.35	1.35	1.82E−01
(blue-yellow)
Cap Diameter	43.45	3.41	43.53	3.27	9.01E−01
Cap Height	27.09	1.99	27.89	2.12	3.55E−02
Cap Flesh Thickness	15.03	1.42	15.33	1.36	2.42E−01
Stipe Diameter	21.66	2.08	19.99	1.90	7.06E−06
Relative Cap Height	0.62	0.03	0.64	0.03	2.43E−03
Relative Cap Flesh	0.35	0.04	0.35	0.03	3.25E−01
Thickness
Relative Stipe	0.50	0.04	0.46	0.04	4.71E−07
Diameter
Second Break
Cap L* Value	64.44	2.79	65.61	3.67	1.24E−01
(dark-light)
Cap a* Value	7.05	0.79	6.36	0.76	2.32E−04
(green-red)
Cap b* Value	26.48	1.15	25.05	1.46	1.07E−05
(blue-yellow)
Cap Diameter	45.20	3.51	41.88	2.68	1.23E−05
Cap Height	28.78	2.27	28.22	2.12	2.65E−01
Cap Flesh Thickness	15.19	1.61	15.75	1.61	1.31E−01
Stipe Diameter	20.90	2.02	19.16	2.29	6.92E−04
Relative Cap Height	0.64	0.04	0.67	0.04	7.23E−05
Relative Cap Flesh	0.34	0.04	0.38	0.04	1.79E−05
Thickness
Relative Stipe	0.46	0.04	0.46	0.05	6.21E−01
Diameter

FIG. 1 shows representative caps and longitudinal sections of caps from mushrooms of strain ‘RO10425’ compared to mushrooms of strain ‘RO14176’.

Additional analysis was conducted for measurements taken across individual mushrooms of each variety at multiple breaks, in order to compare more generalized mushroom traits irrespective of whether the mushrooms belonged to the first vs. second break of harvesting. The same characteristics described above (see Table 1) were measured from 86 mushrooms of strain ‘RO10425’ across the first and second break, and corresponding measurements were taken from 170 mushrooms of strain ‘RO14176’ across the first and second break (Table 7).

Table 7 below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘RO14176’. Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘RO14176’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘RO14176’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 7
	‘RO10425’	‘RO14176’
		St.		St.
Characteristic	Average	Dev.	Average	Dev.	p-value
Cap L* Value	65.24	4.33	67.15	4.61	1.60E−03
(dark-light)
Cap a* Value	7.31	0.93	6.93	1.09	6.45E−03
(green-red)
Cap b* Value	26.22	1.24	26.44	1.59	2.60E−01
(blue-yellow)
Cap Diameter	44.20	3.55	42.36	3.30	5.22E−05
Cap Height	27.82	2.26	27.14	2.37	2.88E−02
Cap Flesh Thickness	15.10	1.50	14.70	1.84	7.93E−02
Stipe Diameter	21.33	2.07	18.53	2.68	1.68E−15
Relative Cap Height	0.63	0.03	0.64	0.04	2.54E−02
Relative Cap Flesh	0.34	0.04	0.35	0.04	3.75E−01
Thickness
Relative Stipe	0.48	0.04	0.44	0.05	2.98E−11
Diameter

Additional Trials
Tray-Level Comparisons

Several additional trials were conducted for characterizing ‘RO10425’. Table 8 below provides qualitative comparisons between mushroom strain ‘RO10425’ and strain ‘BR06’. Traits of particular interest are bolded. Column 1 lists the tray-level characteristics (as described in Table 1), column 2 shows the qualitative descriptor for the characteristic for mushroom strain ‘RO10425’ relative to ‘BR06’, and column 3 shows the qualitative descriptor for mushroom strain ‘BR06’ relative to ‘RO10425’.

	TABLE 8
	Characteristic	‘RO10425’	‘BR06’
Before First Break
	Days to Pinset	Similar	Similar
First Break
	Days to 1st Break	Similar	Similar
	Percent Harvested Speed	Similar	Similar
	Yield (kg/m2)	Similar	Similar
Second Break
	Days to 2nd Break	Similar	Similar
	Yield (kg/m2)	Higher	Lower
Third Break
	Yield (kg/m2)	Similar	Similar
All Breaks Combined
	Yield (kg/m2)	Similar	Similar

The calculations that informed these qualitative descriptors are shown in Table 9.

Table 9 below provides qualitative comparisons between mushroom strain ‘RO10425’ and strain ‘B14528’. Column 1 lists the tray-level characteristic (as described in Table 1), column 2 shows the qualitative descriptor for the characteristic for mushroom strain ‘RO10425’ relative to ‘B14528’, and column 3 shows the qualitative descriptor for mushroom strain ‘B14528’ relative to ‘RO10425’.

	TABLE 9
	Characteristic	‘RO10425’	‘B14528’
Before First Break
	Days to Pinset	Similar	Similar
First Break
	Days to 1st Break	Similar	Similar
	Percent Harvested Speed	Similar	Similar
	Yield (kg/m2)	Similar	Similar
Second Break
	Days to 2nd Break	Similar	Similar
	Yield (kg/m2)	Similar	Similar
Third Break
	Yield (kg/m2)	Similar	Similar
All Breaks Combined
	Yield (kg/m2)	Similar	Similar

The calculations that informed these qualitative descriptors are shown in Table 10.

The first part of analyzing trait measurements in the additional trials herein included making comparisons between all three of instant strain ‘RO10425’, comparative strain ‘BR06’, and comparative strain ‘B14528’. For these three strains, a Shapiro-Wilk test and a Levene test were performed first to assess if the data satisfy the assumptions of normality and equal variances among groups, respectively, of a standard ANOVA. The Shapiro-Wilk test and Levene test determined that most of these traits satisfied neither assumption. Therefore, a Kruskal-Wallis test (Kruskal, W. H., & Wallis, W. A. (1952). Use of ranks in one-criterion variance analysis. Journal of the American statistical Association, 47(260), 583-621), a non-parametric variation of ANOVA that does not assume normality, equal variances among groups, or equal sample sizes among groups, was performed. Medians and interquartile ranges (IQR) were reported, as these metrics are robust to non-normal distributions. Means are also reported for consistency with normally-distributed traits.

The Shapiro-Wilk test and Levene test determined that most developmental timing traits (Days to Pinset, Days to 1st Break, and Days to 2nd Break) and yield traits were not normally distributed and variances among groups were not equal. The Kruskal-Wallis test and Dunn post-hoc test (“Dunn's Test”; Dunn, O. J. (1964). Multiple comparisons using rank sums. Technometrics, 6(3), 241-252) were used in these cases. When the Kruskal-Wallis test results were significant based on a threshold of p<0.05, Dunn's test was performed post-hoc to make pairwise strain comparisons (Dunn, 1964). P-values were adjusted using the Bonferroni correction to minimize risk of Type 1 error (false significance). An exception to this trend was Percent Harvested Speed, which was normally distributed and exhibited equal variance for all strains. For assessing Percent Harvested Speed, a standard ANOVA was used and a Tukey Honestly Significant Difference (HSD) test was performed post-hoc for pairwise strain comparisons. Standard deviations multiplied by 100 for consistency alongside percentages (“SD*100”) were reported for this trait. This testing was performed on groups of three strains, as shown in Table 10, but the other results herein using this test show a pairwise subset of the tests for consistency with the initial trials.

In Table 10, column 1 shows each trait and the strains compared for said trait, column 2 shows the mean value for that strain's measurements of that trait, column 3 shows the median value of the same measurements, column 4 shows the interquartile range (“IQR”) for the same measurements, column 5 shows the number of trials conducted, and column 6 shows the statistical significance group calculated for that strain for that trait according to Dunn's Test. Traits of particular interest are bolded.

TABLE 10
					Signi-
				Num-	ficance
				ber	Group
				of	(Dunn's
Variety	Mean	Median	IQR	Trials	Test)
Before First Break
Days to Pinset
‘RO10425’	12.00	12.00	2.00	4	a
‘B14528’	12.00	12.00	1.75	4	a
‘BR06’	12.40	12.00	1.00	4	a
First Break
Days to 1st Break
‘RO10425’	18.00	18.00	1.00	4	a
‘B14528’	17.60	18.00	1.75	4	a
‘BR06’	18.10	18.00	1.00	4	a
Yield (kg/m2)
‘RO10425’	10.64	10.64	1.76	3	a
‘B14528’	9.81	9.52	4.44	3	a
‘BR06’	10.30	8.35	5.57	3	a
Second Break
Days to 2nd Break
‘RO10425’	24.90	25.00	1.75	4	a
‘B14528’	24.80	25.00	1.00	4	a
‘BR06’	25.30	26.00	1.00	4	a
Yield (kg/m2)
‘RO10425’	8.74	8.10	3.27	3	a
‘B14528’	7.13	6.93	1.51	3	ab
‘BR06’	6.20	5.86	1.61	3	b
Third Break
Yield (kg/m2)
‘RO10425’	3.66	3.52	0.78	3	ab
‘B14528’	5.81	5.42	1.81	3	b
‘BR06’	2.64	1.95	2.10	3	a
All Breaks Combined
Yield (kg/m2)
‘RO10425’	23.05	23.14	4.25	3	a
‘B14528’	22.75	22.61	2.29	3	a
‘'BR06’	19.14	18.70	5.52	3	a
Percent Harvested Speed			Significance
(measured in			Group
First Break)	SD * 100		(Tukey HSD)
‘RO10425’	36.7%	34.8%	32.70	3	a
‘B14528’	36.2%	45.2%	25.00	3	a
‘BR06’	28.9%	12.9%	37.70	3	a

Table 11 below provides additional quantitative comparison between mushroom strain ‘RO10425’ and strain ‘RO12756’ (U.S. application Ser. No. 19/305,683). Column 1 shows the strains compared for each trait, column 2 shows the mean value for that strain's measurements, column 3 shows the median value of the same measurements, column 4 shows either the interquartile range (“IQR”) or the standard deviation multiplied by 100 for consistency alongside percentages (“SD*100”) for the same measurements, column 5 shows the number of trials conducted, and column 6 shows the statistical significance group calculated for that strain for that trait according to either Dunn's Test or Tukey HSD.

TABLE 11
					Signi-
				Num-	ficance
				ber	Group
				of	(Dunn's
Characteristic	Mean	Median	IQR	Trials	Test)
Before First Break
Days to Pinset
‘RO10425’	12.00	12.00	2.00	4	a
‘RO12756’	11.42	11.00	1.00	8	a
First Break
Days to 1st Break
‘RO10425’	18.00	18.00	1.00	4	a
‘RO12756’	17.51	17.00	1.00	8	a
Yield (kg/m2)
‘RO10425’	10.64	10.64	1.76	3	a
‘RO12756’	11.91	12.40	4.88	8	a
Second Break
Days to 2nd Break
‘RO10425’	24.86	25.00	1.75	4	a
‘RO12756’	24.84	25.00	2.00	7	a
Yield (kg/m2)
‘RO10425’	8.74	8.10	3.27	3	a
‘RO12756’	8.54	8.15	2.64	8	a
Third Break
Yield (kg/m2)
‘RO10425’	3.66	3.52	0.78	3	a
‘RO12756’	4.78	4.83	1.86	8	a
All Breaks Combined
Yield (kg/m2)
‘RO10425’	23.05	23.14	4.25	3	a
‘RO12756’	25.29	24.95	4.15	8	a
Percent Harvested					Significance
Speed					Group
(measured in					(Tukey
First Break)	Mean	Median	SD * 100		HSD)
‘RO10425’	36.7%	34.8%	32.7%	3	a
‘RO12756’	48.2%	50.9%	16.3%	8	a

Individual Mushroom-Level Comparisons

In additional evidence of the distinctness and superiority of mushroom strain ‘RO10425’, provided below is a summary of precise quantitative measurements of individual mushrooms at first and second breaks. These data compare Cap L* Value, Cap a* Value, and Cap b* Values in the CIELAB color space, Cap Apex Flesh Thickness, Cap Edge Flesh Thickness, and Cap Roundness (Calculated) (as described in Table 1). Measurements were taken for hundreds of mushrooms per trait, noted as sample size (n) in Tables 12B and 13B.

Table 12A below provides qualitative comparisons between mushroom strain ‘RO10425’ and strain ‘BR06’. Traits of particular interest are bolded. Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the qualitative descriptor for the characteristic for mushroom strain ‘RO10425’ relative to ‘BR06’, and column 3 shows the qualitative descriptor for mushroom strain ‘BR06’ relative to ‘RO10425’.

TABLE 12A
Characteristic	‘RO10425’	‘BR06’
First Break
Cap L* Value (dark-light)	Lighter	Darker
Cap a* Value (green-red)	Greener	Redder
Cap b* Value (blue-yellow)	Bluer	Yellower
Cap Apex Flesh Thickness	Thicker	Thinner
Cap Edge Flesh Thickness	Thicker	Thinner
Cap Roundness (Calculated)	Rounder	Flatter
Second Break
Cap L* Value (dark-light)	Lighter	Darker
Cap a* Value (green-red)	Greener	Redder
Cap b* Value (blue-yellow)	Bluer	Yellower
Cap Apex Flesh Thickness	Thicker	Thinner
Cap Edge Flesh Thickness	Thicker	Thinner
Cap Roundness (Calculated)	Rounder	Flatter

Table 12B shows additional quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘BR06’. Column 1 shows each trait and the strains compared for said trait, column 2 shows the mean value for that strain's measurements of that trait, column 3 shows the median value of the same measurements, column 4 shows the interquartile range (“IQR”) for the same measurements, column 5 shows the number of trials conducted, and column 6 shows the statistical significance group calculated for that strain for that trait according to Dunn's Test.

TABLE 12B
				Number	Signifi-
				of	cance
				Mush-	Group
				rooms	(Dunn's
Variety	Mean	Median	IQR	(n)	Test)
First Break
Cap L* Value (dark-light)
‘RO10425’	65.66	65.22	7.34	209	a
‘BR06’	63.30	62.74	9.83	797	b
Cap a* Value (green-red)
‘RO10425’	7.35	7.43	1.97	209	a
‘BR06’	8.67	8.96	2.58	787	b
Cap b* Value (blue-yellow)
‘RO10425’	28.43	28.58	3.10	209	a
‘BR06’	28.72	29.04	3.17	776	b
Cap Apex Flesh Thickness
‘RO10425’	0.55	0.55	0.04	166	a
‘BR06’	0.52	0.52	0.05	541	b
Cap Edge Flesh Thickness
‘RO10425’	0.30	0.31	0.05	166	a
‘BR06’	0.21	0.21	0.09	537	b
Cap Roundness (Calculated)
‘RO10425’	0.64	0.63	0.05	166	a
‘BR06’	0.61	0.61	0.04	541	b
Second Break
Cap L* Value (dark-light)
‘RO10425’	68.82	69.47	8.20	157	a
‘BR06’	65.68	65.49	5.90	340	b
Cap a* Value (green-red)
‘RO10425’	6.15	6.26	2.55	157	a
‘BR06’	7.21	7.31	2.42	340	b
Cap b* Value (blue-yellow)
‘RO10425’	27.69	27.46	2.54	157	a
‘BR06’	28.15	28.49	2.86	340	b
Cap Apex Flesh Thickness
‘RO10425’	0.55	0.55	0.04	157	a
‘BR06’	0.51	0.52	0.07	362	b
Cap Edge Flesh Thickness
‘RO10425’	0.32	0.32	0.05	157	a
‘BR06’	0.23	0.23	0.09	362	b
Cap Roundness (Calculated)
‘RO10425’	0.61	0.61	0.05	157	a
‘BR06’	0.60	0.59	0.06	363	b

Table 13A below provides qualitative comparisons between mushroom strain ‘RO10425’ and strain ‘B14528’. Traits of interest are bolded in Tables 13A and 13B. Column 1 lists the individual mushroom-level characteristic (as described in Table 1), column 2 shows the qualitative descriptor for the characteristic for mushroom strain ‘RO10425’ relative to ‘B14528’, and column 3 shows the qualitative descriptor for mushroom strain ‘B14528’ relative to ‘RO10425’.

TABLE 13A
Characteristic	‘RO10425’	‘B14528’
First Break
Cap L* Value (dark-light)	Lighter	Darker
Cap a* Value (green-red)	Greener	Redder
Cap b* Value (blue-yellow)	Bluer	Yellower
Cap Apex Flesh Thickness	Thicker	Thinner
Cap Edge Flesh Thickness	Thicker	Thinner
Cap Roundness (Calculated)	Rounder	Flatter
Second Break
Cap L* Value (dark-light)	Similar	Similar
Cap a* Value (green-red)	Similar	Similar
Cap b* Value (blue-yellow)	Similar	Similar
Cap Apex Flesh Thickness	Thicker	Thinner
Cap Edge Flesh Thickness	Thicker	Thinner
Cap Roundness (Calculated)	Rounder	Flatter

Table 13B below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘B14528’, which resulted in the qualitative descriptors of Table 13A. Column 1 shows each individual mushroom-level trait (as described in Table 1) and the strains compared for said trait, column 2 shows the mean value for that strain's measurements of that trait, column 3 shows the median value of the same measurements, column 4 shows the interquartile range (“IQR”) for the same measurements, column 5 shows the number of mushrooms assessed (n), and column 6 shows the statistical significance group calculated for that strain for that trait according to Dunn's Test.

TABLE 13B
				Number	Signifi-
				of	cance
				Mush-	Group
				rooms	(Dunn's
Variety	Mean	Median	IQR	(n)	Test)
First Break
Cap L* Value (dark-light)
‘RO10425’	65.66	65.22	7.34	209	a
‘B14528’	64.06	64.13	6.56	340	c
Cap a* Value (green-red)
‘RO10425’	7.35	7.43	1.97	209	a
‘B14528’	8.26	8.31	2.13	340	c
Cap b* Value (blue-yellow)
‘RO10425’	28.43	28.58	3.10	209	a
‘B14528’	30.31	30.16	3.39	340	c
Cap Apex Flesh Thickness
‘RO10425’	0.55	0.55	0.04	166	a
‘B14528’	0.47	0.46	0.06	387	c
Cap Edge Flesh Thickness
‘RO10425’	0.30	0.31	0.05	166	a
‘B14528’	0.22	0.22	0.08	387	b
Cap Roundness (Calculated)
‘RO10425’	0.64	0.63	0.05	166	a
‘B14528’	0.61	0.61	0.05	389	b
Second Break
Cap L* Value (dark-light)
‘RO10425’	68.82	69.47	8.20	157	a
‘B14528’	68.56	69.02	6.54	170	a
Cap a* Value (green-red)
‘RO10425’	6.15	6.26	2.55	157	a
‘B14528’	6.09	5.96	2.05	170	a
Cap b* Value (blue-yellow)
‘RO10425’	27.69	27.46	2.54	157	a
‘B14528’	27.37	27.78	3.22	170	a
Cap Apex Flesh Thickness
‘RO10425’	0.55	0.55	0.04	157	a
‘B14528’	0.46	0.46	0.05	198	c
Cap Edge Flesh Thickness
‘RO10425’	0.32	0.32	0.05	157	a
‘B14528’	0.23	0.23	0.06	198	b
Cap Roundness (Calculated)
‘RO10425’	0.61	0.61	0.05	157	a
‘B14528’	0.60	0.60	0.05	198	b

As conducted in initial trials, comparisons were made between instant strain ‘RO10425’ and related strain ‘RO14176’. Tables 14A below provides qualitative comparisons between mushroom strain ‘RO10425’ and strain ‘RO14176’. Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the qualitative descriptor for the characteristic for mushroom strain ‘RO10425’ relative to ‘RO14176’, and column 3 shows the qualitative descriptor for mushroom strain ‘RO14176’ relative to ‘RO10425’.

TABLE 14A
Characteristic	‘RO10425’	‘RO14176’
First Break
Cap L* Value (dark-light)	Darker	Lighter
Cap a* Value (green-red)	Redder	Greener
Cap b* Value (blue-yellow)	Similar	Similar
Cap Diameter	Similar	Similar
Cap Height	Similar	Similar
Cap Flesh Thickness	Similar	Similar
Stipe Diameter	Larger	Smaller
Relative Cap Height	Similar	Similar
Relative Cap Flesh	Similar	Similar
Thickness
Relative Stipe Diameter	Larger	Smaller
Second Break
Cap L* Value (dark-light)	Similar	Similar
Cap a* Value (green-red)	Similar	Similar
Cap b* Value (blue-yellow)	Similar	Similar
Cap Diameter	Similar	Similar
Cap Height	Similar	Similar
Cap Flesh Thickness	Similar	Similar
Stipe Diameter	Larger	Smaller
Relative Cap Height	Similar	Similar
Relative Cap Flesh	Similar	Similar
Thickness
Relative Stipe Diameter	Larger	Smaller

Table 14B below provides quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘RO14176’ that informed the qualitative comparisons of Table 14A. In Table 14B, Column 1 lists the mushroom-level characteristics (as described in Table 1), column 2 shows the average value of the characteristic for mushroom strain ‘RO10425’, column 3 shows the standard deviation of the characteristic for mushroom strain ‘RO10425’, column 4 shows the average value of the characteristic for mushroom strain ‘RO14176’, column 5 shows the standard deviation of the characteristic for mushroom strain ‘RO14176’, and column 6 shows the p-values of two-sample, two-sided t-tests. Bolded p-values indicate p<0.05.

TABLE 14B
	‘RO10425’	‘RO14176’
		St.		St.
Characteristic	Average	Dev.	Average	Dev.	p-value
First Break
Cap L* Value	65.17	5.27	66.97	4.84	1.18E−05
(dark-light)
Cap a* Value	7.55	1.68	6.89	1.63	6.95E−07
(green-red)
Cap b* Value	28.52	2.09	28.46	2.07	6.92E−01
(blue-yellow)
Cap Diameter	43.18	3.81	43.25	3.94	8.21E−01
Cap Height	27.67	2.65	27.87	2.19	3.44E−01
Cap Flesh Thickness	15.26	1.61	15.19	1.73	6.44E−01
Stipe Diameter	21.66	2.08	19.92	2.43	1.94E−06
Relative Cap Height	0.65	0.04	0.65	0.04	3.41E−01
Relative Cap Flesh	0.35	0.03	0.35	0.05	1.66E−01
Thickness
Relative Stipe	0.50	0.04	0.45	0.05	1.50E−09
Diameter
Second Break
Cap L* Value	68.82	5.25	69.32	4.59	3.11E−01
(dark-light)
Cap a* Value	6.15	1.63	6.02	1.64	4.26E−01
(green-red)
Cap b* Value	27.69	1.91	27.50	2.11	3.19E−01
(blue-yellow)
Cap Diameter	43.19	4.08	42.56	3.62	1.08E−01
Cap Height	26.65	2.49	26.28	2.29	1.31E−01
Cap Flesh Thickness	14.51	1.34	14.24	1.60	6.04E−02
Stipe Diameter	20.90	2.02	17.80	2.58	4.81E−11
Relative Cap Height	0.62	0.04	0.62	0.05	3.57E−01
Relative Cap Flesh	0.34	0.03	0.34	0.04	9.52E−01
Thickness
Relative Stipe	0.46	0.04	0.42	0.05	1.84E−06
Diameter

One of the advantages of the strain ‘RO10425’ is its incompatibility with other commercial strains. Table 15 below provides results of compatibility tests between strain ‘RO10425’ and commercial strain ‘BR06’, commercial strain ‘B14528’, related strain ‘RO12756’ (U.S. application Ser. No. 19/305,683), and related strain ‘RO14176’. These results indicate that strain ‘RO10425’ is incompatible with strain ‘BR06’, strain ‘B14528’, and related strain ‘RO12756’, while strain ‘RO10425’ is compatible with related strain ‘RO14176’. This was true regardless of which tested strain served as the compost variety and which tested strain served as the casing variety.

	TABLE 15
	Strains
	(compost variety/	Mean	Median
	casing variety)	lb/ft2	kg/m2	lb/ft2	kg/m2
	RO10425'/'RO10425'	2.71	13.23	2.86	13.94
	RO12756'/'RO12756'	2.62	12.79	2.61	12.74
	RO14176'/'RO14176'	2.66	12.99	2.41	11.77
	BR06'/'BR06'	2.62	12.79	2.46	11.99
	B14528'/'B14528'	2.93	14.31	2.92	14.23
	RO10425'/'RO14176',	2.43	11.86	2.75	13.40
	'RO14176'/'RO10425'
	RO10425'/'B14528',	0.71	3.47	0.65	3.15
	'B14528'/'RO10425'
	RO12756'/'RO10425',	0.91	4.44	1.04	5.08
	'RO10425'/'RO12756'
	RO10425'/'BR06',	0.80	3.91	0.92	4.47
	'BR06'/'RO10425'
	Strains				Signi-
	(compost variety/	SD		ficance
	casing variety)	lb/ft2	kg/m2	Trials	Group
	RO10425'/'RO10425'	0.50	2.44	3	a
	RO12756'/'RO12756'	0.41	2.00	3	a
	RO14176'/'RO14176'	0.61	2.98	3	a
	BR06'/'BR06'	1.15	5.61	2	a
	B14528'/'B14528'	0.34	1.66	1	a
	RO10425'/'RO14176',	0.77	3.76	1	a
	'RO14176'/'RO10425'
	RO10425'/'B14528',	0.17	0.83	1	b
	'B14528'/'RO10425'
	RO12756'/'RO10425',	0.35	1.71	1	b
	'RO10425'/'RO12756'
	RO10425'/'BR06',	0.51	2.49	1	b
	'BR06'/'RO10425'

Table 16 below shows quantitative comparisons between mushroom strain ‘RO10425’ and strain ‘RO12756’. Column 1 shows each trait and the strains compared for said trait, column 2 shows the mean value for that strain's measurements of that trait, column 3 shows the median value of the characteristic, column 4 shows the interquartile range (IQR) for the characteristic, column 5 shows the number of mushrooms assessed (n), and column 6 shows the statistical significance group calculated according to Dunn's Test.

TABLE 16
				Number	Signifi-
				of	cance
				Mush-	Group
				rooms	(Dunn's
Variety	Mean	Median	IQR	(n)	Test)
First Break
Cap L* Value (dark-light)
‘RO10425’	65.66	65.22	7.34	209	a
‘RO12756’	72.12	72.29	4.81	580	b
Cap a* Value (green-red)
‘RO10425’	7.35	7.43	1.97	209	a
‘RO12756’	5.62	5.66	1.88	580	b
Cap b* Value (blue-yellow)
‘RO10425’	28.43	28.58	3.1	209	a
‘RO12756’	26.98	27.06	4.11	580	b
Cap Apex Flesh Thickness
‘RO10425’	0.55	0.55	0.04	166	a
‘RO12756’	0.55	0.55	0.06	575	a
Cap Edge Flesh Thickness
‘RO10425’	0.30	0.31	0.05	166	a
‘RO12756’	0.22	0.23	0.10	569	b
Cap Roundness (Calculated)
‘RO10425’	0.64	0.63	0.05	166	a
‘RO12756’	0.61	0.61	0.04	579	b
Second Break
Cap L* Value (dark-light)
‘RO10425’	68.82	69.47	8.20	157	a
‘RO12756’	73.02	72.87	4.35	200	b
Cap a* Value (green-red)
‘RO10425’	6.15	6.26	2.55	157	a
‘RO12756’	4.84	4.95	1.64	200	b
Cap b* Value (blue-yellow)
‘RO10425’	27.69	27.46	2.54	157	a
‘RO12756’	26.55	26.83	3.24	200	b
Cap Apex Flesh Thickness
‘RO10425’	0.55	0.55	0.04	157	a
‘RO12756’	0.54	0.54	0.04	198	a
Cap Edge Flesh Thickness
‘RO10425’	0.32	0.32	0.05	157	a
‘RO12756’	0.27	0.27	0.10	199	b
Cap Roundness (Calculated)
‘RO10425’	0.61	0.61	0.05	157	a
‘RO12756’	0.56	0.56	0.05	199	b

Claims

1. A new and distinct variety of Agaricus bisporus Imbach mushroom named ‘RO10425’. as shown and described herein.