METHOD FOR STIMULATING PLANT DISEASE SUPPRESSIVE ACTIVITY IN SPHAGNUM MOSS, RELATED PRODUCTS AND USES

Abstract

A method for stimulating plant disease-suppressive activity, such as soiland seed-borne fungal diseasesand saprophytic molds-suppressive activity, in Sphagnum moss biomass is provided. In the method freshly harvested and/or air-dried Sphagnum biomass is heat treated, thereupon a flow of air heated to a temperature within a range of 50-80 C. is conveyed thereto during a predetermined period of time. Sphagnum biomass is preferably selected from naturally occurring Sphagnum species, in particular, Sphagnum fuscum. A plant disease-suppressive growing medium and uses thereof are further provided.

Claims

1. A method for stimulating plant disease-suppressive activity in Sphagnum moss biomass, wherein in said method Sphagnum moss biomass is heat treated, thereupon a flow of air heated to a temperature within a range of 50-80 C. is conveyed to Sphagnum moss biomass during a predetermined period of time.

2. The method of claim 1, wherein said Sphagnum moss biomass is freshly harvested and/or allowed to air-dry at a temperature less than 50 C. prior to heat treatment.

3. The method of claims 1, wherein the time period for heat treatment of Sphagnum moss biomass is 0.01-24 hours.

4. The method of claim 1, further comprising subjecting Sphagnum moss biomass to size reduction prior to heat treatment, thereupon a fibrous particulate with particle size at most 40 mm is formed.

5. The method of claim 1, further comprising classifying the heat treated fibrous particulate by particle size thereof to form a number of fractions with particle size distribution within any one of the: 2-4 mm, 4-8 mm, 8-20 and 20-40 mm.

6. The method of claim 1, further comprising subjecting heat treated Sphagnum moss biomass to size reduction, thereupon a powder with particle size distribution within 0.1-2 mm is formed.

7. The method of claim 1, wherein Sphagnum moss biomass is selected from naturally occurring Sphagnum species and naturally occurring mixed Sphagnum moss community blends.

8. The method of claim 1, wherein Sphagnum moss biomass essentially consists of Sphagnum fuscum.

9. The method of claim 1, wherein Sphagnum moss biomass essentially consists of vegetative parts of Sphagnum moss plants occurring at a depth between about 30 cm and about 10 cm.

10. The method of claim 1, wherein plant disease-suppressive activity is at least soil-borne- and seed-borne fungal disease-suppressive activity and saprophytic mould-suppressive activity.

11. A plant disease-suppressive growing medium comprising Sphagnum moss biomass stimulated according to the method defined in claim 1, wherein said plant disease-suppressive growing medium is provided in the form of a fibrous particulate or a powder with particle size at most 40 mm.

12. The plant disease-suppressive growing medium of claim 11 in the form of a fibrous particulate having particle size distribution selected from the group consisting of: 2-4 mm, 4-8 mm, 8-20 mm and 20-40 mm.

13. The plant disease-suppressive growing medium of claim 11 in the form of a powder with particle size distribution 0.1-2 mm.

14. The plant disease-suppressive growing medium of claim 11, comprising Sphagnum moss biomass selected from naturally occurring Sphagnum species and naturally occurring mixed Sphagnum moss community blends.

15. The plant disease-suppressive growing medium of claim 11, comprising Sphagnum moss biomass that essentially consists of Sphagnum fuscum.

16. The plant disease-suppressive growing medium of claim 11, further comprising an at least one additive selected from the group consisting of: nutrients, fertilizers, biochar, bio-ash, peat, bark, sawdust, clay, perlite, binders, surfactants, or any combination thereof.

17. A seedbed comprising the plant disease-suppressive growing medium as defined in claim 11.

18. A fungus-, mold- and/or mildew prevention agent comprising the plant disease-suppressive growing medium according to claim 11.

19. An insulating material comprising the plant disease-suppressive growing medium according to claim 11.

20. The method of claim 2, wherein the time period for heat treatment of Sphagnum moss biomass is 0.01-24 hours.

Description

EXAMPLES

[0087] The examples presented hereinbelow are understood to be illustrative of various embodiments of the present invention and not restrictive thereof and are non-limiting with respect to the scope of the invention.

[0088] Trials were conducted using as a feedstock naturally occurring mixed Sphagnum moss community blends, further referred to as Sphagnum biomass, collected in Parkano area, Finland. Sphagnum biomass feedstocks were allowed to air-dry and size-reduced to form particulate fractions with particle size at most 40 mm, and particulate fractions with particle size at most 20 mm. Air-drying (pre-drying) is applicable for all examples, unless explicitly stated otherwise. Moisture content of the size-reduced Sphagnum biomass was adjusted to reach field capacity value (75 vol-%) and/or irrigation threshold (35 vol-%), as describe in Example 8.

[0089] Heat treatment according to the method of the invention was conducted in a heating oven with a function of continuous air supply. Moisture content of a heat treated product (growing medium) was further adjusted to reach field capacity value (75 vol-%) for assessing fungistatic activity (Example 6). Heat treated growing media were further supplied with dolomite lime (4 g) and peat-derived fertilizes (2 g), as provided per IL of the growing media (Example 2.2). Specific weight of said growing medium constituted 35-40 g/L, unless otherwise provided.

[0090] Post-treatment cultivation- and moulding trials were conducted in a greenhouse facility at about 20 C. in conditions of constant relative humidity (about 70%). Aforesaid temperature and humidity related parameters are applicable to all examples citing the greenhouse facility.

[0091] In all examples air-dried (not heat treated) Sphagnum biomass was used as a positive control.

Example 1

Mould Development on a Peat-Derived Growth Substrate and the same Supplied with Air-Dried Sphagnum Biomass (Positive Control)

[0092] Procedure: Air-dried Sphagnum biomass (positive control) with particle size about 20 mm was admixed to a peat-derived growth substrate (Grow Board by Kekkil; specific weight about 100 g/L) in proportions 0, 10, 25, 50 and 100 vol-%. Cultivation pots containing aforesaid batches were maintained sufficiently moist over the duration of trials. In the beginning of trials cinnamon mould (Chromelosporium fulvum; peat mould) was transferred into each pot from elsewhere.

[0093] Result: In the pots containing Sphagnum biomass in an amount of 50 vol-%, formation of mould was completely prevented; whereas in the pots containing the same in an amount of 25 vol-%, mould growth was markedly reduced. Pots containing only Sphagnum biomass (100 vol-%) developed no mould.

Example 2

Investigating Damping-Off Disease Caused by Alternaria in Cauliflower Seedlings

Example 2.1

Investigating Plant Disease-Suppressive Activity Effect of Air-Dried Sphagnum Biomass (Positive Control) in Disinfected Peat

[0094] Procedure: Cauliflower seeds were infected by Alternaria brassicicola followed by planting said seeds into a growth substrate containing autoclave-disinfected (corresponds to conventional 1 hour steaming) peat and air-dried Sphagnum biomass with particle size about 20 mm (positive control) in proportions 0, 10, 25, 50 ja 100%. Seeds were infected by dipping into A. brassicicola aqueous suspension (1 PDA (Potato Dextrose Agar) plate/100 ml water).

[0095] Result: In concentrations 10 to 50 vol-%, and 100 vol-% Sphagnum biomass markedly reduced the symptoms caused by damping-off disease (Table 1), Trials conducted for 4 batches each containing 25 seeds.

TABLE-US-00001 TABLE 1 Plant disease-suppressive activity effect of air-dried Sphagnum biomass admixed into disinfected peat in proportions 0, 10, 25, 50 ja 100%. Disease rate: 0 = healthy, 2 = strong deterioration/number of plants Peat %/Sphagnum Damping-off, Alive/100 biomass % 0 1 2 % seeds 100/00 7 18 14 46 39 90/10 34 23 15 25 72 75/25 16 15 17 41 48 50/50 36 24 11 18 71 00/100 50 17 8 13 75 Healthy seeds in 95 0 0 2 95 peat

Example 2.2

Investigating Plant Disease-Suppressive Activity Effect of Sphagnum Biomass Heat Treated According to One Aspect of the Invention, With Regard to Alternaria-Caused Diseases

[0096] Procedure: Sphagnum biomass feedstock was allowed to air-dry in a greenhouse facility at about 20 C., followed by size-reduction to form particulate fractions with particle size about 20 mm. Moisture content of size-reduced feedstock was adjusted to reach field capacity value (75 vol-%). Heat treatment (heating oven, air supply) was conducted at 70 C. during 2 days. Cauliflower seeds, pre-infected by A. brassicicola as described in the Example 2.1 and further dried between filter paper sheets during 2 days, were planted into thus obtained growing medium. Results were compared to that obtained by planting both healthy and infected seed into air-dried Sphagnum biomass (positive control, see Example 2.1). In some trials Sphagnum biomass was further supplied, prior to heat treatment, with lime and fertilizer, or only by lime. In the other trials liming was performed after heat treatment.

[0097] Result: Heat treating Sphagnum biomass at 70 C. markedly improved plant disease-suppressive activity. In comparison with positive control (air-dried Sphagnum biomass), plant disease-suppressive activity of heat treated Sphagnum biomass preserved substantially unchanged (Tables 2, 3). Liming of Sphagnum biomass prior to heat treatment does not reduce disease-preventive activity as compared to positive control. Liming also appears to prohibit further increase in the disease-preventive activity during heat treatment executed at 70 C. (Table 3).

TABLE-US-00002 TABLE 2 Influence of heat treatment (70 C., 2 days) on a survival rate of cauliflower seedlings in comparison to positive control. Three repetitions/25 seeds each. Batch Post-germination 1 2 3 period Seedlings alive, % 10 days 56.0 49.3 97.3 2 weeks 56.0 52.0 97.3 3 weeks 53.3 48.0 97.3 Legend: 1. Positive control (A): air-dried Sphagnum biomass with particle size 20 mm + infected seed (C), PDA/100 ml. 2. Heat treated at 70 C. Sphagnum biomass (B) + infected seed (C), PDA/100 ml. 3. A + healthy seed.

TABLE-US-00003 TABLE 3 Effect imposed by time point of liming and fertilizing onto the plant disease-suppressive activity of Sphagnum biomass heat treated at 70 C. Four repetitions/16 seeds each. Batch Post-germination 1 2 3 4 5 period Seedlings alive, % 10 days 62.5 84.4 84.4 95.3 100.0 17 days 65.6 93.8 81.3 79.7 100.0 5 weeks 54.7 85.9 57.8 59.4 98.4 Legend: 1. Positive control: air-dried Sphagnum biomass with particle size 20 mm, liming and fertilizing are performed along with the moisture content adjustment + infected seed. 2. Heat treated at 70 C. Sphagnum biomass, liming and fertilizing are performed after heat treatment + infected seed. 3. Heat treated at 70 C. Sphagnum biomass, liming is performed before heat treatment and fertilizing is performed after heat treatment + infected seed. 4. Heat treated at 70 C. Sphagnum biomass, liming and fertilizing are performed before heat treatment + infected seed. 5. Positive control as in (1), liming and fertilizing are performed along with the moisture content adjustment + healthy seed.

Example 3

Mould Development in Air-Dried Sphagnum Biomass (Positive Control)

[0098] Procedure: Air-dried Sphagnum biomass (positive control) with particle size about 20 mm was placed into 50 mm cultivation cells that were kept in a greenhouse facility for 1 month. Mould development in samples has been examined three times by stereomicroscopic methods.

[0099] Result: No visible signs of mould development were observed during trials, Microscopic examination revealed presence of sparse mycelia occurring between Sphagnum particles, which mycelia did not form reproductive organs. Vegetative resides present in the examined Sphagnum samples and originating from hays and other Sphagnum -unrelated grasses were uncontaminated in the interior of the Sphagnum sample bulk. However, those vegetative resides located on the surface of said samples and forming no direct contact with Sphagnum particles had developed mould caused by Penicillium. Nevertheless, these fungi developed no growth populations into neighboring areas.

Example 4

Heat Treatment of Sphagnum Biomass in Web-Based Pots

[0100] Procedure: A number of 0.61. cultivation pots having a bottom/base made of web, each containing 3-4 dl of air-dried Sphagnum biomass, were prepared. Some pots contained Sphagnum biomass not subjected to size reduction; and some pots contained the same with particle size about 20 mm. Aforesaid pots were heat treated during 1 day and 2 days, at 40, 50, 60, ja 70 C. Each heat treatment was reproduced with 10 pots. After heat treatment the pots were kept in a greenhouse facility in conditions of daily moistening for 2 months. Prior to aforesaid incubation cinnamon mould was inoculated into all pots with inoculate obtained from moulds collected from the (moulded) commercial peat-derived growing substrates (Grow Board by Kekkil). Mould development in the Sphagnum batches was evaluated weekly.

[0101] Result: After expiration of the trial period (2 months) all heat treated batches were mould-free.

Example 5

Comparison of the Sphagnum Biomass Heat Treated at 70 C. in Presence and Absence of Air

[0102] Procedure: A number of 10 L containers were prepared with about 3L of Sphagnum biomass placed into each container. Containers of a first type had solid bottom and sidewalls made of web to enable air supply. Containers of a second type (e.g. buckets) had solid bottom and solid sidewalls; additionally, top openings thereof were sealed with a plastic film in order to preserve moist during treatment. Heat treatment was conducted at 70 C. (2 days), thereafter Sphagnum biomass was disposed into 50 mm cultivation cells and kept in conditions of a greenhouse facility.

[0103] Result: In Sphagnum biomass heat treated in the sealed containers prominent and uniformly grown mould caused by Penicillium was observed already after 3 days of incubation. Sphagnum biomass heat treated in the containers allowing for air circulation demonstrated slight signs of mould growth only after 1 month of incubation.

Example 6

Investigating Plant Disease-Suppressive Activity Effect of the Sphagnum Biomass Heat Treated According to One Aspect of the Invention, With Regard to Pythium-Caused Diseases

[0104] Procedure: Heat treatment at 70 C. (2 days) was conducted on a number of 3 L Sphagnum biomass batches (particle size 20 mm) as described in Example 5. Thereafter moisture content in the 10 L containers was adjusted to reach field capacity value (75 vol-%), followed by inoculating resulted growing media with Pythium ultimum known to cause damping-off and root-rot diseases in seedlings. From each container three 0.6 L cultivation pots were prepared and 5 cucumber seeds were planted into each pot, In some trials heat treated. growing media additionally contained oat flour (5 g/L) (Table 4).

[0105] Infected Sphagnum biomass-derived growing medium was further applied in a flange-like manner around recently emerged cucumber seedlings planted into peat-derived growing media containing pots (negative controls), optionally comprising oat flour (5 g/L) (Table 5).

[0106] Result: Cucumber seeds planted into Sphagnum biomass heat treated in an absence of air (in sealed containers) either failed to emerge or collapsed very soon after emergency (Table 4). In Sphagnum biomass heat treated in presence of air (containers with sidewalls made of web) significantly more seedlings emerged in comparison to the wet growing medium. In Sphagnum biomass heat treated at 70 C. in presence of air all seeds produced seedlings that preserved healthy for 1.5 weeks, thereafter a part of the seedlings fell over because of damping-off (Table 4).

[0107] In the growing medium comprising air-dried Sphagnum biomass (positive control) about a half of all seeds sprouted/produced seedlings that got infected soon after emergency at a very young age.

[0108] Infected Sphagnum biomass applied around seedlings that recently emerged in the pots containing heat treated peat-derived growing media (without oat flour) caused no disease. Addition of oat flour into heat treated Sphagnum biomass-derived growing media resulted in damping-off. However, the disease developed to a lowest extent in the batches heat treated at 70 C. (Table 5).

TABLE-US-00004 TABLE 4 Damping-off disease caused by Pythium in cucumber planted into growing media (particle size 20 mm) produced by heat treating Sphagnum biomass at 70 C. (2 days) and in peat-derived growing media. All growing media inoculated with Pythium 7 days before seeding. Batches comprise 0.6 L pots each planted with 5 cucumber seeds; 3 repetitions/batch. Numerical values refer to an average number of seedlings per batch. Observation dates 6.4.2014 8.4.2014 16.4.2014 Emerged Healthy Healthy Growing medium without oat flour Air-dried Sphagnum 2.0 0.0 0.0 (positive control) Heat treated Sphagnum, 5.0 5.0 2.0 70 C. Heat-treated peat, 70 C. 2.3 0.0 0.0 (negative control) Growing medium comprising oat flour 5 g/l Air-dried Sphagnum 0.0 0.0 0.0 (positive control) Heat treated Sphagnum, 0.0 0.0 0.0 70 C. Heat-treated peat, 70 C. 0.0 0.0 0.0 (negative control)

TABLE-US-00005 TABLE 5 Damping-off disease caused by Pythium in cucumber planted into growing media (particle size 20 mm) produced by heat treating Sphagnum biomass at 70 C. (2 days) and in peat-derived growing media. All growing media inoculated with Pythium 7 days before seeding. Inoculated growing medium applied on Apr. 1, 2014 around recently emerged seedlings grown on healthy peat-derived growing media. Batches comprise 0.6 L pots each planted with 10 cucumber seeds. Numerical values refer to a number of healthy seedlings per 10 pots. Observation dates 4.4.2014 5.4.2014 6.4.2014 8.4.2014 Growing medium without oat flour Air-dried Sphagnum 10 10 10 10 (positive control) Heat treated Sphagnum, 10 10 10 9 70 C. Heat-treated peat, 70 C. 10 10 10 10 (negative control) Growing medium comprising oat flour 5 g/l Air-dried Sphagnum 3 0 0 0 (positive control) Heat treated Sphagnum, 6 3 3 0 70 C. Heat-treated peat, 70 C. 3 0 0 0 (negative control)

Example 7

Plant Disease-Suppressive Growing Medium in the Form of a Powder

[0109] Procedure: Sphagnum biomass was placed into about 10 L containers having solid bottom and web-made sidewalls to enable air supply and heat treated at 70 C. for 2 days. After heat treatment the lowest layer of biomass in the container seemed to preserve some moist. Heat treated Sphagnum biomass was size-reduced in a hammer mill followed by sieving to produce fine powder (with particle size distribution 0.1-2 mm). Two test runs were carried out as follows. In a first test run 5, 10 and 50 g of thus obtained powder were distributed along a surface of a peat-derived Grow Board by Kekkil(0.25 wt-%, 0.5 wt-% and 2.5 wt-% with regard to the amount of peat, accordingly). In a second test run the aforesaid commercial peat-derived board was disintegrated to form loose particulate and Sphagnum -derived powder was admixed thereto (1 g, 10 g and 100 g/kg). Resulted composites were moistened and placed into greenhouse facility conditions. Generation and growth of cinnamon mould were evaluated during one month time-period.

[0110] Result: Sphagnum biomass-derived powder distributed on or admixed to conventional growing media in the aforesaid amounts reduced generation of mould.

Example 8

Influence of Initial Moisture Content in the Sphagnum Biomass on Fungistatic Activity Thereof

[0111] Procedure: Moisture content in Sphagnum biomass was adjusted to reach the following values: 1. 15 vol-% (air-dry); 2. 35 vol-% (irrigation threshold; =50 cm: water potential); and 3. 75 vol-% (field capacity; 10 cm: water potential). Heat treatment was conducted thereafter at temperatures 50, 60, 70 and 80 C. in sealed containers and in containers with web-made sidewalls, as described in previous examples. After heat treatment the lowest layer of biomass in the container seemed to preserve sonic moist. Two test runs were carried out in accordance to what is described in Example 6 (Pythium test) and in Example 4 (cinnamon mould test); however, inoculation with cinnamon mould was performed by transferring a fingernail-sized transplant from a mouldy peat-derived growth substrate (Grow Board by Kekkil) onto Sphagnum biomass. Each test was conducted in three pots containing five cucumber seeds per pot. Three repetitions per each pot were made. At the end of trials fresh weight was determined for all seedlings.

[0112] Result: Pythium tests demonstrated differences in seedlings' emergency rates and subsequent occurrence of damping-off. Damping-off rate was the highest in Sphagnum biomass heat treated in sealed containers. The greatest emergency rate (100%) and the highest number of healthy seedlings/per pot (3.3) were observed in open containers heat treated at 70 C., whose initial moisture content constituted 35 vol-%. At 80 C. and with the same moisture content the number of seedlings/per pot was 1.4. In all trials Pythium-caused weakening in seedlings' growth was observed, as compared to the results obtained from the non-infected Sphagnum biomass-derived growing medium (positive control). See Tables 6 and 7.

TABLE-US-00006 TABLE 6 Development of mould, amount of cucumber seedlings and weight thereof observed in the Sphagnum biomass air-dried (positive control) and heat treated at different temperatures and in varying conditions of air supply. Surface Emerged Emerged moulding seedlings seedlings 0-5 g/seedling % Heat treatment Open container 1.25 4.74 89.86 Sealed container 2.31 4.31 81.70 Moisture content in the Sphagnum biomass before heat treatment 15 vol-% 1.08 4.63 87.92 35 vol-% 1.50 4.88 92.66 75 vol-% 1.17 4.69 89.00 Heat treatment, temperature 50 C. 0.56 4.70 89.15 60 C. 2.00 4.71 89.39 70 C. 1.44 4.73 89.82 80 C. 0.56 4.70 89.15 Air-dried Sphagnum 0.00 5.27 100 biomass (positive control)

TABLE-US-00007 TABLE 7 Evaluating amount, weight and health of recently emerged and two-week old cucumber seedlings planted in the growing media derived from the Sphagnum biomass at different temperatures and in varying conditions of air supply. Inoculation with Pythium performed after heat treatment, but one week before inserting seeds into growing media. Emerged Number and weight of regular seedlings seedlings Healthy seedlings/ seedlings/ treatment treatment g/test square g/plant Heat treatment Open container 3.36 2.75 9.33 3.31 Sealed container 2.67 2.31 6.94 2.72 Moisture content in the Sphagnum biomass before heat treatment 15 vol-% 3.08 2.33 7.08 3.06 35 vol-% 3.50 3.33 11.75 3.48 75 vol-% 3.50 2.58 9.17 3.39 Heat treatment, temperature 50 C. 1.78 1.44 4.56 3.11 60 C. 3.89 2.78 8.67 3.10 70 C. 3.67 3.33 12.22 3.62 80 C. 1.78 1.44 4.56 3.11 Air-dried Sphagnum 5.00 5.00 26.33 5.27 biomass (positive control)

Example 9

Investigating Plant Disease-Suppressive Activity Effect of the Air-Dried Sphagnum Biomass Heat Treated at Temperatures 40-80 C.

[0113] Trials in cucumber: Heat treatment at temperatures 40, 50, 60, 70 and 80 C. was conducted on air-dried Sphagnum biomass batches (moisture content 10-15 vol-%) during 12 hours. Heat treated Sphagnum batches were subjected to moistening, liming and fertilization, followed by inoculation with an aqueous suspension of Pythium ultimum 7 days before seeding (40 g of Sphagnum biomass per a 9 cm PDA plate). White horticultural peat substrate was used as a healthy control. The same peat substrate inoculated P. ultimum and disinfected during 12 hours at 80 C. (1 L of peat substrate per batch) was used as an infected control, Sphagnum biomass was kept in conditions of a greenhouse facility at 20 C. and daylight duration 12 hours.

[0114] Trials in cauliflower: Heat treatment conditions and utilized growing media were the same as described above. Cauliflower seeds were inoculated with an aqueous suspension of Alternaria brassicicola (1 PDA plate/100 ml water). Each test square comprised 14 seedling trays (5 cm) each containing 0.5 dl of growing medium.

[0115] Result: For cucumber, all seeds in the healthy control emerged and remained healthy until expiration of the trials (see Table 8), On the contrary, no germination occurred in the infected control. All heat treated Sphagnum batches contained seedlings, a part of which remained alive until expiration of trials. Sphagnum batches heat treated at 60 C. contained significantly more seedlings of considerably greater size.

[0116] For cauliflower, the infected control contained significantly less seedlings eligible for planting, as compared to the heat treated Sphagnum batches. The most lightweight seedlings were observed in the Sphagnum batches treated at 80 C. (see Table 9).

TABLE-US-00008 TABLE 8 Amount, fresh weight and root morbidity of cucumber seedlings observed in the Sphagnum biomass air-dried and heat treated at various temperatures during 12 hours. All growing media inoculated with Pythium ultimum 7 days before seeding. Trial duration was 25 days. Root Germinated, Plants alive at the morbidity number/test end of the trials, Fresh weight, rate 0-3/ Batch square number/test square g/test square test square 0 5.0 5.0 50.1 0.0 1 0.0 0.0 0.0 3.0 2 2.5 1.5 9.4 1.7 3 3.5 2.3 16.8 1.0 4 3.8 3.2 25.6 1.0 5 2.2 1.5 11.8 1.3 6 2.2 1.2 9.5 1.7 Legend (batches): 0. Peat, healthy control. 1. Peat, infected control. 2. Sphagnum, 40 C. 3. Sphagnum, 50 C. 4. Sphagnum, 60 C. 5. Sphagnum, 70 C. 6. Sphagnum. 80 C. Each batch contained 6 repetitions and each test square contained 5 seeds.

TABLE-US-00009 TABLE 9 Amount of cauliflower seedlings eligible for planting and an average fresh weight thereof observed in Sphagnum biomass air-dried and heat treated at various temperatures during 12 hours. Seeds were inoculated with A. brassicicola. Trial duration was 26 days. Seedlings eligible for planting, Batch number/test square Average weight of a seedling, g 0 13.4 3.17 1 8.0 3.03 2 11.2 2.89 3 11.0 3.07 4 12.2 3.00 5 11.0 2.81 6 11.4 2.60 Legend (batches): 0. Peat, healthy control. 1. Peat, infected control. 2. Sphagnum, 40 C. 3. Sphagnum, 50 C. 4. Sphagnum, 60 C. 5. Sphagnum, 70 C. 6. Sphagnum, 80 C. Each batch contained 5 repetitions and each test square contained 14 seeds (in 5 cm seedling trays).