Fumigant Use for Strawberry Production in Europe: The Current Landscape and Solutions

ABSTRACT

The impact of methyl bromide (MB) phase-out on important fruit and nursery industries in the EU (2005/2008) has been significant. Under EU Regulation 1107/2009, MB fumigant alternatives 1,3-dichloropropene and chloropicrin were also phased out (in 2010 and 2013, respectively) while dazomet, metam sodium, and potassium were re-approved with crucial restrictions of rates and years of application. However, currently an EU Member State may authorize use of these phased-out fumigants for 120 days/year. This exemption has been used for strawberry (fruit and nursery production) and other crops in Spain, Italy, Belgium, France, UK, Cyprus, Malta, and Greece in recent years. To provide an update of the current situation, a comprehensive survey of 41 European and other industries has been completed. Most of them use crop rotation as the main pest management solution. Non-chemical solutions, in particular soilless cultivation, are important in the UK, Ireland, France, the Netherlands, and Belgium. Chemical fumigation is still important in Spain, Italy, Morocco, Turkey, France, and Belgium.

KEYWORDS:

• Fragaria × ananassa
• soil disinfestation
• fruit and nursery production
• crop rotation
• non-chemical
• soilless
• chemical
• metam sodium
• dazomet
• 1,3-dichloropropene
• chloropicrin

Introduction

In the European Union (EU) soil fumigation represents a main component of soil pest management for many horticultural crops, in particular those grown in monoculture in Southern Mediterranean countries. In general, the use of agrochemicals in intensive agriculture has decreased more than 30% due to the agro-environmental EU policies and public opinion pressure. The EU regulations are increasingly limiting use of pesticides and chemical fumigants, stimulating industries to face new challenges. The availability of chemical methyl bromide (MB) alternatives in the near future is unclear (López-Aranda, 2013). In fact, the intensive agriculture in the EU has suffered two simultaneous restrictions: (a) MB phase out and, immediately after, (b) exclusion of the most important chemical alternatives: 1,3-dichloropropene (1,3D) and chloropicrin (CP) from the list of available chemical fumigants. MB was phased out in the EU by 2008, after the compromise with the Montreal Protocol (MP) according to the Regulation (EC) 2037/2000 on substances that deplete the ozone layer for soil and structural uses and 1,3D and CP according to Regulation (EC) 1107/2009 focused on the placement of plant protection products on the market. These EU fumigant regulations emphasized the greater importance of human health and environmental protection compared to the needs of crop protection. The phase-out of MB was unanimously accepted by all of the EU Member States and strawberry industries. However, the non-approval of 1,3D and chloropicrin was a clear political decision of the qualified majority of the EU countries. The vote of the EU Standing Committee on the Food Chain and Animal Health resulted in 154 votes supporting, 150 against, and 41 abstaining in the 1,3D case in 2010; and 92 votes supporting, 248 against, and 12 abstaining in the CP case in 2013. Currently, the only available soil fumigants within the EU areas are as follows: 1,3D, 1,3D (cis), and CP, following the conclusions of pesticide peer review of the European Food Safety Authority (EFSA); i.e., for 1,3D, EFSA (2009); and for CP, EFSA (2011a). Dazomet, metam sodium (MS), and metam potassium (MK) were approved, following the conclusions of EFSA (2010) for dazomet and EFSA (2011b) for metam. The decision about dimethyl disulphide (DMDS, Paladin) is pending after dossier of the “notifier” (owner of the molecule) was submitted in 2012. Dazomet and MS and MK are approved for use in EU, but with some important restrictions. Application is limited to one per 3 years in the same field with a maximum rate of 490 kg/ha for dazomet and 153 kg/ha for metam (Commission implementing Directive 2011/53/EU of 20 Apr. 2011 and Commission implementing Regulation (EU) No. 540/2011 of 25 May 2011 for dazomet; Commission implementing Regulation (EU) No. 359/2012 of 25 Apr. 2012 for metam). The maximum application rate for dazomet is likely sufficient for growers and nurserymen. However, for metam, this rate (equivalent to 300–380 l/ha of commercial product formulation) is substantially lower than current use rates ranging between 500 to 1200 l/ha. This requires judicious utilization of metam (MS and/or MK) and dazomet by the strawberry industry in the EU and presents new challenges in more efficient utilization of available fumigants, such as: for maintaining efficacy with lower product rates, development of new application technologies (e.g., Spading and Mix-Tiller implements), and seasonal rotation of fumigant types.

Based on current global fumigant use patterns, it is likely that EU-SANCO/EFSA and USA-EPA, the two largest agencies regulating agrochemical use in the Western World, will develop similar processes for approval of fumigants, rates and restrictions of application in the near future. However, community and regional regulations and agricultural industry needs may be very different in several EU countries. Member States can allow temporary National emergency uses (120 days per year) of fumigants for particular agricultural industries (sectors. These authorizations allowed for use of 1,3D since 2009 and for CP since 2014. The derogation for National emergency uses has been widely applied to many chemical compounds and sectors in several EU countries. For instance, in 2014, Belgium, Cyprus, France, Italy, Spain, and the United Kingdom granted authorizations for commercial use of 1,3D and/or CP fumigants for their strawberry industries. However, the future of these limited authorizations for 1,3D and CP is very unclear even in the short term. For this reason, the owners of both products have presented new requests for re-approval (De Luna and Piardi, personal communication). In general, the transition from MB to alternative fumigants has been gradual and at a pace acceptable to the affected industries. However, increasingly severe restrictions and potential loss of soil fumigants are of great concern in several countries.

Many soil disinfestation projects for strawberry and other crops in Europe have been presented, such as: Ajwa et al. (2003), Runia et al. (2007), and López-Aranda (2014), specifically for strawberry; and UNEP (2000), FAO (2007, 2008), Du Fretay et al. (2010), and Fritsch (2010), for several other crops in different countries.

Comprehensive survey

The aim of our work was to present the current landscape and solutions for soil disinfestation for the strawberry industry (fruit and nursery). A comprehensive survey of 41 European and other industries has been completed during the period of Oct. 2014 to Jan. 2015. Sources included: recent presentations, papers, reports, specialized workshops, and personal communications with strawberry experts in each European country (see Acknowledgements). The main objectives of this survey were to identify entities and locations of fruit and strawberry nursery industries, by country, and practices used for soil disinfestation (both chemical and non-chemical). The common soil management practices that appeared in the survey were: crop rotation, change of location, catch and cover crops, biofumigation, soil solarization, anaerobic soil disinfestation (ASD), soilless systems, as well as chemical fumigation with MS, MK, dazomet, 1,3D:CP, CP stand alone, and other methods. The acreage/hectarage of production with various disinfestation practices has also been recorded. This information has been used for evaluation using distribution methodology (Rosati, 1991) that groups European and connected regions.

Region 1: Mediterranean area (mild/Mediterranean climates; mild winters and hot summers)

Between parallel 30° and 42° N. Annual system of cultivation, under plastic tunnels, mainly for fresh market. The harvest period is from January to July. This Mediterranean basin below latitude 42° N includes the following countries and identified acreage (for fruit and nursery production): Cyprus (60 ha and 0 ha), Egypt (5800 ha and 100 ha), Greece (750 ha and 0 ha), Italy (South) (3717 ha and 400 ha for the whole country), Morocco (3600 ha and 0 ha), Portugal (543 ha and 25 ha), Spain (7300 ha and 1575 ha), and Turkey (5000 ha and 200 ha). A recent description of cultivar use in this region has been presented by López-Aranda et al. (2011).

Region 2: Central/Southern Europe (temperate/cool winters)

This region, above latitude 40/41° N has severe winters, with little snow cover, often resulting in strawberry plant crown injury. Consequently, production may fluctuate year to year. The harvest period is April to July. Late-season production is expanding. This region includes Albania (55 ha and 1 ha), Croatia (350 ha and 0 ha), France (3300 ha and 250 ha), Italy (North), and Switzerland (507 ha and 2 ha).

Region 3: Central/Northern Europe (continental/cold winters)

This region, above latitude 48° N relies on advanced production technology (particularly substrate production) and includes Belgium (1384 ha and 104 ha), Germany (14,700 ha and 150 ha), and the Netherlands (2100 ha and 1800 ha). Annual production prevails in Belgium and in the Netherlands. Waiting bed, tray, and A+ graded plants (plug plants) have been used mainly in the Netherlands for more than 50 years. In Germany, open fields are maintained for 1 or 2 years.

Region 4: Eastern Europe (continental/severe winters)

This region, above latitude 41/42° N also has very severe winters, with little snow cover, often resulting in strawberry plant crown injury. Traditional perennial culture systems are used. The matted row in open fields is the dominant production system, with increased transition to hill-row. The harvest period is May/June to August/September; late-season production is expanding. There are several EU and non-EU countries in this region: Austria (1300 ha and 0 ha), Belarus (6200 ha and 70 ha), Bosnia and Herzegovina (1200 ha and 5 ha), Bulgaria (633 ha and 0 ha), Czech Republic (500 ha and 17 ha), Hungary (450 ha and 10 ha), Kosovo (250 ha and 3 ha), Macedonia (800 ha and 1 ha), Moldova (247 ha and 0 ha), Poland (40000 ha and 500 ha), Romania (2082 ha and 150 ha), Serbia and Montenegro (7350 ha and 10 ha), Slovakia (600 ha and 0 ha), Slovenia (110 ha and 0 ha), and Ukraine (9200 ha and 60 ha). Region 7—Russian Federation, consists of a variable range of climatic zones above latitude 42° N (45,364 ha and 200 ha) but generally similar crop production systems to Region 4.

Region 5: Maritime climates/North-Western Europe

This region, above latitude 50° N has mild winters and differs from those North Eastern European countries at the same latitude (i.e., Scandinavian and Baltic countries). Traditional matted-row culture has been substituted by hill-row planting and greatly increased share of soilless production. The harvest period is June–September and late-season production is expanding. This region includes Ireland (225 ha and 10 ha) and United Kingdom (4850 ha and 70 ha).

Region 6: North/Eastern Europe (short growing season/severe winters)

This region (Scandinavian and Baltic countries), above latitude 54° N has very severe winters and, in general, relies on traditional perennial culture systems in open fields. The harvest period is between the end of June (South) to mid-August (North). It includes Denmark (1200 ha and 0 ha), Estonia (500 ha and 0 ha), Finland (3368 ha and 10 ha), Latvia (500 ha and 0 ha), Lithuania (400 ha and 15 ha), Norway (1513 ha and 12 ha), and Sweden (2100 ha and 5 ha).

A summary of the fruit production and nursery acreage in these regions is presented in Table 1. By acreage, the largest strawberry fruit production industries are: Russian Federation (45,364 ha), Poland (40,000 ha), Germany (14,700 ha), Ukraine (9200 ha), Serbia (7000 ha), Spain (7300 ha), Belarus (6200 ha), Egypt (5800 ha), Turkey (5000 ha), and the United Kingdom (4850 ha). However, in spite of this distribution of the acreage, the total production per year depends on the unitary yields that greatly differ among the Rosati’s Regions. Following the last updated EUROSTAT and FAOSTAT statistics, the averaged national yields of these important industries are: 41.54 t/ha (Egypt), 39.27 t/ha (Spain), 27.08 t/ha (Turkey), 19.20 (United Kingdom), 10.39 t/ha (Germany), 7.70 t/ha (Belarus), 7.14 t/ha (Ukraine), 6.44 t/ha (Russian F.), 4.00 t/ha (Serbia) (SIEPA), 3.55 t/ha to 5.00 t/ha (Poland) (EUROSTAT/Zurawicz, personal communication). Since soil disinfestation practices are applied to land areas, the survey results of chemical and non-chemical soil disinfestation methods are presented by acreage rather than by yield or total fruit production. The biggest nursery industries are: the Netherlands (1800 ha), Spain (1575 ha), Poland (500 ha), Italy (400 ha), France (250 ha), Turkey (200 ha), Russian F. (200 ha), and others. The Dutch and Spanish strawberry nurseries comprise about 60% of the total identified nursery acreage. An updated review of strawberry cultivars use and cultivation systems in Europe has been presented and discussed by Neri et al. (2012).

Table 1. Estimated acreage identified for European Rosati’s Regions.

	Hectares
Rosati’s Region	Fruit	Nursery	Main sources^z
1. Mediterranean	>26,770	~2,300	Author’s estimations, (1), (7), (13), (24), (31)
2. Central/South	>4,212	>253	(6), (12), (30)
3. Central/North	~18,184	>2,054	(4), (22)
4. & 7. East and Russia	~116,286	~1,026	(2), (3), (5), (8), (14), (19), (20), (23), (25), (26), (27), (28)
5. Western/North	>5,075	>80	(15), (33)
6. Nordic/Baltic	>9,581	<42	(9), (10), (11), (16), (17), (18), (21), (29)
Total	180,108	5,755

^zSee Acknowledgments, expert names in brackets.

Results

Entire fruit and nursery acreage

Our comprehensive survey of the whole strawberry fruit production (more than 180,100 ha) showed that 87% of the soil acreage is disinfested with non-chemical methods and 13% with chemical fumigants. Crop rotation and/or change of location as sole practices were used in 82.5% of the whole acreage, soilless cultivation systems in 3.4%, soil solarization in 1.3%, MS in 5.3%, 1,3D:CP in 4.6%, dazomet in 1.0%, and other management strategies (biofumigation, cover/catch crops, CP alone, and other chemicals) in 1.9%.

For the strawberry nurseries (more than 5755 ha identified), our survey showed that 32% of the whole acreage is fumigated with MS, 31% uses crop rotation and/or change of location only, 19.3% is fumigated with 1,3D:CP and/or 1,3D+CP, 8.6% relies on non-chemical methods (cover/catch crops, soil solarization, and ASD), 7.2% on fumigation with dazomet, and the rest (1.9%) on other chemical solutions.

Soil disinfestation practices

Crop rotation only for fruit and nursery production

Countries in Regions 4, 6, and 7 (East Europe, Scandinavian and Baltic countries, and Russian Federation) use crop rotation only as a tool for soil disinfestation. Between 95% and 100% of the total national acreage for fruit and nursery production relies on this practice in the Russian Federation, Poland, Ukraine, Serbia and Montenegro, Belarus, Finland, Sweden, Romania, Norway, Austria, and Denmark. The summary of crop rotation only for fruit and nursery production by country, acreage, and percentage of the total acreage is presented in Table 2.

Table 2. Estimated strawberry acreage utilizing crop rotation only (change of location included).

	Fruit production (ha)		Nursery production (ha)
Country	Acreage	% of total acreage	Acreage	% of total acreage	Main sources^z
Russia	45,364	100	200	100	(26)
Poland	39,200	98	0	0	(23)
Germany	14,490	98	130	87	Statistisches Bundesamt
Ukraine	9,200	100	60	100	(32)
Serbia and Montenegro	7,350	100	10	100	(27)
Belarus	6,200	100	70	100	(3)
Finland	3,368	100	10	100	(11)
Egypt	2,320	40	0	0	Author’s estimations
Sweden	2,058	98	5	100	(29)
France	2,050	62	0	0	(12), Agreste conjoncture
Turkey	1,750	35	0	0	(31)
Romania	1,520	73	0	0	(25)
Norway	1,498	99	12	100	(21)
United Kingdom	1,350	27	0	0	(33)
Austria	1,300	100	0	0	(2)
Denmark	1,140	95	0	0	(9)
Macedonia	800	100	1	100	(19)
Greece	745	99	0	0	(13)
Netherlands	700	33	0	0	(22), Eurostat
Bulgaria	633	100	0	0	(5)
Slovakia	600	100	No data	No data	Eurostat
Estonia	500	100	0	0	(10)
Latvia	500	100	0	0	(16), (17)
Czech Republic	500	100	17	100	(8)
Hungary	450	100	10	100	(14)
Switzerland	407	80	2	100	(30)
Lithuania	396	99	15	100	(18)
Italy	373	10	0	0	CSO, Ferrara
Croatia	345	98	0	0	(6)
Kosovo	250	100	3	100	(1)
Moldova	247	100	0	0	(20)
Slovenia	110	100	0	0	(28)
Bosnia and Herzegovina	110	100	5	100	Eurostat
Portugal	50	10	0	0	(24)
Ireland	11	5	10	100	(15)
Belgium	No data	No data	0	0	(4)
Cyprus	0	0	0	0	(7)
Albania	0	0	0	0	(1)
Morocco	0	0	0	0	Author’s estimations
Spain	0	0	0	0	Author’s estimations
Total	147,885		560

^zSee Acknowledgments, expert names in brackets.

The main practices include rotations with cereals, grasses, oilseed crops, legumes, and other crops as green manure, such as oil radish, mustards, winter rye, and buckwheat. For instance, in Poland, 98% of the total strawberry fruit acreage (40,000 ha) is planted in rotation with cereals, rapeseed, mustard, lupine, corn, and vegetable crops (beans, broccoli, or cabbage). In general, most of the new plantations are being established in fields with no previous history of strawberry cultivation and rely on use of certified or Conformitas Agraria Communitatis (CAC) plant material (EU category of pest and pathogen-free plants), controlled by the sanitary inspection. In the Czech Republic, crop rotation targets cultivation of strawberry once every 5 years and mainly cereals are grown during the other years. In Serbia and Montenegro and Macedonia, strawberry farms change planting locations continuously. In the North/Eastern European region, Germany relies most heavily on crop rotation with 98% of the total fruit acreage (14,700 ha) in rotation. Strawberry growers rotate within their own fields but also with other farmers of the nearby or even distant areas. Crop rotation for fruit production is also a very significant practice in Greece (99% of acreage), Croatia (98%), Switzerland (80%, with at least 3 years between strawberry crops), France (62%), and United Kingdom (27%). Among the main Southern industries (Region 1 Mediterranean area) crop rotation is used only in Egypt (40% of acreage) and Turkey (35%). In both cases only traditional systems of cultivation rely on crop rotation: in Egypt—old public varieties, frigo-plants, and open field bi-annual system, and, in Turkey—open field production in Central and Eastern Anatolian (high elevation) region where plantings are kept for perennial production.

Soil solarization for fruit production

Standard soil solarization is concentrated in several Southern countries. In Egypt 1150 ha and in Turkey more than 1000 ha (20% of total strawberry fruit production acreage) are solarized. Additionally, 250 ha in Sicily (Italy) and 30 ha in Cyprus (representing 50% of the total industry acreage in the country) use solarization. In Egypt, the large percentage of acreage under soil solarization is in governorates of Nile Delta (parallel 30/31° N), i.e., Kalubiya, Ismailiya, Sharkiya, Behira, and Menofiya, where solarization is conducted under tarps for 45 to 60 days from mid-June to end-August.

Catch/cover crops, biofumigation, and other non-chemical solutions for fruit and nursery production

The most important acreage that utilizes Tagetes patula is in the Netherlands. In this system, T. patula is grown as a catch/cover crop to control root lesion nematodes (Pratylenchus penetrans) and for green manure. This crop suppresses root lesion nematodes and reduces the incidence of Verticillium and Rhizoctonia fungal pathogens. Also, Meloidogyne hapla levels have been reduced after cover cropping with T. patula (Evenhuis et al., 2004). Thus, Tagetes patula is increasingly used to disinfect soils from these organisms as an alternative to MS. Our estimates for 2014 suggest that 70% of growers in the Netherlands use T. patula in their strawberry production systems but only once every 3–6 years. With an estimated 33% of the field acreage per year (Molendijk, personal communication), this represents around 700 ha/year for fruit and 400 ha/year for nursery production. This non-chemical solution has also been used in Belgium, Germany, Poland, and Ukraine but on a limited acreage. In Germany, for example, strawberry growers are advised to use another field in a crop rotation and/or to till in a catch/cover crop consisting of a combination of T. patula and T. erecta, to be planted in mid-May. This cover crop has to be weed-free and left to grow at least 4 months before it is incorporated into the soil (Krüger, personal communication). In many countries (Austria, Belgium, Ireland, Italy, the Netherlands, Slovenia, Switzerland, United Kingdom, and others) biofumigation practices are used at an experimental level and/or in a very small commercial acreage for strawberry fruit production.

Also, ASD has been used in the Netherlands for strawberry nursery production. The mode of action is the depletion of oxygen caused by decomposing organic matter under plastic film and the formation of toxic compounds that suppress pathogenic fungi, bacteria, and nematodes. The ASD procedures have been recently summarized by Shennan et al. (2014) and include: acquisition or on-site growth of 40 to 80 t/ha of green manure (or plant residues), incorporation of organic material into flat open field and/or furrows at 30 to 80 cm depth, light compaction of the top soil (always in summer with a Rotary Spading cultivator with a pressure roller (Molendijk, personal communication), covering the soil with an oxygen impermeable plastic (such as VIF or TIF film), maintenance of anaerobiosis under tarp for 4 to 6 weeks at air temperatures above 20 °C, and, finally, systematic soil preparation for strawberry fruit or nursery cultivation. Currently, this ASD technique is used in the Netherlands for several crops (maple, catalpa, asparagus, and strawberry nursery) in 70 ha (Shennan et al., 2014). ASD use in strawberry nurseries is currently practiced at 30 ha per year but is increasing (Molendijk, personal communication). Costs of ASD are high: application of VIF strips and sealing them with glue may cost as much as 3000 € per ha. Additionally, there are costs of growing or buying the green manure, applying irrigation, and discharge costs of the plastic film after ASD completion (Lamers et al., 2010).

Soilless systems for fruit production

With different types and technologies, soilless systems for strawberry fruit production are concentrated in few industries in the Rosati’s Regions 5, 3, and 2 (British Isles, Benelux, and Central/Southern Europe). Soilless production in the United Kingdom (3200 ha) represents two-thirds of the total British strawberry acreage and more than 50% of the total European soilless acreage (affiliated industries included). A significant development in that region is transition of nearly 95% of Irish soilless production industry from peat to coir (Kehoe, personal communication). In France, Belgium, and the Netherlands soilless production is very significant and table top systems prevail (Lieten, 2013). In these countries, the expansion of fruit production in substrates during summer (as opposed to soil-planted open fields) is an increasing trend (Lieten, personal communication). The surveys by the Centre Technique Interprofessionel des Fruits et Légumes (CTIFL) in France in 2014 showed the growth of soilless acreage from around 150 ha in July 2012 to nearly 650 ha in November 2013 (Granado, 2014). In France, in 2014 total estimated fruit production acreage was 3300 ha (similar to 2013) with 65% of acreage in substrates under high tunnels, 20% under small tunnels, and 15% in soil in the open field. Table top soilless production represented nearly 20% of this total acreage, mostly in high tunnels. However, according to 2013 estimates soilless production (20% of the total acreage) accounted for 60% of the total French strawberry fruit production. From the qualitative point of view, Switzerland and Cyprus have a high percentage of soilless production under plastic tunnels but the fruit production farms are rather small. The summary of soilless acreage for fruit production by country, and percentage of the total acreage is presented in Table 3.

Table 3. Soilless systems for fruit production (approximate estimation).

Country	Acreage (ha)	% of total acreage
United Kingdom	3200	66.0
France	650	19.8
Netherlands	600	28.6
Belgium	500	36.1
Spain	250	3.4
Ireland	214	95.0
Germany	150	1.0
Italy	123	3.3
Switzerland	100	20.0
Denmark	60	5.0
Sweden	50	2.4
Cyprus	30	50.0
Turkey	30	0.6
Morocco	22	0.6
Norway	20	1.3
Ukraine	10	0.1
Croatia	5	1.4
Greece	5	0.7
Lithuania	4	1.0
Portugal	3	0.6
Finland	3	0.0
Total	6029

Chemical solutions for fruit and nursery production

The summary of chemical fumigation acreage for fruit production and nursery by country, and percentage of the total acreage are presented in Tables 4 and 5. Soil fumigants are mainly used by the large Southern industries of Region 1 for fruit production and in all of the big commercial nurseries (except the Netherlands).

Table 4. Estimated acreage and methods of chemical soil disinfestation for fruit production.

	MS		Dazomet		1,3D+CP		CP alone
Country	ha	%^z	ha	%	ha	%	ha	%	Remarks
Turkey	2000	40	250	5	—	—	—	—	Some MS+MK
Morocco	1764	49	—	—	1411	39	353	10	1,3D:CP drip mainly
Italy	1301	35	150	4	1473	40	200	5	Daz Mix-Tiller. 1,3D+CP
Egypt	1160	20	25	0.4	—	—	—	—	1150 ha (20%) MB^y
Belgium	900	65	100	7	—	—	—	—	MS+MK (330 ha) Spading. Daz Mix-Tiller
Poland	700	2	50	0.1	—	—	—	—	MS Spading
France	528	16	72	2	—	—	—	—	MS+1,3D (257 ha) drip and Spading. Daz Mix-Tiller
Portugal	490	90	—	—	—	—	—	—
Romania	281	13.5	281	13.5	—	—	—	—
Spain	182	2.5	876	12	5329	73	730	10	MS shank and drip. Daz+1,3D (750 ha) drip for fruit. 1,3D:CP
Netherlands	100	5	—	—	—	—	—	—	MS Spading every 5^th year
Albania	55	100	—	—	—	—	—	—
United Kingdom	50	1	50	1	—	—	200	4	MS Spading. Daz Mix-Tiller
Germany	—	—	60	0.4	—	—	—	—	Daz Mix-Tiller
Total	9511		1914		8213		1483

^z% of total national acreage for fruit production.

^yEgypt is an A5 country of MP.

Table 5. Estimated acreage and methods of chemical soil disinfestation for nursery production.

	MS		Dazomet		1,3D+CP
Country	ha	%^z	ha	%	ha	%	Remarks
Turkey	80	40	80	40	—	—
Italy	136	34	—	—	264	66	MS Spading. 1,3D+CP
Egypt	33	33	1	1	—	—	33 ha (33%) MB^y
Belgium	80	77	24	23	—	—	MS+1,3D (30 ha). Daz Mix-Tiller
Poland	460	92	40	8	—	—	MS Spading
France	250	100	—	—	—	—	MS+1,3D (125 ha). MS Spading, shank and drip. Daz Mix-Tiller
Portugal	—	—	—	—	—	—	Calcic cyanamide (25 ha)
Romania	75	50	75	50	—	—
Spain	536	34	158	10	866	55	MS Spading. Daz Mix-Tiller. 1,3D:CP. Some CP alone
Netherlands	200	11	—	—	—	—	MS Spading every 3rd year
Albania	1	100	—	—	—	—
United Kingdom	50	71	20	29	—	—	MS Spading. Daz Mix-Tiller
Germany	—	—	20	13	—	—	Daz Mix-Tiller
Total	1901		418		1130

^z% of total national acreage for nursery production.

^yEgypt is an A5 country of MP.

For fruit production, MS is applied in Turkey (40% of the total acreage), Morocco (nearly 50%), Belgium (65%), Portugal (90%), Italy (35%), Egypt (20%), and Romania (13.5%), with a total acreage of about 9500 ha. In general, MS is applied either by shank or pre-plant drip injection. In some cases, MS is used in mixture with MK (Belgium, Turkey) and with 1,3D (France). For nursery production, MS is applied in more than 1900 ha, predominantly in France (100% of nursery acreage), Poland (92%), Belgium (77%), United Kingdom (71%), Romania (50%), Turkey (40%), Italy (34%), Egypt (33%), and Spain (34%). MS is also applied in mixture with 1,3D in Belgium and France. To overcome inconsistency in efficacy of MS related to soil conditions and application methods, a significant development in the European industry is a wide-spread adoption of Spading machines, starting in the Netherlands (Rotary Spading-Imants) (Runia and Molendijk, 2007) and followed by other manufacturers (Forigo in Italy, and others). A very high percentage of nursery acreage utilizes MS applied with this Spading technology in Poland, Spain (García-Sinovas et al., 2014), Italy, France, United Kingdom, the Netherlands, and Belgium. In Poland this application technology is also used in fruit production fields (700 ha and 2% of total acreage).

The use of dazomet, similar to MS, is increasing every year. Dazomet is the third most common chemical fumigant following MS and mixture of 1,3D and CP. For fruit production, dazomet is applied to 12% of the total Spanish acreage of Huelva (more than 875 ha), predominantly in combination with 1,3D during pre-plant drip fumigation. Dazomet is also used in Romania (13.5% of total acreage), Turkey (5%), Italy (4%), and Belgium (7%). For nursery production, dazomet is applied to more than 400 ha in Spain (10% of total acreage), Turkey (40%), Poland (8%), Romania (50%), United Kingdom (29%), and Belgium (23%). Similar to MS, inconsistent efficacy of dazomet has been improved with the use of Mix-Tiller machines (Forigo and others), in Italy, Spain, France, Belgium, United Kingdom, and Germany.

In spite of the current importance of 1,3D:CP in mixture and/or separate but simultaneous shank applications (Italian case), these fumigants are being phased out after the non-approval in the EU in 2010 and 2013, respectively. However, their use for fruit and nursery production is still critical in some Southern industries (Spain, Morocco, and Italy) and more than 8200 ha for fruit production and around 1500 ha for nursery were fumigated with these materials. For fruit production, mixture of 1,3D:CP is applied to 73% of the total Spanish acreage of Huelva (50% shank applied in preformed beds and 50% applied via drip irrigation). In Morocco, these fumigants are used in 39% and in Italy in 40% of the total fruit production acreage. In Spanish and Italian nurseries, major plant suppliers in the EU, more than 55% and 66% of the acreage, respectively, is disinfested with the mixture 1,3D:CP.

The biggest European industry for strawberry plant production is located in the Netherlands with 1800 ha in soil (1200 ha for frigo-plant and 600 for waiting bed production). Soil disinfestation practices are carried out every 3 years/crop cycles. Annually, 400 ha use Tagetes catch crop rotation and 200 ha use MS (Monam) while 30 ha per year use ASD.

Remaining issues for strawberry soil disinfestation in Europe

With emerging major soil-borne problems, it is likely that application of different solutions or/and their combinations for a single crop will be necessary to ensure the sustainable strawberry production. In soilless systems the costs of development and operations are high. New affordable methods of table top and soilless production (such as raised bed trough systems) and new methods for disinfecting substrates and fertigation are needed to be continuously adopted. To improve inconsistent efficacy of fumigants new methods and machinery for MS and dazomet application, already utilized, need to be further evaluated and developed.

For increased adoption of non-chemical methods for large Southern fruit production industries information, extension, and technology transfer to farmers on ASD, soil solarization and biofumigation methods are necessary in the short- and long-term and in the future as these methods continue to evolve. With regards to an unclear future of chemical fumigants in the EU, approval of new formulations and application technologies of 1,3D and CP under Regulation (CE) 1107/2009 is essential to maintain current production and to secure the continuity of strawberry production while alternative methods of disinfestation are being developed and gradually adopted.

Acknowledgments

We wish to thank the following experts and companies for providing accurate and updated information as personal communications for this comprehensive survey: A. Belaj, E. Kullaj (1) (Albania); R. Steffek (2) (Austria); D. Radkevich (3) (Belarus); T. Van Delm, D. Bylemans (4) (Belgium); H. Kutinkova, V. Dzhuvinov (5) (Bulgaria); B. Duralija (6) (Croatia); D. Neocleous (7) (Cyprus); R. Chaloupka, J. Sedlak (8) (Czech R.); N. L. Jensen (9), T. Todsen, O. Scharff (Denmark); S. Soleiman (Egypt); R. Rätsep (10), U. Moor (Estonia); P. Parikka (11) (Finland); G. du Fretay (12), J.P. Bosc, N. Le Roch (France); E. Krüger, K. Diehl (Germany); M. Vasilakakis (13) (Greece); F. Dénes (14) (Hungary); E. Kehoe (15) (Ireland); G. Baruzzi, W. Faedi, M. Piardi, C. Spotti, B. Mezzetti (Italy); V. Laugale (16), J. Plishevska (17) (Latvia); R. Rugienius (18) (Lithuania); M. Kiprijanovski (19) (Macedonia); L. Anghel (20) (Moldova R.); R. Nestby (21) (Norway); P. Lieten, L. Molendijk, G. Van Kruistum (22), W.T. Runia (The Netherlands): E. Zurawicz (23) (Poland); M. G. Palha (24) (Portugal); M. Coman (25), M. Sturzeanu (Romania); I. Kozlova (26) (Russian F.); M. Nikolic (27) (Serbia and Montenegro); G. Libiakova (Slovakia); D. Koron (28) (Slovenia); A. Martinez-T., M. Becerril, M.A. Hidalgo, A. Arjona, D. García-Sinovas, M. Andrade, M.J. Zanon, A. de Luna, C. Adalid, M. C. García-Romero, M. T. Ariza, J.L. Alonso-Prados, J.A. Cristóbal, J.J. de León, Agroquímicos de Levante, Agrofresas (Spain); B. Swensson (29) (Sweden); A. Ancay (30) (Switzerland); E. Kasfkas, A. Yaltir (31), S. Serce (Turkey); A. Yareshchenko (32), O. Bosyy (Ukraine); D. Simpson (33) (United Kingdom); Certis Europe Team, Dow AgroSciences Team, Arkema Team (European Union).