§ Motion made, and Question proposed, That this House do now adjourn—[Mr. Goodlad.]
§ 8.2 am
§ Mrs. Marion Roe (Broxbourne)
The glasshouse industry faces a threat to plant health of major proportions. Unless action is taken soon, that threat may decimate the United Kingdom's glasshouse industry. There is little time to take action, and an incorrect decision now may prove catastrophic for glasshouse growers and pose a real risk to those growing outdoor crops. I am grateful for the opportunity to raise this important subject before the Christmas recess. In this case, time really is of the essence.
The threat is due to an insect known as the South American leafminer—liriomyza huidobrensis. Until October this year, it was unknown in the United Kingdom, but findings have since been confirmed in at least 28 nurseries, spread across southern England but concentrated especially in the Lea valley. The pest is spreading and there are no effective control measures available to United Kingdom growers. The pest has its origins in central and south America. It is a European Community quarantine organism and a United Kingdom statutory pest, which means that growers must report any findings to the Ministry of Agriculture, Fisheries and Food plant health and seeds inspectorate and that all European Community countries must inform the European Commission of any occurrence and prevent its spread within, and between, member states.
The leafminer appears to have reached the United Kingdom via Holland, where it was first positively identified in August this year. By that time, it had become widespread in the Netherlands and was causing severe economic damage to edible and non-edible crops. Strict control measures are still being applied there in an attempt to restrict its spread. More than a third of the lettuce crop in the Westland area has been destroyed, and controls on exports from affected nurseries are being rigidly enforced.
The South American leafminer is known to cause severe damage to a wide range of both edible and non-edible crops. Of particular concern are vegetables such as lettuce, tomato and cucumber, and ornamentals such as chrysanthemums and gypsophila. The insect does its damage in the larval stage. The larvae mine between the upper and lower surfaces of the leaves, disfiguring crops, rendering them unsaleable and causing yield losses in crops such as tomato. Severe infestations can cause entire crops to develop distorted and discoloured leaves.
I understand that economic damage in the United Kingdom has, to date, been minimal, owing to the low levels of infestation and the eradication policy of MAFF's plant health and seeds inspectorate wherever outbreaks have occurred. It is crucial that we learn a lesson from Holland, where the pest has exploded into plague proportions within a single season.
Our only hope of controlling its spread in the United Kingdom is to eradicate it from ornamental crops while the incidence on edible crops is at a very low level. Once it becomes established on edible crops—it has already been detected on such crops in at least four nurseries—the possibility of chemical control will be greatly reduced, and widespread crop destruction may then become necessary to control its further spread. Nurseries replanting edible 595 crops are at greatest risk, especially cucumber growers who are at risk both from the damage caused by the pest and from the likelihood of destruction orders to control outbreaks because chemical controls for such crops are very limited.
Unless the many outbreaks on ornamental crops are eradicated now, there is a grave risk that the scourge will spread to edible crops. Our best hope is to eradicate the pest during the winter. We do not know whether it can survive outdoors through a European winter, and severe frosts will certainly be in our favour. The danger is that, if it is still in the country in the spring, its spread from nursery to nursery will be rapid during the summer. Moreover, we are unable to predict the consequences for outdoor crops, which are also host plants and include celery, beans and potatoes. I am convinced that growers should have all the weapons that they need to bring the pest completely under control now.
There are non-chemical methods of control. The leafminer is susceptible to a number of parasites. With no experience of their use, however, and given the varying effectiveness of biological control agents, it is clear that such controls do not offer an immediate solution. As I have emphasised, the problem must be dealt with now, and growers must therefore rely on chemical methods of eradication.
If the leafminer is to be controlled successfully, both adult and immature stages must be destroyed. Owing to its habit of mining, however, only a few chemicals are able to move through the leaves to reach the larvae and kill them. Unfortunately, the pest shows evidence of resistance to chemicals recommended for its control. There is, however, an insecticide—Abamectin—which provides excellent control by killing the larvae within their mines. It is used on ornamental crops in France, Spain and the United States, and will shortly be used in Germany; it is also available in Guernsey and the Isle of Man. The Dutch, too, appear to be gaining control of the leafminer, by means of a chemical programme which includes Abamectin. The insecticide is already used on tomatoes in Spain and the United States, and will gain approval for use on edible crops in Holland early in the new year.
In the United Kingdom, however, this insecticide, which is so desperately needed by growers, has been in the queue awaiting evaluation by the Ministry of Agriculture, Fisheries and Food for more than 18 months—since April 1988. Since the introduction in 1986 of new legislation governing the approval of pesticides, I understand that only 11 new molecules have been approved and there are now over 40 molecules waiting to be evaluated. Even if Abamectin were to be looked at by the MAFF scientists tomorrow, it would still take some six months for the product to gain approval. Abamectin has been in the queue for too long, and growers' livelihoods are at risk now.
I stress that I fully recognise the crucial importance of allowing only safe pecticides to be used in this country, but I find it hard to believe that such concerns are any weaker in Holland and the United States where Abamectin is already in use. My feeling is that, faced with an emergency such as the one now threatening the glasshouse industry, MAFF and the other Government Departments concerned with pesticide approval must be prepared to adopt a more flexible approach.
An acceptable solution would surely be the restricted release of Abamectic now to deal with outbreaks of the 596 leafminer on non-edible crops. While allowing limited use of Abamectin, MAFF should lay down the most stringent safety precautions to protect spray operators. At present, such use is allowed on 2 hectares under an experimental permit. I see no reason why, in these exceptional circumstances, that could not be extended to cover the nurseries affected by this newly invading pest. Meanwhile, the product should be brought forward for evaluation by the MAFF scientists now to enable it to be fully available to growers as early as possible next year. The scientists should make full use of the data used to satisfy Dutch and American departments of the chemical's safety for spray operators.
What makes the situation even more extraordinary is that the product was sold perfectly legally in the United Kingdom under the limited clearance system up to January 1987. It seems incredible that a plant health disaster of this scale could take place because Departments are unwilling to release a product which is available for use under indentical conditions in Holland and the United States and which was quite safely used in this country less than two years ago.
It is difficult to overstress the seriousness of the situation. Many growers have recently invested in new glasshouses with the help of the MAFF grant, but a continuation of high interest rates and poor trading results has resulted in their entering the winter with increased overdrafts and undiminished loans. If growers suffer from the leafminer attack and are forced by MAFF to destroy their crops without compensation, many businesses will simply be unable to survive. How ironic it would be if those MAFF grants were wasted due to inaction now.
The South American leafminer must be brought under control quickly and completely. Abamectin has proven ability to control the pest and is being used successfully in other European countries and in the United States. Ornamental and edible produce are likely to be imported for sale in the United Kingdom after treatment with Abamectin, yet United Kingdom growers are unable to use it to protect their livelihood.
I am most grateful to the Minister, my right hon. Friend the Member for Suffolk, Coastal (Mr. Gummed, for meeting and listening to a delegation of growers whom I brought to the Ministry to see him last week. I repeat to my hon. Friend the Parliamentary Secretary the message that we delivered then—let us please have a rational approach to this disastrous situation and let us see the Ministry respond by treating United Kingdom growers as fairly as their European counterparts.
§ The Parliamentary Secretary to the Ministry of Agriculture, Fisheries and Food (Mr. David Maclean)
I thank my hon. Friend the Member for Broxbourne (Mrs. Roe) for choosing to raise a subject which is of very real concern to commercial growers throughout the country and, of course, in her constituency in particular. I congratulate her on the forceful and powerful way in which she delivered her case this morning. The debate enables us to clear the air somewhat and to set out clearly what the Government are doing to combat the South American leafminer and to try to ensure that it does not become established in this country.
Liriomyza huidobrensis, the South American leaf-miner, is a very serious threat to the horticulture industry. 597 This small fly, about 2 mm in length, has a very wide host range, feeding on plants from at least 17 different families, both ornamental and vegetable, including field and glasshouse crops. Although hon. Members might not be familiar with that nasty little beastie, I am not being flippant when I say that in the Lea valley talk is of little other than liriomyza huidobrensis.
First, let me make it clear that we are in no doubt as to the threat to horticulture presented by the South American leafminer, particularly in view of the wide range of plants that it attacks. It is certainly our aim to prevent this pest from gaining a foothold in the United Kingdom, as we have so far succeeded in doing with liriomyza trifolii, the North American leafminer, which has been a threat to our growers for a number of years.
Secondly, I underline the fact that, while the South American leafminer has long been recognised as a potential danger—and therefore prohibited under both the relevant EC directive and our national legislation—it has become an actual threat only in recent months. I understand that the Dutch authorities first became aware of its presence in the Netherlands in August, as my hon. Friend said. They notified the EC plant health standing committee in Brussels at its September meeting and they introduced strong measures to eradicate it from both domestic and export trade.
As soon as we became aware of the threat, we began targeting inspections of imported Dutch plant material and produce to pick up any contaminated material that might reach the United Kingdom despite the checks being carried out by the Dutch. We contacted the Dutch Government at ministerial level and we sent officials to the Netherlands to see on the ground how the Dutch measures were being enforced and to discuss with them ways of tightening the controls.
Some people have suggested that there should be a complete ban on imports of host plants from the Netherlands. That is wrong. We believe that the range of measures agreed with the Dutch authorities provide a good basis for preventing that pest from gaining a permanent foothold in Britain and show the Dutch authorities' determination to do their part to prevent infested material from reaching Britain. With all the complexities of the horticultural trade, total bans on imports of particular plant species could damage the economic prospects of the very firms whose interests we are trying to defend. It is better to secure clean imports than to stop trade altogether. However, we shall not hesitate to impose a total prohibition on any plant species if we consider it necessary to prevent the leafminer from becoming established here.
As a result of our negotiations with the Dutch authorities, we have reached agreement with them on a range of measures aimed at minimising the risk of infested material reaching this country. These include a number of steps by the Dutch authorities to tighten export examination procedures of plants known to be hosts of the leafminer. We have agreed a widening of the range of cut flowers from the Netherlands which now require a plant health certificate—and therefore inspection—before they can be exported to Britain. We also persuaded the Dutch authorities that chrysanthemum cuttings must be fumigated before export to kill off any infestation.
598 In addition, imports of radishes and horse radishes from the Netherlands have to be free of leaves. The authorities in the Netherlands have also let it be known that they will not be issuing any plant health certificates after 14 December for pot plants of known host plants, which effectively prevents their export to this country. They took this action because their industry was unwilling to meet our requirement that there should be inspections at the growing stage for these host plants because of the risk of pupae in the soil, which might not be detected by normal export inspection methods.
So far, this pest has been identified only on material coming from the Netherlands—which is, of course, among the world's leading horticultural exporters—but we are aware of the risk of its spreading to other Community member states and are therefore maintaining vigilance on imports from other sources. At the last meeting of the Community's plant health standing committee, my officials pressed the Commission to consider action against the pest on a Community wide basis. We know that several other member states are also very worried, and we shall continue to press for Community action.
We consider that the measures taken have greatly reduced the risk of this pest becoming firmly established here. The signs so far would appear to give confidence that they are beginning to have some effect. It is true that there have been findings on about 30 British nurseries, affecting mainly chrysanthemums, but including lettuce, cucumber and celery, and I acknowledge that a number of those have been in my hon. Friend's constituency.
However, nearly all those outbreaks showed signs that the pest had been there for some time, certainly well before the measures that I have outlined were introduced. There have also been findings on imported produce and flowers from the Netherlands, but those have become noticeably fewer in the last few weeks.
I appreciate the genuine concerns expressed by growers that the range of pesticides presently available for use against the South American leafminer may prove insufficient to eradicate it before it establishes itself, not only on ornamental but on edible crops.
As for chemical controls, we have evidence that existing pest control programmes are beginning to have an effect and we have taken action to strengthen the growers' armoury by increasing the number of permitted applications of triazophos, which is marketed as Hostathion, for use against the South American leafminer. We have also improved the rate of application and we are optimistic that those measures will be effective.
Calls have been made—my hon. Friend made a strong call —for the pesticide Abamectin, which is approved in Holland on non-edible glasshouse crops and in Spain on certain edible crops, but not in the United Kingdom, to be made available in this country. It is not that simple. The pesticide must be evaluated on the basis of its behaviour under United Kingdom conditions. Differences of soil, climate and growing methods must all be taken into account and our standards for operator and consumer safety must be met before a pesticide can be approved for use in this country.
The House will appreciate that we cannot assume the responsibility for authorising the use of these chemicals without satisfying ourselves on those vital safety matters. The request from the National Farmers Union that the 599 strictly limited experimental permit for Abamectin should be extended to allow use on all affected sites cannot be met without a full evaluation of data on operator toxicity.
But I am pleased to announce to the House this morning that we have already started the evaluation of this pesticide, and my Department is now liaising with the Dutch authorities to determine whether their evaluation can be used to speed our assessment. It is hoped that the operator toxicity evaluation will be ready in about two months' time.
I cannot and will not anticipate the results, but we hope that it may then be possible to permit the use of Abamectin on affected sites to combat liriomyza huidobrensis. Evaluation of other parts of the data package to allow consideration of commercial approval will follow, but this chemical will not be allowed on the market for general use unless and until the independent experts of the Advisory Committee on Pesticides recommend that it is safe to do so.
Let me make it clear exactly what that means. If there is no risk to operators, the use of Abamectin can be authorised on an experimental basis but only on ornamental plants. It cannot be extended to food crops. Once all the scientific information has been assessed, the Advisory Committee on Pesticides will be able to say whether Abamectin is safe for more extended use on other crops. I must emphasis that that decision is many, many months away.
The companies with applications for new pesticides that are in the queue are entitled to expect fair treatment, which 600 they have always received from the pesticide registration authorities. I must make it clear that we have agreed to this exceptional course of action in respect of Abamectin solely because of this rare opportunity to eradicate an exotic pest before it gains a foothold in this country.
It is clear that, whatever the measures taken, this nasty little beastie will remain a real danger to horticulture. I cannot, therefore, emphasise too strongly the importance of growers continuing to remain as vigilant as possible for the signs of the pest on their farmholdings. To help them identify this leafminer—it should not be forgotten that there are numerous native leafminers, as well as the North American leafminer with which it could be confused by the layman—we shall shortly be issuing an illustrated guidance leaflet. If they are at all suspicious that the pest is present, I would exhort nurserymen and others to contact their local plant health and seeds inspector at once. We intend to increase the number of such inspectors working on the checking of plant material specifically looking for this pest.
All in all, we consider that the extensive measures that I have described should enable us to prevent the pest from becoming established here. We shall, however, keep the matter under close review. As I promised my hon. Friend earlier, we shall not hesitate to take any further measures if we consider them necessary.
§ Question put and agreed to.
§ Adjourned accordingly at twenty-seven minutes past Eight o'clock.