|
Frequently Asked Questions
|
|
Virology and Bacteriology Laboratory Plant Tissue Culture Laboratory
|
|
|
|
What is the scope of plant quarantine in Plant quarantine helps to improve the plant health status by:
Preventing the entry of harmful organisms by intercepting any suspicious material, and
Examining the consignments (identity and physical checks) and accompanying documentation by administrative enforcement.
What difference did accession to the EU make in the export or import of plants and plant materials?
Since accession to the EU movement
of plants and plant materials
between
What items do I need to present in order to get import approval from the Plant Health Point of View?
You are requested to supply information of the plant material to be imported
into the
When is a consignment withheld by the plant health inspectorate?
A consignment is withheld when: i. the plant material is suspected of harbouring harmful organisms, ii. the plant material harbours harmful organisms, iii. the plant material does not have the correct documentation (including occasions when soil is present with live plants which are supposed to be soil-free).
What happens if a consignment is suspected of harbouring harmful organisms?
The plant health inspectorate does not approve the release of the consignment. The inspectorate then takes samples and sends them to the Plant Health Laboratories or the Plant Biotechnology Centre for further analysis. The consignment is withheld until laboratory tests are carried out. The importer is informed of the outcome of the tests and the consignment is either released or further measures are taken.
What happens if a consignment contains harmful organisms?
The consignment is either: i. sent back to the exporting country, or ii. destroyed locally (the procedure depends on the plant material), or iii. treated accordingly depending on the plant material/harmful organisms.
What items do I need to present in order to get an export approval from the Plant Health Point of View?
You are requested to supply information on the plant material to be exported. The inspectorate has the obligation to check and verify that the plant material to be exported is free from harmful organisms and that the particular material conforms with the Additional Declarations. Once the material is approved a phytosanitary certificate for export is issued by the inspectorate.
For further information on the plant quarantine station, please refer to the plant quarantine page.
|
|
|
|
What are viruses?
Viruses are microscopic infectious agents, which multiply only within living cells of an appropriate host. They may or may not cause obvious symptoms in infected plants.
How can viruses be transmitted?
Different viruses can be transmitted by different means. These include: i. Mechanical contact: e.g. physical contact between diseased and healthy plants and/or by injuries to the roots ii. By seeds, pollen or by the use of infected propagation material iii. By vectors which bring the viruses in direct contact with the infected sites. Vectors include insects, nematodes and fungi.
What are the typical problems caused by virus and virus-like diseases?
i. Nil to drastic reduction of yield ii. Reduction of fruit size and quality iii. Premature fruit drop iv. Reduction of vigour and life expectancy v. Induction of nutritional problems vi. Increased susceptibility to other diseases vii. Significant reduction of graft uptake
Are virus and virus-like diseases easily detected in the field?
No, not always. This is because symptoms may be specific, that is, they can be attributed to other agents and pathogens (e.g. yellowing, wilting).
Sometimes the virus may be present in the plant but the infection is latent, that is, no symptoms will be visible.
How can plant virus diseases be controlled?
The control of viruses is preventive and indirect. There is no anti-virus treatment available to control these diseases in the fields and it is virtually impossible to eliminate these internal pathogens with the use of chemicals. Different preventive measures can be taken and these include control of virus vectors, use of healthy propagation material, crop rotation etc.
For further information on the virology laboratory, please refer to the virology and bacteriology page.
|
|
|
|
What are bacteria?
Bacteria are single-celled, microscopic organisms that occur naturally almost everywhere on earth including soil, water, organic matter, or the bodies of plants and animals. Some bacteria are important as they cause disease in both plants and animals.
What is the difference between a virus and a bacterium?
As bacteria and viruses are both microscopic agents which cause disease people often confuse the two. Viruses and bacteria differ greatly in size, viruses being much smaller than bacteria. Another difference is their structure. Bacteria are more complex compared to viruses. The main difference however lies in the way they reproduce. Unlike bacteria viruses can only reproduce inside living cells.
Can one distinguish bacterial infections from other diseases?
It is difficult to distinguish bacterial infections from other diseases by solely observing symptoms. Similar pathological conditions may be caused by quite different agents. There are bacterial soft rots and fungal soft rots, insect galls and bacterial galls, fungal wilts and bacterial wilts. There are several examples of plant hosts affected by different bacterial diseases, which cannot be distinguished on the basis of symptoms alone. Such diseases would require laboratory isolation and identification of the pathogen for correct diagnosis.
What are quarantine bacteria?
These are bacteria of potential economic importance which are subject to official control to protect countries from the introduction and spread of these pests.
How can bacterial diseases be controlled?
As in the case of viral diseases, control of bacterial infections is largely preventive as there are no chemical treatments available.
For further information on the bacteriology laboratory, please refer to the virology and bacteriology page.
|
|
|
|
Plant Tissue Culture Laboratory
What is plant tissue culture?
This is a term used for the range of procedures used to maintain and grow plant tissues and organs (stems, roots, embryos) in aseptic (sterile) culture. Plant tissue culture is widely used for in vitro vegetative propagation of plants. This is known as Micropropagation.
How is micropropagation carried out?
A small piece of plant tissue (explant) is taken from the donor plant and is cultured on a nutrient medium in sterile in vitro containers. By changing the composition of the medium and the environmental conditions (temperature, light regime etc..) the development of this piece of tissue can be directed towards different developmental patterns and finally a whole plant can be regenerated. All the offspring come from a single plant and thus have their genetic makeup identical to each other and identical to that of the mother plant. These are thus called clones.
What are the advantages of micropropagation over the conventional way of growing plants?
i. It is a fast method of propagation, producing thousands of plantlets in a matter of months. ii. Healthy plant material is ensured since soil and other disease organisms are excluded during the propagation cycle. iii. The method is programmable to meet specific targets of time and quantity because it is independent to seasonal changes and the weather. iv. Micropropagation saves an enormous amount of care which is usually required by cuttings and seedlings (i.e. watering, weeding, spraying etc..). v. Excess material produced can often be stored over long periods. vi. Conservation of species and cultivars in small spaces.
What are the constituents of the tissue culture nutrient media?
These include: Water Inorganic salts Plant growth regulators Vitamins Amino acids Carbon source Solidifying agents (in case of solid medium)
For further information on the plant tissue culture laboratory, please refer to the plant tissue culture page.
|
|
|
|
Which plants are covered by the subsidiary legislation regarding seeds and other plant propagation material?
The legislation applies to agricultural plants (cereals, fodder plants, potatoes) and vegetables, vines, fruit trees, forest trees and ornamental plants.
Why has the legislation been established?
The legislation ensures that the quality of the propagation material offered for sale conforms to a number of quality standards and therefore, agriculture and the country's growers are protected against losses that can result from sowing or planting low quality plant material of poorly adapted and inferior varieties.
Why is it important to have good quality seeds on the market?
Seed is the essential element for establishing, expanding, diversifying and improving agriculture. The availability of high quality seeds of a wide range of varieties to the grower is one of the major keys for achieving food security. The agronomic value of seed is its high yielding ability. The use of good quality seed will result in a high harvest index, reduced risks from pest and disease pressure, higher profits and higher levels of nutrition. Customers will have access to a greater variety and quantity of agricultural produce of better and more uniform quality. The country as a whole will benefit from improvements in the agricultural economy.
With regards to seeds of agricultural plants and vegetables, what are the processes that seeds have to undergo in order to verify their compliance to the legislation?
Official field and crop inspections (pre-harvest) and seed tests are carried out by performing random checks. During field inspections, the inspectors will examine the cultural condition of the field, the stage of development and the condition of the crop from which seeds are to be marketed. Germination, genetic identity and purity, and seed health are some of the aspects dealt with in seed testing. Only seeds that have been verified and approved by the Plant Health Department will be eligible for certification.
What is the main aim of seed certification?
The objective of seed certification is to maintain and make available high quality seeds to growers. It has been and continues to be very important in maintaining genetic integrity throughout the multiplication process and particularly, in promoting improved varieties developed by research. As mentioned earlier, besides genetic identity and purity, seed certification systems include seed quality standards. Seed certification is mandatory for a number of plant species as specified in the legislation and optional for others.
For further information on the seed-testing laboratory, please refer to the seed-testing laboratory page on the Ministry website.
|
|
|
|
What is the aim of certification?
The aim of the certification scheme is to produce healthy, virus-free stone fruits and olives for the benefit of local growers. This system requires that all the material chosen for certification must follow certain stages of propagation under hygienic conditions, i.e. free from any disease infection.
Which are the stages involved in certification?
There are different stages: i. Selection of healthy plants and of pomological quality. ii. Selection of plants that are virus-free. If not, there will be production of base plants that are free from viral disease by means of heat therapy or by in vitro propagation. iii. Plants that are kept as nuclear stock are grown under strict controlled conditions that ensure plants are free from air borne and soil diseases. iv. Production of trees that have the same characteristics as the trees grown in the other mother block (mother plants). v. Multiplication of the nuclear stock in one or more phases of growing plants in a sterile environment. vi. Distribution of grafted healthy material to nurseries. vii. Production of material virus-free or virus tested. This material is subject to strict sanitary controls that includes various tests.
What is virus-free material?
Virus-free material is material which has been tested and found free from infection according to internationally recognized scientific methods. Regular inspections are being done in nurseries producing virus-free material in order to be sure that the growing crop is being maintained under conditions ensuring freedom from infection and is considered to be free from all viruses and virus-like pathogens.
What is virus-tested material?
Virus-tested material is material which has been tested and found free from infection according to internationally recognized scientific methods. It is found to be free from symptoms of any virus or virus-like pathogen by growing season inspection, and the material has been maintained under conditions ensuring freedom from infections.
What is C.A.C. material?
C.A.C. stands for Conformitas Agraria Communutatis. This means that the propagating material and fruit plants satisfy the minimum conditions laid down for that category relative to the species concerned.
For further information on certification, please refer to the certification page.
|
|
For further information or comments please click here |
