Field
Inspection
Field
inspection, that is, inspection of standing seed crops is an essential step in verifying
conformity of seed crops to prescribed certification standards.
Objective
To verify seed origin and identity of
the variety.
To collect information on cropping
history of the see field, that is, to verify whether the seed field meets the prescribed
land requirements.
To check crop and cultivation
conditions.
To check isolation distance.
To check freedom from impurities,
namely, other crop plants and weeds plants.
To check freedom from seed-borne
disease.
General principles
All field inspections must be made by
well-trained and qualified personnel. The inspector has to know the prerequisites and
standards.
The prescribed procedures and
techniques of field inspection and the minimum number of inspections specified in the
certification standards should be strictly adhered to.
The inspections should be made without
prior notice.
The seed inspector should achieve full
co-operation from the seed growers, even in the case of the rejection of a field.
Upon arrival at the seed farm, the
inspector should check all information about species, variety, seed origin, cultivated
area, class of seed, cropping history of the field to be inspected, and known adjacent
fields of the same species, which may be dangerous from isolation point of view.
Each field and its boundaries must be
pointed by the seed grower.
During the walk in the field, the
inspector must make estimates of other varieties and impurities, diseased plants, general
condition of the crop, applied farm practices and possible yield.
If the direction of plant rows permits,
the inspector should walk through his side or back.
Method
The inspection of a
seed crop is done at different stages of crop growth so as to make various verifications
and estimates of various impurities, off-types and diseases, etc.
Crop
stage of inspection
1. Inspection
at the time of sowing
Sowing time inspections to educate the
farmers participating in a certified seed production. Programme for the first time, or at
times when a new crop is introduced, are very helpful in maintaining good quality of seed.
In biennial crops the main objective is to verify the purity of roots/stem at the time of
transplanting.
2. Inspection
during pre-flowering/vegetative stage
The purpose
of pre-flowering inspection is to educate growers regarding plants to be rogued and to
suggest other corrective measures.
3. Inspection during flowering stage
Check whether various corrective
measures, if suggested earlier, have been carried out.
Check or re-check the land and
isolation requirements, planting ratios and source seed.
Take detailed counts for various
contaminating factors.
- Advise the farmer to continue roguing
during flowering season.
4. Inspection during post-flowering and pre-harvest stage
The corrective
isolation measures suggested earlier may also be checked to ensure whether these have been
done.
5. Harvest time inspection
Harvest
time inspection is the last inspection conducted on a seed crop. During this inspection
detailed counts are taken for various factors, and isolation requirements are finally
checked to confirm whether the seed crop has met the requisite field standards. The farmer
should be given necessary instructions regarding precautions he should take during
harvesting/threshing and supply of the material to processing plants.
6.
Contaminants to be observed during field inspection
Plants of
the same crop species as the seed crop, differing in the expression of morphological
characters such as plant type, branching habit, pigmentation, etc., are classified as
off-type.
In hybrid
seed production involving use of cytoplasmic-genetic male sterility three different lines,
namely, a male sterile line (A line), a maintainer line (B line) and a restorer(R line)
are involved. While tacking field counts only those B line ears which have 2cm
or more of the ear length shedding pollen or which have already shed pollen, are counted
as pollen shedders.the grower must be informed, so that the whole b line plants can be
completely removed before they commence shedding3
Tassels on
female parents plants found during field inspection to have come out but which have not
commenced shedding are not counted, but special mention as not commenced
shedding is made for subsequent inspections to be done sooner
Inseparable
other crop plants, are plants of cultivated crops found in the seed field and whose seeds
are so similar to the crop found in the seed field and whose seeds are so similar to the
crop seed that it is difficult to separate them economically by mechanical means. If its
stage of growth is so widely different from that of the seed crop that it cannot bear seed
by the time the seed crop matures, it need not be counted. However, the presence of an
inseparable other crop plant in widely differing stages is made for verification during
subsequent inspection
The plants
affected by diseases should invariably be counted and roguing of these plants from side
fields. |
Ag.
Technologies
(Seeds)
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