Agriculture Reference
In-Depth Information
investigating a number of different selection options
within a narrow time schedule between final assessment
of genotypes and preparations for planting the following
stage trials.
correct interpretation to standard analysis it should be
noted that many analysis types (e.g. multi-variate anal-
ysis) are now readily available to non-qualified workers
but that interpretation of these results often requires an
experienced person. The point is, therefore, that statis-
ticians should not be ignored and where possible they
should be consulted and encouraged to contribute ideas
in data interpretation.
Data transfer
The amount of data collected on individual genotypes
in a plant breeding programme is directly proportional
to the stage of selection. By the most advanced stages,
data from surviving lines will have been collected over
several years and locations. If plant breeding database
systems are to be of a useable size and if all information
available is to be stored together in a common database
then each season either:
Ease of use
One feature about computers and computer software
that has not been discussed is the ease of operating
the system. Many software packages are
user friendly
,
which means that they can be used by relatively inexpe-
rienced staff. This does not however, imply that these
database systems can be used without computer train-
ing. There will be at least minimal training required if
a database scheme is to be integrated into a breeding
programme.
Most user friendly computer packages give clear and
precise instructions in the form of prompted messages
to which the user replies with one or more operations or
data entries. In many cases these prompted instructions
can partially eliminate the need for 'user manuals'. It
is, however, general experience that a combination of
prompted commands along with a fully documented
and a concise users' manual will normally be required.
Records for discarded breeding lines must be deleted
from the database and new data storage allocated to
those selected lines, or
•
•
Selected lines must be transferred, along with any data
collected, to a new database where additional storage
is available
Either option can be used and both are equally efficient.
If the first option is chosen the old database can first be
copied before the unwanted records are deleted. This
allows access to data from discarded lines, which can
often be used in the future, for example to gain an
indication of particular defects of specific parents.
RELEASE OF NEW CULTIVARS
Statistician consultation
It is essential that agricultural experiments have clear
objectives and that they are well organized and designed
based on sound statistical reasoning. Consultation with
qualified statisticians should be done before, and also
throughout, the experimentation period. Plant breed-
ing assessment trials are no exceptions. There has been
some concern that statisticians will not be consulted
if breeders are capable of easily generating a number of
different experimental designs and performing complex
analyzing of data from these experiments. Care must be
taken to ensure that the appropriate design is chosen
to answer the questions required. Most plant breeders'
trials are, however, of a standard form where a number
of test genotypes are compared in performance with a
number of standard or control cultivars. Although the
majority of plant breeders are more than capable of using
the appropriate experimental design and making the
The ultimate goal of any plant breeding programme is
to develop superior genotypes and to release these into
agriculture as new cultivars. The final stage of a breeding
scheme therefore involves the process of release, perhaps
protection, and distribution of planting material to the
seed industry and/or the farming community.
The first part of this process is when the breeder
decides that a particular genotype has merit as a new cul-
tivar. This decision will have been made having observed
the performance of the potential new cultivar as it
passes through all the stages of the breeding programme.
This would entail a number of years and in, the more
advanced stages, and a range of different locations. It
cannot be stressed too strongly that if there is any doubt
regarding the worth of a potential cultivar then these
doubts must be addressed before deciding to release a
new variety. The general agricultural community does
