By R. Bourdeix, XXXX, and XXXX, 2019 - In construction
According to the Stantech manual:
Note from R. Bourdeix
In theory, for pure conservation purposes, sample size for dwarf types can be smaller than that of the tall types since dwarfs are relatively homogeneous. However, as long as the mode of multiplication is through the seednut, dwarfs will often be used as female parents or mother trees for hybrid production, hence they should be well represented if breeders want to be able to produce experimental hybrids and test them.
According to the Stantech manual:
Population size - The recommended sample size for each population or variety in a coconut field
ranges from 72 to 96 palms for a heterogeneous tall population. Lower sample size could be used
for homogeneous dwarfs, but maintaining the same number is advantageous.
Note from R. Bourdeix
In theory, for pure conservation purposes, sample size for dwarf types can be smaller than that of the tall types since dwarfs are relatively homogeneous. However, as long as the mode of multiplication is through the seednut, dwarfs will often be used as female parents or mother trees for hybrid production, hence they should be well represented if breeders want to be able to produce experimental hybrids and test them.
For producing for instance the cross of the Malayan Red Dwarf (MRD) with a New Tall Variety 1 (NTV1), breeders generally use 48 female parents from MRD and 24 female parents from NTV1, and make two sets of 48 controlled pollinations with bagging. This will need two monthes.
Imagine you have 6 New Tall Varieties to test (NTV1 to NTV6). If you want to make a crossing programmme with MRD for testing 6 experimental hybrids, you need to have at least 150 MRD palms, and the pollination programme will take 4 monthes. If you have 300 MRD, the pollination programme will take only two monthes and the seedlings will be more homogeneous in age.
It can also be imagined some "small Dwarfs units' specially designed for production of experimental hybrids by cheaper open pollination; each new Tall variety being tested by 4 to 4 different Dwarf varieties.
According to the Stantech manual:
"To conserve and at the same time characterize the sampled population as effectively as possible, they
should be planted following an appropriate design. Tall and dwarf types should be planted separately,
using one control cultivar for each type, with at least three replications. Planting distance is 9 m
triangular for tall and 7.5 to 8.0 m for dwarfs. A single accession comprising three replicates and
elementary plots of 5 x 6 palms (i.e. 90 palms per accession) is appropriate. This design can be
modified if a sufficiently large plot is not available. However, each accession should be represented
by at least 72 palms, with a minimum of two replications, set out in square or rectangular plots or
blocks of at least three rows per replicate. Failing a block design, it is essential for the control to be
sufficiently represented (one control plot for every four collection plots)."
About coconut accessions conserved in PNG ICG
To be completed
To be completed
