Descriptors for sweet potato (Ipomoea batatas) was developed by Dr. Z. Huamän of the International Potato Center (CIP), Lima, Peru.
This list is a revised version of the publication "Huamén, Z. 1988. Descriptors for the characterization and evaluation of sweet potato genetic resources. pp. 331-355. In: Exploration, Maintenance and Utilization of Sweet Potato Genetic Resources, Report of the First Sweet Potato Planning Conference, February 1987. Lima, Peru: International Potato Center. 369 p.".
CIP, AVRDC, IBPGR. (1991). Descriptors for sweet potato. International Board for Plant Genetic Resources, Rome, Italy.
Ability of vines to climb adjacent stakes placed in those accessions showing twining characters
Legend:
No-Twining
Slightly Twining
Moderately Twining
Twining
Very Twining
Length of the main vines
| Code | Term | Description |
|---|---|---|
| 3 | Erect | <75 cm |
| 5 | Semi-Erect | 75-150 |
| 7 | Spreading | 151-250 cm |
| 9 | Extremely spreading | > 250 cm |
Estimated percentage of the ground cover recorded 35-40 days after planting
| Code | Term | Description |
|---|---|---|
| 3 | Low | <50% |
| 5 | Medium | 50-74% |
| 7 | High | 75-90% |
| 9 | Total | >90% |
Average length of at least three internodes located in the middle section of the vine.
Legend:
Very short <3 cm
Short 3-5 cm
Intermediate 6-9 cm
Long 10-12 cm
Very long >12 cm
Average diameter of at least three internodes located in the middle section of the vine.
Legend:
Very thin <4 mm
Thin 4-6 mm
Intermediate 7-9 mm
Thick 10-12 mm
Very thick >12 mm
Anthocyanine (purple pigmentation) present in the vines beside the green colour. The predominant colour should be evaluated considering the whole vine from base to tip.
Legend:
Green
Green with fee purple spots
Green with many purple spots
Green with many dark purple spots
Mostly purple
Mostly dark purple
Totally purple
Totally dark purple
Anthocyanine (purple pigmentation) present in the vines beside the green colour. The predominant colour should be evaluated considering the whole vine from base to tip. The secondary colour is more easily evaluated using younger vines.
| Code | Term | Description |
|---|---|---|
| 0 | Absent | |
| 1 | Green base | |
| 2 | Green tip | |
| 3 | Green nodes | |
| 4 | Purple base | |
| 5 | Purple tip | |
| 6 | Purple nodes |
Degree of hairiness of immature leaves recorded at the apex of the vines
Legend:
Absent
Sparse
Moderate
Heavy
Described from mature leaves located in the middle section of the vine.
| Code | Term | Description |
|---|---|---|
| 1 | Rounded | |
| 2 | Reniform | Kidney-shaped |
| 3 | Cordate | Heart-shaped |
| 4 | Triangular | |
| 5 | Hastate | Trilobular and spear-shaped, with the basal lobes more or less divergent |
| 6 | Lobed | |
| 7 | Almost divided |
Legend:
No lateral lobes Entire
Very slight Teeth
Slight
Moderate
Deep
Very deep
Most leaves of sweet potato have two basal lobes and they should not be counted. Record the predominant number of the lateral and central leaf lobes observed on the leaves located in the middle of section of the vine.
Generally sweet potatoes have 1,3,5,7 or 9 leaf lobes. If the leaf has no lateral lobes but shows a central tooth this number is 1. If the apical portion of the leaf is totally rounded this number is 0.
| Code | Term | Description |
|---|---|---|
| 0 | Absent | |
| 1 | Toothed | |
| 2 | Triangular | |
| 3 | Semi-circular | |
| 4 | Semi-elliptic | |
| 5 | Elliptic | |
| 6 | Lanceolate | |
| 7 | Oblanceolate | |
| 8 | Linear | Broad |
| 9 | Linear | Narrow |
Length from the basal lobes to the tip of the leaves. Record the average expression of at least 3 leaves located in the middle section of the vine.
| Code | Term | Description |
|---|---|---|
| 3 | Small | < 8 cm |
| 5 | Medium | 8-15 cm |
| 7 | Large | 16-25 cm |
| 9 | Very large | > 25 cm |
Describe the most frequent expression of the distribution of anthocyanin (purple) pigmentation shown in the veins of the leaves lower surface
| Code | Term | Description |
|---|---|---|
| 1 | Yellow | |
| 2 | Green | |
| 3 | Purple spot in the base of mian rib | |
| 4 | Purple spots in several veins | |
| 5 | Main rib partially purple | |
| 6 | Main rib is mostly or totally purple | |
| 7 | All veins partially purple | |
| 8 | All veins mostly or totally purple | |
| 9 | Lower surface and veins totally purple |
Describe the overall foliage colour considering the colour of the fully expanded mature leaves of several plants. The variegation in leaf colour due to virus symptoms should not be recorded.
| Code | Term | Description |
|---|---|---|
| 1 | Yellow-green | |
| 2 | Green | |
| 3 | Green wiith purple edges | |
| 4 | Greyish-green | Due to heavy pubescence |
| 5 | Green with purple veins on upper surface | |
| 6 | Slightly purple | |
| 7 | Mostly purple | |
| 8 | Green upper, purple flower | |
| 9 | Purple both surface |
Describe the overall foliage colour considering the colour of the fully expanded immature leaves of several plants. The variegation in leaf colour due to virus symptoms should not be recorded.
| Code | Term | Description |
|---|---|---|
| 1 | Yellow-green | |
| 2 | Green | |
| 3 | Green wiith purple edges | |
| 4 | Greyish-green | Due to heavy pubescence |
| 5 | Green with purple veins on upper surface | |
| 6 | Slightly purple | |
| 7 | Mostly purple | |
| 8 | Green upper, purple flower | |
| 9 | Purple both surface |
Average petiol length, from the base to the insertion with the blade, of at least 3 leaves in the middle portion of the main vine.
| Code | Term | Description |
|---|---|---|
| 1 | Very short | <10 cm |
| 3 | Short | 10-20 cm |
| 5 | Intermediate | 21-30 cm |
| 7 | Long | 31-40 cm |
| 9 | Very long | >40 cm |
Distribution of the anthocyanin (purple) pigmentation in the petioles of leaves. Indicate the most predominant colour first
| Code | Term | Description |
|---|---|---|
| 1 | Green | |
| 2 | Green with purple near stem | |
| 3 | Green with purple near leaf | |
| 4 | Green with purple at both ends | |
| 5 | Green with purple spots throughout the petiole | |
| 6 | Green with purple stripes | |
| 7 | Purple with green near leaf | |
| 8 | Some petiole purple, others are green | |
| 9 | Totally pr mostlry purple |
Storage root outline shown in longitudinal section.
| Code | Term | Description |
|---|---|---|
| 1 | Round | Almost a circular outline with a length to a breadth (L/B) ratio of about 1:1 |
| 2 | Round elliptic | a alightly circular outline with acute ends, and L/B ratio not more than 2:1 |
| 3 | Elliptic | symmetrical outline with about the maximum breadth at equal distance from both ends which are slightly acute. L/B ratio not more than 3:1 |
| 4 | Ovate | outline resembling the longitudinal section of an egg. The broadest part is at the distal end (away from the root stalk) |
| 5 | Obvoate | inversely ovate outline. The broadest part is at the proximal end (i.e. close to the root stalk) |
| 6 | Oblong | almost rectangular outline with with sides nearly parallel and corners rounded. L/B ratio is 2:1. |
| 7 | Long Oblong | oblong outline with with a L/B ratio about 2:1 |
| 8 | Long elliptic | elliptic outline with a L/B ratio of more than 3:1 |
| 9 | Long irregular or curved |
| Code | Term | Description |
|---|---|---|
| 0 | Absent | |
| 1 | Alligator-like skin | |
| 2 | Veins | |
| 3 | Shallow horizontal constrictions | |
| 4 | Deep horizontal constrictions | |
| 5 | Shallow longitidnal grooves | |
| 6 | Deep longitudinal grooves | |
| 7 | Deep constrictions and deep grooves |
| Code | Term | Description |
|---|---|---|
| 1 | Very thin | < 1 mm |
| 3 | Thin | 1-2 mm |
| 5 | Intermediate | 2-3 mm |
| 7 | Thick | 3-4 mm |
| 9 | Very thick | > 4mm |
| Code | Term | Description |
|---|---|---|
| 1 | White | |
| 2 | Cream | |
| 3 | Yellow | |
| 4 | Orange | |
| 5 | Brownish orange | |
| 6 | Pink | |
| 7 | Red | |
| 8 | Purple-red | |
| 9 | Dark-purple |
| Code | Term | Description |
|---|---|---|
| 1 | Pale | |
| 2 | Intermediate | |
| 3 | Dark |
| Code | Term | Description |
|---|---|---|
| 0 | Absent | |
| 1 | White | |
| 2 | Cream | |
| 3 | Yellow | |
| 4 | Orange | |
| 5 | Brownish orange | |
| 6 | Pink | |
| 7 | Red | |
| 8 | Purple-red | |
| 9 | Dark-purple |
| Code | Term | Description |
|---|---|---|
| 1 | White | |
| 2 | Cream | |
| 3 | Dark cream | |
| 4 | Pale yellow | |
| 5 | Dark yellow | |
| 6 | Pale orange | |
| 7 | Intermediate orange | |
| 8 | Dark orange | |
| 9 | Strongly pigmented with anthocyanine |
| Code | Term | Description |
|---|---|---|
| 0 | Absent | |
| 1 | White | |
| 2 | Cream | |
| 3 | Yellow | |
| 4 | Orange | |
| 5 | Brownish orange | |
| 6 | Pink | |
| 7 | Red | |
| 8 | Purple-red | |
| 9 | Dark-purple |
| Code | Term | Description |
|---|---|---|
| 0 | Absent | |
| 1 | Narrow ring in cortex | |
| 2 | Broad ring in cortex | |
| 3 | Scattered spots in the flesh | |
| 4 | Narrow ring in flesh | |
| 5 | Broad ring in the flesh | |
| 6 | Ring and other areas in the flesh | |
| 7 | In longitudinal sections | |
| 8 | Covering most of the flesh | |
| 9 | Covering all the flesh |
Legend:
None
Sparse
Moderate
Profuse
| Code | Term | Description |
|---|---|---|
| 1 | White | |
| 2 | White limb with purple throat | |
| 3 | White limb with pale purple ringa nd purple throat | |
| 4 | Pale purple limb with purple throat | |
| 5 | Purple |
Legend:
Semi-stellate
Pentagonal
Rounded
| Code | Term | Description |
|---|---|---|
| 1 | Outer two shorter | |
| 2 | Equal |
Number of veins observed in sepals. Record the most requent number in ten typical flowers
Legend:
Ovate
Elliptic
Obovate
Oblong
Lanceolate
| Code | Term | Description |
|---|---|---|
| 1 | Acute | |
| 3 | Obtuse | |
| 5 | Acuminate | |
| 7 | Caudate |
Legend:
Absent
Sparse
Moderate
Heavy
| Code | Term | Description |
|---|---|---|
| 1 | Green | |
| 2 | Green with purple edge | |
| 3 | Green with purple spots | |
| 5 | Green with purple areas | |
| 6 | Some sepals are green, others purple | |
| 7 | Totally pogmented - pale purple | |
| 9 | Totally pigmented - dark purple |
Legend:
White
Pale purple
Purple
| Code | Term | Description |
|---|---|---|
| 1 | White | |
| 3 | White with purple at the base | |
| 5 | White with purple at the top | |
| 7 | White with purple spots throughout | |
| 9 | Purple |
The relative position of the stigma as compared to the highest anther.
Legend:
Inserted Shorter than longest anther
Same height as highest anther
Slightly exerted
Exerted Longer than longest anther
Legend:
None
Scarce
Sparse
Moderate
Profuse
Arrangement of the storage roots on the underground stems.
Legend:
Closed cluster
Open cluster
Dispersed
Very dispersed
Length of the stalk joining the storage roots to the stems
| Code | Term | Description |
|---|---|---|
| 0 | Sessile or absent | |
| 1 | Very short | < 2 cm |
| 3 | Short | 2-5 cm |
| 5 | Intermediate | 6-8 cm |
| 7 | Long | 9-12 cm |
| 9 | Very long | > 12 cm |
Average of ten plants
Legend:
Uniform
Slightly variable
Moderately variable
Legend:
Uniform
Slightly variable
Moderately variable
Average cracking shown in ten plants. Consider all cracks caused by growth and/or water stress. Specify reference or reference cultivar
Legend:
Absent
Few cracks
Medium number of cracks
Many cracks
Amount of latex observed after cross sectioning medium-sized storage roots
Legend:
Little
Some
Abundant
Amount of browning due to oxidation observed 5-10 seconds after storage roots are cut in cross. Sepicify in reference or reference cultivar
Legend:
Little
Some
Abundant