This Minimum List of Descriptors for East African Highland Bananas was developed for the MusaNet East and Southern African Regional Workshop on EAHB Characterization and Documentation at NARO, Mbarara, Uganda in December 2016. It is a compilation of descriptors from the Minimum List of Descriptors for Musa plus several descriptors that are highly discriminating for EAHBs from the 1996 Descriptors for Banana book as identified by Deborah Karamura, Kodjo Tomekpe, the Expert Team of the Organization Committee of the workshop and the East African banana curators.
For any question, remark or feedback on these guidelines, please contact Rachel Chase (r.chase@cgiar.org) or Nicolas Roux (n.roux@cgiar.org).
The best time to take photos and document
Vegetative descriptors at shooting or within 15 days of shooting. During this time, maximum development of vegetative parts takes place.
Bunch and fruit descriptors are when the fruit are green-ripe or yellowing (“harvest time”). This is separate from the instance of a single ripe fruit generally observed on the first or the second hand of the bunch. Also, do not confuse harvest time with ripe fruit affected by diseases, insect bites or birds.
For all colour descriptors, colour should be determined with the appropriate colour chart (A or B) and out of direct sunlight. The best time to observe colour descriptors is in the morning when the light is clearer than in the afternoon. For the fruit descriptors (6.7.1 - 6.7.7) observation must be done on several fruits in order to reflect the dominant case.
Taxonomic Advisory Group (TAG) 2017. Minimum Descriptor List for East African Highland Bananas. Bioversity International, Montpellier, France.
Height recorded from the base of the pseudostem to the emerging point of the peduncle. Girth measured at lower levels of the pseudostem around 20 cm above the collar.
| Code | Term | Description |
|---|---|---|
| 1 | <4.1 | |
| 2 | 4.1 - 5.1 | |
| 3 | > 5.1 |
(Outermost sheaths)
| Code | Term | Description |
|---|---|---|
| 1 | None | |
| 2 | Brown/rusty brown | |
| 3 | Black | |
| 4 | Other |
| Code | Term | Description |
|---|---|---|
| 1 | Suckers start with tubular leaves | |
| 2 | Suckers don't have tubular leaves |
| Code | Term | Description |
|---|---|---|
| 1 | Far from parent plant | Emerging >50 cm from parent plant |
| 2 | Close to parent | Vertical growth |
| 3 | Close to parent | Growing at an angle |
Record the relative surface area coverage by blotches. Look at several plants if possible to get an overall idea. Observe at lowering time.
| Code | Term | Description |
|---|---|---|
| 1 | No pigmentation | |
| 2 | Sparse blotching | <20% |
| 3 | Moderate blotching | 20%-50% |
| 4 | Extensive pigmentation | >50% |
| Code | Term | Description |
|---|---|---|
| 1 | Not twisted | |
| 2 | Twisted |
Observe only the part of the rachis between the last hand and the male bud.
| Code | Term | Description |
|---|---|---|
| 1 | Falling vertically | |
| 2 | At an angle | |
| 3 | With a curve | |
| 4 | Horizontal or supra-horizontal | |
| 5 | Erect |
Observe only that part of the rachis between the last hand of fruit and the male bud.
| Code | Term | Description |
|---|---|---|
| 1 | Bare | |
| 2 | Neutral flowers on one to few hands only near the bunch | (rest of stalk is bare). |
| 3 | Male flowers/bracts above the male bud | (rest of stalk is bare) |
| 4 | Neutral/male flowers and presence of withered bracts on the entire stalk. | |
| 5 | Neutral/male flowers on the whole stalk without persis. bracts | (still firmly attached to rachis) |
| 6 | Small bunch from neutral/hermaphrodite flowers just above the male bud | (which gradually falls) |
| 7 | Some hermaphrodite flowers remaining in the centre of the rachis. | |
| 8 | Other |
“w” is the broadest width of the male bud. “x” is the length from the base of the male bud to the point of broadest width ‘w’; “y” is the total length of the male bud. As the figure shows, these parameters express the profile of the bud. Do not measure the dimensions along the bud but rather on a projection/outline of the bud (e.g. trace the outline of the bud on paper). Calculate the ratio w/y (see figure)
| Code | Term | Description |
|---|---|---|
| 1 | Skinny | w/y <= 0.45 |
| 2 | Medium | 0.45 < w/y < 0.55 |
| 3 | Fat | w/y >= 0.55 |
“w” is the broadest width of the male bud. “x” is the length from the base of the male bud to the point of broadest width ‘w’; “y” is the total length of the male bud. As the figure shows, these parameters express the profile of the bud. Do not measure the dimensions along the bud but rather on a projection/outline of the bud (e.g. trace the outline of the bud on paper). Measure the length (y) of male bud at harvest (see figure).
| Code | Term | Description |
|---|---|---|
| 1 | Short | y <= 20 cm |
| 2 | Medium | 20 cm < y < 30 cm |
| 3 | Long | >= 30 cm |
“w” is the broadest width of the male bud. “x” is the length from the base of the male bud to the point of broadest width ‘w’; “y” is the total length of the male bud. As the figure shows, these parameters express the profile of the bud. Do not measure the dimensions along the bud but rather on a projection/outline of the bud (e.g. trace the outline of the bud on paper). Calculate the ratio x/y (see figure).
| Code | Term | Description |
|---|---|---|
| 1 | High shouldered | x/y <= 0.28 |
| 2 | Medium shouldered | 0.28 < x/y < 0.30 |
| 3 | Low shouldered | x/y >= 0.30 |
Refers to the first external unlifted bract. Flatten bracts to determine shape.
| Code | Term | Description |
|---|---|---|
| 1 | Pointed | |
| 2 | Intermediate | |
| 3 | Obtuse | |
| 4 | Obtuse and split |
Alignment of bracts at the apex of the male bud
| Code | Term | Description |
|---|---|---|
| 1 | Convolute | |
| 2 | Moderately imbricate | |
| 3 | Highly imbricate |
Angle between the axis of the bunch and the vertical.
| Code | Term | Description |
|---|---|---|
| 1 | Hanging vertically | |
| 2 | Slightly angled | |
| 3 | Hanging at a 45° angle | |
| 4 | Horizontal | |
| 5 | Erect |
The bunch should still be on the plant.
| Code | Term | Description |
|---|---|---|
| 1 | Very Lax | (one can easily place a hand horizontally between the hands of fruit) |
| 2 | Lax | (one can easily place one's hand BETWEEN the hands OF fruit) |
| 3 | Compact | (one can place one's finger, but NOT one's hand, between the hands of fruit) |
| 4 | Very compact | (one cannot place one's finger BETWEEN the hands OF fruit) |
Recorded only on the fruits arranged symmetrically around the stalk. Observe the general appearance.
| Code | Term | Description |
|---|---|---|
| 1 | Curved towards stalk | |
| 2 | Parallel to the stalk | |
| 3 | Curved upward | (obliquely, at a 45° angle upward) |
| 4 | Perpendicular to the stalk | |
| 5 | Other |
Length measured as the internal arc of the fruit, without pedicel. Circumference measured around the middle of the fruit. Record on the inner fruit in the middle of the mid-hand of the bunch. If there is an even number of hands, there will be two middle hands. Count the middle hand that developed first.
| Code | Term | Description |
|---|---|---|
| 1 | < 3.1 | |
| 2 | 3.1 - 4.0 | |
| 3 | > 4.0 |
| Code | Term | Description |
|---|---|---|
| 1 | Pointed | |
| 2 | Lengthily pointed | like plantain |
| 3 | Blunt tipped | plateau at tip |
| 4 | Strongly bottle necked | wider under tip than number 2 |
| 5 | Rounded |
Observe before cutting the bunch as relicts may fall off.
| Code | Term | Description |
|---|---|---|
| 1 | Without flower relicts | |
| 2 | Few flower relicts (<20% of the fruits with relicts) | |
| 3 | Persistent flower relicts (>20% of the fruits with relicts) | |
| 4 | Only base of the style persists |