ASIMINA TRILOBA (NORTHERN BANANA)

MINIMUM TEMPERATURE SUPPORTED -20°C

(DATA REFERS TO AN ADULT PLANT IN OPTIMAL HUMIDITY AND SOIL CONDITIONS)

From Wikipedia, the free encyclopedia.

The donkey ( Asimina triloba ( L. ) Dunal ) is a small tree from fruit to leaf deciduous from the family from the Annonaceae . ^[2] It is native to the eastern United States where it is known by the name of pawpaw or paw paw.

It grows wild along the banks of rivers and in the undergrowth forming typical groves clonal which originate over time from the roots of a single individual, a formation which is called the Asimina stain or pawpaw patch.

It belongs to family from the Annonaceae , the same one of which they are part Cherimoya , Graviola And Ylang-ylang , a very widespread species in the tropical belts.

Common names

The name Asimina comes from the term Assimil or Rassimin used by Native Americans , passing by the term Cajun French Asiminier to finally arrive at the form used by the official nomenclature.

The American common name Pawpaw derives from the name of the native Paw Paw tribe, or Pawpaw, understood as "fruit of the Paw Paw".

The curious appearance of the fruit has also led over time to the creation of countless local nicknames which refer to the presumed similarity with the species of the genus Musa , with which it has no relation among which we can find:

wild banana, mountain banana, prairie banana, poor man's banana, Indian banana, West Virginia banana, Kansas banana, Kentucky banana, Michigan banana, Missouri banana, and so on.

Description

The Asimina plant or pawpaw (pronunciation English : [ˈpɔːpɔː] ^[3] ) is a small tree with an ascending habit (taller than wide, if not otherwise pruned), reaches 5–6 meters in height, has large, alternate, lanceolate, deciduous leaves of 15– 20 cm long, hanging, often tomentose (very slightly hairy) on the back, gray bark.

The element of interest in this tree is the fruit, for which selection has only recently begun in order to improve its organoleptic qualities. Wood has no commercial value, while the chemical substances contained in the plant have some interest as a natural insecticide and for their anti-tumor functions ^[4] .

In the places of origin (United States) extensive planting on a larger scale is in place, also as a result of the recent revaluation of this fruit, which is now considered to be of greater value than in the past (it was considered a "wild" fruit), and for the which Americans are now developing an affection towards an element considered peculiar, belonging to their own origins, and to their country.

Flower

The flowers, hermaphrodites , of medium size (1.5–3 cm in diameter), are hanging on a petiole rather developed hairy, they are single, rarely collected in groups, axillary to the leaves, they have rotated symmetry, with three small sepals green with brownish hairiness and six petals ; three internal ones enclosing the sexual parts alternating with three external ones, ajar in the first phase, subsequently the petals are slightly folded outwards; the general conformation of the flower is therefore "bell-shaped", of a reddish-dark brown colour. They hatch in April (in Italy), before the leaves.

The flowers have a very light and almost imperceptible odor, slightly putrid and certainly not pleasant (they are dedicated to attracting insects predators or scavengers, such as flies and others Diptera (fly) of the manure heaps, ants or beetles , which are the pollinating agents). Normally the plant is self-sterile, therefore fertilization occurs only between plants (i.e. individuals, or clones ) different, there are some self-fertile varieties and therefore, in this case a single plant is sufficient. In the absence of pollinating insects (in an urban environment without insects), manual artificial pollination (with a brush) may be useful.

Fruit

The fruits are large berries oval, similar in shape to more or less cylindrical pears, 6–18 cm and more in length, and 3–8 cm wide, sometimes with a slightly lobed shape. The fruits are single or often gathered in groups (the ovaries of the flower are multiple) to form "hands" vaguely similar in structure to those of bananas (hence the local names that associate them, not strictly speaking, with bananas). The weight of the fruits is usually from 50–100 g to 250–400 g and more.

The fruits contain numerous brown seeds, arranged in two rows, very hard, even of considerable size (up to 2–3 cm long), similar to large elongated beans. The pulp of the fruit has a dense, firm, creamy consistency, white, or sometimes yellowish in colour, it is sweet and fragrant, with a complex flavor and no acidity, while when the fruit is immature it has an acrid and astringent flavour. The pulp of the fruit is also rich in vitamins and mineral salts, has an unusually high quantity of proteins (since it is fruit).

The fruit ripens in late summer or autumn, from the end of August to September (October in colder countries); given that the flowers do not open all together but over a period of more than a month, the fruits also gradually reach maturity over a period of 30-45 days.

The delayed ripening over time and the delicacy of the fruits (they bruise easily) make industrial cultivation difficult.

Distribution and habitat

The plant is native to the eastern region of the United States in the area that includes the Basin of Mississippi .

It is found wild in the mountain valleys Appalachia , and has a distribution ranging from Nebraska to the west, to the Atlantic Ocean at East; from the South Carolina as the southern limit to the south of Canada , along the banks of the Great Lakes , as the northern limit.

Within its range of origin, many localities take the name of 'paw paw' due to the presence of Asimina plants, the same name is also used in the names of schools since the fruit was very popular with children who went to collect it in the woods at the end of summer.

Ecology

Asimina is widespread in the undergrowth of forest formations with tall trees such as oaks and walnuts of the genus Carya .

It reproduces clonally by enduring low ambient light until a breach is opened in the forest canopy. Once it reaches brighter positions, fruiting begins. The Asimina tends to disappear in closed and too dense woods while it remains for a long time (millennia) in the form of a thicket of suckers in environments that are subject to occasional disturbance actions such as, for example, the banks of rivers.

storage

On a global scale, the Asimina ( Asimina triloba ) has a rating of G5 (very common) in the NatureServe global conservation rank.

In the United States its presence is common (N5) but it is considered an endangered species in the state of New York and an endangered species in New Jersey.

In Canada, where the species is found only in small portions of southern Ontario, the species is classified as vulnerable (S3) and its populations are monitored.

In areas where the population of deer reaches higher densities, it has been noticed how the Asimina tend to become locally more abundant.

This phenomenon is due to the fact that deer routinely consume the seedlings of many tall tree species while ignoring the seedlings of Asimina, also acting as a seed dispersal agent after feeding on the fallen fruit.

History

The current distribution of Asimina in North America is probably due to the dispersal of seeds carried out up to about 10,000 years ago by Megafauna now extinct. The large animals that inhabited the continent became extinct during the Quaternary with the arrival of the first men.

It was then humans who replaced the megafauna as agents of dispersal of the Asimina's seed, activities that continue today.

The first written documentation mentioning Asimina dates back to 1541 in the expedition diaries of Hernando de Soto , who found it among the plants cultivated by the Natives east of Mississippi River .

Several years later the participants in the great expedition of Lewis and Clark they had the opportunity to feed on the fruits of Asimina during their journey into the unknown.

Iced Asimina was 's favorite dessert George Washington And Thomas Jefferson decided to plant Asimina in his residence in Monticello in Virginia .

Cultural importance

It was customary among the inhabitants of the Midwestern countryside to go into the woods at the end of summer in search of the best Asimina patches in which to collect ripe fruits from the ground. The children were particularly skilled in this task and saw the occasion as a game and as a rare opportunity to eat something sweet at will. There are several testimonies of this tradition, including a popular song that we can find in infinite variations throughout the eastern United States: Way down yonder in the pawpaw patch.

In the lyrics of this song, children are invited to follow their playmate who has entered the Asimina grove with the aim of filling the large pockets and bags they carry with them with ripe and fragrant fruits.

Cultivation

The ideal environment for the cultivation of Asimina is the temperate, coastal or continental climate, with relatively hot but not scorching summers, and cold to very cold winters, it resists winter temperatures of −20/−25 °C; the plant requires a dormant period with temperatures below 7 °C to have abundant flowering.

Given the natural environment of origin (alluvial plains or riverbeds of streams or streams, often seasonally subjected to water flow on the surface or underground, with loose and silty soil, rich in debris and plant residues), it is to be considered as a plant suitable for rather humid environments and soils, even if well drained.

The plant prefers soils to pH neutral, or sub-acid (from 5.5 to 7.5), it cannot tolerate calcareous soils. A mulching massive with leaves and plant debris promotes the conservation of pH of the soil adequately low.

The plant has an unusual sensitivity of the roots, their damage, for example during soil cultivation, or during transplanting, seriously damages the plant.

Due to root sensitivity, despite being deciduous, the plant must not be transplanted with bare roots. When transplanting, care should be taken that the clod of earth containing the roots is not disturbed. It is also possible to transplant bare root plants, but in this case it is reasonable to expect high failures (70% of the plants can die) and a certain arrest of growth in the first years of planting.

The best period for planting is during vegetative stasis, in autumn after the leaves have fallen or just after the last frosts, before vegetative awakening.

In this period the root system, more active, reacts more promptly to the stress of the transplant and the risks of its death are reduced.

Due to the substances it contains, the plant is extraordinarily resistant to parasites and diseases, especially in humid environments, and therefore does not require any treatment.

Fruiting usually occurs starting from the third year of flowering, in very rare cases it manages to bear fruit in the first few years.

To accelerate fruiting, it is advisable to grow the plant in areas with a high level of humidity in the environment and soil, with exposure to full sun for a few hours in the spring and summer months. In addition to these environmental factors, it is advisable that the soil is first sprinkled with abundant organic undergrowth debris and then mature stable manure is added.

In the first two years of planting, shade cloths are useful from May to September. The soil is subsequently worked and mulched again on the surface with leaves and organic material from the undergrowth and irrigated in the warmer months. All these factors imitate the habitat of origin of this plant and facilitate fruiting and also growth.

Propagation

Reproduction can be practiced by seed, grafting or root shoots, while the cuttings they usually don't take root. Seeds left to dry quickly lose the ability to germinate, therefore, if not sown immediately upon harvest, they should be buried in moist soil exposed to the winter cold, or kept in a similar environment (refrigerator). Plants obtained from seed do not maintain the characteristics of the plant from which they come: sometimes they can show signs of regression to the wild or a range of new varieties can be obtained, some of which can be of a good standard. Excellent rootstocks can also be obtained with seed reproduction.

Multiplication is easily done only by grafting . Grafted plants bear fruit with certain organoleptic qualities, linked to the grafted variety.

The plant, by its nature, tends to multiply by root shoots. If the sucker comes from the rootstock of a grafted plant, it may bear lower quality or different fruit, as is the plant used as "wild", but it may still be a good pollinator, being a different clone from the graft. Unless you want to experiment (the plant in nature naturally produces "small forests" of suckers), the suckers should be eliminated. Among other things, the sucker, even if rooted, will have little chance of transplanting.

To date, the plant does not appear to be suitable for in vitro multiplication, probably because suitable procedural protocols are lacking ^[5] .

Uses

In addition to the consumption of the fruit, Asimina has also had various other uses over time:

The inner bark of the plant, strong and fibrous, was used by Native Americans and the first settlers of Midwest for preparing ropes, fishing nets, mats and for tying the catch. Asimina logs divided into quarters were used to make fences Arkansas . The hard and shiny seeds of Asimina were carried with them like amulets Ohio since it was believed that they brought good luck, in the same way in which the seeds of the Horse Chestnut are used in Italy.

With the exception of the pulp of the ripe fruits the other parts of the plant are toxic due to the presence of acetogenins with strong anti- mitotic activity, which prevent cell replication and which is why they are being studied for cancer treatment .

In the United States the plant is cultivated in butterfly gardens , (gardens intended for breeding butterflies) due to the fact that it hosts a large swallowtail butterfly with black-white zebra wings ( Eurytides marcellus ) whose caterpillar feeds on the leaves but usually does not cause significant damage to the plant .

Selections

Numerous selections have been made, almost all in the USA, mostly originating from wild plants, but also starting from previous selections. Among the most common:

• Allegheny : Selected by Neal Peterson. Early and very productive plant.
• Belle : Green River Belle or GRB was discovered in Hart County in Kentucky from wild plants. It produces medium sized fruits, firm pulp and good flavour.
• Davis : Selected in 1959 by Corwin Davis, it bears fruit in clusters with very variable sizes (60-300g), oblong can reach up to 12 cm, green skin, yellow pulp, large seeds. Good storage in the refrigerator, ripens at the beginning of September ^[5]
• Georgia : Selected in Italy from Az. Agr. Bella a Rivoli (TO), 150-250g fruits, butter yellow pulp, very aromatic taste, slightly elongated and rounded shape, the skin turns yellow when ripe. It is early, matures from the end of August ( self-fertile )
• Itacha : Selected in Italy by Domenico Montanari, medium-sized fruits (200-300 grams).
• Mango : Selected by Corwin Davis in 1970, strong producer, ripens in early September. Large fruits, orange-yellow pulp with a light mango flavour. ^[5] .
• Mary Foos J .: The pulp has a buttery consistency and colour, contains few seeds, a soft and characteristic aroma, a milky aftertaste, ripens at the beginning of October
• Mitchell : Selected from seeds of a wild plant in Illinois in 1979. Medium sized fruit, pale yellow skin, yellow pulp, few seeds.
• NC-1 : Plant born from a cross between Davis and Overleese. Very vigorous, fruits with thin yellow skin, yellow pulp, sweet and tasty, weighing from 150 to 400g, early ripening, second ten days of September ^[5] .
• Before 1216 : Selected in Italy by Domenico Montanari, Fruits of 200-250g ^[5] rounded oval in shape, butter yellow to ocher pulp, ripe in the second ten days of September ^[5] , ( self-fertile )
• Overleese : Selected by WB Ward , around 1950 from a wild plant in Rushville ( Indiana ) fruits in groups of 3 or 5, each fruit weighing up to 300–350g. Ripens at the beginning of September ^[5] .
• PA Golden : Pennsylvania Golden was selected from seeds in the George Slate collection, by John Gordon, Amherst, ( NY ). Medium fruits, yellow skin, yellow pulp. In the USA, 4 varieties are documented, distinguished by a progressive number from 1 to 4, in Italy only one is marketed.
• Prolific : Selected by Corwin Davis between 1980 - 90. Fairly large fruit (80-250g) with yellow pulp. Ripens in the second ten days of September ^[5] .
• Rappahannock : Selected by Neal Peterson, the plant produces a sweet, aromatic fruit that is very easy to see due to the almost horizontal leaf shape. The seeds are few compared to the pulp (7%).
• Potomac : Selected by Neal Peterson. Large, fleshy fruits with few seeds (4%), intense and sweet aroma.
• Rebecca's Gold : Selected by Corwin Davis in 1974. Kidney-shaped fruit with butter-colored flesh.
• Shenandoah : Overleese hybrid with few seeds (7%), very firm pulp.
• Sunflower : Selected by Milo Gibson around 1970, fruits (often single) weighing 200–250g, butter-yellow pulp with a refreshing flavour, skin that turns yellow when ripe. Ripens in the second ten days of September ^[5] ( self-fertile ).
• Susquehanna : Selected by Neal Peterson. Large fruit, very firm and resistant pulp and peel. Few seeds (4%). Pleasant aftertaste.
• Sweet Alice : Selected by Homer Jacobs in 1934 from wild plant seeds from the Holden Arboretum , Mentor, Ohio. Moderate vigor, compact habit, productive with large, good quality fruit.
• Taylor Selected in 1968 from wild plant seeds by Corwin Davis. Small fruits in groups of up to seven, green skin, yellow pulp, very productive and excellent quality. Ripens at the beginning of September
• Taytwo (also called taytoo): Selected by Corwin Davis. the size of the fruits is very variable (50-300g). Sometimes the peel can blacken, ripening at the beginning of September ^[5] .
• Wabash : Selected in Kentucky by Neal Peterson. Large fruit and few seeds (6%). Sweet taste.
• Wells : Selected from a wild plant in Indiana by David Wells in 1990. Small but tasty fruits (80 - 150g), with green skin and orange interior. Ripens in the second ten days of September.
• Wilson : Selected in Kentucky in 1985, produces average fruit with golden yellow pulp. Ripens at the beginning of September ^[5] .

In 2008 the Kentucky State University Land Grant Program, with the Ohio Pawpaw Growers Association, and the PawPaw Foundation conducted a study to determine which varieties had the best organoleptic qualities ^[6] . Test participants were given samples of 16 varieties of pawpaw without telling them which variety they were tasting, then asking them to rate the sample on a scale from "Terrible" to "Excellent" and indicating whether there was a melon or bitter aftertaste. Although the test was not conducted rigorously (people were not asked to clean their mouths between each tasting, not everyone tasted every sample, no precautions were taken to ensure that the fruit pulp was all the same color, and proposed fruits were probably in a slightly different state of ripeness) the results give a rough indication of which are the best varieties:

Variety\Flavor	Terrible	Bad	Passable	Good	Excellent	Melon aftertaste	Bitter aftertaste	Final score (1-5)
Alleghenies	0	0	4	19	23	9	2	4.41
G9-108	0	0	6	12	22	2	10	4.40
10-35	0	0	4	19	19	3	10	4.36
Shenandoah	0	0	7	16	16	7	12	4.23
NC-1	0	2	5	16	15	4	9	4.16
Potomac	0	0	6	22	12	5	10	4.15
Taytwo	1	1	4	24	13	12	9	4.09
Susquehanna	0	1	13	13	16	8	10	4.02
Wabash	1	0	11	19	14	6	10	4.00
Sunflower	0	2	10	16	13	8	7	3.98
Overleese	0	2	15	15	11	5	15	3.81
Wilson	0	4	11	18	8	9	7	3.73
Jeremy's Gold	0	6	13	19	6	16	7	3.57
3-21	1	4	13	21	4	13	2	3.53
PA Golden	2	4	18	11	7	12	8	3.40
Mitchell	1	16	12	12	3	15	3	3.00