moupinensis (French.) Cardot
The plants and fruit of this species are very similar to F. nilgerrensis. The leaves are trifoliate, serrate, elongated oval, with the lower leaflets being smaller. Petioles, runners and peduncles are covered with thickly spreading hairs (Lei et al., 2014). The inflorescence is longer than the leaf petioles and has only two to four flowers. Runners are short monopodial branching. The fruit are orange-red coloured, oval-globose, globose or elliptic, with deeply set achenes, and the flesh is spongy and nearly tasteless. Distribution is in south-west China.
Fragaria tibetica Staudt & Dickoré
This species is approximately 5–15 cm tall and its leaves are pinnately quinquefoliolate or trifoliate and nearly sessile, elliptic with a cuneate apex (Lei et al., 2014). Petioles, runners and peduncles are covered with appressed or ascending hairs. Runners are monopodial branching. There are few flowers per inflorescence, most often two. Fruit are orange-red to light red, oval-globose, globose or elliptic. Seeds are sunken on the shaded side of fruit but not on the sunny side of fruit. Distribution is in south-west China.
Hexaploids (2n = 6x = 42)
Fragaria moschata Duch.
The musky strawberry is a dioecious, tall, vigorous plant that produces few runners. It is native to central Europe, and grows in forests, under shrubs and in tall grass. Leaves are large, dark green, rugose, rhombic, prominently veined and pubescent. The flowers are large (20–25 cm in diameter) and the inflorescence emerges above the foliage, but due to the weight of the ripe berries the scapes lie along the ground. The calyx is usually reflexed. Its stolons are sympodial branching. The fruit is light red to dull-brownish to purplish-red, soft, irregular-globose to ovoid and has a strong vinous flavour. The fruit is slightly larger than that of F. vesca and bears raised achenes. The calyx is strongly reflexed. Both white and red, perfect-flowered forms are cultivated to a limited extent under the name hautboy or hautbois.
Octoploids (2n = 8x = 56)
Fragaria chiloensis (L.) Duch.
The beach or Chilean strawberry was once extensively cultivated in western South America and France but is now only grown to a limited extent (see Chapter 2, this volume). Plants are low-spreading and vigorous with prolific runnering (Fig. 1.5), and they tend to be evergreen. Flowers are large, 20–35 mm in diameter. Leaves are generally thick, strongly reticulate-veiny beneath, dark green and very glossy. Runners are robust and bright red. Native forms have fruit that is dull to bright red in colour, with white flesh and mild to pungent flavour. Achenes are reddish-brown to dark brown. Many of the cultivated forms are albino. Fruit is round to oblate with raised or sunken achenes. Fruit size in the cultigens can be in excess of 10 g, but most native forms average 1–3 g.
Fig. 1.5. Duchesne’s drawing of Fragaria chiloensis. This species is one of the progenitors of the cultivated species Fragaria × ananassa. (From Darrow, 1966.)
Wild populations of F. chiloensis are either dioecious, gynodioecious or perfect flowered depending on geographical location. North American F. chiloensis are primarily dioecious, with staminate plants being about 10% more common than pistillate (Hancock and Bringhurst, 1979b, 1980). In some cases, apparent males are polygamodioecious and bear a few early fruits. Highly fertile hermaphrodites have been found in California at Año Nuevo and Pigeon Point, Alaska, and in the northern islands off the coast of British Columbia. In Chile, F. chiloensis is largely gynodiecious as all wild plants are either pistillate or hermaphroditic (Lavín, 1997). Plants in Hawaii are all hermaphroditic.
There are four subspecies of F. chiloensis recognized (Staudt, 1989): (i) ssp. lucida (E. Vilmorin ex Gay) Staudt – coast of Pacific Ocean from Queen Charlotte Island to San Luis Obispo, California; (ii) ssp. pacifica Staudt – coast of Pacific Ocean from Aleutian Islands to San Francisco, California; (iii) ssp. sandwicensis (Degener and Degener) – Hawaii; and (iv) ssp. chiloensis (L.) Duch. – beaches and mountains of South America. Two forms of this subspecies are recognized, the cultivated f. chiloensis and the native f. patagonia.
It is believed that the aboriginal people of Chile (Mapuche and Picunche) were the domesticators of F. chloensis ssp. chiloensis f. chiloensis about 1000 years ago and they grew them in small garden plots in coastal areas between latitudes 35°S and 39°S (see Chapter 2, this volume). Consistent with a domestication bottleneck, intersimple sequence repeat (ISSR) genetic diversity in f. chiloensis (Percentage of polymorphic bands (P) = 48%, Nei’s genetic index (h) = 0.12, Shannon’s information index (S) = 0.19) was found to be half of that in f. patagonica (P = 90%, h = 0.25, S = 0.38) (Carrasco et al., 2007).
Recent morphometric and random amplified polymorphic DNA (RAPD) analyses of interspecific variation in F. chiloensis have indicated that ssp. lucida and pacifica might intergrade too much to be considered separate subspecies, but ssp. sandwicensis and chiloensis are distinct (Catling and Porebski, 1998). The major characteristics used to separate the subspecies were hair length, leaflet size, plant colour, petal number and whether the hairs on the leaf stalk were ascending or spreading. Hair orientation was the only reliable way to distinguish ssp. lucida from pacifica.
Several ecotypes of F. chiloensis have been identified in both North and South America. Distinct dune, coastal-strand, headland-scrub and woodland-meadow types are found in California (Table 1.2). They are distinguished primarily by flower number, leaf width, leaf biomass, runner width and resistance to salt and drought stress. The woodland-meadow types may be stabilized hybrid derivatives of F. chiloensis × F. virginiana (Hancock and Bringhurst, 1979b). At least two distinct native races have been described in Chile: a coastal type with dark, more glossy, green leaves, and a higher-elevation form with duller leaves and a blue casting, much like F. virginiana ssp. glauca (Cameron et al., 1993). In a morphometric analysis of Chilean F. chiloensis, del Pozo and Lavin (2005) identified four cluster groups among wild accessions, although they did not specify any climatic or regional patterns to the variability. The most diagnostic characteristics were leaflet size, plant size, weight of fruit and fruit size. Interestingly, white forms of native F. chiloensis were discovered that clustered very closely to the white, much larger-fruited domesticated forms (Fig. 1.6).
Fig. 1.6. Distribution of 61 Chilean accessions of strawberry on the first and second principal components (PC1 and PC2) of a multivariate analysis of morphological traits. Symbols represent accessions of: wild Fragaria chiloensis f. patagonica with red fruit (●); wild F. chiloensis f. patagonica with
