Populational change in flowering time caused by different harvesting date observed in a late-summer type cultivar Miyazakizairai of buckwheat (Fagopyrum esculentum Moench).

Evaluation of Cultivar Differences in Preharvest Sprouting of Common Buckwheat (Fagopyrum esculentumMoench)

“…Summer ecotype cultivars of buckwheat are considered to have differentiated from the latesummer ecotype (Minami and Namai, 1986;Iwata et al, 2005). Cultivated species are generally under automatic selection pressure to lose dormancy (Harlan et al, 1973).…”

“…There is accumulating evidence that QTL of domestication-related traits are clustered close together on the same linkage group (Koinange et al, 1996;Takeuchi et al, 2003;Gu et al, 2005;Hancock, 2005). In buckwheat, summer ecotype cultivars are considered to have differentiated from the late-summer ecotype cultivars as a result of adaptation to the long-day condition of summer cropping in high latitude regions (Minami and Namai, 1986). Therefore, selection pressure on photosensitivity may have induced loss of seed dormancy of summer ecotype buckwheat cultivars, due to genetic linkage between photosensitivity and seed dormancy.…”

Varietal Differences of Flood Tolerance during Germination and Selection of the Tolerant Lines in Common Buckwheat

“…Minami and Namai (1986) suggested that the summer cultivars differentiated from the latesummer cultivars under natural and artifi cial selection for early-fl owering types under long-day conditions during the adaptation to summer cropping in highlatitude regions. This view is supported by the fi nding of Iwata et al (2005) that the intracultivar diversity of SSR markers in common buckwheat signifi cantly and positively correlated with the fl owering period.…”

“…Minami and Namai (1986), and Iwata et al (2005) suggested that the summer agroecotypes differentiated from late-summer cultivars under natural and artifi cial selection of early-fl owering types under long-day conditions during the adaptation of this species to summer cropping in high-latitude regions. Although intracultivar diversity of summer-agroecotype cultivars, based on simple-sequence repeat (SSR) markers was lower than that of cultivars of other agroecotypes (Iwata et al, 2005), the decrease of the diversity through differentiation of fl ood tolerance remains unknown.…”

Important agronomic characteristics of yielding ability in common buckwheat; ecotype and ecological differentiation, preharvest sprouting resistance, shattering resistance, and lodging resistance

“…Based on these studies, Sugawara (2001) proposed that the flowering of common buckwheat is influenced by temperature but is dominated primarily by photoperiod, and that ecotype differentiation depends on reactivity to photoperiod: i.e., natural selection Ujihara 1979, Ujihara andMatano 1978) and artificial selection (Minami and Namai 1986) were due primarily to differences in photoperiod in the culture season as the cultivation area of the autumn ecotype population spread northwards in the Japanese archipelago. In this proposal the summer ecotype is derived from the autumn ecotype.…”