AAC Champlain

Lettuce

Variety Description

Varieties used for comparison: 'Ithaca' and 'Hochelaga'

Summary: 'AAC Champlain' has a leaf shape that is tranverse narrow elliptic while 'Ithaca' has a circular to transverse broad elliptic leaf shape and 'Hochelaga' has a circular shaped leaf. Under long day conditions, 'AAC Champlain' bolts later than 'Ithaca'. At flowering, the plants of 'AAC Champlain' are shorter than the reference varieties. The incidence and severity of tipburn in 'AAC Champlain' is less than in 'Hochelaga'.

Description:

PLANT TYPE: closed head lettuce

SEEDLING: very weak to weak anthocyanin colouration

LEAF: entire leaf blade division at the 10 to 12 leaf stage, medium thickness, erect to semi-erect attitude at harvest maturity, transverse narrow elliptic shape, obtuse tip, light to medium green colour, no anthocyanin colouration, medium glossiness of upper side, weak to medium blistering, small blisters, medium to strong degree of undulation of margin, strong degree of incisions on apical part, medium density of shallow dentate incisions, fan shaped venation, absent or very weak axillary sprouting

HEAD: strong degree of overlapping of upper part of leaves, dense, circular in longitudinal section, medium to late beginning of bolting under long day conditions, early harvest maturity

SEED: black

Origin & Breeding History: 'AAC Champlain' originates from the cross made during November 2001 between the F4 lines X3/15-M-23-18-17 as the female parent and X-156-M-126-58 as the male parent, in the greenhouses of the Agriculture & Agri-Food Canada Horticultural Research & Development Centre in Saint-Jean-sur-Richelieu, Quebec. The female parental line was derived from a SouthBay / Salinas cross made in April 1998 and the male parental line from a Summertime / Eldorado cross made in September 1998. A single plant selection was made using the pedigree method and given the designation X1457.

The F1 seed was planted in the greenhouses in late December 2001 with the F2 seed being collected in May of 2002. F2 seedlings of X1457-M were planted on a muck soil farm in Napierville, Quebec for evaluation during the summer of 2002. Two F2 plants were selected for Great Lakes character combined with good size, short core, good head configuartion, low ribbiness and lack of rib discolouration and tipburn symptoms. In the fall of 2002, 337 F3 seeds were collected from one (#873) of the two selections which regenerated through in vitro culture. F3 seedlings of X1457-M-873 were planted at the AAFC Sainte-Clotilde experimental station in the spring of 2003. Mature plants were evaluated and two plants were selected for their short core, good size, and excellent leaf configuration. One of the selections (#720) was regenerated using in vitro culture and produced 675 F4 seed. F4 seedlings of X1457-M-873-720 were transplanted and evaluated at four planting sites in Quebec during the summer of 2004. On the 24 selections collected, 14 were successfully regenerated through in vitro culture of which one (#556) was selected producing 600 F5 seed. In 2005, F5 seedlings were transplanted and evaluated at four planting sites. Four selections were collected of which two survived. One (#553) of them produced 1100 F6 seed. In 2006, single plant selection continued on F6 plants evaluated at four planting sites in Quebec. During that same year, F6 seed were planted in single plant progeny rows in the San Joaquin Valley, California in April for seed evaluation and multiplication. Ten single plants were selected and F7 seed collected from each plant with the rest of the plants being bulk massed after harvest in September 2006. X1457-M-873-720-556-553 was trialed from 2007-2009 in introduction plantings. In 2009 it was designated 'QSJ-09' and was later renamed 'AAC Champlain'.

Tests & Trials: Tests and trials were conducted at the JPL Guerin Farm in Sherrington, Quebec in the summers of 2010 and 2011. Plots consisted of 80 plants separated into 2 rows that were 14.6 meters long and spaced 91 centimeters apart. Plants were spaced 35.5 centimeters apart within the row. There were 4 replications arranged in a RCB design. LSD values in the table are at the 0.05 level. LSD value for the severity of tipburn were applied on square root transformed data in parentheses to respect normality and homoscedasticity.

Comparison tables for 'AAC Champlain' with reference varieties 'Ithaca' and 'Hochelaga'

Plant height in flower (cm)

Incidence of tipburn (% of plants)

Severity of Tipburn

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Lettuce: 'AAC Champlain' (left) with reference varieties 'Ithaca' (centre) and 'Hochelaga' (right)

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Lettuce: 'AAC Champlain' (left) with reference varieties 'Ithaca' (centre) and 'Hochelaga' (right)