RC Tecumseh

Switchgrass

Variety Description

Variety used for comparison: 'Summer'

Summary: At panicle emergence, the plants of ‘RC Tecumseh' have fewer tillers than the plants of ‘Summer'. At the end of anthesis, the stem at the midpoint of the internode below the penultimate leaf and at the midpoint of the 3rd internode from the bottom of the plant for ‘RC Tecumseh' is broader than those of ‘Summer'. At the soft dough stage, the penultimate leaf of ‘RC Tecumseh' is longer and wider than that of ‘Summer'. At maturity, the plants of ‘RC Tecumseh' are taller than the plants of ‘Summer'.

Description:

PLANT: tetraploid, agricultural or conservation utilization, panicles emerge early to mid-season, erect growth habit at panicle emergence, medium to high number of vegetative and reproductive tillers, matures early to mid-season

FLAG LEAF: erect to semi-erect attitude
LEAF BLADE: yellow-green on upper side, medium width at widest point

STEM: many internodes
INTERNODE (BELOW PENULTIMATE LEAF): medium thickness at mid-section
INTERNODE (3RD INTERNODE FROM BOTTOM OF PLANT): medium thickness at mid-section

PANICLE: medium to long

Origin & Breeding History: ‘RC Tecumseh' was developed using Recurrent Restricted Phenotypic Selection breeding technique over 6 breeding cycles. Seed harvested in 1992 from the switchgrass variety ‘Summer' was sown in cell trays in a greenhouse, with seedlings thinned to 1 per cell based on early emergence and seedling vigor. One thousand selected seedlings were transplanted into an outdoor crossing block in Tavistock, Ontario in 1992. In 1994, negative selection was employed to remove approximately 25% of inferior plant types prior to anthesis and in the fall, the remaining plants were harvested with the resulting seed planted for multiplication at McGill University, Montreal, Quebec in 1996. In 2008, 200 seedlings, from the heaviest seed in the multiplication plots, were selected based on emergence, reduced tillering and vigor and transplanted in a nursery. In 2009, undesirable plant types were removed and seed harvested from plants selected based on maturity, plant height, biomass per tiller, stem thickness, leaf habit, lodging, tiller number and the absence of disease symptoms. This breeding approach was repeated in a third cycle of selection from 2010-2012. Two further cycles of selection occurred in 2013 and 2014 based on seedling vigor. In 2015-2016, a final 6th cycle was undertaken to select for uniform maturity. The resulting harvested seed was used for seed multiplication at the Emile A. Lods Agronomy Research Farm in Sainte-Anne-de-Bellevue, Quebec commencing in 2017.

Tests & Trials: The comparative trials for ‘RC Tecumseh' were conducted by REAP Canada during the 2023 and 2024 growing seasons at the Emile A. Lods Agronomy Research Centre, at the Macdonald Campus of McGill University in Sainte-Anne-de-Bellevue, Quebec. Plots were arranged in a RCB design with 5 replicates per variety per year. Each plot measured 3.0 x 2.4 metres, containing 20 plants, resulting in 100 plants per variety per year. Measured characteristics were based on 50 measurements per variety per year. Mean differences were significant at the 5% confidence probability level based on a post hoc Tukey's Honest Significant Difference Test.

Comparison tables for 'RC Tecumseh' with reference variety 'Summer'

Tiller number (total number of reproductive and vegetative tillers)

Stem width (at the midpoint of the internode below the penultimate leaf) (mm)

Stem width (at the midpoint of the 3rd internode from the bottom of the plant) (mm)

Penultimate leaf length (cm)

Penultimate leaf width (at widest point) (mm)

Plant height (at maturity, including panicle) (cm)

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Switchgrass: ‘RC Tecumseh' (right) with reference variety ‘Summer' (left)

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Switchgrass: ‘RC Tecumseh' (left) with reference variety ‘Summer' (right)