Narrative
WAR 7: LUCERNE
Medicago sativa
'Genesis' syn Y8506
Application No: 1996/091 Accepted: 24 Apr 1996
Applicant: Department of Agriculture for and on behalf of the State of NSW, Orange, NSW.
Agent: South Australian Seedgrowers Co-operative Ltd, Hilton, SA.
Description See Table of comparisons
'Genesis' is a winter-active lucerne for irrigated and dryland pastures. Mean plant height two weeks after the equinox and four weeks after cutting in the first year was 34.5cm (range 16-49). Plant height in spring averaged 29.0cm (range 21-54). Growth habit was generally medium with medium green foliage. Flowering was late with a medium frequency of plants possessing dark blue-violet flowers (45%). There were no plants with variegated, cream, white, or yellow flowers. Stems were long at flowering with a mean of 95.5cm (range 65-126). The percentage of seedlings resistant to phytophthora root rot (Phytophthora medicaginis) and to spotted alfalfa aphids (Therioaphis trifolii f. maculata) was assessed using standard tests as published by the North American Alfalfa Improvement Conference. 'Genesis' was similar to resistant varieties in its response to both phytophthora root rot (61.2% survivors) and spotted aphids (28.0% survivors).
Origin 'Genesis' was bred by the NSW Lucerne Improvement Program at Yanco by RW Williams and RR Young. 'Genesis' originated from a controlled cross between selected plants from breeding lines 'Hely 8' and 'Hely 11' bred by FW Hely, CSIRO, Canberra. These populations were derived from crosses among selected clones of 'Hunter River', 'UC110' and 'UC112' from the University of California, and lowland Turkish lines. Both 'Hely 8' and 'Hely 11' were sown in an irrigated trial at Yanco, NSW during 1979 and in one irrigated and one dryland trial near Tamworth, NSW during 1980. A second trial was sown at Yanco in 1982 using open-pollinated seed from the original 1979-sown trial. Selections from the Tamworth trials were crossed in the greenhouse during 1983 and the resulting populations screened intensively within and among half-sib families for resistance to colletotrichum crown rot (Colletotrichum trifolii) and spotted alfalfa aphid (Therioaphis trifolii f. maculata). 'Genesis' is the result of crossing these selections for pest resistance with field-adapted plants dug from the open-pollinated progenies in the 1982-sown trial at Yanco. 'Genesis' is a synthetic variety based on 185 plants in the final generation. Propagation is by seed.
Comparative Trial Comparators: 'Aquarius', 'CUF-101', 'Sceptre', 'Quadrella', 'Aurora'. Location: Yanco, NSW Dec 1993 to Apr 1995. Conditions: red-brown earth, irrigated, no obvious disease or nutrient disorders. Trial design: randomised complete block with four replicates, 30cm within and between row spacings, with separate row plots arranged in two replicates for flower colour measurements. Measurements: 80 plants per variety.
Prior Applications and Sales Nil.
Description: RW Williams, NSW Agriculture, Yanco, NSW.
Comparison of Medicago varieties
____________________________________________________________________________________ 'Genesis' 'Aquarius' *'CUF-101' *'Sceptre' *'Quadrella' *'Aurora'
____________________________________________________________________________________PLANT HEIGHT (cm) 7/10/94 (natural height at spring time) LSD(P0.01) = 2.6)
mean 29.0bc 28.8bc 33.3a 27.5c 30.5ab 28.1bc
std deviation 5.4 6.1 6.5 5.9 4.8 7.0
____________________________________________________________________________________PLANT HEIGHT (cm) 11/1/9 5 (height at flowering after 1st cut) LSD(P0.01) = 2.5)
mean 52.7a 56.7c 54.5 abc 53.5bc 53.2c 55.9ab
std deviation 4.9 6.0 7.4 4.8 6.5 6.1
____________________________________________________________________________________PLANT HEIGHT (cm) 2/3/95 (height at flowering after 3rd cut) LSD(P0.01) = 3.5)
mean 43.9c 48.4b 54.9 a 47.8b 48.1b 48.9b
std deviation 8.7 7.8 9.9 7.9 7.6 9.1
____________________________________________________________________________________PLANT HEIGHT (cm) 4/4/95 (4 wks regrowth, cut 2 wks after equinox in 2nd year) LSD(P0.01) = 2.7)
mean 29.4c 32.3b 37.5a 32.6b 32.8b 30.9bc
std deviation 6.3 6.5 6.5 6.5 6.3 7.5
____________________________________________________________________________________PLANT GROWTH HABIT
semi-erect medium erect erect semi-erect medium
____________________________________________________________________________________PLANT FOLIAGE GREEN COLOUR
dark medium light medium medium medium
____________________________________________________________________________________RESISTANCE TO PHYTOPHTHORA ROOT ROT (% seedling survivors) LSD(P0.01) = 18.6)
mean 61.2b 85.8a 64.6 b 49.1b 52.3b 65.9b
std deviation 6.2 9.3 15.9 15.6 15.2 5.1
____________________________________________________________________________________RESISTANCE TO SPOTTED ALFALFA APHID (% seedling survivors) LSD(P0.01) = 18.0)
mean 28.0c 34.2bc 48.8ab 40.5abc 23.5c 57.0a
std deviation 6.8 8.0 18.0 15.6 10.8 10.3
____________________________________________________________________________________Means followed by the same letter are not significantly different at P0.01.