Inheritance of phosphorus response in white clover (Trifolium repens L.)

Self Cite

White clover breeding lines developed as high and low P-responsive, in glasshouse selection trials, were compared, over three years, with 17 other breeding lines and cultivars for growth in four soil-fertility treatments under two defoliation treatments on a hill-country farm. Differences between P-response groups were transitory and biologically insignificant. Selection for differences in response to P in a controlled environment was not successful in identifying white clover germplasm adapted to low P hill-country soils. White clover breeding lines and cultivars that achieved high growth over the 3-year duration of the trial had New Zealand parentage and were all medium to small leaf types.

Section: A99008mentioning

confidence: 99%

Section: A99008mentioning

confidence: 99%

Adaptation to low fertility hill country in New Zealand of white clover lines selected for differences in response to phosphorus

Caradus

Dunn

2000

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“…The primary selection force acting on the various populations within the field experiment is assumed to be variable soil-P availability. There is heritable variation within white clover for P response characteristics (Caradus et al 1992), satisfying one of the key conditions that must be met for differentiation to occur (Endler 1986). The specific aim of the research was to establish whether or not genetic differentiation had occurred in the sown populations.…”

Section: Introductionmentioning

confidence: 99%

Genetic differentiation in white clover(Trifolium repens)populations during 8 years of contrasting phosphorus supply in New Zealand hill country

Wedderburn

Barker

Chapman

et al. 2005

Genetic differentiation under the selection force of variable soil P availability was measured in populations of two white clover cultivars introduced to a grazed, low fertility grassland site. The resulting mixed grass-clover pastures subsequently received contrasting levels of phosphorus (P) fertiliser for 8 years. Afield-based reciprocal transplant experiment and two controlled-environment experiments were conducted using plants removed from the 8-year field experiment and appropriate controls to test the hypotheses that: (1) genetic differentiation occurred within the white clover populations in response to variation in P supply; and (2) surviving plants which demonstrated genetic differentiation under high-P conditions would continue to do this when grown in mixtures with plant material removed from unsown pasture.

“…The method of identification of intraspecific variation for P response in white clover has been documented elsewhere (Caradus et al 1992(Caradus et al , 1993. Genotypes used in this study to examine if yield differences as a result of P supply were associated with variation in shoot %P and %N, came from an evaluation in which 110 white clover genotypes (10 genotypes from 11 cultivars) were grown in pots in a glasshouse for 6 weeks at seven P levels with three replicates.…”

Section: Methodsmentioning

confidence: 99%

“…Identification of high and low phosphorusresponding genotypes (Caradus et al 1992). Principal component 1 was predominantly an indicator of plant size (Table 1).…”

Section: Methodsmentioning

confidence: 99%

Nitrogen and phosphorus concentrations of white clover genotypes differing in response to added phosphorus

Caradus¹,

Dunlop²,

Wewala³

et al. 1993

Self Cite

The phosphorus (P) response of 110 white clover (Trifolium repens L.) genotypes was determined in a glasshouse pot 'experiment. The nitrogen (N) and P contents of leaf, stolon, and flower components were determined for the seven most responsive and seven least responsive genotypes. The most P-responsive genotypes had lower % N and % P levels, lower NIP ratios, but higher total N and P contents compared with the least Presponsive genotypes. While the present study showed that selection for variation in P response may result in associated differences in % P content, the converse was not true. Leaf %N and NIP ratio, which provide an indication of the plant's ability to utilise P for N fixation and N assimilation into dry matter, provided a better explanation of differences in P response than leaf %P alone. Broad-sense heritabilities for %P, %N, and NIP ratio in leaf tissue were 0.52,0.65, and 0.66, respectively, determined over all 110 genotypes at a P level giving 80-90% maximum yield.