scholarly journals Enhanced drought tolerance in white clover

1993 ◽  
pp. 97-100
Author(s):  
J. Van den Bosch ◽  
I.K. Black ◽  
G.R. Cousins ◽  
D.R. Woodfield
Keyword(s):  
New Zealand ◽  
Drought Tolerance ◽  
White Clover ◽  
Trifolium Repens ◽  
Root Morphology ◽  
Forage Yield ◽  
Plant Survival ◽  
Breeding Programmes ◽  
Trifolium Repens L ◽  
Per Se

Drought-stress limits white clover (Trifolium repens L.) persistence in many New Zealand regions. As a component of breeding for enhanced drought tolerance, 8 selection groups (110 lines in total) of white clover were evaluated in the Wairarapa over a 2-year period. The selection groups included Australian white clover ecotypes, selections from New Zealand dryland populations, root morphology selections, pre-release selections from New Zealand breeding programmes, and existing overseas and New Zealand cultivars. The selection groups derived from New Zealand dryland populations had the highest forage yield and plant survival, 21 of the 24 individual lines with >30% plant survival coming from these groups. Groups containing Australian ecotypes and overseas cultivars had the lowest forage yield and plant survival. Selections for root morphology per se were lower yielding and less persistent than selections made from New Zealand dryland populations evaluated in drought-prone environments. However, some improvements in forage yield and persistence were observed through selecting for root morphology after screening the same New Zealand dryland populations in a drought-prone North Canterbury site. Keywords: drought tolerance, plant breeding, root morphology, Trifolium repens

BREEDING A WHITE CLOVER ADAPTED TO SOUTHERN LOWLAND REGIONS OF NEW ZEALAND

1985 ◽  
pp. 203-207
Author(s):  
K.H. Widdup
Keyword(s):  
New Zealand ◽  
White Clover ◽  
Trifolium Repens ◽  
Growth Habit ◽  
Agronomic Performance ◽  
Sheep Grazing ◽  
Growth Morphology ◽  
Active Growth ◽  
Hill Country ◽  
Trifolium Repens L

White clover populations from Europe and New Zealand together with ecotypes collected from old pastures in Southland-Otago were evaluated as spaced plants at Gore. Plants were screened for herbage production and morphological and flowering characteristics. The Southland ecotypes and North Island hill country material are adapted to active growth in spring and summer. Their dense growth habit ensures continued production of branched stolons from nodal meristems which is necessary for high clover yield and persistence under intensive sheep grazing. In this region flowering characteristics are unimportant in relation to agronomic performance. Some largerleaved Huia and French lines have high-yielding features which are evident during autumn under lenient grazing. Hybrids between superior plants showing adaptive and high yie!ding features are being screened in order to select new types with the desired characteristics. Keywords: White clover, Trifolium repens L., plant breeding, southern region, ecotypes, growth, morphology.

Genotypic evaluation of introduced white clover (Trifolium repens L.) germplasm in New Zealand

2016 ◽  
Vol 67 (8) ◽  
pp. 897 ◽  
Author(s):  
M. Z. Z. Jahufer ◽  
J. L. Ford ◽  
D. R. W. Woodfield ◽  
B. A. Barrett
Keyword(s):  
New Zealand ◽  
White Clover ◽  
Trifolium Repens ◽  
Dry Matter ◽  
Allelic Variation ◽  
Genotypic Variation ◽  
Dry Matter Yield ◽  
Breeding Lines ◽  
F1 Progeny ◽  
Trifolium Repens L

Optimal evaluation and use of introduced germplasm for species improvement is an ongoing challenge. Research was conducted to survey a select set of introduced white clover (Trifolium repens L.) germplasm from broad geographic origins to assess their genetic potential, based on F1 crosses to elite New Zealand cultivars. The bulk progeny generated from test crosses to Grasslands cultivars Demand, Sustain and Kopu II were evaluated at Palmerston North under rotational grazing by sheep. The replicated trial consisted of the 26 germplasm accessions, three cultivars used as maternal parents, and 78 F1 bulk progeny breeding lines. Three morphological traits and estimated seasonal dry matter yield were measured over four years. Significant (P < 0.05) genotypic variation was observed for all these traits among the parents and F1 progeny lines. F1 progeny lines with traits values greater than the cultivars were identified. Significant (P < 0.05) genotype-by-season (σ2gs) and genotype-by-year (σ2gy) interactions were estimated for dry matter yield. Principle component analysis of the F1 progeny-by-trait BLUP matrix identified 16 elite progeny lines with mean seasonal dry matter yield equal to or higher than the cultivars. Half of the lines had Demand as the cultivar parent, while only three had Kopu II as a parent. Fourteen of these progeny lines were derived from crosses to Australasian adapted germplasm. This study indicated that choice of adapted cultivar with which to cross is important, and introduced germplasm from Australasia is a valuable source of adaptive variation in these F1 progeny. More complex approaches may be needed to identify and use adaptive allelic variation from germplasm sources beyond Australasia.

scholarly journals Trends in the global marketing of white clover cultivars

1996 ◽  
Vol 6 ◽  
pp. 7-14
Author(s):  
R.D.J. Mather ◽  
D.T. Melhuish ◽  
M. Herlihy
Keyword(s):  
New Zealand ◽  
South America ◽  
White Clover ◽  
Trifolium Repens ◽  
Western Europe ◽  
Leaf Size ◽  
Global Market ◽  
Production Region ◽  
Trifolium Repens L ◽  
Clover Seed

White clover (Trifolium repens L.) is the dominant legume of temperate pastures, having been improved by breeding since the 1930s. The 1994 OECD Register lists 93 cultivars, with a further 25-30 cultivars also known to commerce. Therefore, in excess of 100 cultivars are available to fulfil a world annual market of 8500-10,500 MT. Globally, New Zealand is the major white clover production region, providing 50- 55% of the seed. Other key production regions are Denmark, USA and South America. Consumption of white clover has been relatively static for some time, ranging from 8000-10,000 MT per annum. Between 55-60% of the seed is used in the northern hemisphere (approx. 40% by Western Europe - UK, France, Germany). USA, South America and New Zealand all consume similar tonnages annually (approx. 1000-2000 MT each) with smaller tonnages used in Australia. One cultivar, Grasslands Huia, has dominated the world white clover seed market for many years and it still remains the world's major cultivar by volume. However, in the last 10 years its position has come under increasing pressure from New Zealand and international proprietary cultivars. Eventually proprietary cultivars with improved agronomic performance will supersede the consumption of commodity/public white clovers in those countries where national listing is required to obtain release and recommended listing is need to ensure successful marketing. Despite this, Grasslands Huia will continue for many years to play a major role in supplying markets where national listing is not a prerequisite to release and price is a major factor in purchase decisions. Keywords: commodity cultivar, global market, Grasslands Huia, leaf size, market share, production trends, proprietary cultivar, seed industry, Trifolium repens L., white clover

scholarly journals Factors affecting white clover persistence in New Zealand pastures

1996 ◽  
pp. 229-235 ◽  
Author(s):  
D.R. Woodfield ◽  
J.R. Caradus
Keyword(s):  
New Zealand ◽  
Plant Breeding ◽  
White Clover ◽  
Trifolium Repens ◽  
Plant Nutrition ◽  
Grazing Management ◽  
Yield Potential ◽  
Trifolium Repens L ◽  
Grass Growth ◽  
The Impact

Better persistence and reliability of white clover (Trifolium repens L.) is critical in achieving a more competitive New Zealand farming industry. To persist, white clover must establish well and withstand the accumulated stresses of competition from associated grasses, grazing, variable soil fertility, drought, plus pest and disease pressure. These factors vary markedly with environment and farming system, making the choice of appropriate grazing management, plant nutrition, companion species and cultivar difficult. White clover is particularly vulnerable to mismanagement and environmental stresses during spring when plant size is at its smallest. This vulnerability is further compounded by the current trend in dairying to apply high rates of nitrogen (N) which favours grass growth more than clover growth. A faster grazing rotation and/or higher stocking rates can offset the adverse effects of N on white clover by utilising the additional grass produced and reducing competition for light. Irrespective of N inputs, frequent defoliation during spring favours white clover persistence by increasing grass tiller density, resulting in better ground cover and in lower soil surface temperatures in summer. There is a threshold above which the density of associated grass suppresses clover growth. This is most prevalent in swards containing browntop, cocksfoot and kikuyu, which are more competitive against white clover than tall fescue, timothy and perennial ryegrass. Plant breeding efforts to improve persistence concentrate on increasing the rate of stolon formation and decreasing the rate of stolon death. These efforts include selecting genotypes that have better spread and persistence in association with different grasses, and genotypes that continue to grow with lower inputs of phosphate. Changes in root morphology have enhanced persistence under moderate drought stress, while significant improvements in resistance to clover cyst nematode, root-knot nematode and clover flea offer real hope in reducing the impact of these pests. Developing cultivars with higher stolon growing point densities at a particular leaf size should improve persistence while maintaining the greater yield potential. Keywords: climatic stresses, competition, diseases, grazing management, pests, plant breeding, plant nutrition, Trifolium repens L.

Grasslands Legacy - a new, large-leaved white clover cultivar with broad adaption

2015 ◽  
Vol 77 ◽  
pp. 211-218 ◽  
Author(s):  
J.L. Ford ◽  
G.R. Cousins ◽  
Z. Jahufer ◽  
I.J. Baird ◽  
D.R. Woodfield ◽  
...  
Keyword(s):  
New Zealand ◽  
White Clover ◽  
Trifolium Repens ◽  
Farming Practices ◽  
Early Generation ◽  
Nitrogen Fertiliser ◽  
Evaluation Systems ◽  
Breeding Objective ◽  
Trifolium Repens L ◽  
Stocking Rates

White clover (Trifolium repens L.) continues to play a pivotal role in the Australasian pastoral industry, despite increased use of nitrogen fertiliser on farms. Improved white clovers for dairy farming must be well adapted to the farm systems they are intended for, including increased rates of fertiliser nitrogen, higher stocking rates and access to irrigation. The breeding objective was to develop a white clover cultivar in evaluation systems that simulate modern farming practices, and test that cultivar in both New Zealand and Australia for adaptation and agronomic merit. This included breeding and early generation evaluation at research farms in the Manawatu and Waikato, with subsequent evaluations in these locations and farms in Southland and Victoria, Australia. This resulted in 'Grasslands Legacy', a new large leaved white clover cultivar bred for New Zealand and eastern temperate Australian pastures, which has shown significant (P

scholarly journals Development of white clover (Trifolium repens L.) cultivar Grasslands Challenge (G23)

1997 ◽  
pp. 99-102
Author(s):  
B.M. Cooper ◽  
P.T.P. Clifford ◽  
W.M. Williams
Keyword(s):  
New Zealand ◽  
White Clover ◽  
Trifolium Repens ◽  
Leaf Size ◽  
Grazing Pressure ◽  
Progeny Testing ◽  
Potential Growth ◽  
Leaf Disease ◽  
Early Results ◽  
Trifolium Repens L

Grasslands Challenge (Trifolium repens L.) white clover was developed to incorporate potential growth benefits, and disease resistance, in two double cross hybrids (Mediterranean × New Zealand) identified in evaluations at Kaikohe. Thirty-three elite selections of hybrids and New Zealand material were polycrossed for seed production. Progeny testing resulted in 27 parental lines with improved resistance to leaf disease and stem nematode (Ditylenchus dipsaci) relative to Grasslands Pitau. Testing of the maternal lines for seedling characteristics resulted in the deletion of one parent. A bulk line was evaluated in mini plots, and a hill country grazing trial, and showed improved growth to the control. In a grazing trial conducted in the Manawatu, Challenge showed outstanding winter production. The selection has a high stolon density in combination with a medium to large leaf size. This will allow Challenge to recover quicker from drought stress and grazing pressure. The plant type and early results indicate Challenge will be best suited to a rotational grazing management, particularly in regions where significant cool-season growth occurs. Plant Variety Rights were granted in 1997, and commercial seed should be available in 1998. Keywords: Grasslands Challenge, leaf disease, Mediterranean hybrids, stem nematode, Trifolium repens

Introgression as a Route to Improved Drought Tolerance in White Clover (Trifolium repens L.)

2001 ◽  
Vol 187 (1) ◽  
pp. 11-18 ◽  
Author(s):  
A. H. Marshall ◽  
C. Rascle ◽  
M. T. Abberton ◽  
T. P. T. Michaelson-Yeates ◽  
I. Rhodes
Keyword(s):  
Drought Tolerance ◽  
White Clover ◽  
Trifolium Repens ◽  
Trifolium Repens L
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