Transcription of Biotic Stress Associated Genes in White Clover (Trifolium repens L.) Differs in Response to Cyst and Root-Knot Nematode Infection

SummaryThe expression of symptoms of stem nematode reproduction on a total of 53 white clovers (26 cultivars, 14 genepools and 13 introductions from plant collections) was studied in a series of field and glasshouse experiments. Seedlings or stolon-tip cuttings were inoculated with nematodes and the clovers classified by the proportion of plants which developed symptoms. Significant differences were found between varieties although in each test the majority was intermediate between more resistant and susceptible extremes. There was significant positive correlation between tests, in spite of different inoculation methods and different average levels of susceptibility. Very large-leaved cv. Aran was more resistant than most other clovers tested, and small-leaved cv. S. 184 was more susceptible. There was no general correlation of leaf size with reaction to stemnematode. Small-leaved cv. Pronitro was also resistant while several large-leaved cultivars were susceptible. In observations of plants exposed to nematodes over a long period, either by sequential inoculations or through perpetuating latent infections, apparently resistant plants eventually succumbed and supported nematode reproduction. It has not been determined whether this was because selection for virulence in the nematodes had occurred.

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Third generation progress in breeding white clover for resistance to root-knot nematode

NZGA: Research and Practice Series ◽

10.33584/rps.6.1995.3360 ◽

1996 ◽

Vol 6 ◽

pp. 163-166

Author(s):

J. Van den Bosch ◽

C.F. Mercer

Keyword(s):

White Clover ◽

Trifolium Repens ◽

Egg Production ◽

Control Method ◽

Dry Weight ◽

Third Generation ◽

Root Knot Nematode ◽

Root Dry Weight ◽

Wide Range ◽

Meloidogyne Sp

Root-knot nematode (Meloidogyne sp.) reduces growth and nutrition of white clover (Trifolium repens L.) in New Zealand, and breeding resistant cultivars (with low galls per gram of root) is the preferred control method. Resistant and susceptible selections were bred from a wide range of white clover lines for three generations. In the third generation there were significant differences between seed lines from the selections for number of galls, root dry weight, visual growth score and galls/gram of root dry weight. Resistant selections had 43% of the susceptible selections' galls per gram, and 50% of the number of galls. Germplasm showing resistance to Meloidogyne spp. in the USA showed partial resistance to the local Meloidogyne sp. Two resistant and two susceptible genotypes were also compared for nematode egg production; resistant genotypes had a mean of 3,460 eggs/plant, compared to 25,030 for susceptible genotypes. Keywords: breeding, Meloidogyne sp., resistance, rootknot nematode, screening, selection, Trifolium repens, white clover

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Transcriptome analysis reveals potential genes involved in flower pigmentation in a red-flowered mutant of white clover (Trifolium repens L.)

Genomics ◽

10.1016/j.ygeno.2017.09.011 ◽

2018 ◽

Vol 110 (3) ◽

pp. 191-200 ◽

Cited By ~ 5

Author(s):

Heshan Zhang ◽

Hong Tian ◽

Mingxin Chen ◽

Junbo Xiong ◽

Hua Cai ◽

...

Keyword(s):

White Clover ◽

Transcriptome Analysis ◽

Trifolium Repens ◽

Trifolium Repens L ◽

Flower Pigmentation

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Impact of Environmental Factors on Seed Germination and Seedling Emergence of White Clover (Trifolium repens L.)

Agronomy ◽

10.3390/agronomy12010190 ◽

2022 ◽

Vol 12 (1) ◽

pp. 190

Author(s):

Lei Chu ◽

Yiping Gao ◽

Lingling Chen ◽

Patrick E. McCullough ◽

David Jespersen ◽

...

Keyword(s):

Seed Germination ◽

Environmental Factors ◽

White Clover ◽

Trifolium Repens ◽

Germination Rate ◽

Seedling Emergence ◽

Soil Surface ◽

High Sensitivity ◽

Series Of Experiments ◽

Trifolium Repens L

White clover (Trifolium repens L.) is cultivated as a forage crop and planted in various landscapes for soil conservation. There are numerous reports of failed white clover stands each year. A good understanding of the seed germination biology of white clover in relation to environmental factors is essential to achieve successful stand establishment. A series of experiments were conducted to investigate the impacts of light, temperature, planting depth, drought, and salt stress on seed germination and the emergence of white clover. White clover is negatively photoblastic, and seed germination averaged 63 and 66% under light and complete dark conditions 4 weeks after planting (WAP), respectively. Temperature affected the seed germination speed and rate. At 1 WAP, seeds incubated at 15 to 25 °C demonstrated a significantly higher germination rate than the low temperatures at 5 and 10 °C; however, the germination rate did not differ among the temperature treatments at 4 WAP. The results suggest that white clover germination decreases with increasing sowing depths, and the seeds should be sown on the soil surface or shallowly buried at a depth ≤1 cm to achieve an optimal emergence. White clover seeds exhibited high sensitivity to drought and salinity stress. The osmotic potential and NaCl concentration required to inhibit 50% seed germination were −0.19 MPa and 62.4 mM, respectively. Overall, these findings provide quantifiable explanations for inconsistent establishment observed in field conditions. The results obtained in this research can be used to develop effective planting strategies and support the successful establishment of white clover stands.

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Enhanced drought tolerance in white clover

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1993.55.2090 ◽

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

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Influence of boron on the reproductive growth of white clover (Trifolium repens L.) cultivars

Annals of Applied Biology ◽

10.1111/j.1744-7348.1991.tb04893.x ◽

1991 ◽

Vol 119 (3) ◽

pp. 541-548 ◽

Cited By ~ 3

Author(s):

A. H. MARSHALL ◽

H. K. KHRBEET ◽

D. H. HIDES

Keyword(s):

White Clover ◽

Trifolium Repens ◽

Reproductive Growth ◽

Trifolium Repens L

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