Genotypic variation and covariation in wheat seedling seminal root architecture and grain yield under field conditions.

Autor: Rebetzke GJ; CSIRO Agriculture and Food, PO Box 1700, Canberra, ACT, 2601, Australia. Greg.Rebetzke@csiro.au., Zhang H; State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China., Ingvordsen CH; Australian Grain Technologies, PO Box 341, Roseworthy, SA, 5371, Australia., Condon AG; CSIRO Agriculture and Food, PO Box 1700, Canberra, ACT, 2601, Australia., Rich SM; CSIRO Agriculture and Food, 147 Underwood Av, Floreat, WA, 6014, Australia., Ellis MH; Formerly CSIRO, Now 8 Avenue Piaton, Villeurbanne, France.
Jazyk: angličtina
Zdroj: TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik [Theor Appl Genet] 2022 Sep; Vol. 135 (9), pp. 3247-3264. Date of Electronic Publication: 2022 Aug 04.
DOI: 10.1007/s00122-022-04183-z
Abstrakt: Key Message: Greater embryo size in a large and carefully phenotyped mapping population was genetically associated with a greater number of longer seminal roots to increase grain yield in droughted field environments. Breeding modification of root architecture is challenging in field environments owing to genetic and phenotypic complexity, and poor repeatability with root sampling. Seeds from a large mapping population varying in embryo size were harvested from a common glasshouse and standardised to a common size before assessing in rolled germination paper at 12 and 20 °C for seedling growth. Differences in genotype means were large and heritabilities high (h 2 = 0.55-0.93) indicating strong and repeatable genotypic differences for most root traits. Seminal roots 1 to 3 were produced on all seedlings, whereas growth of seminal roots 4, 5 and 6 was associated with differences in embryo size. Increases in seminal root number from 4 to 6 per plant were strongly, genetically correlated with increases in total seminal length (r g = 0.84, < 0.01). Multivariate analysis confirmed initiation and growth of seminal roots 1, 2 and 3, and of roots 4, 5 and 6 behaved as genetically independent (r Pg = 0.15 ns) cohorts. Tails representing extremes in seedling root length and number were associated with significant differences in grain yield of up to 35% in droughted field environments but were not different in irrigated environments. Increases in grain yield were linked to greater lengths of seminal roots 4, 5 and 6 and were largely independent of plant height or development. This is the first report on the genetic relationship of seedling root architecture and embryo size, and potential in selection of seminal root size for accessing deep-soil moisture in droughted environments.
(© 2022. Crown.)
Databáze: MEDLINE
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