SEED SET EVALUATION IN INTER-SPECIFIC HYBRIDS OF LOTUS

R. Reyno, D. Steinhorst and M. RebuffoIFTBC 2019, Orlando, FL

25 March, 2019

Agronomic traits of Birdsfoot trefoil

Lotus corniculatus INIA Draco Erect habit Drought tolerant Adapted to wide range of soils (not wet) High seed potential Low level of condensed tannins Highly used in Uruguay

Agronomic traits of the Greater Lotus

Lotus uliginosus INIA Gemma Prostrate habit Persistent Highly rhizomatous Well adapted to wet soils No drought tolerance Low seed production Medium-high levels of condensed tannins

What do we want with the hybrids?

Semi-erect habit Persistent Rhizomes Wide adaptation Drought tolerant High seed production Intermediate levels of

condensed tannins

Greater Lotus INIA Gemma

44 F1 Hybrids

Birdsfoot trefoilINIA Draco

24 F1 Hybrids

Reciprocal crosses

F1 hybrid plantF1 hybrid plant

Hybrid verification by DNA content

Greater Lotus (L. uliginosus) Birdsfoot trefoil (L. corniculatus)

Hybrids (L. uliginosus x L. corniculatus)

Hybrids (L. corniculatus x L. uliginosus)

Castillo et al., 2012. Crop Science 52 (4): 1572-1582

Low seed set in the F1 plants

Half-sib family evaluation: first cycle of selection

Polycross of the 44 F1 plants (Lu x Lc)

Polycross of the 24 F1 plants (Lc x Lu)

Evaluation of 40 plants from each half-sib family

2 sites

2720 plants

Seed set evaluation of the half-sib families

Flowers head-1 Pods head-1 Seed (gr) plant-1

Average Range Average Range Average Range

INIA Draco 5.38 4.0-7.5 3.92 2.2-7.6 5.91 0.04-34.12

H-Lc (24 HSF) 5.78 3.0-8.5 3.64 1.5-9.2 4.60 0.03-25.75

H-Lu (44 HSF) 6.51 2.5-10.5 5.36 2.9-9.0 5.20 0.01-45.79

INIA Gemma 7.67 5.5-11 6.09 2.6-9.0 1.86 0.06-10.15

Rebuffo and Reyno, unpublished data

Among and within family selection

50 plants (Lu x Lc) selected for high seed set

25 plants (Lu x Lc) selected for low seed set

36 plants (Lc x Lu) selected for high seed set

25 plants (Lc x Lu) selected for low seed set

2 sites

Lines Number of Pods head-1 Seed grams (20 head) TSW (gr)

INIA Draco 4,6 d 1,63 a 1,4 a

H-Lc (high seed set) 5,0 b 1,35 ab 1,4 a

H-Lc (low seed set) 4,3 cd 0,96 c 1,5 a

INIA Gemma 8,1 a 1,09 bc 0,7 b

H-Lu (high seed set) 5,6 b 0,88 cd 0,9 b

H-Lu (low seed set) 5,4 bc 0,55 d 0,9 b

Seed set evaluation in experimental lines

Lines Number of Pods head-1 Seed grams (20 head) TSW (gr)

INIA Draco 4,6 d 1,63 a 1,4 a

H-Lc (high seed set) 5,0 b 1,35 ab 1,4 a

H-Lc (low seed set) 4,3 cd 0,96 c 1,5 a

INIA Gemma 8,1 a 1,09 bc 0,7 b

H-Lu (high seed set) 5,6 b 0,88 cd 0,9 b

H-Lu (low seed set) 5,4 bc 0,55 d 0,9 b

Seed set evaluation in experimental lines

Maternal effect

Seed set evaluation in experimental linesSeed Production (kg ha-1)

Glencoe La Estanzuela Overall average

INIA Draco 234 a 84 a 170 a

H-Lc (high seed set) 211 a 61 a 136 b

H-Lc (low seed set) 90 b 39 abc 61 c

INIA Gemma 51 ab 51 c

H-Lu (high seed set) 73 bc 18 bc 45 c

H-Lu (low seed set) 22 c 4 c 13 d

Seed set evaluation in experimental linesSeed Production (kg ha-1)

Glencoe La Estanzuela Overall average

INIA Draco 234 a 84 a 170 a

H-Lc (high seed set) 211 a 61 a 136 b

H-Lc (low seed set) 90 b 39 abc 61 c

INIA Gemma 51 ab 51 c

H-Lu (high seed set) 73 bc 18 bc 45 c

H-Lu (low seed set) 22 c 4 c 13 d

H-Lu hybrid groups represent only 30% of seed production than de H-Lcgroups.

INIA Gemma also represents only 30% of the INIA Draco´s seed production

Maternal effect

Plant with rhizomes

Plant diameter

Rhizobiology

Seed production (gr in 5 heads) of the 50 HSF from the H-Lu

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.4543 G4 19 12

Gem

ma 16 46 40 15 42 23 35 47 36 49 31 32 27 17 G5 38 9 10 G6 26 41 20 48

San

Gabr

iel

39 18 6 7 14Ri

gel 2 11 33 3 34 50 28 30 4

Drac

o 5 21 8 22 13 24 1 25E-

Tani

n 45 37

Greater Lotus (L. uliginosus)Birdsfoot trefoil (L. corniculatus)

Parents average = 0,24 Families average = 0,27 Several families above the superior parent

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.5043 35 39 12 48 42 17 26 40 9 10 G4 32 36 19 49 46 33 16 2 50 23 15 8 18 47 20 24

Gem

ma 31 28 38 3 37 41

E-Ta

nin 11 30 25 6 27 34 5 21 22 7 14 4 45 1 G6 13 G5

San

Gabr

iel

Drac

oRi

gel

Greater Lotus (L. uliginosus)

Birdsfoot trefoil (L. corniculatus)

Parents average = 1,73 Families average = 0,77 No families above the superior parent Within the best families there are individual

plants as good as the superior parent

Seed production (gr plant-1) of the 50 HSF from the H-Lu

So far we found…. Maternal effect Foliage size Habit Fertility (seed/head) Agronomic traits

Average family from Lu x Lc produces less seed than average family from Lc x Lu

Highly variable among and within half-sib families

Keep working on…

Seed production High fertility (seed/head) High seed production (heads/m2)

Dry matter production Rhizomes Condensed tannin expression Rhizobiology

Backcrossing

Thank you