Leaf number on the maintiller

(1)

Achieving higher grain yield

through integrated crop

establishment

in irrigated rice fields

Tanguy Lafarge, Estela Pasuquin

Zuziana Susanti, Brenda Tubana, Crisanta Bueno

IRRC, 10 October 2006, New Delhi

(2)

• Addressing the impact of a single factor

by avoiding combining effects of

confounding factors

–

Changing one factor (seed density in the

nursery, transplanting age, nursery type)

independently of the others

–

Growing crops under the same climate

conditions

–

Transplanting plant at the same plant spacing

and density

–

Applying optimal nitrogen requirement (SPAD)

(3)

• Transplanting 20 to 30 days-old

seedlings (7 to 10-leaf stage)

–

Farmers prefer to transplant old seedlings

–

High tiller mortality if early transplanting may

induce significant dry matter loss

• Sowing in the nursery from 3000 to

10000 seeds m

-2

(75 to 250 g seeds m

-2

)

(4)

500 pl m

-2

3000 pl m

-2

40000 pl m

-2

10000 pl m

-2

IR72 in the nursery, 6 days after sowing

(5)

Days after sowing (days)

0 20 40 60 80

Leaf number on the maintiller

0 4 8 12 16 500 pl m-2 3000 pl m-2 10000 pl m-2 40000 pl m-2

Transplanting 35 days after sowing

Plant response to seed density

leaf 3

leaf 4

(6)

Days after sowing (days)

0 20 40 60 80

Leaf number on the maintiller

0 4 8 12 16 500 pl m-2 3000 pl m-2 10000 pl m-2 40000 pl m-2

Transplanting 35 days after sowing

main field

nursery

Leaf emergence was similar before and after transplanting whatever the seed density

Plant response to seed density

High seed density in the nursery affected leaf emergence No transplanting shock was observed on leaf emergence

-

variety IR72

- same sowing date and plant density after transplanting

Leaf emergence was affected in the nursery if high density

(7)

Days after sowing (days)

0 30 60 90 120 150

Productive tiller number per plant 0

5 10 15 20 500 pl m-2 3000 pl m-2 10000 pl m-2 40000 pl m-2

Transplanting 35 days after sowing

main field

nursery

Plant response to seed density

-Tiller emergence resumed right after transplanting whatever the density

I1

- Tiller emergence was delayed as soon as 14 DAS if density as high as 3000 seeds m-2 _{in the}

nursery

High seed density in the nursery affected tiller emergence Transplanting allowed tiller emergence to resume

-

variety IR72

(8)

- Tiller emergence was delayed if extended stay in the nursery

Plant response to transplanting age

P ro d uc ti ve till er num b er per plant 0 5 10 15 20 25 7 DAS 21 DAS 35 DAS

Days after sowing

0 40 80 120 Sh oo t d ry we ig ht (g plt -1 ) 0 10 20 30

Transplanting age: 7, 21 and 35 days (3, 7 and 11 leaf stage)

Nursery density: 3000 seeds m-2

Growth and development resumed right after transplanting

- Shoot dry weight was delayed if extended stay in the nursery and resumed thereafter

-

variety IR72

- Tiller emergence resumed right after transplanting

(9)

• Low seed rate in the nursery and early

transplanting did not delay leaf and tiller

emergence and shoot dry weight increase

• No transplanting shock was observed

–

Recovery in tiller emergence was observed right

after transplanting, whatever the seed density and

transplanting age were

–

Leaf emergence was not affected by transplanting

• Is there any positive effect on grain yield?

(10)

P ro d uc ti ve till er num b er per plant 0 5 10 15 20 25 7 DAS 21 DAS 35 DAS

Days after sowing

0 40 80 120 Sh oo t d ry we ig ht (g plt -1 ) 0 10 20 30

Transplanting age: 7, 21 and 35 days

(3, 7 and 11 leaf stage)

Nursery density: 3000 seeds m-2_{, hill spacing 20 x 20 cm}

Grain Yield (t ha-1₎

Mean S.E

7 DAS 4.06 0.02

21 DAS 3.98 0.38

35 DAS 3.11 0.31

IRRI, late wet season

- same climate conditions

- same plant density

- optimal nitrogen management

Yield increase with early transplanting

(11)

Productive tiller numbe r pe r plant 0 5 10 15 20 25 7 DAS 21 DAS 35 DAS

Days after sowing

0 40 80 120 S h oot dr y weight (g plt -1 ) 0 10 20 30

(3, 7 and 11 leaf stage)

Nursery density: 10000 seeds m-2 _{, hill spacing 20 x 20 cm}

Grain Yield (t ha-1₎

Mean S.E

7 DAS 4.40 0.12

21 DAS 3.86 0.30

35 DAS 2.95 0.29

IRRI, late wet season

- same plant density after transplanting

IR72

(12)

transplanted 7 days after sowing transplanted 21 days after sowing transplanted 14 days after sowing

IR72 in the main field,

34 days after sowing

for all 3 situations

Transplanting, hill spacing 20 x 20 cm

(13)

Grain Yield (t ha-1₎ Mean S.E 7 days transplanting 6.99 0.12 14 days transplanting 6.34 0.08 21 days transplanting 6.06 0.11

Productive tiller number

per plant 0 10 20 30 40 7 DAS 14 DAS 21 DAS

Days after sowing

0 40 80 120

Shoot dry weight

(g plt -1 ) 0 20 40 60

IRRI, dry season

IR72

(3, 5 and 7 leaf stage)

(14)

Grain Yield (t ha-1₎ Mean S.E 7 days transplanting 7.75 0.05 14 days transplanting 6.98 0.06 21 days transplanting 6.97 0.03

per plant 0 10 20 30 40 7 DAS 14 DAS 21 DAS

Days after sowing

0 40 80 120

Shoot dry weight

(g plt -1 ) 0 30 60

Hybrid rice

(3, 5 and 7 leaf stage)

IRRI, dry season

(15)

Grain yield (t ha-1₎

Dry season IR72 Hybrid1 Hybrid2

Mean S.E Mean S.E Mean S.E

7 DAT 6.99 0.12 7.75 0.05 7.58 0.02

14 DAT 6.34 0.08 6.98 0.06 6.81 0.07

21 DAT 6.06 0.11 6.97 0.03 6.99 0.05

Wet season IR72 Hybrid1 NPT

7 DAT 5.28 0.05 6.58 0.11 4.55 0.13

14 DAT 5.10 0.03 5.98 0.07 4.61 0.04

21 DAT 5.14 0.05 5.86 0.03 2.59 0.25

(3, 5 and 7 leaf stage)

Response valid for a range of genotypes and seasons

(16)

Tiller mortality rate

Dry season IR72 Hybrid 1 Hybrid 2

7 DAT 0.43 0.04 0.39 0.04 0.32 0.03

14 DAT 0.31 0.04 0.26 0.02 0.19 0.03

21 DAT 0.25 0.02 0.23 0.02 0.34 0.04

Wet season IR72 Hybrid 1 NPT

7 DAT 0.51 0.03 0.43 0.04 0.46 0.02

14 DAT 0.50 0.03 0.35 0.04 0.39 0.04

21 DAT 0.44 0.03 0.27 0.05 0.31 0.08

(3, 5 and 7 leaf stage)

Response associated with higher tiller mortality rate

(17)

Wet-bed

Mat nursery

Seedling tray

Dapog

(18)

Grain Yield (t ha-1₎ Mean S.E ST14 7.59 0.03 WB14 6.98 0.06 MN14 7.69 0.04 DP14 7.03 0.04

per plant 0 10 20 30 ST WB MN DP

Days after sowing

0 40 80 120

Shoot dry weight

(g plt -1 ) 0 30 60

Hybrid rice

Plant response to nursery type

IRRI, dry season

- same plant density in nursery and field

- same transplanting age

(19)

Grain yield (t ha-1₎

Dry season IR72 Hybrid 1 Hybrid 2

ST14 6.55 0.03 7.59 0.03 6.98 0.01

WB14 6.34 0.08 6.98 0.06 6.81 0.07

MN14 6.54 0.04 7.69 0.04 6.91 0.04

DP14 6.39 0.18 7.03 0.04 6.78 0.04

Wet season IR72 Hybrid 1 NPT

ST14 5.26 0.11 6.29 0.03 4.45 0.07

WB14 5.10 0.03 5.98 0.07 4.61 0.04

MN14 5.02 0.08 6.08 0.02 4.90 0.07

(20)

• Early transplanting induced a significant

increase in grain yield (up to 1 t ha

-1

_{in some}

conditions)

–

due to earlier tiller and leaf area production

–

valid for contrasted genotypes and growing conditions

• Early transplanting shall promote a significant

reduction in nursery area

–

as long as the seed rate in the nursery is increased

(21)

• One specific nursery type might be

genotype specific and did not have a

significant impact on grain yield

–

as long as the different types were compared

with the same transplanting age, same seed

rate in the nursery and same climate conditions

• Higher grain yield was associated with a

higher tiller mortality rate (in response to

early transplanting)

(22)

(23)

H1 H3 I1 N1

Method mean se mean se mean se mean se

Transplanting 9.02 0.45 8.28 0.16 6.06 0.10 8.01 0.34

Broadcasting 7.63 0.41 9.24 0.29 6.72 0.26 7.15 0.53

Row seeding 7.71 0.22 8.44 0.30 6.71 0.20 7.62 0.24

Hill sowing 8.25 0.20 8.18 0.42 6.70 0.11 7.32 0.19

Comparison of grain yield between

transplanting and direct-seeding

(24)

H1 H3 I1 N1

Method mean se mean se mean se mean se

Transplanting 0.59 0.02 0.63 0.01 0.68 0.02 0.62 0.02

Broadcasting 0.69 0.02 0.69 0.04 0.77 0.02 0.71 0.02

Row seeding 0.68 0.05 0.65 0.03 0.75 0.03 0.69 0.01

Hill sowing 0.68 0.01 0.70 0.03 0.73 0.03 0.64 0.00