Effects of Varied Nitrogen Levels and Plant Populations on yield Response

of NERICA 1 Variety

Presented at NIB forumBy

Oyange A. Wilson - RiceMAPPon 14.6.2013

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INTRODUCTION Trend of cultivation expansion is towards upland

ecosystem, where 80% of farmers earn their living

NERICAs have shown potential in both L/land & U/land ecosystems; yields & stress tolerance

For optimum yields, N application at appropriate spacing enhances morphological characteristics & optimizes yield

Many farmers still don’t consider planting density as an important factor in rice productivity

80% hence plant at random & apply less fertilizers

Work focused on response to N levels & spacings.2

Statement of the problem Rice production is low and production hardly

meets 50% of the demand There is a shift in consumption from maize to

rice with demand growing at 12% per annum 80% of rice grown in Lowland and 20% in

upland ecosystem. Land expansion static in irrigated areas

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Specific objectives

To determine the effect of different N application rates on grain yield of NERICA 1

The effect of different planting densities on growth and grain yield of NERICA1

Any interaction between density and N levels in relation to NERICA 1 grain yield and yield components

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MATERIALS AND METHOD

The experiment was done at MIAD center and KARI

Rainfall: bimodal, 930mm, and 510mm, 66% reliable

Temperature ave. 22oC, Min - 17 & max – 28 oC

Analysis done for soil, plant nutrients and weather data

taken for the period.

NERICA 1 variety was used at 3 Fertilizer levels of 0,

60 and 120kg ha-1 & 3 spacings of 30x15, 25x15 &

20x15 cm

The trial was a 3x3 factorial in split plot design with 3

replications, total 27 plots, each 3x3m

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Treatments and treatment combinations

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Where ; F1- 0kg N ha-1, F2-60kg N ha-1, F3- 120kg N ha-1:

S1- 30x15cm, S2- 25x15cm, S3- 20X15cm

Data collection Growth parameters; Plant height, Tillers, SPAD, Culm length,

Yield parameters: Panilces m-2, spikelets panicle-1, 1000 gwt, %filling, HI

P&D assessments

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Time line: 21, 30, 45, 55,75 & 110 DAT

Analysis: LSD used to separate means separated at 5% sig

Weather

R/f: 176mm

< 20mm/wk 8

0

5

10

15

20

25

30

35

40

45

50 Temp & Rainfall pattern

R/fMax temp Min TempAve temp

Dates

Soils Nutrient

Adapted from MIAD laboratory

N, < 0.25% recommended, supply41%, 35kg/ha rqt equivalent

P = 71 % of requirement, equivalent to 45kg/ha (P2O5) requirement

K20= 35% requirement, equivalent to 25kg/ha K2O

PH= 6.65 Max P avail.9

  N% P(ppm) K(meq%) PH  0.189 19.0 0.127 6.58

  0.109 21.0 0.170 6.71

Average 0.149 20 0.1485 6.65

1. Plant height

N on Plant ht spacing on Plant ht

N levels on plant height Spacing on plant height

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  0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1   -4.4204* - 6.1961*60 kg N ha-1 4.4204*   -1.7757*120 kg N ha-

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6.1961* 1.7757*  

  30 x 15 cm 25 x15 cm 20 x15 cm

30 x 15 cm   2.0124* 2.6089*

25 x 15 cm -2.0124*   .5966

20 x 15 cm -2.069* .5966  

Results

1. Tillers

Tillers Vs Spacing Tillers Vs N Levels N effect on tillers Spacing on tillers

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  0 kg N ha-1 60 kg ha-1 120 kg N ha-1

0 kg N ha-1   -26.02* - 58.91*60 kg N ha-1 26.02*   -32.89*120 kg N ha-1 58.91* 32.89*  

  30 x15 cm 25 x 15 cm 20 x 15 cm

30 x 15 cm   26.00 * -53.00*25 x 15 cm -26.00*   -79.00*20 x15 cm 53.00* 79.00*  

3. Panicle length

Effect of Nitrogen on P/length Effect of spacing on P/length

* There is an Interaction 12

  0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1   -1.8556* -3.1556*

60 kg N ha-1 1.8556*   -1.3000*

120 kg N ha-1 3.1556* 1.3000*  

  30 x15 cm 25 x 15 cm 20 x 15 cm

30 x15 cm   .3000 1.0556*

25 x 15 cm -.3000   .7556*

20 x15 cm -1.0556* -.7556*  

4. Culm length

Effect of N on culm lenth Effect of spacing on culm length

N on culm length

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0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1 -.2733* -.5256*

60 kg N ha-1 .2733* -.2522*

120 kg N ha-1 .5256* .2522*

5. Panicles m-2

N levels & Spacing on P m-2

N on p m-2 spacing on Pm-2

* There is an interaction

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  0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1   -191.67* -211.67*

60 kg N ha-1 191.67*   -20.00120 kg N ha-1 211.67* 20.00  

  30 x15 cm 25 x15 cm 20 x15 cm30 x15 cm   13.67 -13.67

25 x 15 cm -13.67   -27.33*

20 x15 cm 13.67 27.33*  

6. Spikelets panicle-1

N & Spacing on Spikelets/panicle

N on spikelets/panicle

15 0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1 -9.78 -24.11*

60 kg N ha-1 9.78 -14.33*

120 kg N ha-1 24.11* 14.33*

7. % filled grains

Effect of N & spacing on % filled grains

N on % filled grains spacing on % filled grains

*Interaction

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  0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1   .1841* .2524*

60 kg N ha-1 -.1841*   .0683*

120 kg N ha-1 -.2524* -.0683*  

  30 x15 cm 25 x15 cm 20 x 15 cm

30 x15 cm   .0231 .0497*

25 x 15 cm -.0231   .0265

20 x15 cm -.0497* -.0265  

7. Grain wt

N levels on grain wt

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  0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1   -.001044* .00013360 kg N ha-1 .001044*   .001178*

120 kg N ha-1 -.000133 -.001178*  

9. Yield

N & spacing on yield

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  0 kg N ha-1 60 kg N ha-1 120 kg N ha-1

0 kg N ha-1   -191.67* -211.67*

60 kg N ha-1 191.67*   -20.00120 kg N ha-1 211.67* 20.00  

Conclusion Nitrogen level of 60 kg N ha-1 at 20 x 15cm

spacing gives optimum yields hence better for NERICA 1 farmers

Harvesting at more than 110 DAT can possibly increase the % filling & grain yield at high N levels

Tillers per m2, spikelet per panicle and 1000 grain weight increased to optimum levels at 60 kg ha-1. A possibility of higher optimum levels should be tested at between 100-120 kg N ha-1.

Delayed effect of Nitrogen on maturity partly contributed to the reduction in percentage of filled grains with increased N levels.

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Polyethene sheathing on plots to prevent lateral seepage of nutrients ; 1.12.2012 followed by transplanting on 5.12.2012

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NERICA crop at

NERICA TRIAL SITE ON 6/2/2012: 60 DAT; Crop at Panicle initiation stage; less than 3% headed

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NERICA crop at 80DAT; heading; 23.2.2013

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NERICA crop at 80DAT; heading; 23.2.2013

SCHEDULE OF ACTIVITIESMonths Oct Nov Dec Jan Feb March

Week(s) 3 1 2 3 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4

Activities                                        

Nursery establishment                                        

Rice trial transplanting                                        

Weeding                                    

1st split application                                        

2nd split application                                        

Leaf area assessment                                        

SPAD assessment                                        

Plant lenght assessment                                  

Lodging Assessment                                      

Soil analysis                                      

Harvesting                                        

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