Contribution of leaves to the yield of sunflowers - Pine Ridge 2015-16

2015

Research organisaton
Funding sources

Trial details

Researcher(s) Loretta Serafin, Mark Hellyer and Peter Perfrement (NSW DPI)
Year(s) 2015
Contributor Department of Primary Industries NSW
Trial location(s) Site 3, Pine Ridge, NSW
Further information View external link
Related trials
Contribution of leaves to the yield of sunflowers - Pine Ridge 2015-16 locations
Aims

To quantify the contribution of sunflower leaves to yield and oil quality through the application of twelve leaf defoliation treatments.

Sunflowers are generally considered a minor crop in the NSW northern grains region.
However, they play an important role in providing a broadleaf summer crop rotation option.
An individual sunflower plant produces on average between 2000–6,000 cm2 of leaf area, which drives yield and oil content.
Identifying which leaves contribute most towards yield and oil content helps growers make
decisions about disease, pest and general crop management in sunflower crops. Whether it is
because the crop is infected with a disease such as powdery mildew or has insect damage e.g.
loopers, the end result is a need for growers and advisors to know where and when to spend
money in crop protection to achieve the best economic return on investment of maintaining
green leaf area.
This experiment was one of three sunflower leaf-loss sites conducted in the 2015–16 season, with the other sites being located at Gurley and Willow Tree.

Key messages
  • Sunflower grain yield averaged 1.07 t/ha at this site with the highest yields obtained from the control and the treatments where only the bottom one third (1/3) of leaves were removed.
  • The total leaf removal treatments had the largest effect on yield, at worst yielding only 0.16 t/ha.
  • Removing all leaves at budding or at the start of the flowering growth stages had the largest effect on plant structures.
  • Total leaf removal at the end of flowering had the largest effect on 1000 grain weight and test weight.
Lead research organisation Department of Primary Industries NSW
Host research organisation N/A
Trial funding source GRDC DAN00197
Trial funding source DPI NSW DAN00197
Related program Tactical agronomy for selected crops in the northern region (safflower, linseed, sunflower)
Acknowledgments

This experiment was part of the project Tactical agronomy for selected crops in the northern region (safflower, linseed, sunflower) (DAN00197), with joint investment by NSW DPI and GRDC. Thanks to Nuseed and Neil Weier for the supply of experiment seed. Technical assistance provided by Delphi Ramsden (NSW DPI), Angus Hombsch, Alice Bowler and Bronwyn Brennan (formerly NSW DPI) is gratefully acknowledged. Thanks also to Neroli Graham, NSW DPI for assisting with data analysis. Thanks to Peter Winton, ‘Windy Station’, Pine Ridge for hosting the experiment.


Other trial partners Peter Winton, ‘Windy Station’, Pine Ridge
Download the trial report to view additional trial information

Method

Crop type
Treatment type(s)
  • Crop
Trial type Experimental
Trial design Unknown

Pine Ridge 2015

Sow date 18 September 2015
Harvest date 17 February 2016
Plot size Not specified
Plot replication Not specified
Fertiliser <p>42 kg/ha Granulock Z applied at sowing</p>
Herbicide <p>Defoliation applied prior to harvest</p>
Other trial notes <p>Crop type: Sunflower (Hybrid: Ausigold 62)</p>
Download the trial report to view additional method/treatment information

Trial results Impact of defoliation treatments on plant structures

# Treatment 1
Head arc length (cm) Plant height (cm) Head diameter (cm)
1 Control - no leaves removed (0/3) 23.5 130.6 16.3
2 Budding - remove all leaves (3/3) 9.7 121.7 6.9
3 Budding - remove top 10 leaves (1/3) 24.1 132.1 17.7
4 Budding - remove top 20 leaves (2/3) 18.8 133.5 13.1
5 Budding - remove bottom 10 leaves (1/3) 24.3 136.5 15.7
6 Start of flowering - remove top 10 leaves (1/3) 24.5 135.1 17.1
7 Start of flowering - remove top 20 leaves (2/3) 19 128.7 15.6
8 Start of flowering - remove all leaves (3/3) 16.2 128.7 8.8
9 Start of flowering - remove bottom 10 leaves (1/3) 25.7 136.1 17.1
10 Flowering complete - remove top 10 leaves (1/3) 24.3 134.3 16.1
11 Flowering complete - remove top 20 leaves (2/3) 22.1 134 15.1
12 Flowering complete - remove all leaves (3/3) 22.5 129.1 13.1

Head arc length cm


Loading

Head diameter cm


Loading

Plant height cm


Loading
Observed trial site soil information
Trial site soil testing
Site Depth Type pH EC P K N A OC CAT
Site 3, Pine Ridge, NSW 0 - 10cm 7.49 53.00 2.33
Site 3, Pine Ridge, NSW 10 - 30cm 7.85 14.80 2.03
Site 3, Pine Ridge, NSW 30 - 60cm 8.11 23.90 1.92
Site 3, Pine Ridge, NSW 60 - 90cm 8.29 38.20 1.89
Site 3, Pine Ridge, NSW 90 - 120cm 9.07 48.70 1.80
Soil conditions
Trial site Soil texture
Site 3, Pine Ridge, NSW Not specified
Derived trial site soil information
Australian Soil Classification Source
Trial site Soil order
Site 3, Pine Ridge, NSW Anthroposol
National soil grid Source
NOTE: National Soil Grid data is aggregated information for background information on the wider area
Actual soil values can vary significantly in a small area and the trial soil tests are the most relevant data where available

Soil properties

Loading

Climate

Site 3, Pine Ridge NSW 2015


Observed climate information

Rainfall avg ann (mm) 668.9mm
Rainfall trial gsr (mm) 157mm

Derived climate information

Site 3, Pine Ridge NSW

NOTE: Exact trial site locality unknown - Climate data may not be accurate
Loading
Loading
Loading

Some data on this site is sourced from the Bureau of Meteorology

SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.

Trial report and links

2015 trial report