Hyper Yielding Cereal Project - what has performed well over two contrasting seasons?

Take home messages

  • In 2017 second year research results from the Hyper Yielding Cereals (HYC) project produced maximum yields of wheat of 13t/ha with above average temperatures during grain fill and a generally harder finish.
  • With the barley research, despite two contrasting seasons the same three cultivars topped the yield rankings, these were RGT Planet, RGT Conquest and the faster developing cultivar Rosalind.
  • Shorter season wheat cultivars Annapurna and AGTW001 performed well irrespective of sowing date with similar or higher yields to last year’s high fliers; RGT Relay, RGT Accroc, Genius, Conqueror and RGT Calabro at the first sowing date in early April.
  • RGT Relay again showed good standing power and excellent Septoria tritici blotch (STB); Zymoseptoria tritici resistance but showed good yield responses to late fungicide control of leaf rust; Puccinia triticina.
  • RGT Accroc has produced high yields in both 2016 and 2017 but again showed a weakness in straw strength.
  • From the 2017 results it was difficult to establish a clear relationship between optimum flowering date and final yields since cultivars flowering from late October to mid November produced good yields. In part this may be related to the impact of irrigation which tends to assist cultivars that might otherwise be penalised in a dryland system because of their later development.

ɸExtra technical comment by Protech Consulting Pty Ltd

Background

Despite a more suitable climate for grain production than the mainland and a much higher yield potential, the average yield of red grain feed wheat in Tasmania is still around 5t/ha. While this has increased relatively more than the other states in the last 20 years (ABARES) it is still felt to be well below the potential.

The Hyper Yielding Cereals (HYC) project funded by GRDC and led by FAR Australia in collaboration with Southern Farming Systems (SFS) aims to make Tasmania less reliant on grain supplied from mainland Australia through increased productivity of wheat and barley. Using the collaboration of international, national, local expertise and breeders, the five-year project is working to close the yield gap between actual and potential yields as well as using links with end users to promote the value of trading quality feed grains.

In 2017 the Hyper Yielding research centre at Hagley, Tasmania was composed of 1000 experimental research plots dedicated to identifying new cereal lines and agronomy strategies that could lift feed grain productivity.

In 2016 first year research results from the project set new benchmarks for the yield performance of feed wheat with plot yields in excess of 15t/ha. The soft finish and high rainfall experienced during 2016 was in stark contrast to 2017 when low rainfall, higher temperatures and late frosts affected the grain fill period. In many ways the contrast of the 2016 and 2017 seasons has been useful in determining which new cultivars and lines have performed well in both seasons.

2016 and 2017 climatic conditions

2017 differed in three principal ways from 2016 at the Hyper Yielding research centre; firstly, instead of warmer temperatures over autumn and early winter, cooler minimum temperatures prevailed (Figure 1a and 1b). One of the primary initial effects was to slow down growth from the late April sown crops (27 April) relative to those sown early in April (6 April). It also resulted in significantly less leaf rust infection (Puccinia triticina) in the early wheat sowings, a fact that appeared to indicate the importance of autumn infection in order to generate severe leaf rust infections in Tasmania.

Despite the late leaf rust infection, the disease did not influence research results at the centre. Secondly, the temperatures for the grain fill period for the wheat crops in particular, was well above the long-term maximums for Tasmania. In November these high temperatures combined with below average rainfall, made it difficult for on-farm irrigation systems to keep up with soil water demand. Lastly, although regions were affected by frost during flowering and early grain fill, results were not severe at the research site as elsewhere in the state, although grain sample screenings were increased from an average of 1.5 to 2.0% in 2016 to between 4 to 6% in 2017.

Line and bar graphs showing 2016 climatic data including long term and annual rainfall, and minimum and maximum temperatures for the Hyper Yielding Cereal site at Hagley, Tasmania

Figure 1(a). 2016 climatic data for the Hyper Yielding Cereal site at Hagley, Tasmania.

Line and bar graphs showing 2017 climatic data including long term and annual rainfall, and minimum and maximum temperatures for the Hyper Yielding Cereal site at Hagley, Tasmani

Figure 1(b). 2017 climatic data for the Hyper Yielding Cereal site at Hagley, Tasmania.

Research conducted in 2017

A series of 10 field research trials covering 1000 plots were established in Year 2 to service germplasm screening and the agronomy objectives of the project. The initial 16 cultivars/lines provided by the breeders for the early sowing window (6 April) were narrowed down to four, with a further 16 cultivars that had not been sown early in 2016 tested at this sowing date for the first time. These 16 cultivars evaluated for the first time in 2017 either showed promise in the later sowing (27 April) last year or were thought to have been more suitable for early sowing due to longer season phenology (established in year 1). The four core elite cultivars plus the controls SQP Revenue and Manning were run under three different management approaches in order to further reveal their suitability or otherwise for the early April sowing date.

The three management levels of input were i) grazed (mechanically defoliated twice) with standard input ii) standard input alone and iii) high input where extra nitrogen, plant growth regulators (PGRs) and fungicide input were applied. The trial resulted in a significant (p=<0.001) interaction between cultivar and management applied (Table 1 and 2), meaning that cultivars responded differently to the management regimes imposed. The yields of the four elite cultivars selected from 2016 yielded between 10.02 to 11.66t/ha. The top yield of 11.66 t/ha (RGT Accroc) was 2.78t/ha less than the highest yield achieved in 2016 when RGT Relay yielded 14.44t/ha at the early sowing date. RGT Accroc was significantly higher yielding where it was grazed or treated with higher input, a result principally correlated to lower lodging in these two management regimes.

In contrast, in the stiffer strawed, slower developing, more disease resistant variety RGT Relay there were no significant differences in yield amongst the three management regimes applied, with less than 0.3t/ha difference in the three strategies. In part the slower development resulted in reduced dry matter removal from the ‘grazed’ plots and extra PGR input was not required. At the early sowing date in 2017 Relay yielded 3t/ha less than 2016.

SQP Revenue was the only cultivar to give significantly higher yields under grazing management, a result that correlated to lower levels of lodging and lower disease pressure in these defoliated crops. Protein levels were mainly in the range of 10.7 to 11.1% suggesting that yield was optimised for the site with the nitrogen levels applied. There were no significant effects of management strategy on the quality parameters of protein, test weight or screenings, but results on test weight were very variable and indicated some possible frosting damage.

Table 1. Grain yield (t/ha), % Site Mean, Protein, test weight and screenings of the elite wheat germplasm under three management levels, sown 6 April, harvested 23 January.

  Grain yield Grain quality

Management level

Variety

Yield
(t/ha)

Site mean
(%)

Protein
(%)

Test wt
(Kg/hL)

Screenings
(%)

High

Manning

11.50

ab

106.3

11.0

a-e

75.8

a

3.3

ab

SQP Revenue

9.32

g

86.2

10.5

de

72.7

ab

4.6

a

Genius

11.35

abc

105.0

10.9

a-e

71.4

ab

4.5

a

Conqueror

11.53

ab

106.7

11.1

a-d

70.2

ab

3.8

ab

RGT Accroc

11.66

a

107.8

10.9

a-e

75.5

a

3.2

ab

RGT Relay

11.29

abc

104.5

11.2

abc

70.8

ab

3.8

ab

Mean

11.11

a

102.7

10.9

a

72.7

a

3.9

a

Standard

Manning

11.28

abc

104.0

11.3

abc

74.8

a

3.9

ab

SQP Revenue

8.75

h

80.9

10.7

b-e

75.2

a

3.4

ab

Genius

11.32

abc

104.6

10.8

b-e

71.3

ab

4.5

a

Conqueror

11.33

abc

104.5

11.5

a

75.2

a

3.6

ab

RGT Accroc

10.59

e

97.8

11.3

ab

71.5

ab

2.5

b

RGT Relay

11.45

abc

105.6

11.0

a-e

73.6

a

3.9

ab

Mean

10.78

b

99.6

11.1

a

73.6

a

3.7

a

Grazed

Manning

10.82

de

99.8

10.6

cde

75.7

a

4.4

a

SQP Revenue

9.81

f

90.5

10.5

de

71.4

ab

4.2

a

Genius

10.02

f

92.6

10.4

e

70.2

ab

4.3

a

Conqueror

10.60

e

97.9

11.1

a-d

72.5

ab

4.3

a

RGT Accroc

11.07

cd

102.2

10.9

a-e

67.5

b

3.2

ab

RGT Relay

11.18

bcd

103.3

11.1

a-d

69.9

ab

3.5

ab

Mean

10.58

b

97.7

10.7

a

71.2

a

4.0

a

Mean (High)

11.11

a

102.7

10.9

a

72.7

a

3.9

a

Mean (Standard)

10.78

b

99.6

11.1

a

73.6

a

3.7

a

Mean (Grazed)

10.58

b

97.7

10.7

a

71.2

a

4.0

a

LSD Mgmt p = 0.05

0.28

-

0.4

4.5

0.7

LSD Variety p = 0.05

0.23

-

0.4

3.4

0.9

LSD Var x Mgmt P=0.05

0.40

-

0.7

5.9

1.6

P Val Mgmt

0.011

-

0.238

0.458

0.562

P Val Variety

<0.001

-

0.011

0.116

0.080

P Val Var x Mgmt

<0.001

-

0.841

0.456

0.861

CV

2.6

-

4.4

5.8

29.5

Notes: Figures followed by different letters are considered to be statistically different (p=0.05)

Letters following mean figures in bold are only comparable to other bold letters in the same column/row.

The input levels for the three management regimes for the 6 April sowing date are outlined in Table 2.

Table 2. Detail of management levels applied to the Management x Cultivar trial – sown 6 April
Sowing date: 6 April
Plant population: Target of 180 plants/m2 (mean of 116 plants/m2 established)
Sowing fertiliser: 100kg MAP

Management

Date

High

Standard

Grazed

Grazing

-

-

-

17-May and 14-Aug

Nitrogen

27 July

46kg N

46kg N

46kg N

31 August

160kg N

92kg N

92kg N

19 September

92kg N

92kg N

92kg N

PGR

9 August

Moddus Evo 200ml and Errex 650ml

-

-

19 September

Experimental 1

Moddus Evo 200ml and Errex 1300ml

Moddus Evo 200ml and Errex 1300ml

3 October

Experimental 2

-

-

Fungicide

9 August

Opus125 500ml

-

-

6 September

-

Opus125 500ml

Opus125 500ml

19 September

Prosaro 300ml and Hasten 1%ɸ v/v

-

-

20 October

Radial 840ml

Radial 840ml

Radial 840ml

11 November

Prosaro 300ml

Prosaro 300ml

Prosaro 300ml

Insecticide

15 May

Karate Zeon 0.04L/ha + Kontrace 3.0L/ha

5 June

Karate Zeon 0.04L/ha + Kontrace 2.4L/ha

Irrigation

23 October

18mm

30 October

17mm

9 November

25mm

29 November

18mm

30 November

16mm

20 December

25mm

ɸTrial purposes only as label states that Hasten is only for use with Prosara at 150ml. In commercial situations please adhere to label recommendations

In neighbouring trials looking at the 16 cultivars sown at the same early April sowing, yield results and phenology data revealed some surprising results with more rapid developing cultivars, such as AGTW001 and Annapurna either outperforming or giving comparable performance to the longer season elite lines selected from 2016 (Table 3), even though the flowering phenology of the cultivars was far earlier. Only RGT Accroc, Annapurna and AGTW001 had passed the mid flower point (GS66-71) on 1 November.

All other cultivars in Table 3 were at various stages of head emergence (GS51-59) with the exception of RGT Relay that was still at the late booting stage and did not start flowering until 17 November. RGT Calabro was at GS59 (full head emergence) on 1 November. The poor quality of the samples is part a reflection of partial frosting and partially the particular plot header. One of the major considerations for the early sowing window is stiff straw and good disease resistance when sowing early.

Since many of the cultivars tested on 6 April 2017 had not been tested at this sowing date in 2016 the varieties were also grown in an untreated screen with no PGR and fungicide applied. Only the cultivars that lodged in this screen or in the yield trials sown at the same time are featured in Figure 2.

Table 3. Grain yield (t/ha), % Site Mean, % grain protein and % screenings

Cultivar/line

Yield
(t/ha)

% Site mean

Protein
(%)

Screenings
(%)

Lodging index
(0-500)

Annapurna

13.01

a

112.5

11.3

bcd

5.4

bcd

16

de

AGTW-001

12.66

ab

109.6

11.3

bcd

4.8

cd

2

e

RGT Calabro

12.47

abc

107.9

11.7

a-d

5.1

bcd

40

cde

Genius

12.44

abc

107.6

12.3

ab

5.7

a-d

0

e

Manning

12.25

bc

106.0

10.8

d

5.6

bcd

15

de

RGT Accroc

12.17

bcd

105.3

11.8

a-d

7.4

abc

68

cde

Conqueror

11.99

b-e

103.7

12.6

a

6

a-d

0

e

JB Asano

11.86

c-f

102.6

12.0

abc

5.4

bcd

0

e

Einstein

11.78

c-f

101.9

11.5

bcd

4.1

d

1

e

BA 26.35

11.49

def

99.4

11.5

a-d

4.7

d

0

e

Mercedes

11.46

ef

99.1

11.3

bcd

7.6

ab

83

cd

RGT Relay

11.44

ef

98.9

11.3

bcd

6.2

a-d

0

e

Viscount

11.20

fg

96.9

11.7

a-d

7.5

ab

64

cde

Oakley

10.52

gh

91.0

11.0

cd

6.5

a-d

113

c

Hereford

10.51

gh

90.9

11.3

bcd

5.1

bcd

1

e

Xi 19

10.36

h

89.6

11.3

bcd

4.2

d

20

de

SQP Revenue

9.95

h

86.0

11.6

a-d

4.7

d

205

b

Cordiale

9.87

h

85.4

11.2

bcd

8.2

a

293

a

Mean

11.522

100

11.51

5.79

50.97

LSD p = 0.05

0.704

-

1.13

2.62

78.38

P value

<0.001

-

0.285

0.054

<0.001

Bar graph illustrating the lodging index (severity x extent – 0 to 500 scale) of a number of different cultivars trialled under both the standard and high input management and in the untreated screening trial (with PGR or fungicide) assessed on the 23-24 January just prior to harvest (GS99).

Figure 2. Lodging index (severity x extent – 0 to 500 scale) of cultivars trialled under both the standard and high input management and in the untreated screening trial (with PGR or fungicide) assessed on the 23-24 January just prior to harvest (GS99). Note. Other varieties not shown did not suffer lodging.

Disease resistance when sowing early

The same untreated screen gave an excellent insight into Septoria tritici blotch, Zymoseptoria tritici susceptibility when cultivars were sown in the highest risk sowing window (Figure 3). The screen was less reliable in 2017 for generating good leaf rust differences, however there was one exception to this general observation. This concerned RGT Relay that provided excellent STB resistance and stiff straw but did succumb to a very late infection of leaf rust that was not apparent in mid-December 2017, which resulted in significant yield reduction when not controlled (Table 5).

Samples of the pathogen on RGT Relay did not reveal a new pathotype as the sample sent was not viable, but both yield and green leaf area were affected by the new year infection timing. At the same time (Jan 5) RGT Accroc, RGT Calabro and Annapurna had in the main, reached physiological maturity. This is an important observation for RGT Relay grown under irrigation, since later cultivar development combined with irrigation may make it particularly responsive to late fungicides for leaf rust control. Similar findings have been observed in New Zealand for similar cultivars grown under irrigation.

Bar graph illustrating the disease severity of Septoria tritici blotch (STB) (whole plot score), assessed on 23 August (GS26-32), 21 September (GS31-51) and 01 November (GS47-71) on a number of different cultivars.

Figure 3. Disease severity of Septoria tritici blotch (STB) (whole plot score), assessed on 23 August (GS26-32), 21 September (GS31-51) and 01 November (GS47-71)

Yield potential of early versus late April sowing (6 April versus 27 April) – which was higher yielding in 2017?

In 2016 the late (27 April) sown wheat trials were 2 to 3t/ha higher yielding than the early (6 April) sown wheat trials, with yields in excess of 16t/ha at the later sowing date. A soft finish and higher leaf rust pressure affecting the early sowings appeared to be two primary considerations in 2016 affecting yield. This raises the question whether under a shorter growing season in 2017 with a hotter grain fill period in November was there any advantage to 6April sowing compared with 27 April sowing growing irrigated wheat at the research centre? Although trials were in the same paddock the following results cannot be statistically compared but represent the best yields from both sowing dates (Table 4).

The differences between the two sowing dates in 2017 was relatively small (0.3t/ha) with 13t/ha achieved in both sowing date blocks, and in both cases the same shorter season wheat cultivars were the optimum performers despite the differences in estimated flowering dates between the two sowings. Unfortunately, AGTW001 has been discontinued by the breeder since its stem rust resistance was very poor and not acceptable for the mainland, however Annapurna has been carried through for more detailed agronomy evaluations at the site for 2018/19.

At both sowing dates it was difficult to suggest a strong relationship between flowering date and final yield since at the first sowing date Genius and RGT Calabro performed similarly to AGTW001 in terms of yield, but were considerably later to flower than AGTW001. At the second sowing date the differences between flowering dates was much smaller however AGTW001 and Annapurna performed significantly better than RGT Accroc and RGT Calabro (Table 4).

The exact timing of the late frosts interacting with both flowering date and cultivar may help explain some of these differences but it is worth indicating that irrigation itself may obviate some of the differences that might be commonly seen with regard to optimum flowering dates and the relationship with yield in dryland crops. That stated the Tasmanian NVT results for wheat sown in late April/early May concur with the Hyper yielding performance results indicating high yields from RGT Accroc and RGT Calabro.

Table 4. Grain yield (t/ha), % Site Mean, % grain protein and % screenings of the top five cultivars sown in trials on 6 and 27 April.

Sowing date 1

Cultivar/line

Yield
(t/ha)

% Site mean

Protein
(%)

Screenings
(%)

Estimated flowering
(GS65)

6 April

Annapurna

13.01

113

11.3

5.4

L.Oct

AGTW-001

12.66

110

11.3

4.8

L.Oct

RGT Calabro

12.47

108

11.7

5.1

E.Nov

Genius

12.44

108

12.3

5.7

M.Nov

Manning (control)

12.25

106

10.8

5.6

M.Nov

RGT Accroc

12.17

105

11.8

7.4

L.Oct

Conqueror

11.99

104

12.6

6

E.Nov

SQP Revenue (control)

9.95

86

11.6

4.7

E.Nov

Mean

12.1

-

11.7

5.6

-
Sowing date 2

Cultivar/line

Yield (t/ha)

% Site mean

Protein (%)

Screenings (%)

Estimated Flowering (GS65)

27 April

AGTW - 001

13.10

116

12.7

3.3

M.Nov

Annapurna

12.81

113

12.3

3.5

E.Nov

RGT Accroc

12.14

107

12

3.3

M.Nov

AGTW - 002

12.03

107

12.6

3.8

E.Nov

RGT Calabro

12.01

106

12.4

2.8

M.Nov

Conqueror

11.53

102

12.3

2.7

M.Nov

Manning (control)

10.80

96

12.3

3

L.Nov

SQP Revenue (control)

10.00

89

11.8

4.2

M.Nov

Mean

11.8

-

12.3

3.3

-

The lack of a relationship between flowering date and yield in these irrigated trials was further confounded by the performance of RGT Relay in the early sown fungicide and nitrogen research trials. These trials produced maximum yields of 12.5 to 13.0t/ha, despite a mid-November flowering date (Table 5). As stated earlier RGT Relay while being very resistant to STB, succumbed to a late leaf rust infection in the new year. Samples sent for pathotying were not viable so it remains to be seen whether this is a new issue, however it was not observed in 2016 when early leaf rust pressure was much higher. In 2017 control of late leaf rust gave significant benefits to fungicide programmes based on triazoles, SDHI and strobilurin as opposed to triazole alone.

Table 5. Grain yield (t/ha), % Site Mean, % grain protein, test weight (kg/hl) and % screenings (selected treatments from larger trial)

Cultivar

Fungicide product, rate (mL/ha) and timing

Yield
(t/ha)

Mean
(%)

Protein
(%)

Test wt.
(kg/hL)

Screenings
(%)

GS31-32

GS39

GS61-65

RGT Accroc

Untreated

--

10.23

de

102.3

11.4

a

71.9

a

4.8

bcd

Hornet 145

Opus 500

Hornet 145

10.83

c

108.3

11.6

a

71.2

ab

4

cde

Aviator Xpro 420

Radial 840

Prosaro 300

10.94

c

109.4

11.8

a

72.3

a

3.6

e

RGT Relay

Untreated

--

10.51

cd

105.1

10.8

b

67.1

b-e

3.7

e

Hornet 145

Opus 500

Hornet 145

11.67

b

116.7

10.7

b

70.7

ab

3.3

e

Aviator Xpro 420

Radial 840

Prosaro 300

12.62

a

126.2

10.6

b

68.9

abc

3.7

de

SQP Revenue

Untreated

--

8.09

g

80.9

10.4

b

63.1

e

5.7

ab

Hornet 145

Opus 500

Hornet 145

9.15

f

91.5

10.4

b

65.6

cde

5.2

b

Aviator Xpro 420

Radial 840

Prosaro 300

9.84

e

98.4

10.5

b

63.8

de

5.4

ab

LSD 0.05

 

0.486

-

0.523

4.57

1.06

P Val

 

<0.001

-

<0.001

0.001

<0.001

Higher barley yields compared to 2016

Unlike the wheat trials where yields during 2017 were back to 13t/ha from maximums of 16 to 17t/ha in 2016, the shorter growing season with a hotter grain fill period favoured barley performance at the site. In 2016 the highest yields were generated by RGT Planet, RGT Conquest, and Rosalind in a soft finish. In 2017 despite a season in stark contrast to 2016 the same three cultivars topped the performance charts but this time with a harder finish and higher yields overall. The different rotation position of ex pyrethrum may have helped, compared to process peas in 2016, however the results were very encouraging not only because of the consistency of variety performance but also the production of yields in excess of 11t/ha.

In the 2018/19 season the HYC project will undertake in depth, agronomic research on the following wheat cultivars: Annapurna, DS Bennett and the RGT lines Accroc, Calabro and Relay (sown 5 April and 26 April, 2018). With the barley component of the research, new winter germplasm sown at the same time is being tested alongside RGT Planet, RGT Conquest and Rosalind for the very first time.

Come and view the research on Thursday November 15, 2018!

Acknowledgements

The research undertaken as part of this project is made possible by the significant contributions of growers through both trial cooperation and the support of the GRDC — the authors would like to thank them for their continued support.

Contact details

Nick Poole
23 High St, Inverleigh, Victoria 3221
0499 888 066
nick.poole@faraustralia.com.au

Tracey Wylie
23 High St, Inverleigh, Victoria 3221
0499 888077
tracey.wylie@faraustralia.com.au

GRDC Project code: FAR00003