winter wheat to new heights
TRANSCRIPT
Causes of yield stagnation in winter wheat in Denmark. DFJ Report Plant Science no 147. November 2010. Petersen, J., Haastrup, M., Knudsen, L & Olesen, J.E.
80000
60000
40000
kg/h
year
HE
Causes of yield stagnation in winter wheat in Denmark
Farmers' biological knowledge? Do you go out from the tractor and check seed depth?
The size of the farm has increased . Do farmers activities in right time?
Soil compaction has become a severe problem?
Low prices and cost cutting!
Workshop 2012-08-21
• Control
• Crop establishment • Seed choice
• Soil conditions
• Fertilisation
• Management
SOIL: * Soil compaction * Drainage/irrigation * Humus content * Soil structure
NUTRIENTS: * N-application * P-status * K-status * Micro nutrients * Fertilisation precision * pH status/liming
SEED PREPARATION -OVERWINTERING * Seed preparation * Sowing time * Sowing depth * Seeding amount * Sowing technique
SEED - CHOICE: * Seed (yield, quality, disease resistance, etc.) * Healthiness * Cleanness (no weeds)
CROP PROTECTION: * Crop rotation * Weed * Fungi * Insects
MANAGEMENT * Timing * Machine capacity * Communication of already known knowledge * Competence (responsible for decisions, personal, entrepreneur..)
EXTERNAL FACTORS: * Regulation / laws * Permissible Inputs * Prices cereals & inputs
WEATHER & CLIMAT: *Temperature & precipitation
GROWTH REGULATOR
Influencing factors
The projects goal
• Identify knowledge gaps, new strategies, need for new research
• Identify causes why wheat yield has not increased
The yield increase should not be achieved at the expense of the farm profits or increased environmental impact.
Interviews of 32 farmers • A pair study, normal yield – high yields • Plus farms ~ 1000 kg more yield/ha • Comparable growing conditions • The hypothesis tested in the interview survey
of farmers was that "Some farmers are achieving higher yields because they have better management methods than others."
Hectares?
Labour planning?
Machinery?
Total financial cost?
Crop rotation?
Control strategies?
Fertilisation?
Your interest?
Education?
Enough labor?
Other sources of income? …………..? Potential yield?
Soil nutrient status?
Drainage status?
Expert literature review • Planting material • Soil preparation and crop establishment • Soil compaction • Drainage and irrigation • Fertilising and liming • Crop rotation and preceding crops • Weeds • Pests, • Weather, climate and models
Conclusions – plant materials
• New varieties that are better suited to different conditions urgently need to be developed, as a way to better exploit local resources.
• The growth of the ear during the period before
and immediately after flowering is crucial for winter wheat yield.
• There is also a need for more collaboration
between different research disciplines to achieve higher yields.
CROP ESTABLISHMENT
Several potentially crop yield-enhancing factors • sowing time, • seed rate • seedbed composition • seed placement (vertical and horizontal plane) .
Potential 0-10%.
Soil preparation
• Winter wheat can be grown successfully in systems with ploughing, in systems without ploughing and to some extent also in direct drilling systems.
POTENTIAL - SOIL COMPACTION/LOOSENING
• strongly dependent on the conditions at individual sites.
• the soil compaction/loosening effect can be expected to contribute an estimated yield increase of 0-15%
KNOWLEDGE GAPS - SOIL COMPACTION/LOOSENING • subsoil conditions for yield potential is unknown. • how to improve the long-term structure of the
subsoil and facilitate crop root development.
Spring Wheat 1 Barley 2 Winter Wheat 3 Spring Oilseed 4 Oat 5 Winter Oilseed 6 (Sugar beet) 7 Potato 8 Peas 9
Ranking of crops compaction resistance in topsoil
Source: Johan Arvidsson, SLU
• keeping the soil covered with vegetation • maintaining good drainage status; • minimising the number of passes, • lowering vehicle tyre pressure • trafficking in as dry conditions as possible • growing crops with deep roots • incorporating stabilising materials
Conclusions – Avoid subsoil compaction
Conclusion - drainage
Gammalstorp Gunnarstorp Lanna
Yield increase (in average 32 years trial) Drainage related to no drainage
Ley
Aut
umn
sow
ing
crop
s
Spr
ing
sow
ing
crop
s
Aver
age
The drainage system - conditions
• a need for a new drainage system on 14 % of Swedish Agricultural land.
• a need for a rebuilding of the drainage system on 15 % of Swedish Agricultural land.
Conclusions - irrigation
• In a global perspective - water scarcity • In a future perspective - drought may become
a major problem in Scandinavia • Sensitivity to water stress varies between
different stages of crop development. • Supplementary irrigation to optimise
production during dry years • Irrigation increase yield by 15-20 %
Conclusions – plant nutrients N
• Swedish trials show maximum 2-3 tonnes/ha higher than Swedish average
• A great potential for yield increases • Precision fertilisation, adapted to field
variations, increase yield by 3 %.
• N in right amount & time - soil mineralisation
• Fertilisation strategies - actual development stage of the crop, present-day varieties.
• Complement fertilisation not to early! Wheat have a compensation availability
• Can catch crops be used as a safety net in relation to high fertiliser and high yields.
A high yield can can be combined with a sustainable production – if balanced fertilisation
Illustrationer Hans von Corswant.
In order to carry out site-specific fertilisation and calculate the correct optimal nitrogen requirements • better crop forecasting and predictions of soil
mineralisation are needed. • practical techniques and fertilisation models must be
developed, - the use of zero and maximum test areas - ”N-sensor is the best technical invention during the last time”
Phosphorous, pH, micronutrients…
• avoid having too low a phosphorus content (P <6) or pH (< 6.3) in the soil.
• Phosphorus fertilisation of soils with low P values and liming on soils with low pH must to be encouraged to increase the potential for higher yield.
• Micronutrient
Winter Wheat Yield due to Preceding crops & N-application rate
(9 trials in SkĂĄne)
3000
4000
5000
6000
7000
8000
9000
10000
0 50 100 150 200 250 300
Kväve kg/ha
Hös
tvet
eskö
rd,
kg/h
a,15
% v
h
Förfrukt: höstrapsFörfrukt: havreFörfrukt:ärter
700 kg/ha higher yields after winter rape seed and peas
Win
ter W
heat
Yie
ld k
g/ha
, 15
% m
oist
ure
Nitrogen kg N/ha
Preceding crop, winter rape seed Preceding crop, oat Preceding crop, pea
Conclusions preceding crops
• A good preceding crop, yield is on average 1 ton higher than with winter
wheat as the preceding crop. • But the effect of a preceding crop is difficult to explain or predict, and varies
greatly depending on the local conditions. The long-term effect of ley in the crop rotation is certainly important, but difficult to quantify.
• If 20% of the winter wheat could be grown with better preceding crop than today, the wheat production in Sweden will increase by 3%.
• Knowledge gap, a satisfactory descriptions of the importance of crop
rotation and cropping system.
Conclusions - weed • The declining yield increases in Sweden
cannot be explained by increased problems with weeds. Danish study, same conclusion.
• But – the effect of chemical weed control, in particular against grass weeds, will decrease in the future, unless a greater focus is put on integrated control strategies.
• The number of selective herbicides against grass weeds is limited.
Conclusions - weed • major problems with resistance in some grass
weeds. UK, resistant populations of blackgrass Alopecurus myosuroides on 2,000 farms.
Blackgrass, plants/m-2
Yield losses, %
12 5
25 10
50 15
100 35
250 35
500 50
FrĂĄn Blair, Cussans & Lutman, 1999
Conclusions - weed The prompt reads thus: • Do not let grass weeds take over. Protect
existing assets. • Prevent herbicide resistance from developing
by using Integrated Pest Management (IPM).
Conclusions – pest • Plant pests cause quantitative and qualitative yield losses every year. The actual pest
responsible for most losses and the size of the losses vary between years and sites. • In the 2009/10 season, (SCB 2012).
– 70% of Swedish winter wheat was treated with fungicides, – 33% with insecticides – 94% with herbicides
• Field trials showed that the effect of fungicide treatment on fungal diseases in winter
wheat ranged from marginal to large. Taking into account the cost of fungicide treatment, it is thus not always profitable for the farmer. Profitability is strongly influenced by the wheat winter price, where the crop is grown and the actual weather conditions.
• The most common insect pests in winter wheat, wheat grain aphid (Macrosiphum avenae ) and wheat blossom midge (Contarinia tritici), are not a limiting factor for winter wheat yield at present.
• There is no evidence that increased attacks by pests or deteriorating effects of
fungicides (strobilurins and triazoles) are the main cause of the recent stagnation in winter wheat yields in Sweden. Denmark has come to the same conclusion.
Differences between the farms (examples)
• Right decisions at the right time based on right priorities
• A higher awareness of management's role
• Good planning in terms of extra staff
• Slightly higher P-status • Slightly higher pH-status • Slightly better crop rotation • Tyre pressures on machines
were lower • Higher nitrogen use efficiency • A more balanced fertilisation
• Some field activities at wrong time
• More soil compaction, more are experiencing soil compaction as a problem
• More common with reseeding
• More indicates that it is more important to keep costs down than to get high harvest
High yields Normal yields
Conclusions management
• The overall reason why plus farms achieved higher yield was better management, defined as the ability to make the right decisions at the right time and to prioritise correctly between various tasks.
Conclusions – management: The plus farms surveyed were better able to balance all their crop production decisions in an effective manner. The plus farms are probably more aware of the impact a decision can have on other parts of the business.
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You can download the Winter Wheat book (in Swedish) from www.odlingibalans.com