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CONTEXT: Summer crops are exposed to heat and drought stresses at critical stages during and after flowering, and their intensity and frequency are likely to increase with climate change. Agronomic stress avoidance offers the opportunity to temporally separate critical crop stages from heat and drought events, though it might require sowing cold sensitive summer crops early in late winter into colder than recommended soil temperatures. There is a need to understand how cold is too cold to sow summer crops early in late winter as well as what are the yield benefits and risks. OBJECTIVE: Here we quantify the likely benefits and trade-offs of sowing sorghum, a summer cereal, early in late winter as an adaptation to the increased frequency and intensity of heat and water stresses during flowering and grain filling.

CONTEXT: Summer crops are exposed to heat and drought stresses at critical stages during and after flowering, and their intensity and frequency are likely to increase with climate change. Agronomic stress avoidance offers the opportunity to temporally separate critical crop stages from heat and drought events, though it might require sowing cold sensitive summer crops early in late winter into colder than recommended soil temperatures. There is a need to understand how cold is too cold to sow summer crops early in late winter as well as what are the yield benefits and risks. OBJECTIVE: Here we quantify the likely benefits and trade-offs of sowing sorghum, a summer cereal, early in late winter as an adaptation to the increased frequency and intensity of heat and water stresses during flowering and grain filling.

CONTEXT: Summer crops are exposed to heat and drought stresses at critical stages during and after flowering, and their intensity and frequency are likely to increase with climate change. Agronomic stress avoidance offers the opportunity to temporally separate critical crop stages from heat and drought events, though it might require sowing cold sensitive summer crops early in late winter into colder than recommended soil temperatures. There is a need to understand how cold is too cold to sow summer crops early in late winter as well as what are the yield benefits and risks. OBJECTIVE: Here we quantify the likely benefits and trade-offs of sowing sorghum, a summer cereal, early in late winter as an adaptation to the increased frequency and intensity of heat and water stresses during flowering and grain filling.

Take home message • Nitrogen derived from atmosphere (Ndfa) in mungbean crops is strongly influenced by the amount of mineral soil nitrates that are available at planting. There is an almost linear decline in N2 fixation as soil nitrates increase in the top 60cm of the profile. • Mungbean and chickpea crops can access and utilise soil nitrate N in the top 60cm as efficiently as cereal crops. This raises implications for nitrate N supply in crops following these pulse crops. • Mungbeans planted in long fallow situations will create a soil nitrate N deficit as N2 fixation rates cannot replace the amount of soil nitrate being exported in grain. Circumstantial evidence suggests that chickpeas may be similar.

Take home messages The nitrogen (N) fertiliser demand for cereal cropping systems can increase due to two factors: 1. A reduction in the amount of soil organic N mineralised due to the continued decline of natural capital (soil organic carbon and total nitrogen) that occurs under cropping; and 2. An increased crop N demand due to higher yield potentials resulting from optimising other components of the cropping system. The amount of biological N fixation by pulse crops (chickpea/mungbean) is related to the crop yield and biomass and the availability of soil mineral N from mineralisation or carry-over of residual fertiliser. Where deep phosphorus (P) and potassium (K) application increases chickpea biomass (and grain yield), there is generally more N fixed. While some of this is re-exported in grain, the greater residue return means more N is carried forward to the next crop. Growers have a selection of fertiliser N management practices that have differing strengths and weaknesses – it is not a one-size-fits-all model for CQ (or northern region) farming systems. The 4R framework allows choice of rate, source, time and place for any nutrient applied to be implemented suiting each growers’ preferences, with on-going research addressing several themes in regional Qld.

The relative time to maturity of grain crops is an important consideration for producers, yet there are no universally accepted classification schemes for cultivar phenology to guide decisions on variety selection and time of sowing. A first edition of an industry guide for wheat variety maturity was recently developed for use across Australia, representing a significant step forward for the grains industry. The aim of this paper was to revise and extend this industry guide to make it more robust, agronomically functional and meaningful to industry. The Australian Cereal Phenology Classification (ACPC) presented herein was developed using an unprecedented phenological data set with a diverse array of genotypes, environments and management. Field experiments were carried out with 70 wheat and 30 barley cultivars at 15 sites across Australia between 2017 and 2020. Thermal time to anthesis data were used to rank cultivars according to their relative phenology and divide them into classes, and then boundary cultivars of both species were selected to separate these classes. The resulting classification scheme divides wheat and barley into phenology classes ranging from ‘quick’ to ‘mid’ to ‘slow’. New cultivars to market can be assigned a phenology classification based on their thermal time to anthesis relative to the boundary cultivars. The ACPC will help growers, agronomists, breeders and researchers make informed decisions regarding cultivar comparison and selection while reducing misclassification and confusion across regions. The same methodology used to derive and validate the ACPC can be applied internationally to standardise descriptions of crop phenology.

The relative time to maturity of grain crops is an important consideration for producers, yet there are no universally accepted classification schemes for cultivar phenology to guide decisions on variety selection and time of sowing. A first edition of an industry guide for wheat variety maturity was recently developed for use across Australia, representing a significant step forward for the grains industry. The aim of this paper was to revise and extend this industry guide to make it more robust, agronomically functional and meaningful to industry. The Australian Cereal Phenology Classification (ACPC) presented herein was developed using an unprecedented phenological data set with a diverse array of genotypes, environments and management. Field experiments were carried out with 70 wheat and 30 barley cultivars at 15 sites across Australia between 2017 and 2020. Thermal time to anthesis data were used to rank cultivars according to their relative phenology and divide them into classes, and then boundary cultivars of both species were selected to separate these classes. The resulting classification scheme divides wheat and barley into phenology classes ranging from ‘quick’ to ‘mid’ to ‘slow’. New cultivars to market can be assigned a phenology classification based on their thermal time to anthesis relative to the boundary cultivars. The ACPC will help growers, agronomists, breeders and researchers make informed decisions regarding cultivar comparison and selection while reducing misclassification and confusion across regions. The same methodology used to derive and validate the ACPC can be applied internationally to standardise descriptions of crop phenology.

The relative time to maturity of grain crops is an important consideration for producers, yet there are no universally accepted classification schemes for cultivar phenology to guide decisions on variety selection and time of sowing. A first edition of an industry guide for wheat variety maturity was recently developed for use across Australia, representing a significant step forward for the grains industry. The aim of this paper was to revise and extend this industry guide to make it more robust, agronomically functional and meaningful to industry. The Australian Cereal Phenology Classification (ACPC) presented herein was developed using an unprecedented phenological data set with a diverse array of genotypes, environments and management. Field experiments were carried out with 70 wheat and 30 barley cultivars at 15 sites across Australia between 2017 and 2020. Thermal time to anthesis data were used to rank cultivars according to their relative phenology and divide them into classes, and then boundary cultivars of both species were selected to separate these classes. The resulting classification scheme divides wheat and barley into phenology classes ranging from ‘quick’ to ‘mid’ to ‘slow’. New cultivars to market can be assigned a phenology classification based on their thermal time to anthesis relative to the boundary cultivars. The ACPC will help growers, agronomists, breeders and researchers make informed decisions regarding cultivar comparison and selection while reducing misclassification and confusion across regions. The same methodology used to derive and validate the ACPC can be applied internationally to standardise descriptions of crop phenology.

The relative time to maturity of grain crops is an important consideration for producers, yet there are no universally accepted classification schemes for cultivar phenology to guide decisions on variety selection and time of sowing. A first edition of an industry guide for wheat variety maturity was recently developed for use across Australia, representing a significant step forward for the grains industry. The aim of this paper was to revise and extend this industry guide to make it more robust, agronomically functional and meaningful to industry. The Australian Cereal Phenology Classification (ACPC) presented herein was developed using an unprecedented phenological data set with a diverse array of genotypes, environments and management. Field experiments were carried out with 70 wheat and 30 barley cultivars at 15 sites across Australia between 2017 and 2020. Thermal time to anthesis data were used to rank cultivars according to their relative phenology and divide them into classes, and then boundary cultivars of both species were selected to separate these classes. The resulting classification scheme divides wheat and barley into phenology classes ranging from ‘quick’ to ‘mid’ to ‘slow’. New cultivars to market can be assigned a phenology classification based on their thermal time to anthesis relative to the boundary cultivars. The ACPC will help growers, agronomists, breeders and researchers make informed decisions regarding cultivar comparison and selection while reducing misclassification and confusion across regions. The same methodology used to derive and validate the ACPC can be applied internationally to standardise descriptions of crop phenology.

Take home messages The nitrogen (N) fertiliser demand for cereal cropping systems can increase due to two factors: 1. A reduction in the amount of soil organic N mineralised due to the continued decline of natural capital (soil organic carbon and total nitrogen) that occurs under cropping; and 2. An increased crop N demand due to higher yield potentials resulting from optimising other components of the cropping system. The amount of biological N fixation by pulse crops (chickpea/mungbean) is related to the crop yield and biomass and the availability of soil mineral N from mineralisation or carry-over of residual fertiliser. Where deep phosphorus (P) and potassium (K) application increases chickpea biomass (and grain yield), there is generally more N fixed. While some of this is re-exported in grain, the greater residue return means more N is carried forward to the next crop. Growers have a selection of fertiliser N management practices that have differing strengths and weaknesses – it is not a one-size-fits-all model for CQ (or northern region) farming systems. The 4R framework allows choice of rate, source, time and place for any nutrient applied to be implemented suiting each growers’ preferences, with on-going research addressing several themes in regional Qld.

Take home message • Nitrogen derived from atmosphere (Ndfa) in mungbean crops is strongly influenced by the amount of mineral soil nitrates that are available at planting. There is an almost linear decline in N2 fixation as soil nitrates increase in the top 60cm of the profile. • Mungbean and chickpea crops can access and utilise soil nitrate N in the top 60cm as efficiently as cereal crops. This raises implications for nitrate N supply in crops following these pulse crops. • Mungbeans planted in long fallow situations will create a soil nitrate N deficit as N2 fixation rates cannot replace the amount of soil nitrate being exported in grain. Circumstantial evidence suggests that chickpeas may be similar.

Take home messages The nitrogen (N) fertiliser demand for cereal cropping systems can increase due to two factors: 1. A reduction in the amount of soil organic N mineralised due to the continued decline of natural capital (soil organic carbon and total nitrogen) that occurs under cropping; and 2. An increased crop N demand due to higher yield potentials resulting from optimising other components of the cropping system. The amount of biological N fixation by pulse crops (chickpea/mungbean) is related to the crop yield and biomass and the availability of soil mineral N from mineralisation or carry-over of residual fertiliser. Where deep phosphorus (P) and potassium (K) application increases chickpea biomass (and grain yield), there is generally more N fixed. While some of this is re-exported in grain, the greater residue return means more N is carried forward to the next crop. Growers have a selection of fertiliser N management practices that have differing strengths and weaknesses – it is not a one-size-fits-all model for CQ (or northern region) farming systems. The 4R framework allows choice of rate, source, time and place for any nutrient applied to be implemented suiting each growers’ preferences, with on-going research addressing several themes in regional Qld.

Take home messages The nitrogen (N) fertiliser demand for cereal cropping systems can increase due to two factors: 1. A reduction in the amount of soil organic N mineralised due to the continued decline of natural capital (soil organic carbon and total nitrogen) that occurs under cropping; and 2. An increased crop N demand due to higher yield potentials resulting from optimising other components of the cropping system. The amount of biological N fixation by pulse crops (chickpea/mungbean) is related to the crop yield and biomass and the availability of soil mineral N from mineralisation or carry-over of residual fertiliser. Where deep phosphorus (P) and potassium (K) application increases chickpea biomass (and grain yield), there is generally more N fixed. While some of this is re-exported in grain, the greater residue return means more N is carried forward to the next crop. Growers have a selection of fertiliser N management practices that have differing strengths and weaknesses – it is not a one-size-fits-all model for CQ (or northern region) farming systems. The 4R framework allows choice of rate, source, time and place for any nutrient applied to be implemented suiting each growers’ preferences, with on-going research addressing several themes in regional Qld.

Take home message • Nitrogen derived from atmosphere (Ndfa) in mungbean crops is strongly influenced by the amount of mineral soil nitrates that are available at planting. There is an almost linear decline in N2 fixation as soil nitrates increase in the top 60cm of the profile. • Mungbean and chickpea crops can access and utilise soil nitrate N in the top 60cm as efficiently as cereal crops. This raises implications for nitrate N supply in crops following these pulse crops. • Mungbeans planted in long fallow situations will create a soil nitrate N deficit as N2 fixation rates cannot replace the amount of soil nitrate being exported in grain. Circumstantial evidence suggests that chickpeas may be similar.

Take home messages The nitrogen (N) fertiliser demand for cereal cropping systems can increase due to two factors: 1. A reduction in the amount of soil organic N mineralised due to the continued decline of natural capital (soil organic carbon and total nitrogen) that occurs under cropping; and 2. An increased crop N demand due to higher yield potentials resulting from optimising other components of the cropping system. The amount of biological N fixation by pulse crops (chickpea/mungbean) is related to the crop yield and biomass and the availability of soil mineral N from mineralisation or carry-over of residual fertiliser. Where deep phosphorus (P) and potassium (K) application increases chickpea biomass (and grain yield), there is generally more N fixed. While some of this is re-exported in grain, the greater residue return means more N is carried forward to the next crop. Growers have a selection of fertiliser N management practices that have differing strengths and weaknesses – it is not a one-size-fits-all model for CQ (or northern region) farming systems. The 4R framework allows choice of rate, source, time and place for any nutrient applied to be implemented suiting each growers’ preferences, with on-going research addressing several themes in regional Qld.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

Early sown sorghum is a viable alternative for the Liverpool Plains of NSW. It is currently unknown if the longer vegetative period created by sowing into sub-optimal soil temperatures could affect water productivity. Water use was measured on an early (Agitator) and a late (MR Buster) maturing hybrid, sown in early and late spring and summer in 2018 and 2019 at 30, 60 (standard practice) and 120 thousand plants/ha. Crops sown very early into cooler soil conditions had lower water use than those sown at early and normal sowing times. There was a significant impact of time of sowing on grain yield, which was seasonally dependent. Water productivity for MR Buster was higher when grown at 30,000 plants/ha compared to the standard density and higher density. For Agitator, earlier sowing reduced water productivity. The potential of early sowing to increase yield and water productivity of sorghum needs assessment under additional seasons and environmental conditions.

Early sown sorghum is a viable alternative for the Liverpool Plains of NSW. It is currently unknown if the longer vegetative period created by sowing into sub-optimal soil temperatures could affect water productivity. Water use was measured on an early (Agitator) and a late (MR Buster) maturing hybrid, sown in early and late spring and summer in 2018 and 2019 at 30, 60 (standard practice) and 120 thousand plants/ha. Crops sown very early into cooler soil conditions had lower water use than those sown at early and normal sowing times. There was a significant impact of time of sowing on grain yield, which was seasonally dependent. Water productivity for MR Buster was higher when grown at 30,000 plants/ha compared to the standard density and higher density. For Agitator, earlier sowing reduced water productivity. The potential of early sowing to increase yield and water productivity of sorghum needs assessment under additional seasons and environmental conditions.

Researching the management (M) of genotypes (G) in agronomic experimentation is essential to help farmers maximise grain yield, though the approach is complicated by interactions emerging from changing environmental (E) factors across sites and seasons. Available statistical methods for modelling the G×E interaction are limited as they do not provide a functional understanding of how environmental factors influence the G×E interaction, nor assess how different management practices (M) influence the G×E interaction. A predictive linear mixed model is proposed that incorporates site/season-specific environmental covariates into a standard G×E interaction framework. The model is extended to include continuously varying agronomic management practices whilst allowing for non-linear trait responses and complex variance structures. The methodology was applied to a multi-environment data set associated with GRDC’s optimising sorghum agronomy program. The analysis identified key environmental drivers and management strategies that explained the G×E×M interaction, enhancing the biological understanding of the analysis results and allowing for the development of more robust recommendations for agronomic practices.

The efficiency of soil water accumulation during fallow periods, and the availability of that soil water for use by crops are key drivers of northern farming system productivity and profitability. In 2015 seven farming systems experiments were established from central Queensland to central New South Wales to answer the question; Can system performance be improved by modifying farming systems in the northern grains region? To assess this soil water dynamics were monitored under different farming systems, along with soil nitrogen, pathogens, crop biomass, grain yield and variable costs, as measures of system performance. Analysis of soil water accumulation during the fallows and its subsequent use by sorghum, wheat and chickpea crops, showed a cost to all crops for converting biomass to grain yield. This cost was least for chickpea (50 mm), followed by wheat (100 mm) and highest for sorghum (150 mm), and should be deducted from crop water use to calculate water-use-efficiency (WUE). The WUE was lowest for pulse crops (10 kg/mm), but sorghum and wheat returned the same WUE (17 kg/mm). Northern growers typically store plant-available-water (PAW) in the fallow as a buffer against variable quantity and timing of in-crop rainfall. Crops produced a better than average WUE when planted with at least 60 mm PAW in a high in-crop rainfall season, or 120 mm of PAW with low in-crop rainfall.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The efficiency of soil water accumulation during fallow periods, and the availability of that soil water for use by crops are key drivers of northern farming system productivity and profitability. In 2015 seven farming systems experiments were established from central Queensland to central New South Wales to answer the question; Can system performance be improved by modifying farming systems in the northern grains region? To assess this soil water dynamics were monitored under different farming systems, along with soil nitrogen, pathogens, crop biomass, grain yield and variable costs, as measures of system performance. Analysis of soil water accumulation during the fallows and its subsequent use by sorghum, wheat and chickpea crops, showed a cost to all crops for converting biomass to grain yield. This cost was least for chickpea (50 mm), followed by wheat (100 mm) and highest for sorghum (150 mm), and should be deducted from crop water use to calculate water-use-efficiency (WUE). The WUE was lowest for pulse crops (10 kg/mm), but sorghum and wheat returned the same WUE (17 kg/mm). Northern growers typically store plant-available-water (PAW) in the fallow as a buffer against variable quantity and timing of in-crop rainfall. Crops produced a better than average WUE when planted with at least 60 mm PAW in a high in-crop rainfall season, or 120 mm of PAW with low in-crop rainfall.

Researching the management (M) of genotypes (G) in agronomic experimentation is essential to help farmers maximise grain yield, though the approach is complicated by interactions emerging from changing environmental (E) factors across sites and seasons. Available statistical methods for modelling the G×E interaction are limited as they do not provide a functional understanding of how environmental factors influence the G×E interaction, nor assess how different management practices (M) influence the G×E interaction. A predictive linear mixed model is proposed that incorporates site/season-specific environmental covariates into a standard G×E interaction framework. The model is extended to include continuously varying agronomic management practices whilst allowing for non-linear trait responses and complex variance structures. The methodology was applied to a multi-environment data set associated with GRDC’s optimising sorghum agronomy program. The analysis identified key environmental drivers and management strategies that explained the G×E×M interaction, enhancing the biological understanding of the analysis results and allowing for the development of more robust recommendations for agronomic practices.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Researching the management (M) of genotypes (G) in agronomic experimentation is essential to help farmers maximise grain yield, though the approach is complicated by interactions emerging from changing environmental (E) factors across sites and seasons. Available statistical methods for modelling the G×E interaction are limited as they do not provide a functional understanding of how environmental factors influence the G×E interaction, nor assess how different management practices (M) influence the G×E interaction. A predictive linear mixed model is proposed that incorporates site/season-specific environmental covariates into a standard G×E interaction framework. The model is extended to include continuously varying agronomic management practices whilst allowing for non-linear trait responses and complex variance structures. The methodology was applied to a multi-environment data set associated with GRDC’s optimising sorghum agronomy program. The analysis identified key environmental drivers and management strategies that explained the G×E×M interaction, enhancing the biological understanding of the analysis results and allowing for the development of more robust recommendations for agronomic practices.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The efficiency of soil water accumulation during fallow periods, and the availability of that soil water for use by crops are key drivers of northern farming system productivity and profitability. In 2015 seven farming systems experiments were established from central Queensland to central New South Wales to answer the question; Can system performance be improved by modifying farming systems in the northern grains region? To assess this soil water dynamics were monitored under different farming systems, along with soil nitrogen, pathogens, crop biomass, grain yield and variable costs, as measures of system performance. Analysis of soil water accumulation during the fallows and its subsequent use by sorghum, wheat and chickpea crops, showed a cost to all crops for converting biomass to grain yield. This cost was least for chickpea (50 mm), followed by wheat (100 mm) and highest for sorghum (150 mm), and should be deducted from crop water use to calculate water-use-efficiency (WUE). The WUE was lowest for pulse crops (10 kg/mm), but sorghum and wheat returned the same WUE (17 kg/mm). Northern growers typically store plant-available-water (PAW) in the fallow as a buffer against variable quantity and timing of in-crop rainfall. Crops produced a better than average WUE when planted with at least 60 mm PAW in a high in-crop rainfall season, or 120 mm of PAW with low in-crop rainfall.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

Winter sown sorghum reduces the impact of heat and water stresses around flowering and increases cropping intensity, though, achieving uniform plant establishment remains challenging. Sowing sorghum in winter will require crops to uniformly germinate and emerge in soils which are cooler than the recommended >16ºC minimum daily temperature, during the driest time of the year. Prolonged emergence periods and reduced total emergence can decrease canopy uniformity with negative impacts on yield, crop management and cropping system intensity. Acceptable establishment percentages (>80%) were achieved for some site by seedlot combinations, though large differences in establishment rate between seedlots were observed. The differences in seedlot emerge rate were related to final establishment. This calls for seed vigour testing, novel seed production technologies, management of seedbed hydrothermal conditions and breeding programs for cold tolerance.

The efficiency of soil water accumulation during fallow periods, and the availability of that soil water for use by crops are key drivers of northern farming system productivity and profitability. In 2015 seven farming systems experiments were established from central Queensland to central New South Wales to answer the question; Can system performance be improved by modifying farming systems in the northern grains region? To assess this soil water dynamics were monitored under different farming systems, along with soil nitrogen, pathogens, crop biomass, grain yield and variable costs, as measures of system performance. Analysis of soil water accumulation during the fallows and its subsequent use by sorghum, wheat and chickpea crops, showed a cost to all crops for converting biomass to grain yield. This cost was least for chickpea (50 mm), followed by wheat (100 mm) and highest for sorghum (150 mm), and should be deducted from crop water use to calculate water-use-efficiency (WUE). The WUE was lowest for pulse crops (10 kg/mm), but sorghum and wheat returned the same WUE (17 kg/mm). Northern growers typically store plant-available-water (PAW) in the fallow as a buffer against variable quantity and timing of in-crop rainfall. Crops produced a better than average WUE when planted with at least 60 mm PAW in a high in-crop rainfall season, or 120 mm of PAW with low in-crop rainfall.

The efficiency of soil water accumulation during fallow periods, and the availability of that soil water for use by crops are key drivers of northern farming system productivity and profitability. In 2015 seven farming systems experiments were established from central Queensland to central New South Wales to answer the question; Can system performance be improved by modifying farming systems in the northern grains region? To assess this soil water dynamics were monitored under different farming systems, along with soil nitrogen, pathogens, crop biomass, grain yield and variable costs, as measures of system performance. Analysis of soil water accumulation during the fallows and its subsequent use by sorghum, wheat and chickpea crops, showed a cost to all crops for converting biomass to grain yield. This cost was least for chickpea (50 mm), followed by wheat (100 mm) and highest for sorghum (150 mm), and should be deducted from crop water use to calculate water-use-efficiency (WUE). The WUE was lowest for pulse crops (10 kg/mm), but sorghum and wheat returned the same WUE (17 kg/mm). Northern growers typically store plant-available-water (PAW) in the fallow as a buffer against variable quantity and timing of in-crop rainfall. Crops produced a better than average WUE when planted with at least 60 mm PAW in a high in-crop rainfall season, or 120 mm of PAW with low in-crop rainfall.

The idea that “Yield is King” fails to acknowledge that what matters most to farmers is farm profits and risk, rather than yield. This is because decisions made in one season will affect options and crop performance over the next few years. Therefore, quantifying the longer-term impacts of innovation adoption is important. We used the Agricultural Production Simulation model (APSIM) to simulate and investigate the implications of adopting rain-fed winter sown sorghum in the Australian northern grains region. Results indicate that within a crop rotation early-planted sorghum will tend to decrease median sorghum crop yields but increase the following winter crop yields. This appears to have a marginal economic effect in Breeza and Dalby but encouraging results in Emerald. The inclusion of chickpea within the rotation increased returns in the best seasons with little change to downside risks in poor seasons.

Early sown sorghum is a viable alternative for the Liverpool Plains of NSW. It is currently unknown if the longer vegetative period created by sowing into sub-optimal soil temperatures could affect water productivity. Water use was measured on an early (Agitator) and a late (MR Buster) maturing hybrid, sown in early and late spring and summer in 2018 and 2019 at 30, 60 (standard practice) and 120 thousand plants/ha. Crops sown very early into cooler soil conditions had lower water use than those sown at early and normal sowing times. There was a significant impact of time of sowing on grain yield, which was seasonally dependent. Water productivity for MR Buster was higher when grown at 30,000 plants/ha compared to the standard density and higher density. For Agitator, earlier sowing reduced water productivity. The potential of early sowing to increase yield and water productivity of sorghum needs assessment under additional seasons and environmental conditions.

History shows that transformational changes in agriculture are rarely associated with the adoption of single innovations. It has been argued that transformative changes in agriculture have usually resulted from the incremental adoption of complementary technologies, and result in ongoing increases in yield from improvements from breeding and agronomy – though gains in productivity remain piece meal, insufficient and primarily confused with adoption processes. Here we propose that there is a role and need to design research that aims to be more transformative, likely to have larger than the ongoing or incremental gains, and that can be achieved in shorter periods of time. This argument is discussed by summarising the results of a four-year cross-agency research program conducted across Eastern Australia that tested crop designs of winter sown sorghum (WSS). The innovation is a systems adaptation with the potential to produce gains in productivity and farmer profits beyond what is the incremental or ongoing yield gain – though impact will still be dependent on adoption rates.

Grain sorghum yield is often reduced by heat and water stress during critical growth stages around anthesis when planted in the traditional sowing window. Sorghum sown during late winter or early spring can flower before these stresses develop, though reduced plant establishments due to sub optimal soil temperatures and the likelihood of frost damage need to be managed. Two years of experiments at Mungindi, Moree and the Liverpool Plains in Northern NSW compared sowing time effect on plant establishment, date of anthesis and grain yield. Sorghum can be established in sub-optimal temperatures (<16°C) if seedbed moisture is available but losses of 10-30% need to be factored into sowing rates. The overlap between flowering and heat stress was minimised by ‘winter’ or early spring sowing. Grain yield was maintained or improved by planting earlier compared to traditional sowing times.