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Increased yield stability of field-grown winter barley (Hordeum vulgare L.) varietal mixtures through ecological processes.

Creissen HE, Jorgensen TH, Brown JK - Crop Prot. (2016)

Bottom Line: There was compensation through competitive release because the most competitive variety overyielded in mixtures thereby compensating for less competitive varieties.Facilitation was also identified as an important ecological process within mixtures by reducing lodging.They may confer enhanced resilience to environmental stresses and thus be a desirable component of future cropping systems for sustainable arable farming.

View Article: PubMed Central - PubMed

Affiliation: Crop Genetics Department, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK; School of Biological Sciences, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.

ABSTRACT

Crop variety mixtures have the potential to increase yield stability in highly variable and unpredictable environments, yet knowledge of the specific mechanisms underlying enhanced yield stability has been limited. Ecological processes in genetically diverse crops were investigated by conducting field trials with winter barley varieties (Hordeum vulgare), grown as monocultures or as three-way mixtures in fungicide treated and untreated plots at three sites. Mixtures achieved yields comparable to the best performing monocultures whilst enhancing yield stability despite being subject to multiple predicted and unpredicted abiotic and biotic stresses including brown rust (Puccinia hordei) and lodging. There was compensation through competitive release because the most competitive variety overyielded in mixtures thereby compensating for less competitive varieties. Facilitation was also identified as an important ecological process within mixtures by reducing lodging. This study indicates that crop varietal mixtures have the capacity to stabilise productivity even when environmental conditions and stresses are not predicted in advance. Varietal mixtures provide a means of increasing crop genetic diversity without the need for extensive breeding efforts. They may confer enhanced resilience to environmental stresses and thus be a desirable component of future cropping systems for sustainable arable farming.

No MeSH data available.


Related in: MedlinePlus

Relative yields of four winter barley varieties grown in mixtures in fungicide treated or untreated plots in a field trial conducted over three different sites. Relative yield was calculated by multiplying proportions contributed by each variety to the overall mixture plot yield by the total mixture plot yield (g), and dividing by the average plot yield of that variety in monoculture). Error bar shows Least Significant Difference at the 5% level. N = 24 per monoculture.
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fig3: Relative yields of four winter barley varieties grown in mixtures in fungicide treated or untreated plots in a field trial conducted over three different sites. Relative yield was calculated by multiplying proportions contributed by each variety to the overall mixture plot yield by the total mixture plot yield (g), and dividing by the average plot yield of that variety in monoculture). Error bar shows Least Significant Difference at the 5% level. N = 24 per monoculture.

Mentions: Mean yields of mixtures and monocultures were similar across the entire experiment (Table A2, F3,10 = 2.23, P = 0.1) but mixture yields were more stable than monoculture yields as shown by lower values of W2 in the mixtures compared to the mean of their component varieties grown as monocultures (Fig. 1). Mixture yields were stable, despite the presence of a variety with highly variable yields, Winsome, in both mixtures (Fig. 1, Fig. 2). Mixture performance of each variety was altered by the site and fungicide treatment, shown by changes in relative yield (Fig. 3). Mixture B was more stable than any monoculture but less stable than Mixture A (Fig. 1) indicating that relatively minor modifications to mixture composition by the substitution of a single variety in a three-way mixture can change the outcome of the ecological processes and the resulting agronomic performance of the mixture. Element generally performed better in mixture indicating that inter-plant competition was greater within monocultures (Fig. 3). The success of Element in mixtures appeared to be partly due to plasticity in certain yield components, because the variety tended to have greater mean ear mass in mixture (Table A3a, F3,9 = 3.6, P = 0.01). Plasticity in mean ear mass data was dependent on cultivation (mixture/monoculture) but not site (Table A3a, F1,9 = 0.42, P = 0.5). Cassata's low competitive ability in mixtures led to a reduction in yield and yield components including mean mass per ear (Fig. 3, Table A3a, F3,9 = 3.6, P = 0.01). Element overyielded in mixture and thus compensated for under-yielding varieties, resulting in high and stable mixture yields across the entire experiment (Fig. 2, Fig. 3).


Increased yield stability of field-grown winter barley (Hordeum vulgare L.) varietal mixtures through ecological processes.

Creissen HE, Jorgensen TH, Brown JK - Crop Prot. (2016)

Relative yields of four winter barley varieties grown in mixtures in fungicide treated or untreated plots in a field trial conducted over three different sites. Relative yield was calculated by multiplying proportions contributed by each variety to the overall mixture plot yield by the total mixture plot yield (g), and dividing by the average plot yield of that variety in monoculture). Error bar shows Least Significant Difference at the 5% level. N = 24 per monoculture.
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4862440&req=5

fig3: Relative yields of four winter barley varieties grown in mixtures in fungicide treated or untreated plots in a field trial conducted over three different sites. Relative yield was calculated by multiplying proportions contributed by each variety to the overall mixture plot yield by the total mixture plot yield (g), and dividing by the average plot yield of that variety in monoculture). Error bar shows Least Significant Difference at the 5% level. N = 24 per monoculture.
Mentions: Mean yields of mixtures and monocultures were similar across the entire experiment (Table A2, F3,10 = 2.23, P = 0.1) but mixture yields were more stable than monoculture yields as shown by lower values of W2 in the mixtures compared to the mean of their component varieties grown as monocultures (Fig. 1). Mixture yields were stable, despite the presence of a variety with highly variable yields, Winsome, in both mixtures (Fig. 1, Fig. 2). Mixture performance of each variety was altered by the site and fungicide treatment, shown by changes in relative yield (Fig. 3). Mixture B was more stable than any monoculture but less stable than Mixture A (Fig. 1) indicating that relatively minor modifications to mixture composition by the substitution of a single variety in a three-way mixture can change the outcome of the ecological processes and the resulting agronomic performance of the mixture. Element generally performed better in mixture indicating that inter-plant competition was greater within monocultures (Fig. 3). The success of Element in mixtures appeared to be partly due to plasticity in certain yield components, because the variety tended to have greater mean ear mass in mixture (Table A3a, F3,9 = 3.6, P = 0.01). Plasticity in mean ear mass data was dependent on cultivation (mixture/monoculture) but not site (Table A3a, F1,9 = 0.42, P = 0.5). Cassata's low competitive ability in mixtures led to a reduction in yield and yield components including mean mass per ear (Fig. 3, Table A3a, F3,9 = 3.6, P = 0.01). Element overyielded in mixture and thus compensated for under-yielding varieties, resulting in high and stable mixture yields across the entire experiment (Fig. 2, Fig. 3).

Bottom Line: There was compensation through competitive release because the most competitive variety overyielded in mixtures thereby compensating for less competitive varieties.Facilitation was also identified as an important ecological process within mixtures by reducing lodging.They may confer enhanced resilience to environmental stresses and thus be a desirable component of future cropping systems for sustainable arable farming.

View Article: PubMed Central - PubMed

Affiliation: Crop Genetics Department, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK; School of Biological Sciences, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.

ABSTRACT

Crop variety mixtures have the potential to increase yield stability in highly variable and unpredictable environments, yet knowledge of the specific mechanisms underlying enhanced yield stability has been limited. Ecological processes in genetically diverse crops were investigated by conducting field trials with winter barley varieties (Hordeum vulgare), grown as monocultures or as three-way mixtures in fungicide treated and untreated plots at three sites. Mixtures achieved yields comparable to the best performing monocultures whilst enhancing yield stability despite being subject to multiple predicted and unpredicted abiotic and biotic stresses including brown rust (Puccinia hordei) and lodging. There was compensation through competitive release because the most competitive variety overyielded in mixtures thereby compensating for less competitive varieties. Facilitation was also identified as an important ecological process within mixtures by reducing lodging. This study indicates that crop varietal mixtures have the capacity to stabilise productivity even when environmental conditions and stresses are not predicted in advance. Varietal mixtures provide a means of increasing crop genetic diversity without the need for extensive breeding efforts. They may confer enhanced resilience to environmental stresses and thus be a desirable component of future cropping systems for sustainable arable farming.

No MeSH data available.


Related in: MedlinePlus