Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators
Uniform grape maturity can be sought by producers to minimise underripe and/or overripe proportions of fruit and limit any undesirable effects on wine quality. Considering that grape heterogeneity is a multifaceted phenomenon, a composite index summarising overall grape heterogeneity was developed t...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-03-01
|
| Series: | Plants |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2223-7747/12/7/1442 |
| _version_ | 1797607224835571712 |
|---|---|
| author | Claire E. J. Armstrong Pietro Previtali Paul K. Boss Vinay Pagay Robert G. V. Bramley David W. Jeffery |
| author_facet | Claire E. J. Armstrong Pietro Previtali Paul K. Boss Vinay Pagay Robert G. V. Bramley David W. Jeffery |
| author_sort | Claire E. J. Armstrong |
| collection | DOAJ |
| description | Uniform grape maturity can be sought by producers to minimise underripe and/or overripe proportions of fruit and limit any undesirable effects on wine quality. Considering that grape heterogeneity is a multifaceted phenomenon, a composite index summarising overall grape heterogeneity was developed to benefit vineyard management and harvest date decisions. A grape heterogeneity index (GHI) was constructed by aggregating the sum of absolute residuals multiplied by the range of values from measurements of total soluble solids, pH, fresh weight, total tannins, absorbance at 520 nm (red colour), 3-isobutyl-2-methoxypyrazine, and malic acid. Management of grape heterogeneity was also studied, using Cabernet Sauvignon grapes grown under four viticultural regimes (normal/low crop load, full/deficit irrigation) during the 2019/2020 and 2020/2021 seasons. Comparisons of GHI scores showed grape variability decreased throughout ripening in both vintages, then significantly increased at the harvest time point in 2020, but plateaued on sample dates nearing the harvest date in 2021. Irrigation and crop load had no effect on grape heterogeneity by the time of harvest in both vintages. Larger vine yield, leaf area index, and pruning weight significantly increased GHI score early in ripening, but no significant relationship was found at the time of harvest. Differences in the Ravaz index, normalised difference vegetation index, and soil electrical conductivity did not significantly change the GHI score. |
| first_indexed | 2024-03-11T05:28:12Z |
| format | Article |
| id | doaj.art-d7d06f17d53e4c5aa191e25c068917fe |
| institution | Directory Open Access Journal |
| issn | 2223-7747 |
| language | English |
| last_indexed | 2024-03-11T05:28:12Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Plants |
| spelling | doaj.art-d7d06f17d53e4c5aa191e25c068917fe2023-11-17T17:22:36ZengMDPI AGPlants2223-77472023-03-01127144210.3390/plants12071442Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple IndicatorsClaire E. J. Armstrong0Pietro Previtali1Paul K. Boss2Vinay Pagay3Robert G. V. Bramley4David W. Jeffery5Australian Research Council Training Centre for Innovative Wine Production, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, AustraliaAustralian Research Council Training Centre for Innovative Wine Production, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, AustraliaAustralian Research Council Training Centre for Innovative Wine Production, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, AustraliaAustralian Research Council Training Centre for Innovative Wine Production, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, AustraliaCSIRO Agriculture and Food, Locked Bag 2, Glen Osmond, SA 5064, AustraliaAustralian Research Council Training Centre for Innovative Wine Production, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, AustraliaUniform grape maturity can be sought by producers to minimise underripe and/or overripe proportions of fruit and limit any undesirable effects on wine quality. Considering that grape heterogeneity is a multifaceted phenomenon, a composite index summarising overall grape heterogeneity was developed to benefit vineyard management and harvest date decisions. A grape heterogeneity index (GHI) was constructed by aggregating the sum of absolute residuals multiplied by the range of values from measurements of total soluble solids, pH, fresh weight, total tannins, absorbance at 520 nm (red colour), 3-isobutyl-2-methoxypyrazine, and malic acid. Management of grape heterogeneity was also studied, using Cabernet Sauvignon grapes grown under four viticultural regimes (normal/low crop load, full/deficit irrigation) during the 2019/2020 and 2020/2021 seasons. Comparisons of GHI scores showed grape variability decreased throughout ripening in both vintages, then significantly increased at the harvest time point in 2020, but plateaued on sample dates nearing the harvest date in 2021. Irrigation and crop load had no effect on grape heterogeneity by the time of harvest in both vintages. Larger vine yield, leaf area index, and pruning weight significantly increased GHI score early in ripening, but no significant relationship was found at the time of harvest. Differences in the Ravaz index, normalised difference vegetation index, and soil electrical conductivity did not significantly change the GHI score.https://www.mdpi.com/2223-7747/12/7/1442Cabernet Sauvignoncomposite indicatorgrape variabilitygrape maturityvineyard managementviticulture |
| spellingShingle | Claire E. J. Armstrong Pietro Previtali Paul K. Boss Vinay Pagay Robert G. V. Bramley David W. Jeffery Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators Plants Cabernet Sauvignon composite indicator grape variability grape maturity vineyard management viticulture |
| title | Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators |
| title_full | Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators |
| title_fullStr | Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators |
| title_full_unstemmed | Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators |
| title_short | Grape Heterogeneity Index: Assessment of Overall Grape Heterogeneity Using an Aggregation of Multiple Indicators |
| title_sort | grape heterogeneity index assessment of overall grape heterogeneity using an aggregation of multiple indicators |
| topic | Cabernet Sauvignon composite indicator grape variability grape maturity vineyard management viticulture |
| url | https://www.mdpi.com/2223-7747/12/7/1442 |
| work_keys_str_mv | AT claireejarmstrong grapeheterogeneityindexassessmentofoverallgrapeheterogeneityusinganaggregationofmultipleindicators AT pietroprevitali grapeheterogeneityindexassessmentofoverallgrapeheterogeneityusinganaggregationofmultipleindicators AT paulkboss grapeheterogeneityindexassessmentofoverallgrapeheterogeneityusinganaggregationofmultipleindicators AT vinaypagay grapeheterogeneityindexassessmentofoverallgrapeheterogeneityusinganaggregationofmultipleindicators AT robertgvbramley grapeheterogeneityindexassessmentofoverallgrapeheterogeneityusinganaggregationofmultipleindicators AT davidwjeffery grapeheterogeneityindexassessmentofoverallgrapeheterogeneityusinganaggregationofmultipleindicators |