Halbwirth H, Waldner I, Miosic S, Ibanez M, Costa G, Stich K. 2009. Measuring Flavonoid Enzyme Activities in Tissues of Fruit SpeciesMeasuring Flavonoid Enzyme Activities in Tissues of Fruit Species. J Agric Food Chem. 2009 Jun 10;57(11):4983-7. doi: 10.1021/jf900121z.
ABSTRACT
Flavonoids are important secondary metabolites, which are ubiquitously present in plant-derived food. Since flavonoids may show beneficial effects on human health, there is increasing interest in the availability of plants with a tailor-made flavonoid spectrum. Determination of flavonoid enzyme activities and investigations into their substrate specificity are an important precondition for both classical and molecular approaches. We tested two different protocols for enzyme preparation from eight fruit species. In many cases, a protocol adapted for polyphenol-rich tissues was superior. Using a suitable protocol for investigations of kiwi fruits, we show that flavanone 3-hydroxylase is absent in the green-fleshed cultivar Hayward. As flavonoid enzyme activities could be detected in harvested kiwi fruits over a storage period of five months, postharvest modification of the flavonoid spectrum has to be expected.
Hoeberichts F, Povero G, Ibanez M, Strijker A, Pezzolato D, Mills R, Piaggesi A, 2017. Next Generation Sequencing to characterize the breaking of bud dormancy using a natural biostimulant in kiwifruit (Actinidia deliciosa). Scientia Horticulturae Volume 225, 18 November 2017, Pages 252-263. doi:10.1016/j.scienta.2017.07.011
ABSTRACT
Dormancy occurs in many woody perennials and fruit trees, and is characterised mainly by the temporal absence of growth. This strategy has an ecological role in ensuring plant survival under non-permissive growing conditions. In kiwifruit (Actinidia deliciosa), buds must be exposed to a certain amount of chilling to complete dormancy and achieve optimal bud break and flowering in spring. However, in warmer geographical areas bud break can be limited by insufficient winter chilling, leading to less and uneven flowering and lower productivity. Several bud break-enhancing compounds have been shown to be effective in kiwifruit, overcoming the negative effects of poor winter chilling. However, their mode of action is still largely unknown. In this work, using a molecular approach based on Next Generation Sequencing, we characterised dormancy and its breaking after the application of the biostimulant Erger®. Samples were collected at different time-points and in distinct geographical areas, namely Italy and New Zealand. Our results indicated that the effect of Erger® depends on the moment of application. Furthermore, molecular mechanisms that characterise a biostimulant treatment for bud break, irrespective of the region and seasonality, were identified. This characterisation opens new perspectives to improve bud break-enhancing compound formulations and identify their best moment of application.
Ibáñez Revert M., Hoeberichts F., Kay C., Black M. 2017. El análisis genético como herramienta para superar los problemas relacionados con la latencia. Fruticultura nº 58
ABSTRACT
The genetic analysis as a tool to overcome problems related to dormancy. A good flowering is the key for the profitability in woody tree production. In temperate climates, the use of the so-called dormancy breakers promotes earlier and more uniform bud break and flowering. However, the results of this type of treatment can be unpredictable.
NSure and Zespri have developed a test for kiwi (Hayward and Gold3) that determines the physiological state of plants in relation to optimal application of the dormancy breakers. The development of the test is the result of several trials performed in Italy and New Zealand. Using the Next Generation Sequencing technology, the genetic profile during dormancy release was characterized and related to the response of the plants to the different results of the treatments.
The development of the test for kiwi allows to predict the potential of a tool whose use can be extended to all tree crops that share the same problems.
