South Africa Wine Research Projects

2. VITICULTURE RESEARCH COMPLETED PROJECT

EFFECT OF MECHANICAL PRUNING ON GRAPEVINE TRUNK DISEASES

P04000236 Prof Francois Halleen, ARC Infruitec-Nietvoorbij, Stellenbosch Project was co-funded by the ARC Infruitec-Nietvoorbij Project completed: 2023

AIM AND INDUSTRY RELEVANCE: This study aimed to investigate the effect of mechanical pruning (MP) on the presence of grape vine trunk disease pathogens in contrast to conventional hand pruning (HP). Selected vineyards were hand- or mechanically pruned during four consecutive dormant seasons. To assess pathogen occurrence and severity, fungal isolations were done on pruning wounds and older three to four weeks post pruning. Overall, HP vines exhibited a higher occurrence and severities of dieback and canker pathogens compared to MP vines, with the differences primarily stemming from larger cuts made close to the cordon in HP vines. Therefore, do not make large cuts close to the cordon. In addition, MP vines featured longer canes, providing increased opportunities for the vine to counterpoise dying shoots. The researchers concluded that mechanical pruning in a single (MP1) or double cordon (MP3) and using hand pruning using shears and a mechanical saw that mimicked a mechanical pruning method (MP3) appears to be a viable option of pruning resulting in less than expected trunk pathogen infections.

SOUTH AFRICA WINE RESEARCH 2024

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