Do Chemical Treatments that Influence Inflorescence Necrosis Severity affect Grape Flower Cluster NH4+?
Year: 1995
Type: article
Abstract: A fruit-set disorder of grape, called Inflorescence Necrosis (IN), causes death of flower cluster tissue near bloom. Various chemical treatments have been reported to increase IN severity. Separate studies show that high flower cluster NH4+ is related to naturally occurring IN. We designed a field trial to determine if treatments thought to influence IN severity also affect flower cluster NH4+. One week before first bloom, flower clusters were dipped in solutions of either methionine sulfoximine (MSO, an inhibitor of NH4+ assimilation), α-keto glutarate, (NH4)2HPO4, KNO3, NAA, GA, or an emulsion solution reported to increase transpiration. Also, ethephon was sprayed on whole vines 1 week before first bloom. Flower clusters were collected 5 days after treatment. MSO increased tissue [NH4+] by almost 2-fold over that of controls. NAA and GA reduced [NH4+] a small amount, possibly due to their slightly higher fresh weights. Other dip treatments did not affect [NH4+]. Despite high [NH4+] in MSO treated clusters, there were no visual differences in IN between treatments. Ethephon increased cluster [NH4+] 20% over that of controls, but caused more severe IN. These data show that flower cluster [NH4+] is not always coupled with IN symptoms.
Source: HortScience
Authors: Glen L. Creasy, Patrick J. Breen
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: hybrid
Estimated APC paid: $3,000
OpenAlex ID: W2512633837