Abstract In 1994, heavily flowering ‘York’ apple trees (Malus Xdomestica Borkh.) selected for 80% or more of spurs flowering were hand thinned to a crop density (CD) of approximately 7 fruit/cm2 trunk cross-sectional area (FCSA) at bloom, petal fall, or up to 61 days after bloom. This thinning did not result in an adequate return bloom even for a partial crop in 1995. Heavily flowering ‘Golden Delicious’/M.26 trees were treated similarly in 1994 and responded with more flowering in 1995 than ‘York’/M.26 trees. In 1995, a different group of heavily flowering ‘York’/M.26 trees were hand thinned to a CD of 3 to 5 FCSA at bloom and at 7 day intervals up to 35 days AFB. Thinning at bloom or 7 days after full bloom (4.5 mmfruit diameter) resulted in much greater return bloom in 1996 than any other thinning. In 1995, ‘Golden Delicious’/M.26 trees were treated similarly to ‘York’/M.26 and responded similarly in 1996 with the greatest return bloom resulting from bloom thinning with somewhat less return bloom from thinning 7 or 14 days after full bloom and dramatically reduced return bloom.
{"title":"Effects of Thinning Time on Yield, Fruit Size, and Return Bloom of ‘York’ and ‘Golden Delicious’ Apple Trees","authors":"R. Byers, D. H. Carbaugh","doi":"10.1300/J072v03n01_05","DOIUrl":"https://doi.org/10.1300/J072v03n01_05","url":null,"abstract":"Abstract In 1994, heavily flowering ‘York’ apple trees (Malus Xdomestica Borkh.) selected for 80% or more of spurs flowering were hand thinned to a crop density (CD) of approximately 7 fruit/cm2 trunk cross-sectional area (FCSA) at bloom, petal fall, or up to 61 days after bloom. This thinning did not result in an adequate return bloom even for a partial crop in 1995. Heavily flowering ‘Golden Delicious’/M.26 trees were treated similarly in 1994 and responded with more flowering in 1995 than ‘York’/M.26 trees. In 1995, a different group of heavily flowering ‘York’/M.26 trees were hand thinned to a CD of 3 to 5 FCSA at bloom and at 7 day intervals up to 35 days AFB. Thinning at bloom or 7 days after full bloom (4.5 mmfruit diameter) resulted in much greater return bloom in 1996 than any other thinning. In 1995, ‘Golden Delicious’/M.26 trees were treated similarly to ‘York’/M.26 and responded similarly in 1996 with the greatest return bloom resulting from bloom thinning with somewhat less return bloom from thinning 7 or 14 days after full bloom and dramatically reduced return bloom.","PeriodicalId":117688,"journal":{"name":"Journal of Tree Fruit Production","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114689100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Stayman/M.27 (Malus Xdomestica Borkh.) placed in the dark for 60 hours at 21 days after full bloom lost more fruit if the dark period was at 21.1°C than if it was at 4.4°C. Spraying these trees with carbaryl or NAA prior to the dark treatment caused no additional fruit loss. Ethephon caused defruiting at all temperatures of darkness. Spraying ‘Braeburn’/M.27 trees with a combination of carbaryl + Accel caused increased pygmy fruit development when trees were placed in the dark for 63 hours, 32 days after full bloom at temperatures from 4.4–21.1°C. In a field experiment, applications of carbaryl at 2-hour intervals from 6:00 AM to 8:00 PM to ‘Empire’/Mark trees caused similar thinning even though application temperatures ranged from 17.8–35.6°C. In another field experiment, spraying ‘Starkrimson Delicious’/Mark trees with ethephon, Accel, or carbaryl at 6:00 AM, 2:00 PM, or 8:00 PM caused similar thinning even though temperatures were 13.9°C, 33.3°C, or 19.8°C, respectively. Regression analysis of 20 years of thinning trials on five spur ‘Delicious’ strains using 50 different spray treatments indicated that higher night temperatures were more highly related to chemical thinning (accounting for about 20% of the variation) than daytime temperatures or the average of the day and night time temperatures. Degree of thinning was not significantly related to days after full bloom or fruit diameter; however, a ranking of spray treatments by chemical combination chosen for degree of expected thinning accounted for 70% of the variation. In addition, a ranking of the strains of ‘Delicious’ by ease of thinning was highly significant.
{"title":"Influence of Temperature and Darkness on Apple Fruit Abscission and Chemical Thinning","authors":"R. Byers, Alson H. Smith","doi":"10.1300/J072v03n01_04","DOIUrl":"https://doi.org/10.1300/J072v03n01_04","url":null,"abstract":"Abstract Stayman/M.27 (Malus Xdomestica Borkh.) placed in the dark for 60 hours at 21 days after full bloom lost more fruit if the dark period was at 21.1°C than if it was at 4.4°C. Spraying these trees with carbaryl or NAA prior to the dark treatment caused no additional fruit loss. Ethephon caused defruiting at all temperatures of darkness. Spraying ‘Braeburn’/M.27 trees with a combination of carbaryl + Accel caused increased pygmy fruit development when trees were placed in the dark for 63 hours, 32 days after full bloom at temperatures from 4.4–21.1°C. In a field experiment, applications of carbaryl at 2-hour intervals from 6:00 AM to 8:00 PM to ‘Empire’/Mark trees caused similar thinning even though application temperatures ranged from 17.8–35.6°C. In another field experiment, spraying ‘Starkrimson Delicious’/Mark trees with ethephon, Accel, or carbaryl at 6:00 AM, 2:00 PM, or 8:00 PM caused similar thinning even though temperatures were 13.9°C, 33.3°C, or 19.8°C, respectively. Regression analysis of 20 years of thinning trials on five spur ‘Delicious’ strains using 50 different spray treatments indicated that higher night temperatures were more highly related to chemical thinning (accounting for about 20% of the variation) than daytime temperatures or the average of the day and night time temperatures. Degree of thinning was not significantly related to days after full bloom or fruit diameter; however, a ranking of spray treatments by chemical combination chosen for degree of expected thinning accounted for 70% of the variation. In addition, a ranking of the strains of ‘Delicious’ by ease of thinning was highly significant.","PeriodicalId":117688,"journal":{"name":"Journal of Tree Fruit Production","volume":"22 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120874359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：