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Reprinted from Volume 8G of the Proceedings of the STATE HORTICULTURAL SOCIETY \s Miami, November 6-8,1973 ENHANCEMENT OF RED COLOR ON WITH AN ANTITRANSPIRANT Charles R/JBarmoke" sticker-extender, Nu-Film-17. Fruit were harvested for color determinations 7 to 17 days after spray IFAS Agricultural Research and Education Center ing. Lake Alfred Color measurements were made in the labora Donald H. Spalding tory with a Hunterlab D25 Color Difference Meter 1 day after harvest Measurements were made in Agricultural Research Service, U. S. Department an area of max red color on 10 to 15 fruit of each of Agriculture treatment and the value expressed as the a/b ratio. Miami This value is used to express a scale of red to and yellow to green. Robert T. McMillan, Jr IFAS Agricultural Research and Education Center Results and Discussion Homestead The red color response to VG varies among cv. (Table 1). Fruit surface of the 'Irwin' cv. is Abstract. Preharvest application of the anti- transpirant poly-l-p Menthen-8-9 diyl, Vapor Gard (VG), at concn of 2 to 3% accentuated the Table 1. Effect of preharvest VG red color on '', '', and 'Irwin' mangos. application on the accentuation The material can be applied with the last fungi of the external red color (a/b) cide application 1 to 2 weeks prior to harvest. of the fruit of several cv.

The external color of fruits produced in Color value Florida is an important factor in consumer appeal. Cultivar Treatment a/b With adequate disease control, color development of most yellow cv. is no problem. However, color Irwin2 Control 2.85x+ .22 development of some red cv. can be extremely 2.5% VG 3.11 + .17 variable. The red color is due to anthocyanins (1) 57. VG 3.55x+ .19 and its development is affected by light exposure. Control 2.02 + .55 With some cv. harvested mature but firm (com Palmery mercial maturity), anthocyanin development is re 1% VG 2.10 + .49 duced when fruit are ripened at 21 °C or higher 3% VG 2.06 + .40 (3). In 1972, preharvest application of VG was 57c VG 2.45 + .45 found to increase red color development on 'Irwin' Kenty Control 1.48 + .23 and 'Keitt' mangos (1). This phenomenon has been 27. VG 1.70 + .21 studied for 2 years and VG was first used com mercially this year to enhance the color of mangos. Keitty Control 0.72 + .30 The purpose of this study was to determine the 17. VG 0.92 + .33 effect of different VG concn on red color of several 37. VG 1.10 + .32 mango cv. 57. VG 1.17 + .32

Materials and Methods Control 0.97x+ .18 Tests were conducted on fruiting trees of 57, VG l.llx+ .21 'Irwin', 'Lippens', 'Keitt', 'Kent', and '' located in south Dade County, Florida. VG was Fruit harvested 17 days after applied at concn of 1 to 59c at the time of the VG application. last fungicide application to the fruit replacing the y •'Fruit harvested 7 days after VG Fla. Ajtr. Expt. Sta. J. Series No. 6127. Cooperative re application. search of the University of Florida, IFAS Agricultural Re search and Education Center, Lake Alfred, and the U. S. Department of Agriculture, Miami. Florida. Data taken from Barmore, et al.(1) ."i

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ConclusionsCone stly bright red when tree *£*?£% VG „„„t intended to *££»£X f IT£.redAir. rfandtroitlessharvestedaccentuatedwhen-"f»";„ Jripened^ at I cnhancing^ redonc°lor-cv^^ere^"^harvestpostharvestredred color «£^SaS'the(31 VGredtreatmentscolor comparedof botnw^* ^Mntrols d^ deve,oPn,entt 1S marginal.s red.^.^01 ^ ^ cOTCn ^o{ ,1 also have been reported to i effect VG ed should be sum n ol VG are "ntagehaTalsoofbeenrednotedsurfaceon the««£>^Tom y^kir,s' havecv. a *«.^red expensivecolor <£*££*b»tr chloropV*"Baseddegrada;on the •Palmer' fruit at commercial m ntagc stovage (unpubl.sn vations, 2 to „•Ifred color which covers »J*%faAm was ;'csuUsresults presentedprinted and on Bernfield ^ ^^ha„Mt „ ^ surface. Accentuation of:*»r*^ ^ ^3* ^VG applieda?P,ied !1to 2we*sweeks P^P o{ ,, •^^t^rSST^ examined£ this

maturity have red '"^ 0- *™» TtJ "yenow on »'X /enSlnrng portion being ^ tender (2). to the sunlight, the r color ]S substan t itcrature Cited Treen. The intensity of the > mentl0„ed Ll . u T. McMiUan. ?ially less than that of *«J „ greater on cv. The amount of «d colo ^ ^ ea •Kenf than on Keiu. 3 mA r,% {or pSeatTon^n«ortScrcc.T Mf?. yi^ P 2. Barmore. C. «-. control of »"\jcation of on anti the*th'Keit^VG atincreaseS* for mhe*eJKe* dsurfacefM .Kelttare "»?; i^Sd * ' ^£",5? R^on. Amer. See. showing red color has also frU,tKntrant Plus Benomyl- Proc Cnrnpbell. mango (D- Q on color development of SgrKepKNod^.9P.3. Hatton. T. T- e of Florida m •Uppens"The effectwas minimal;of VG onThe sta ^ ^cv does showrelr^Clru^oseda small amount rf»^to directfa rcdsunhgh,, has