APS_July2019

JULY 2019

Number 3

Volume 73

AMERICAN POMOLOGICAL SOCIETY F ounded in 1848 I ncorporated in 1887 in M assachusetts

2018-2019

PRESIDENT M. PRITTS

FIRST VICE PRESIDENT N. BASSIL

SECOND VICE PRESIDENT K. GASIC

RESIDENT AGENT MASSACHUSETTS W. R. AUTIO EDITOR R. P. MARINI

SECRETARY T. EINHORN

EXECUTIVE BOARD

M. WARMUND Past President

M. PRITTS President

N. BASSIL 1 st Vice President

K. GASIC 2 nd Vice President

T. EINHORN Secretary

G. PECK ('17 - '20)

E. HOOVER ('16 - '19)

A. ATUCHA ('18 - '21)

ADVISORY COMMITTEE

2016-2019 R. MORAN E. GARCIA S. YAO M. EHLENFELDT D. BRYLA 2017-2020 B. BLACK G. FERNANDEZ D. KARP I. MINAS S. SERRA 2018-2021 G. LANG T. KON D. CHAVEZ T. VASHISTH S. NAMBEESAN

CHAIRS OF STANDING COMMITTEES

Editorial R. PERKINS-VEAZIE Wilder Medal Awards J. CLARK

Shepard Award F. TAKEDA Nominations P. HIRST

Membership P. HIRST

U. P. Hedrick Award E. FALLAHI

Website M. OLMSTEAD

Registration of New Fruit and Nut Cultivars K. GASIC & J. PREECE

1

July 2019

Volume 73 CONTENTS

Number 3

Published by THE AMERICAN POMOLOGICAL SOCIETY Journal of the American Pomological Society (ISSN 1527-3741) is published by the American Pomological Society as an annual volume of 4 issues, in January, April, July and October. Membership in the Society includes a volume of the Journal. Most back issues are available at various rates. Paid renewals not received in the office of the Business Manager by January 1 will be temporarily suspended until payment is received. For current membership rates, please consult the Business Manager. Editorial Office: Manuscripts and correspondence concerning editorial matters should be addressed to the Editor: Richard Marini, 203 Tyson Building, Department of Plant Science, University Park, PA 16802-4200 USA; Email: richmarini1@gmail.com. Manuscripts submitted for publication in Journal of the American Pomological Society are accepted after recommendation of at least two editorial reviewers. Guidelines for manuscript preparation are the same as those outlined in the style manual published by the American Society for Horticultural Science for HortScience, found at http://c.ymcdn.com/sites/www.ashs.org/resource/resmgr/files/style_manual.pdf. Postmaster: Send accepted changes to the Business office. Business Office : Correspondence regarding subscriptions, advertising, back issues, and Society membership should be addressed to the Business Office, C/O Heather Hilko, ASHS, 1018 Duke St., Alexandria, VA 22314; Tel 703-836- 4606; Email: ashs@ashs.org Page Charges : A charge of $50.00 per page for members and $65.00 per page ($32.00 per half page) will be made to authors. In addition to the page charge, there will be a charge of $40.00 per page for tables, figures and photographs. Society Affairs : Matters relating to the general operation of the society, awards, committee activities, and meetings should be addressed to Michele Warmund, 1-31 Agriculture Building, Division of Plant Sciences, University of Missouri, Columbia MO 65211; Email:warmundm@missouri.edu. Society Web Site : http://americanpomological.org Blueberry and Blackberry Cultivar Evaluation in Missouri, 2011-2016 – Martin L. Kapps...............................146 Biostimulants on Fruit Yield and Quality of Mango cv. Kent Grown in Semiarid – Jackson Teixeira Lobo, Karla Dos Santos Melo De Sousa, Vespasiano Borges De Paiva Neta, Renan Nunes Pereira, Luan Dos Santos Silva, and Ítalo Herbert lucena Cavalcante..............................................................................152 Ancestors, Origin, and some Descendants of the Queensland Strawberry ‘Phenomenal’ – Anita J. Barnes and Mark E. Herrington........................................................................................................................................161 About the Cover ʻKentʼ Mango............................................................................................................................167 Performance of ‘Montmorency’ Sour Cherry ( Prunus cerasus L . ) on Size-Controlling Rootstocks at Six NC-140 Trial Locations in North America - Teryl Roper, Brent Black, Matt Stasiak, Richard Marini, John cline, Terrence Robinson, Gregory Lang, L. Anderson, Robert Anderson, J. Freer, George Greene, and Ronald Perry..................................................................................................................................................168 Multiple Sources of Eastern Filbert Blight Resistance provide Breeding Utility in Jew Jersey – Thomas J. Molnar, Shawn A. Mehlenbacher, Peninah Engel, and John M. Capik..............................................178 Wilder Medal Recipient for 2018: William ‘Dick’ Okie .................................................................................... 193 Wilder Medal Recipient for 2018: Gregory L. Reighard ....................................................................................195

146 2

J ournal of the A merican P omological S ociety

Journal of the American Pomological Society 73(3): 146-151 2019

Blueberry and Blackberry Cultivar Evaluation in Missouri, 2011-2016 M artin L. K aps 1 Additional index words: total yield, marketable yield, berry size, harvest dates, Vaccinium corymbosum, Rubus occidentalis Abstract Thirteen highbush blueberry and fourteen erect to semi-erect blackberry cultivars were evaluated for productivity at Mountain Grove in south-central Missouri. The planting was established starting in 2009 on a Viraton silt loam soil. Soil was amended with organic matter and lime or sulfur to adjust pH. Plant spacing was 1.5 m (5 ft) in-row and 3.7 m (12 ft) between rows. Drip irrigation was installed and rows mulched with shredded bark. The highest yielding highbush blueberry cultivars were ‘Aurora’, ‘Bluegold’, ‘Elliott’, ‘Legacy’, and ‘Liberty’ at 3.4 kg (7.6 lb) per plant average (2011-2016). ‘Bluecrop’, a standard cultivar in Missouri, yielded just under 1.9 kg (4.2 lb) per plant average (2011-2016). Average fruit weight was 1.6 g for the thirteen cultivars. The highest yielding blackberry cultivars were ‘Chester’ and ‘Triple Crown’ at 3.9 kg (8.6 lb) per plant average (2011-2016). Average fruit weight was 5.9 g for the fourteen cultivars. Introduction  Highbush blueberry is a North American species ( Vaccinium corymbosum L.);

processing occurs from lowbush blueberry that grows in natural, wild stands in eastern North America (Hancock, 1989a; Retamales and Hancock, 2012). Highbush cultivar selection emphasis is on characters of fruit (bloom date, flavor, longer storage, expanded harvest) and plant (chilling requirement, cold tolerance, disease and pest resistance, machine harvestability) (Hancock, 1989a; Hancock, 2009, Moore, 1993).  Blackberry is widely distributed in the temperate regions of the world and wild fruit make-up a large part of production (Strik et al., 2007). Breeding has contributed greatly to its genetic improvement in the United States with Arkansas and Oregon leading in cultivar development (Clark and Finn, 2011). Dr. James Moore, released eight blackberry cultivars from 1964 to 1997 that were well adapted to the mid-continent United States, three of them being thornless (Clark, 1999). Cultivar selection emphasis is on characters of fruit (yield, size, soluble solids, retail shipping) and plant (thornlessness, primocane

however, its culture has spread to the temperate regions of South America, Europe, China, Japan, Australia, and New Zealand (Retamales and Hancock, 2012). Selections from the wild by Elizabeth White of Whitesbog, NJ and released cultivars from the USDAbreedingwork of Frederick Coville and George Darrow from the early to mid- 1900’s form the cultivar basis of modern day production (Hancock, 1989a; Retamales and Hancock, 2012). ‘Rubel’ a wild selection is still grown today. Breeding work continued from the 1960’s through 2000 by Arlen Draper (USDA) and Paul Lyrene (University of Florida) (Hancock, 2009). The result was northern, intermediate, and southern adapted highbush blueberry cultivars (Hancock, 2006b; Hancock, 2009). Michigan and New Jersey are the major highbush blueberry producing states (Hanson and Hancock, 1990). Aside from highbush blueberry, both a substantial land area and harvest for fruit

1 Emeritus Professor, State Fruit Experiment Station of Missouri State University, Mountain Grove, MO 65711. Email: martinkaps@missouristate.edu

B lueberry and B lackberry

147

1.2 m (4 ft) wide by 15 cm (6 in) high in center were formed using a disc implement along intended plant rows to enhance surface drainage. Water holding capacity of the soil is low because of the shallow depth to the fragipan. Drip irrigation was used during periods of inadequate rainfall.  Soil reaction varies with depth from 6.5 to 4.5. Organic matter content also varies from 3.0 to 0.5%. This soil is not suitable for highbush blueberry culture without amending soil pH and organic matter. Conversely, blackberries are suited to this soil. Soil pH was adjusted to 4.7 for blueberry and 6.7 for blackberry prior to planting. Before planting, cover crops were incorporated to increase organic matter to 2.4% for blackberry and 2.9% for blueberry. Fertilizer was applied to bring phosphorus and potassium to maintenance levels [67 kg/ha (60 lb/A) available P and 280 kg/ ha (250 lb/A) exchangeable K]. Calcium, magnesium, and sulfur are typically adequate in native soil. Nitrogen as ammonium sulfate for blueberry and urea for blackberry was applied in one or two split applications annually starting at 45 kg/ha (40 lb/A) in 2009 and increasing to 110 kg/A (100 lb/A) in 2016. Sphagnum peat moss at 3.8 L (1 gal) was mixed into each blueberry planting hole. Plant rows of blueberry and blackberry were mulched with shredded bark.  Thirteen highbush blueberry ( Vaccinium corymbosum L.) and fourteen erect to semi-erect blackberry ( Rubus hybrids) were planted in 2009 (Tables 1 and 2). Eleven blackberry cultivars were floricane fruiting types. The three primocane fruiting blackberries were managed for their summer crops (Table 2). Blueberry and blackberry plant spacing was 1.5 m (5 ft) in-row by 3.7 m (12 ft) between rows. The cultivars were in randomized complete blocks with four, two-plant replications.  Blueberry plants were allowed to grow the first two seasons with only minimal pruning cuts to direct growth. Light to moderate pruning was done thereafter, removing 10 to

fruiting, disease resistance) (Clark, 2005; Clark and Finn, 2011).  Evaluation of small fruit cultivars has been an ongoing research project at the State Fruit Experiment Station of Missouri State University. Growers and the general public are interested in knowing about productive fruit cultivars for their plantings. The mid- continental climate of Missouri is suitable for temperatefruitspecies,buttherearechallenges in growing fruit in this climate. USDA Plant Hardiness Zones 5 and 6 encompass the state, so winter low temperature events and fluctuating temperatures during late winter can periodically damage fruit plants. Late spring frost is another hazard to fruit plants, although blueberry and blackberry are not prone to frost injury. Yearly precipitation is adequate for fruit plant growth; however, it can be unpredictable, going from adequate to excess to drought or in any combination of these in the same growing season. Rainfall assures a high relative humidity during the growing season which makes pests (weeds, diseases, insects) an ongoing problem for the fruit grower. Even with these challenges in fruit growing, there will always be individuals that want to grow fruit for local markets or home use. Bush and cane fruits in particular are popular choices because of their lower investment and precocious nature. Consequently, highbush blueberry and erect to semi-erect blackberry plantings were established to test the productivity of cultivars over six growing seasons. Materials and Methods  The fruit cultivars were evaluated at the State Fruit Experiment Station of Missouri State University at Mountain Grove, MO. The soil is a Viraton series, cherty silt loam soil with 2 to 5 percent slope. A fragipan occurs at 60 to 90 cm (24 to 36 in) depth with moderate water permeability above the fragipan and very low in the pan and below. This layer limits rooting depth for small fruit plants and slows internal drainage during high rainfall periods. Consequently, berms

J ournal of the A merican P omological S ociety

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planted at Mountain Grove, MO, 2009-2016. Table 1. Northern highbush blueberry cultivars, year in- troduced, origin, and harvest season planted at Mountain Grove, MO, 2009-2016. Table 1. Northern highbush blueberry cultivars, year introduced, origin, and harvest season

 Plantings were harvested one to two times per week over a four to six week bearing period. Fruit weight harvested per plant was recorded at each picking. Weight of 50 blueberries and 25 blackberries were recorded at each picking. A one-way analysis of variance was performed on the data by year using SPSS Statistics (IBM Corp., Armonk, NY 10504) and means were separated by Tukey-Kramer HSD ( P =0.05). Results and Discussion  Blackberry is well adapted to the mid-continent, temperate climate of Missouri; whereas, highbush blueberry is marginally adapted. The latter can be successfully grown on good sites when its exacting cultural requirements are met. On poorer sites, blueberry is short lived. Regardless, both fruits can be a challenge to grow with the unpredictable weather that Missouri experiences as a mid-continent state. The rise of new pests such as Spotted Wing Drosophila ( Drosophila suzukii ) along with rainfall and high humidity during the growing season requires a grower to have a regular spray program (Asplen et al., 2015). Organic production is not possible.  The usual start of bloom is mid-April for blueberry and early-May for blackberry. 11

Year

Harvest season

Cultivar

introduced Origin

Arlen

2001 2003 1952 1989 1994 2003 1987 1974 1993 2003 1988 1912

NC-USDA late

Aurora

Michigan

late

Bluecrop Bluegold Chandler

NJ-USDA mid NJ-USDA mid NJ-USDA late-mid

Draper

Michigan

early-mid

Duke Elliott

NJ-USDA early

MI-USDA

late

Hannah's Choice 2000

NJ-USDA early MD-USDA late

Legacy Liberty Nelson

Michigan

late

NJ-USDA late-mid wild selection late

Rubel

20% of the oldest canes. Blackberry plants were managed as biennial canes. Primocanes and floricanes were trained between wires of a double-T trellis. Primocanes were topped at 1.5-1.8 m (5-6 ft) height.  Tall fescue ( Festuca arundinacea Shreb.) grass was the permanent sod in the row middles. Plant rows were treated with oryzalin, diuron, or simazine at varying rates depending on the age of the plantings for pre-emergence weed control during the evaluation. Sethoxydim or glyphosate were used for post-emergence spot treatment of grass and mixed weed species, respectively during the evaluation.

Table 2. Blackberry cultivars, year introduced, origin, characteristics, and harvest season planted at Mountain Grove, MO, 2009-2016. Year Harvest Cultivar introduced Origin Characteristics season Apache 1998 Arkansas erect, floricane, thornless late Arapaho 1992 Arkansas erect, floricane, thornless early-mid Chester 1985 SIU-USDA semi-erect, floricane, thornless late Chickasaw 1998 Arkansas erect, floricane, thorny mid Kiowa 1996 Arkansas erect, floricane, thorny mid Loch Ness 1987 SCRI-UK semi-erect, floricane, thornless early Natchez 2008 Arkansas semi-erect, floricane, thornless early Navaho 1989 Arkansas erect, floricane, thornless late-mid Osage 2012 Arkansas erect, floricane, thornless early-mid Ouachita 2003 Arkansas erect, floricane, thornless mid Prime-Ark 45 2009 Arkansas erect, primocane, thorny late Prime-Jim 2004 Arkansas semi-erect, primocane, thorny mid Prime-Jan 2004 Arkansas semi-erect, primocane, thorny mid Triple Crown 1996 MD-USDA semi-erect, floricane, thornless mid Table 2. Blackberry cultivars, year introduced, origin, charcteristics, and harvest season planted at Mountain Grove, MO, 2009-2016.

B lueberry and B lackberry

149

Table 3. Yield (kg) per plant of highbush blueberry cultivars at Mountain Grove, MO, 2011-2016. Table 3. Yield (kg) per plant of highbush blueberry cultivars at Mountain Grove, MO, 2011-2016.

2011-16 2011-16

Cultivar

mean

cumulative

2011

2012

2013

2014

2015

2016

Arlen

0.53 abcd 1.02 abc 0.59 abcd 1.25 a 0.24 cd 0.28 bcd 0.28 bcd 0.57 abcd

0.95 bcd 1.48 abc 1.29 abcd 1.56 abc 1.35 abc 0.84 bcd 1.44 abc 2.04 ab 1.85 abc 0.89 bcd 0.73 cd 2.19 a 0.06 d

2.33 ab 3.86 ab 1.83 ab 3.62 ab 2.56 ab 2.38 ab 2.03 ab 3.63 ab 1.75 ab 3.85 ab 4.11 a 1.12 b 2.45 ab

2.87 ab 4.16 ab 3.08 ab 5.49 a 3.86 ab 3.69 ab 1.97 ab 2.99 ab 2.46 ab 4.20 ab 5.02 a 2.17 ab 2.98 ab

2.49 ab 4.31 a 1.37 ab 4.29 a 1.97 ab 2.77 ab 1.96 ab 4.14 a 3.84 ab 3.97 ab 3.10 ab 2.93 ab 3.16 ab

3.63 abc

2.13 3.63 1.87 3.58 2.04 2.52 1.44 3.24 1.90 3.39 3.37 2.01 2.30 2.57

12.80 21.75 11.23 21.50 12.23 15.13 19.41 11.37 20.31 20.20 12.07 13.81 15.42 8.62

Aurora

6.92 a

Bluecrop Bluegold Chandler

3.07 abc 5.29 abc 3.54 abc 4.66 abc 1.54 bc 5.89 ab 1.61 bc 5.35 abc 5.05 abc 4.91 abc 4.20 abc

Draper

Duke Elliott

Hannah's Choice 0.27 bcd

Legacy Liberty Nelson

0.90 abc 1.07 ab

0.05 d

Rubel Mean

0.29 bcd

0.56

1.28

2.73

3.46

3.10

4.28

z Means in a column not followed by a common letter are significantly different by Tukey-Kramer HSD, P ≤ 0.05.

averaged at least 3.4 kg (7.6 lb) per plant and 20.6 kg (45.5 lb) cumulative (2011- 2016). ‘Arlen’, ‘Bluecrop’, ‘Chandler’, ‘Draper’, ‘Hannah’s Choice’, ‘Nelson’, and ‘Rubel’ were moderate yielding. Yield for these seven cultivars averaged 2.1 kg (4.7 lb) per plant and 12.7 kg (27.9 lb) cumulative (2011-2016). ‘Duke’ was the remaining lowest yielding cultivar and should not be considered in Missouri based on the better yielding cultivars unless its early bearing is desired.  Berry weights varied from year to year depending on yield (Table 4). Berry weights were highest for ‘Arlen’, ‘Aurora’, ‘Chandler’, and ‘Nelson’ (2011-2016). Berries averaged 1.8 to 2.0 g; these were noticeably larger and more desirable for home or market growers. Berry weights averaged 1.4 to 1.6 g for ‘Bluecrop’, ‘Draper’, ‘Duke’, ‘Elliott’, ‘Hannah’s Choice’, ‘Legacy’, and ‘Liberty’. Berry weights for ‘Bluegold’ and ‘Rubel’ were 1.0 to 1.3 g, respectively. There is a place for small blueberries in the food processing industry. Berries 1.5 g or larger are desirable for the fresh market.  A cultivar trial conducted at Simcoe, Ontario from 1994 through 2001 had ‘Bluecrop’, ‘Bluegold’, ‘Duke’, ‘Elliott’, and ‘Nelson’ among others (Dale and Hancock, 2005). For these five cultivars, average yield was 1.6 kg (3.4 lb) per plant and average berry weight was 1.4 g. They recommended ‘Duke’ and ‘Nelson’ from that trial. ‘Nelson’

Fruit usually begin to ripening in early June for blueberry and early July for blackberry. Yields were determined from two-plant plots. Consequently, a conservative estimate of yield extrapolated to greater plant numbers or larger acreage should be made from per plant yields. Hancock et al. (1997) suggested that commercial strawberry growers might expect about one-half to two-thirds of cultivar trial yields. This assumption might also be made for other small fruits.  This trial included highbush cultivars ‘Bluecrop’, ‘Duke’, ‘Elliott’, and ‘Rubel’ that have become standards in the industry (Strik et al., 2007). ‘Bluecrop’ and ‘Rubel’ were the result of breeding and selection efforts of Frederick Coville in the early 1900’s (Hancock, 2006a). ‘Duke’ and ‘Elliott’ were later releases from the USDA breeding program under Arlen Draper (Hancock, 2009). USDA and Michigan cultivar releases from 1973 and on can be compared to the industry standards. In most cases the cumulative yields met or exceeded those standards in this trial.  Blueberry yield per plant increased through 2016 for most cultivars, but could be quite variable across cultivars within years (Table 3). No or few significant differences occurred across cultivars within years. Yields for most cultivars were similar in the last three years of the trial. The highest yielding cultivars were ‘Aurora’, ‘Bluegold’, ‘Elliott’, ‘Legacy’, and ‘Liberty’; all

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150

Table 4. Berry weight (g) of highbush blueberry cultivars at Mountain Grove, MO, 2011-2016. Table 4. Berry weight (g) of highbush blueberry cultivars at Mountain Grove, MO, 2011-2016.

2011-16

Cultivar

2011

2012

2013

2014

2015

2016

mean

Arlen

1.87 abc 2.28 ab 1.45 bcd 1.38 cd

1.92 ab 1.94 ab 1.67 bc 1.17 de 0.92 e 1.32 cde 1.35 cde 1.58 bcd 1.33 cde 1.49 bcd 1.53 bcd

1.52 bcd 1.49 bcd 1.33 bcd 1.39 bcd 1.45 bcd 1.22 bcd 1.35 bcd 1.83 ab 1.53 bcd 1.20 bcd 1.61 bc 2.43 a

1.93 abc 1.97 abc 1.54 bcd 1.16 cd 1.66 abcd 1.41 bcd 1.36 bcd 1.65 abcd 1.54 bcd 1.62 abcd 2.56 a

1.68 abcd 1.44 bcd 1.41 bcd 1.47 abcd 2.01 a 1.93 ab 1.44 bcd 1.20 cd

1.74 a 1.63 ab 1.46 abc 1.24 bcd 1.63 ab 1.35 abcd 1.47 abc 1.13 cd 1.33 abcd 1.28 abcd 0.90 d

1.78 1.79 1.48 1.30 1.99 1.62 1.45 1.44 1.66 1.60 1.48 1.98 1.04 1.58

Aurora

Bluecrop Bluegold Chandler

2.38 a

Draper

2.03 abc

Duke Elliott

2.38 a

1.66 abcd

Hannah's Choice 2.04 abc

2.00 a 1.87 ab

Legacy Liberty Nelson

1.85 abc 1.73 abcd

1.51 abcd 1.74 abc

2.36 a 0.94 d

2.28 a

2.22 ab 0.82 d

1.66 ab 1.08 cd

Rubel Mean

1.24 cde

0.89 d

1.24 cd

1.87

1.52

1.48

1.65

1.61

1.38

z Means in a column not followed by a common letter are significantly different by Tukey-Kramer HSD, P ≤ 0.05.

appears to be productive inMissouri. ‘Elliott’ was the most productive cultivar out of six in Michigan (Hancock, 1989b). ‘Bluecrop’ and ‘Rubel’ were common to that trial and this one. They attributed productivity of ‘Elliott’ to more fruiting laterals per cane, more flowers per bud, and higher fruit set. ‘Elliott’ appears to be productive in Missouri. Hancock (2006b) stated that the use of V. darrowi in the breeding of intermediate and southern types of highbush blueberry resulted in greater climate adaption. He gave intermediate type examples of ‘Arlen’, ‘Legacy’, and ‘Ozarkblue’. Presumably, these would be better adapted to Missouri. ‘Arlen’ and ‘Legacy’ were in this trial. ‘Legacy’ and ‘Ozarkblue’ were evaluated in a previous trial at the station and both were productive cultivars with respective average

yields of 4.4 kg (9.7 lb) and 3.5 kg (7.7 lb) per plant over eight years (Kaps et al., 2010).  Blackberry yield per plant was variable across cultivars within years, and over the years of the trial (Table 5). For most, but not all cultivars, yields increased through 2015 and declined in 2016. ‘Chester’ and ‘Triple Crown’ were the highest yielding cultivars; these averaged 3.9 kg (8.6 lb) per plant and 23.5 kg (51.8 lb) cumulative (2011- 2016). ‘Apache’, ‘Kiowa’, ‘Loch Ness’, ‘Natchez’, ‘Navaho’, ‘Osage’, ‘Ouachita’, and ‘Prime-Ark 45’ were moderate yielding. Yield for these eight cultivars averaged 2.1 kg (4.7 lb) per plant and 12.7 kg (27.9 lb) cumulative (2011-2016). ‘Arapaho’, ‘Chickasaw’, ‘Prime-Jim’, and ‘Prime- Jan’ were lowest yielding and should not be considered in Missouri based on better

14

Table 5. Yield (kg) per plant of blackberry cultivars at Mountain Grove, MO, 2011-2016. Table 5. Yield (kg) per plant of blackberry cultivars at Mountain Grove, MO, 2011-2016.

2011-16 2011-16

2011

2012

2013

2014

2015

2016

Cultivar Apache Arapaho Chester

mean

cumulative

1.48 bcd 0.15 f 3.16 a 0.29 ef 1.24 bcde 0.44 def 0.83 cdef

1.45 abc 0.69 cde 1.09 bcde

1.56 bc 1.89 bc 5.23 a

2.63 ab 1.10 b 6.15 a 1.42 b 4.75 ab 2.91 ab 4.10 ab 4.38 ab 3.07 ab 2.57 ab 3.52 ab 0.93 b 1.19 b 4.52 ab

3.18 bc 1.51 cd 6.70 a 0.65 cd 2.67 bcd 4.73 ab 4.54 ab 2.59 bcd 2.81 bcd 2.33 bcd 1.46 cd 0.37 d 1.65 cd 6.99 a

1.87 ab 1.03 ab 3.54 a 1.54 ab 3.33 a 3.66 a 1.98 ab 1.87 ab 1.71 ab 1.58 ab 1.45 ab 0.43 b 0.65 b 3.30 a

2.03 1.06 4.31 0.98 2.49 2.62 2.36 2.15 1.75 1.70 1.84 0.70 0.98 3.51 2.03

12.17

6.37

25.87

Chickasaw

1.19 abcde 0.77 c

5.86

Kiowa

1.39 abcd

1.57 bc

14.95 15.71 14.18 12.88 10.48 10.17 11.03

Loch Ness

1.38 abcde 2.59 b

Natchez Navaho

0.95 cde

1.78 bc

1.75 bc 0.34 ef

1.31 abcde 0.98 bc 1.29 abcde 1.26 bc

Osage

Ouachita

0.92 bcdef 1.32 bcde 1.07 bcdef

1.80 ab 1.49 abc

0.97 bc 1.79 bc 0.83 bc 0.80 bc 2.39 bc

Prime-Ark 45

Prime-Jim Prime-Jan

0.56 e

4.19 5.89

0.64 def

0.96 cde

Triple Crown

1.92 b

1.95 a

21.07 12.20

Mean

1.11

1.25

1.74

3.09

3.01

2.00

z Means in a column not followed by a common letter are significantly different by Tukey-Kramer HSD, P ≤ 0.05.

B lueberry and B lackberry

151

Table 6. Fruit weight (g) of blackberry cultivars at Mountain Grove, MO, 2011-2016. Table 6. Fruit weight (g) of blackberry cultivars at Mountain Grove, MO, 2011-2016.

2011-16

2011

2012

2013

2014

2015

2016

Cultivar Apache Arapaho Chester

mean

7.15 bc 4.83 de 5.19 cde 7.23 abc 8.73 ab 5.90 cde 9.30 a 4.44 de 7.09 bc 5.87 cde 6.10 cd 4.79 de 6.35 cd 7.25 abc

6.30 bcd 5.04 cde 5.06 cde 6.78 bc 9.09 a 4.48 de 7.13 ab 4.28 e 5.45 bcde 5.20 bcde 6.18 bcde 4.81 cde 4.99 cde

7.14 b 3.65 e

6.65 bc 4.67 cdef 4.41 def 5.57 cdef

8.49 abc 5.42 de 5.06 de 5.59 cde 4.82 de 8.78 ab 4.38 de 5.36 de 5.51 cde 7.07 abcd

7.82 ab

7.26 4.73 4.98 6.29 9.67 4.75 7.88 4.41 5.50 5.31 6.16 4.60 4.47 6.94 5.92

4.76 bcde 5.42 bcde 6.42 abcd 4.53 bcde 7.23 abc 4.81 bcde 5.20 bcde 4.83 bcde 6.51 abcd 4.40 bcde 3.94 cde 7.04 abc

4.76 cde 6.17 bcd 9.81 a 4.57 de 6.82 bc 4.86 cde 4.20 de 4.86 cde 5.20 bcde

Chickasaw

Kiowa

10.09 a

10.02 a

10.28 a

Loch Ness

4.19 def

Natchez Navaho

8.00 b 3.71 f

Osage

5.72 cdef 5.58 cdef 5.89 cde 4.82 cdef 3.97 ef 6.57 bc

Ouachita

Prime-Ark 45

Prime-Jim Prime-Jan

3.80 e 3.62 e 7.07 b

4.96 de 3.94 e

Triple Crown

6.64 bc

7.06 abcd

Mean

6.44

5.82

5.47

5.70

6.18

5.94

z Means in a column not followed by a common letter are significantly different by Tukey-Kramer HSD, P ≤ 0.05.

yielding cultivars. Additionally, the thorny cultivars ‘Chickasaw’, ‘Kiowa’, ‘Prime-Ark 45’, ‘Prime-Jim’, and ‘Prime-Jan’ would likely not be considered by home or market growers in Missouri considering the better yielding thornless cultivars.  Fruit weight was highest for ‘Kiowa’ at 9.7 g, one of the high yielding, thorny cultivars that would likely not be considered by home or market growers (2011-2016) (Table 6). ‘Apache’, ‘Natchez’, and ‘Triple Crown’ had the next highest fruit weight average of 7.4 g (2011-2016). Fruit weight averages of the remaining cultivars were 4 to 6 g. Larger fruit size is always appealing to both picker and consumer, so this could be a determining factor in cultivar selection assuming that yield is reasonably good. ‘Apache’, ‘Natchez’, and ‘Triple Crown’ fall into this latter category. Literature Cited Asplen, M. K., G. Anfora, A. Biondi, D.S. Choi, D. Chu, K.M. Daane, P. Gibert, A.P. Gutierrez, K.A. Hoelmer, W.D. Hutchison, R.Isaacs, Z. Jiang, Z. Kárpá, M.T. Kimura, M. Pascual, C.R. Philips, C. Plantamp, L. Ponti, Gábor Vétek, H. Vogt, V.M. Walton, Y. Yu, L. Zappalà, and N. Desneux. 2015. Invasion biology of spotted wing Drosophila ( Drosophila suzukii ): a global perspective and future priorities. J. Pest Sci. 88:469-494. Clark, J.R. 1999. The blackberry breeding program at the University of Arkansas: Thirty-plus years of progress and developments for the future. Acta Hort. 505:73-77.

Clark, J.R. 2005. Changing Times for Eastern United States Blackberries. HortTechnology 15(3):491-494. Clark. J.R. and C.E. Finn. 2011. Blackberry breeding and genetics. Fruit, Vegetable and Cereal Science and Biotechnol. pp. 27-43. Dale, A. and J.F. Hancock. 2005. Highbush blueberry cultivar trial in Ontario, Canada. International. J. Fruit Science 5:73-76. Hancock, J.F. 1989a. Blueberry Research in North America. Acta Hort. 241:19-30. Hancock, J.F. 1989b. Why is ‘Elliott’ so productive? A comparison of yield components in 6 highbush blueberry cultivars. Fruit Var. J. 43:106-109. Hancock, J.F., B.L. Goulart, J.J. Luby and M.P. Pritts. 1997. The strawberry matted row: Practical cropping system or dated anachronism? Adv. Strawberry Res. 16:1-4. Hancock, J.F. 2006a. Highbush blueberry breeders. HortScience 41:20-21. Hancock, J. 2006b. Northern highbush blueberry breeding. Acta Hort. 715:37-40. Hancock, J.F. 2009. Highbush blueberry breeding. Latvian J. Agron. 12:35-38. Hanson, E.J. and J.F. Hancock. 1990. Highbush blueberry cultivars and production trends. Fruit Var. J. 44:77-81. Kaps, M.L., P.L. Byers, and M.B. Odneal. 2010. Productivity comparison of fourteen highbush blueberry cultivars in Missouri, 2000-2008. J Amer. Pom. Soc. 64:218-225. Moore, J.N. 1993. Blueberry cultivars of North America. HortTechnology 3:370-374. Retamales, J.B. and J.F. Hancock. 2012. Blueberries, Crop Production Science in Horticulture 21. CABI. Cambridge, MA pp.323. Strik, B.C., J.R. Clark, C.E. Finn and M.P. Bañados. 2007. Worldwide Blackberry Production. HortTechnology 17(2):205-213.

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Journal of the American Pomological Society 73(3): 152-160 2019

Biostimulants on Fruit Yield and Quality of Mango cv. Kent Grown in Semiarid J ackson T eixeira L obo 1 , K arla D os S antos M elo D e S ousa 1 , V espasiano B orges D e P aiva N eto 1 , R enan N unes P ereira 1 , L uan D os S antos S ilva 2 , and Í talo H erbert L ucena C avalcante 1* Abstract  Mango ( Mangifera indica L.) is the second most exported fruit of Brazil, which is especially grown in São Francisco Valley, a semi-arid region. One of the main cultivars exported is ‘Kent’ which has favorable physical- chemical characteristics, but irregular production and low fruit retention on the tree. Thus, the objective of the present study was to evaluate yield and postharvest quality of ‘Kent’ fruits as a function of foliar spray with biostimulants. The experiment followed a randomized complete block design with five treatments, four replications per treatment and four plants per replication evaluated in two consecutive years (2016 and 2017). The treatments consisted of foliar sprays with plant biostimulants, as follows: T1) Control (without biostimulants); T2) Biostimulant containing nutrients and L-α-amino acids; T3) Biostimulant containing nutrients and Lithothamnium algae extract; T4) Biostimulant containing nutrients and sucrose; and T5) Biostimulant containing nutrients, free amino acids and Lithothamnium algae extract. Biostimulants affected fruit yield and quality of ‘Kent’ fruits in distinct ways between seasons. The biostimulant T2 and T5, promoted the highest fruit yields, and maintained the postharvest quality of the fruits required by the European market. Additional index words: Mangifera indicia L., post-harvest, production system

 Mango ( Mangifera indica L.) is the second most exported fruit of Brazil, with 99 % of the national production coming from the Southeast and Northeast regions (IBGE, 2016). In the Northeast, the Pernambuco and Bahia states have 32,378 ha of mango trees, especially Petrolina and Juazeiro counties, located in São Francisco Valley, a semi-arid region (IBGE, 2016).  Among the cultivars grown in São Francisco Valley, ‘Kent’ has been outstanding in the international market, as it has a pleasant flavor, yellowish-green to purple- red color, high soluble solids concentration and reduced fiber content (Siddiq et al., 2017). Despite the favorable physical- chemical and sensory characteristics of the

fruits, ‘Kent’ has irregular production due to difficult flowering management and low fruit retention (Ramírez and Davenport, 2010).  The fruit abscission in mango is a complex phenomenon, probably associated with the plant genotype (cultivar), competition for photoassimilates, lack of pollination and/ or non-balanced fertilization, pests and diseases, high temperatures and nutritional and hormonal imbalances (Singh et al., 2005).  Biostimulant substances have been used in some studies to reduce fruit abscission and, consequently to increase mango fruit yield. Biostimulants have physiological effects similar to phytohormones, acting in physiological processes (Nardi et al., 2016).

1 Department of Agricultural Science, Federal University of São Francisco Valley, Rod. BR 407 - km 190 - Lote 543 PSNC, Petrolina, Pernambuco State, 56.300-900, Brazil. 2 Department of Agricultural Science, Federal University of Piaui, Av. Manoel Gracindo - km 01 - Planalto Hori- zonte, Bom Jesus, Piaui State, 64.900-000, Brazil. * Corresponding author. E-mail: italo.cavalcante@univasf.edu.br We are grateful thank to FACEPE (Foundation for Support of Science and Technology of Pernambuco State) for granting the scholarship under grant number IBPG-1002-5.01/15.

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Fig. 1. Maximum, minimum and average air temperature, relative air humidity and rainfall recorded during the execution of the experiment. Petrolina, Pernambuco, Brazil (A − 2016; B − 2017). 362 Figure 1 . Maximum, minimum and average air temperature, relative air humidity and rainfall 363 recorded during the execution of the experiment. Petrolina, Pernambuco, Brazil (A – 2016; B 364 2017).

Materials and Methods Plant Material and Growing Conditions  Ten year-old ‘Kent’ mango ( Mangifera indica L.) trees, with uniform size and vigor were used in this study. The experiment was performed in two consecutive years (2016 and 2017) in an experimental orchard located in Petrolina (09°09 ' S and 40º22 ' W; at an altitude of 365.5 m above sea level), Pernambuco, Brazil. The climate of this region is classified as Bsh (Köeppen), which corresponds to a semi-arid region.  During the experiment, climatic data were collected by a meteorological station (Fig. 1). Chemical characteristics of the soil before the experiment are in Table 1. The orchard nutritional status was also determined by leaf analysis before the experiment, as can be seen in Table 2. Leaves were collected in the middle part of the canopy, on 8 July 2016 and 10 June 2017. Leaves were chemically analyzed after they were washed and rinsed with distilled water and dried at 65 °C to a constant biomass following methodology

Jarande et al. (2013) applied nutrients plus sucrose to ‘Kesar’, Khattab et al. (2016) studied the effect of a biostimulant containing calcium, boron and amino acids on different mango cultivars (but not ‘Kent’), and Ahmed et al. (2015) demonstrated the benefits of algae extract associated with nitrogen fertilization on ‘Taimour’.  Ebeed and Abd El-Migeed (2005) reported positive results on fruit characteristics and postharvest quality with the use of 10 % sucrose combined with 0.3 % potassium citrate for ‘Fagri kalan’ mango. However, the effects of biostimulants on the physical- chemical quality of mango fruits are scarce in the scientific literature, although they are crucial characteristics for the mango industry, since fruit postharvest quality depends on several factors such as plant genetics, climate and production practices performed in the orchard. In this sense, the objective of this study was to evaluate ‘Kent’ fruit yield and postharvest quality as a function of foliar spray with biostimulants.

365 366 367 368 369 370 371 372 373

Table 1. Chemical soil characteristics (0-40 cm soil depth) in the experimental site before the 332 experiment. 333 pH O.M. P K + Na + Ca 2+ Mg 2+ Al 3+ (H + Al) S.B. V H 2 O g/100g mg/dm 3 --------------------- cmol c /dm 3 -------------------------- % 6.3 12 16 0.35 0.13 4.5 1.8 0 1.92 6.78 78 P, K and Na: Mehlich 1 (HCl + H 2 SO 4 ); Ca, Mg and Al: KCl 1 M extractor. O.M.: organic matter; 334 S.B.: sum of bases; V: percent base saturation; mg: milligrams; cmol c : centimole of charge; dm 3 : 335 cubic decimeter. Table 1. Chemical soil characteristics (0-40 cm soil depth) in the experimental site before the experiment. P, K and Na: Mehlich 1 (HCI + H 2 SO 4 ); Ca, Mg andA1: KC1 1 M extractor. O.M.: organic matter; SB.: sum of bases; V: percent base saturation; mg: milligrams; cmol c : centimole of charge; dm 3 : cubic decimeter.

336 337

c

154 336 337 Table 2. Leaf nutrient concentrations of mango cv. Kent before the treatments when leaves were 338 sampled on 8 July 2016 and 10 June 2017. 339 J ournal of the A merican P omological S ociety Table 2. Leaf nutrient concentrations of mango cv. Kent before the treatments when leaves were sampled on 8 July 2016 and 10 June 2017. cubic decimeter.

N

P

K

Ca

Mg

Mn

Fe

Zn

B

Year 2016 2017

------------ g/kg --------------

--------- mg/kg ---------

17.78 13.49

1.15 21.00 10.18 0.98 211.77 39.65 16.03 19.77

N: Kjeldahl; P: spectrometry with yellow vanadate; K: Flame photometry; Mg, Ca, Fe, Zn and Mn: Spectrophotometry of atomic absorption; B: spectrometry with azometin-H 8.90 15.60 1.50 171.78 41.28 15.08 97.65 N: Kjeldahl; P: spectrom try with yellow vanadate; K: Flame photometry; Mg, Ca, Fe, Zn and Mn: 340 Spectrophotometry of atomic absorption; B: spectrometry with azometin-H 1.54

341 342 343 344 345 346 347 348 349 350 351

pre-flowering and full flowering of mango in São Francisco Valley, properly described by Genú and Pinto (2002) and Cavalcante et al. (2016), which compositions are described in Table 3.  The treatments were applied in three phases: pre-flowering, beginning of flowering and full flowering (Fig. 2), according to the mango phenology described by Ramírez and Davenport (2010). The doses of each biostimulant followed the manufacturer recommendation but the total volume applied was 3.0 L of the mixture (biostimulant + water) per plant. Evaluations and Statistical Analysis  Commercially mature fruits were manually harvested in a single day when they

described by M alavolta et al. (1997).  The plants, spaced 5.0 m between the rows and 3.0 m between the plants, were daily irrigated (Micro sprinkler) with one emitter per plant, to provide about 60 L·h -1 each, based on evapotranspiration registers recorded by a meteorological station and corrected according to the mango culture coefficient (Kc) defined by Genú and Pinto (2002). All management practices such as pruning, control of weeds, pests and diseases, plant growth regulator (Cultar ® , Paclobutrazol) for gibberellin synthesis inhibition and dormancy break were performed following the instructions of Genú and Pinto (2002). The dose of Cultar ® 250 SC (Syngenta Crop Protection, Paulinia, São Paulo, Brazil), equivalent to 2.25 g·m -1 of active ingredient (a.i.) was applied each year at the rate of 9.0 mL per linear meter of tree canopy diameter diluted in 2 liters of water and applied as a soil drench once under the canopy dripline. Dormancy break included three foliar sprays with calcium nitrate (2.5%) at 90, 97 and 104 days after paclobutrazol application. Nutrients were applied through a fertirrigation system, according to plant demand (Genú and Pinto, 2002). Trees were manually pruned to synchronize vegetative flush events in the canopy. Treatments and Experimental Design  The experiment was a randomized complete block design with five treatments, four replications per treatment and four plants per replication evaluated in two consecutive years (2016 and 2017). The treatments were defined considering the plant demands and physiological changes that occur during the

Fig. 2. Plant stages when the treatments (biostimu- lants) were sprayed: pre-flowering on 10 June 2017 (A), beginning of flowering on 22 June 2017 (B), and full flowering on 12 July 2017 (C). 374 Figure 2 . Plant stages when he treatments (biostimula ts) were sprayed: pre-flo 375 2017 (A), beginning of flowering on 22 June 2017 (B), and full flowering on 12 Ju

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Table 3. Treatment description and composition of the biostimulants used in the experiment. Table 3 . Treatment description and composition of the biostimulants used in the experiment. 352 Treatment Composition Dose T1 Without biostimulants spray --- T2 Nitric nitrogen 10.0%, potassium oxide 5.0%, calcium oxide 7.15%, Magnesium oxide 1.2%, boron 0.1% and l-α amino acid 0.35% 3.0 mL·L -1 T3 1.0 mL·L -1

Organic nitrogen 5.0%, nitric nitrogen 1.2%, ammoniacal nitrogen 1.3% and amide nitrogen 2.5%. Raw materials: water, soybean pie, liquid sodium hydroxide, urea, ammonium nitrate, citric acid, Lithothannium seaweed extracts and sodium molybdate Organic nitrogen 6.0%, Organic carbon of biologically origin 20.8% and total protein 31.0%. Raw materials: water, soybean pie, liquid sodium hydroxide, leonardite, Lithothannium seaweed extracts, citric acid, free amino acids Calcium 8.0%, boron 2.0% and Sucrose

T4

2.5 mL·L -1

T5

2.5 mL·L -1

353 354 355 356 357 358 359 360 361

reached physiological maturity which was characterized by pulp color (yellow cream), following the fruit selection parameters recommended by the Brazilian Program for Horticulture Modernization (2004) for commercial farms. Production per plant was measured using a precision scale (0.5 grams of precision) for calculating fruit yield (t ha -1 ).  After harvest, the fruits were stored for 23 days at 20°C until reaching the matura- tion stage 4 (Brazilian Program for Horti- culture Modernization, 2004). Postharvest analyses were performed on 10 fruits per replication, as outlined by Zenebon et al. (2008) and included the usual parameters: length and width were measured with a digital paquimeter (0.01 mm–300 mm) and expressed in cm; fruit mass was measured using a precision balance (0.01 g precision) and expressed in g; fruit firmness (10 5 ·N/m 2 ) was measured using a fruit firmness tester on both fruit sides; soluble solids concen- tration (SS), expressed as percentage (%),

were measured with an Abbe ® refractometer (Bausch and Lomb, Rochester, NY, USA); for the titratable acidity (TA), 20 g of macer- ated fruit pulp from a fruit was brought to a final volume of 100 mL by adding distilled water. A 20 mL sample was taken from the mixture, and three to four drops of phthalein were used as an indicator. This suspension was titrated with 0.1 N sodium hydroxide (NaOH). The results were expressed as g of citric acid/100 g pulp; SS/TA ratio; and num- ber of fruits with the physiological disorder known as internal breakdown.  Statistical analyses included analysis of variance (ANOVA) by year and means were compared withTukey’s test. All the calculations were performed using the ASSISTAT Statistical Program (ASSISTAT 7.7, UFCG, Campina Grande, Brazil) and terms were considered significant at P ≤ 0.05. Results and Discussion  In the first season (2016), trees with T5

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 The average fruit length (FL) in 2016 was 108.74 mm (Fig. 4A). In 2017, the highest FL was recorded for T5 (125.48 mm), similar to T1, T3, and T4, but different from T2, and the difference between T5 and T2 was 7.38 mm (Fig. 4A).  Fruit width (FW) was affected by treatment in both 2016 and 2017 (Fig. 4B). In 2016 the biostimulants produced fruits with similar FW and an average value of 110.01 mm, 20 % higher than the control treatment (T1), which was only 91.47 mm. In 2017, the best treatments were T5 (110.34 mm) and T1 (106.95 mm), which was similar to the other treatments. Modesto et al. (2016) studied different mango cultivars and verified that for a given cultivar, fruit width can vary with the season due to the crop seasonality, plant’s intrinsic factors, water availability, and temperature ranges. Plant biostimulants may be able to reduce these effects and standardize FW.  In 2017 FL and FW measurements were highest for T5 that is in agreement with Battacharyya (2015), who found similar results with the combination Lithotamnium seaweed extract and free amino acids. According toAslam et al. (2010) the seaweed extract contains calcium, copper, manganese, zinc, iron, potassium, magnesium, and cobalt, essential nutrients for plant development that contributed to fruit growth.  The fruit mass was affected in both evaluation years (Fig. 4C). In 2016, T3 and T4 treatments were higher than the others, with averages of 543 and 533g, respectively; these averages are similar to 504 g (T5) and 449 g (T2), while fruits with lower mass were produced by the control treatment. In 2017, fruit mass was highest for T5 and it was 49 % higher than for trees treated with T3 (496.18 g), and 14 % higher than the control.  ‘Kent’ fruits are traditionally produced with a focus on the export market, and therefore, the grade standards for those markets are considered for comparison purposes, especially the European Union, the main purchaser of Brazilian’s mangoes

had the highest yield (Fig. 3), 11.3 t ha -1 higher than the control treatment (T1). T4 reduced yield 21 % compared to T1, which was an unexpected result, considering the biostimulant composition. Non-treated plants (T1), plants sprayed with biostimulant containing water soluble nutrients and L-α- amino acids (T2), and biostimulant containing water soluble nutrients and Lithothamnium algae extract (T3) had similar yields (Fig. 3). In 2017, T2 had the highest yield and it was significantly greater than the control (T1). All treatments except the control produced higher yields in 2017 than in 2016. In the entire experiment the lowest fruit yield was 22 t ha -1 , recorded for T4 in 2016 and it was higher than the Brazilian average 16.1 t ha -1 , and even higher than yields reported for other countries, such as China (8.2 t ha - 1 ), India (7.3 t ha -1 ), and Mexico (8.9 t ha -1 ) (FAO, 2017), demonstrating the potential of mango trees in São Francisco Valley.  In 2016, only the width (FW) and fruit mass were affected by the treatments, while in 2017 all variables (fruit length, fruit width, fruit mass and fruit firmness) were affected by biostimulants (Fig. 4). Fig. 3. Fruit yield of mango cv. Kent as influenced by biostimulants in two consecutive seasons (2016 and 2017) Bars with common capital letters (2016) and common lower case letters (2017) do not differ at the 5% level by Tukey's test. Error bars indicate standard error of the mean. Treatments description in Table 3.

ld of mango cv. Ke t as influe ced by biostimulants in two consecutive seasons ars with common capital letters (2016) and common lower case letters (2017) do 5% level by Tukey’s test. Error bars indicate stand rd error of the mean. tion in Table 3.

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Fig. 4. Fruit length (A), width (B), fruit mass (C), and firmness of mango cv. Kent (D) as influenced by bio- stimulants in two consecutive seasons (2016 and 2017). Bars with common capital letters for 2016 and for lower case letters for 2017 do not differ at the 5% level, by Tukey's test. Error bars indicate standard error of the mean. Treatement descriptions in Table 3. 398 Figure 4. Fruit length (A), width (B), fruit mass (C), and firm ess of mango cv. Kent (D) as 399 influenced by biostimulant i two consecutive seasons (2016 and 2017). Bars with common capital 400 letters for 2016 and for lower case letters for 2017 do not differ at the 5% level, by Tukey’s test. 401 Error bars indicate standard error of the ean. Treatments description in Table 3.

(Araújo and Garcia, 2012).  According to United Nations Economic Commission for Europe (UNECE, 2017) standard FFV-45 concerning marketing and commercial quality control of mangoes, the fruits for export must be at least 100 g and are classified by weight: size code A (100-350 g), size code B (351-550 g), size code C (551- 800 g), and size code D (> 800 g). In 2016 all treatments produced ‘size code B’ fruits and in 2017 the fruits of T1, T4, and T5 were ‘size code C’, and T2 and T3 corresponded to ‘size code B’.  According to the Normative Instruction of the Brazilian Department of Agriculture (Brazil, 2012), mango fruits are classified by caliber, which corresponds to the number of fruits in a commercial box. Traditionally ‘Kent’ is sold in boxes containing 4 kg of

fruit; considering this criteria, the fruits produced in 2016 are classified as: T1 (10 caliber), T2 (9 caliber), T3 (7 caliber), T4 (7 caliber) and T5 (8 caliber); in 2017 the classification was:T1 (6 caliber), T2 (7 caliber), T3 (8 caliber), T4 (6 caliber) and T5 (5 caliber).  Exporting fruits for fresh consumption should be 6 to 10 calibers, while the 4 and 5 caliber fruits are usually commercialized for the fruit processing industry according to the classification adopted by fruit growers in the São Francisco Valley and exported to European Union.  European consumers prefer medium-sized fruits, with 8 and 9 calibers (Araújo and Garcia, 2012). Therefore, fruits produced by T2 and T5 in 2016 were suitable for the European market while in 2017, fruits from

402 403