Expert Cherry Cultivation: Pomology Science & Genetics

Scientific Overview

This expert-level guide synthesizes current agricultural and genomic research on cultivated cherries (Prunus avium L. and Prunus cerasus L.). It is intended for pomologists, breeders, researchers, and advanced enthusiasts seeking science-based knowledge of these economically important stone fruits.

Taxonomic Classification

Level	Sweet Cherry	Sour Cherry
Kingdom	Plantae	Plantae
Clade	Angiosperms	Angiosperms
Order	Rosales	Rosales
Family	Rosaceae	Rosaceae
Genus	Prunus	Prunus
Subgenus	Cerasus	Cerasus
Species	P. avium L.	P. cerasus L.

Genomic Resources

Sweet cherry (Prunus avium):

Parameter	Value
Chromosome number	2n = 2× = 16
Genome size	~272 Mb
Predicted genes	~27,000
Reference genome	'Satonishiki' v1.0
Ploidy	Diploid (AA)

Sour cherry (Prunus cerasus):

Parameter	Value
Chromosome number	2n = 4× = 32
Genome size	~629 Mb
Subgenome composition	AA'BB (trigenomic)
Reference genome	'Montmorency' (2023)
Ploidy	Allotetraploid

Sour Cherry Origin

Recent genomic analysis reveals:

Hybrid origin: P. fruticosa (tetraploid) × P. avium (diploid unreduced gamete)
AA'BB genome composition
A and A' from P. fruticosa-like ancestor
BB from P. avium-like ancestor
Little-to-no recombination between progenitor subgenomes

Origin and Domestication

Geographic origin:

Asia Minor (Caucasus, Turkey)
Wild P. avium range: British Isles to Caucasus

Domestication timeline:

Period	Event
~800 BCE	Cultivation in Asia Minor, Greece
72 BCE	Lucullus brings cherries to Rome
1st-5th century CE	Spread across Roman Empire
16th century	Introduction to Americas

Molecular Biology

Self-Incompatibility

Gametophytic self-incompatibility (GSI):

Controlled by S-locus
S-RNase (pistil) + F-box (pollen) genes
~30 S-alleles identified in sweet cherry

S-allele notation:

Variety	S-genotype	Group
Bing	S3S4	II
Rainier	S1S4	I
Lambert	S3S4	II
Stella	S3S4'	Self-fertile

Self-fertile mutants:

S4' = non-functional S4 allele
Pollen side mutation
Key breeding target

Flowering Time Genes

Gene	Function	Effect
PavDAM	Dormancy maintenance	Chilling requirement
PavFT	Floral promoter	Early/late bloom
PavSOC1	Flowering integrator	Bloom timing

Fruit Quality Genes

Firmness:

PavPG (polygalacturonase): Cell wall degradation
PavPME (pectin methylesterase): Texture

Color:

PavMYB10: Anthocyanin regulation
PavUFGT: Anthocyanin synthesis

Size:

QTLs on LG 2, 6, 7
Complex inheritance

Global Production

Production Statistics (2024)

World cherry production:

Metric	Value
Total production	~5.0 million MT
Harvested area	~450,000 hectares
Growth trend	Increasing (Chile, China)

Top producing countries:

Rank	Country	Production (MT)	Share
1	Turkey	900,000	18%
2	USA	321,000	6%
3	Chile	502,000	10%
4	Uzbekistan	219,000	4%

Export Markets

Rank	Exporter	Value (2024)
1	Chile	$2.8 billion
2	USA	$550 million
3	Turkey	$300 million

Key importers:

China: ~415,000 MT (2024/25)
Growing 10+ consecutive years

Breeding and Genetics

Breeding Objectives

Trait	Priority	Approach
Self-fertility	High	S4' introgression
Firmness	High	MAS for PG genes
Crack resistance	High	QTL mapping
Rain tolerance	High	Physiological studies
Large fruit	Medium	QTL introgression
Low chill	Medium	DAM gene modification

Marker-Assisted Selection

Established markers:

Trait	Gene/QTL	Status
Self-fertility	S-locus	Perfect markers
Fruit size	LG 2 QTL	Linked markers
Bloom time	LG 4 QTL	Research
Firmness	PavPG	Development

Active Breeding Programs

Program	Location	Focus
Washington State Univ.	USA	Firmness, size, rain tolerance
UC Davis	USA	Low chill, quality
Agriculture Canada	Canada	Cold hardiness
Bologna/CRA-FRF	Italy	Quality, self-fertility

Physiology Research

Fruit Development

Double sigmoid growth:

Stage	Duration	Process
I	0-25 DAFB	Cell division
II	25-45 DAFB	Pit hardening
III	45-harvest	Cell expansion, ripening

Rain Cracking Physiology

Mechanisms:

Osmotic water uptake through skin
Cuticular permeability
Cell wall properties
Turgor pressure dynamics

Key factors:

Cuticular wax composition
Cuticle thickness
Fruit surface area:volume ratio
Osmotic potential gradients

Cold Hardiness

Hardiness by tissue (mid-winter):

Tissue	Sweet Cherry	Sour Cherry
Flower buds	-10 to -15°F	-20 to -30°F
Vegetative buds	-20 to -25°F	-30 to -40°F
Wood	-25 to -30°F	-35 to -45°F

Chilling Requirement

Models:

Model	Sweet Cherry	Sour Cherry
Chill hours (<45°F)	800-1200	600-1000
Utah model	800-1200	600-900
Dynamic model	45-60 portions	35-50 portions

Research Frontiers

Gene Editing

CRISPR targets:

Self-incompatibility (S-RNase knockout)
Firmness enhancement (PG modification)
Dormancy genes (DAM)
Anthocyanin pathway

Climate Adaptation

Research priorities:

Low-chill varieties
Heat tolerance during bloom
Rain cracking resistance
Extended harvest season

SWD Resistance

Research approaches:

Oviposition deterrents
Thick-skinned varieties
RNAi approaches
Sterile insect technique

Research Resources

Key Databases

Genome Database for Rosaceae (GDR)
NCBI GenBank
Cherry BAC end sequences
Prunus SNP consortium data

Important Journals

HortScience
Journal of the American Society for Horticultural Science
Tree Genetics & Genomes
Horticulture Research

Professional Organizations

American Pomological Society
International Society for Horticultural Science
Northwest Cherry Growers

Conclusion

Sweet and sour cherries represent important temperate stone fruit crops with distinct genomic backgrounds—diploid vs. allotetraploid. Recent genomic advances, including the 'Montmorency' reference genome revealing the trigenomic nature of sour cherry, enable accelerated breeding for key traits.

Critical research frontiers include developing rain crack-resistant and self-fertile sweet cherry varieties, managing spotted wing drosophila, and adapting production systems to climate change through low-chill variety development.

References available upon request. This guide synthesizes research from Nature, Horticulture Research, GDR, and university research programs.