Citrus Fruits:Photos
Citrus Pest and Nutritional Disorder Photos
Contents
- 1 Amorphous_plugs
- 2 Bark_cracking
- 3 Bark_cracking
- 4 Bark_scaling
- 5 Bark_scaling
- 6 Blight
- 7 Blight
- 8 Blight
- 9 Blight
- 10 Browning
- 11 Browning
- 12 Bud-union_abnormality
- 13 Bud-union_abnormality
- 14 Bud-union_abnormality
- 15 Bud-union_abnormality
- 16 Bud-union_abnormality
- 17 CEV
- 18 CEV
- 19 CEV
- 20 CEV
- 21 CEV
- 22 Citrus_blight
- 23 Citrus_blight_(cause_unknown)
- 24 Citrus_blight_(cause_unknown)
- 25 Citrus_blight_(cause_unknown)
- 26 Citrus_blight_(cause_unknown)
- 27 Citrus_blight_(cause_unknown)
- 28 Citrus_cachexia_viroid
- 29 Citrus_cachexia_viroid
- 30 Citrus_cachexia_viroid
- 31 Citrus_Cachexia_viroid
- 32 Citrus_Cachexia_viroid
- 33 Citrus_concave_gum
- 34 Citrus_concave_gum
- 35 Citrus_concave_gum
- 36 Citrus_cristacortis
- 37 Citrus_cristacortis
- 38 Citrus_cristacortis
- 39 Citrus_cristacortis
- 40 Citrus_cristacortis
- 41 Citrus_cristacortis
- 42 Citrus_exocortis_viroid
- 43 Citrus_exocortis_viroid
- 44 Citrus_exocortis_viroid
- 45 Citrus_exocortis_viroid
- 46 Citrus_exocortis_viroid
- 47 Citrus_exocortis_viroid
- 48 Citrus_grandis
- 49 Citrus_greening
- 50 Citrus_greening
- 51 Citrus_greening
- 52 Citrus_greening
- 53 Citrus_greening
- 54 Citrus_greening
- 55 Citrus_greening
- 56 Citrus_greening
- 57 Citrus_greening
- 58 Citrus_greening
- 59 Citrus_greening
- 60 Citrus_impietratura
- 61 Citrus_impietratura
- 62 Citrus_leprosis_rhabdovirus
- 63 Citrus_leprosis_rhabdovirus
- 64 Citrus_leprosis_rhabdovirus
- 65 Citrus_leprosis_rhabdovirus
- 66 Citrus_psorosis
- 67 Citrus_psorosis
- 68 Citrus_psorosis
- 69 Citrus_psorosis
- 70 Citrus_psorosis
- 71 Citrus_psorosis
- 72 Citrus_psorosis
- 73 Citrus_psorosis
- 74 Citrus_psorosis
- 75 Citrus_psorosis
- 76 Citrus_psorosis
- 77 Citrus_psorosis
- 78 Citrus_psorosis
- 79 Citrus_psorosis
- 80 Citrus_psorosis
- 81 Citrus_tatterleaf_capillovirus
- 82 Citrus_tatterleaf_capillovirus
- 83 Citrus_tatterleaf_capillovirus
- 84 Citrus_tatterleaf_capillovirus
- 85 Citrus_tatterleaf_capillovirus
- 86 Citrus_tatterleaf_capillovirus
- 87 Citrus_tatterleaf_capillovirus,
- 88 Citrus_tristeza_closterovirus
- 89 Citrus_tristeza_closterovirus
- 90 Citrus_tristeza_closterovirus
- 91 Citrus_tristeza_closterovirus
- 92 Citrus_tristeza_closterovirus
- 93 Citrus_tristeza_closterovirus
- 94 Citrus_tristeza_closterovirus
- 95 Citrus_tristeza_closterovirus
- 96 Citrus_tristeza_closterovirus
- 97 Citrus_tristeza_virus
- 98 Citrus_variegation_ilarvirus
- 99 Citrus_variegation_ilarvirus
- 100 Citrus_variegation_ilarvirus
- 101 Citrus_variegation_ilarvirus
- 102 Citrus_vein_enation/woody_gall
- 103 Citrus_vein_enation/woody_gall
- 104 Citrus_viroid_symptoms
- 105 Citrus_viroids
- 106 Citrus_viroids
- 107 CIVV
- 108 CIVV
- 109 CIVV
- 110 CIVV
- 111 CIVV
- 112 CIVV
- 113 CIVV
- 114 CIVV
- 115 Concave_gum_disease
- 116 Concave_gum_disease
- 117 Concave_gum_disease
- 118 Concave_gum_virus
- 119 Concave_gum_virus
- 120 Cristacortis
- 121 Cristacortis
- 122 Cristacortis
- 123 Cristacortis
- 124 Cristacortis_and_concave_gum_disease
- 125 Cristacortis_infection
- 126 Cristacortis_infection
- 127 Cristacortis_infection
- 128 CTLV
- 129 CTLV
- 130 CTLV
- 131 CTLV
- 132 CTLV
- 133 CTLV
- 134 CTLV
- 135 CTV_isolate
- 136 CVV-2
- 137 Diaphorina_citri
- 138 Diaphorina_citri
- 139 Drill
- 140 Elsinoe_fawcettii
- 141 Female_Mexican_fruit_fly
- 142 Graduated_burette
- 143 Grapefruit_infected_
- 144 greasy_spot,_Mycosphaerella
- 145 Greening_infection
- 146 Greening_infection
- 147 Greening_infection
- 148 Greening_infection
- 149 Greening_infection
- 150 Greening_infection
- 151 Guignardia_citricarpa
- 152 Gum_pocket
- 153 Gumming
- 154 Gumming
- 155 Gumming_and_Cachexia
- 156 Gummy_bark_symptoms
- 157 Gummy_bark_symptoms
- 158 Gummy_bark_symptoms
- 159 Hand_drill
- 160 Impietratura_infection
- 161 Impietratura_infection
- 162 Impietratura_infection
- 163 Impietratura_infection
- 164 Impietratura_infection
- 165 Impietratura_infection
- 166 Injection_procedure
- 167 Inverse_pitting_on_orange
- 168 Mandarin,_Citrus_reticulata
- 169 Mandarin
- 170 Mandarin
- 171 Mandarin_scion
- 172 Mandarin_scion_buds
- 173 Mexican_fruit_flies_laying_eggs
- 174 Necrosis
- 175 Planococcus_citri,_adult
- 176 Pomelo,_Citrus_grandis
- 177 Psorosis
- 178 Psorosis
- 179 Psorosis
- 180 Psorosis-A
- 181 Psorosis-A
- 182 Psorosis-A
- 183 Psorosis-A
- 184 Psorosis-A
- 185 Psorosis-B
- 186 Psorosis-B
- 187 Psorosis-B
- 188 Ringspot
- 189 Ringspot
- 190 Ringspot
- 191 Ringspot_psorosis
- 192 Ringspot_Psorosis
- 193 SDV
- 194 SDV
- 195 Seeding_yellows
- 196 Seedling_yellows
- 197 Seedling_yellows
- 198 Seedling_yellows
- 199 Seedling_yellows
- 200 Seedling_yellows
- 201 Spiroplasma_citri
- 202 Spiroplasma_citri
- 203 Spiroplasma_citri
- 204 Spiroplasma_citri
- 205 Stainless-steel_insert
- 206 Stem_pitting_by_tristeza
- 207 Stem_pitting_by_tristeza
- 208 Stem_pitting_by_tristeza
- 209 Stubborn_disease
- 210 Stubborn_disease
- 211 Stubborn_disease
- 212 Stubborn_disease
- 213 Stubborn_disease
- 214 Stubborn_disease
- 215 Stubborn_disease
- 216 Stubborn_disease
- 217 Stubborn_disease
- 218 Stubborn_disease
- 219 Stubborn_disease
- 220 Tatterleaf_effects
- 221 Tatterleaf_virus
- 222 Temperature_effect_on_symptoms
- 223 Tip_browning
- 224 Trioza_erytreae
- 225 Trioza_erytreae
- 226 Tristeza
- 227 Tristeza
- 228 Tristeza_isolate
- 229 Tristeza_isolates
- 230 Tristeza_pitting
- 231 Tristeza_virus
- 232 Tristeza_virus
- 233 Tylenchulus_semipenetrans_female
- 234 Tylenchulus_semipenetrans_female
- 235 Unaspis_citri_on_lime_stems
- 236 Vein-enation_virus
- 237 Vein-enation_virus
- 238 Vein-enation_virus
- 239 Vein-enation_virus
- 240 Viral_effects
- 241 Viral_effects
- 242 Viral_effects
- 243 Xanthomonas_axonopodis_pv._citr
- 244 Xylella_fastidiosa
- 245 Xylella_fastidiosa
- 246 Xylella_fastidiosa
- 247 Xylella_fastidiosa
- 248 Xylella_fastidiosa
- 249 Xylella_fastidiosa
- 250 Xylella_fastidiosa
- 251 Xylella_fastidiosa
- 252 Xylella_fastidiosa
Amorphous_plugs
Amorphous plugs
The dense amorphous plugs as seen in the light microscope (R.H. Briansky)
Bark_cracking
Bark cracking
Mild bark cracking on trifoliate orange rootstock induced by the citrus viroid lla present in "virus" source E-818 (California)
Bark_cracking
Bark cracking
Severe bark cracking on the stem of citron 861-S-1 ubducatir okabt ubicykated wutg CEV
Bark_scaling
Bark scaling
Classic severe bark scaling on trifoliate orange rootstock caused by CEV (California)
Bark_scaling
Bark scaling
Classic severe bark scaling on Rangpur lime rootstock caused by CEV (Brazil) (G. Muller)
Blight
Blight
A typical blight-affected grapefruit tree on the left with a non-affected tree on the right, in Florida
Blight
Blight
A typical blight-affected Pera sweet orange tree on Rangpur lime rootstock in Brazil. Infected tree on the left with a non-infected tree on the right
Blight
Blight
Field tree on the left shows symptoms of blight. This was root-grafted with roots from a five-or six-year-old blight-affected sweet orange tree in the centre. This infected source tree was transplanted between two healthy field trees. The tree on the right is the non-inoculated healthy control
Blight
Blight
Showing the dense amorphous plugs diagnostic for blight as observed in the scanning electron microscope
Browning
Browning
Midvein browning (control on left)
Browning
Browning
Petiole browning and wrinkle (control on right)
Bud-union_abnormality
Bud-union abnormality
Bud-union crease of Valencia on rough lemon rootstock in Florida (S.M. Garnsey)
Bud-union_abnormality
Bud-union abnormality
Bud-union crease of Palmer navel on trifoliate rootstock in South Africa. The condition is transmissible
Bud-union_abnormality
Bud-union abnormality
Bud-union overgrowth of mandarin on Troyer citrange in the Central Valley of California. This condition is attributed to environmental conditions typical for most mandarins and tangelos in the Central Valley. Trees declind in about 15 years
Bud-union_abnormality
Bud-union abnormality
Close-up showing brown line totally around trunk
Bud-union_abnormality
Bud-union abnormality
Transmissible bud-union abnormality of Tomango sweet orange on rough lemon rootstock in South Africa. Cuts made into the bud-union bulge show indentation and severe staining surrounding the union
CEV
CEV
Acorn-shaped fruit of citron induced by CEV (California). Similar acorn-shaped fruit occur on Volkamer lemon
CEV
CEV
Classic severe symptoms of CEV in citron showing severe epinasty of leaves. A few normal control leaves are shown on the left
CEV
CEV
Older trees of Valencia orange on trifoliate rootstock. CEV-infected trees are on the right (All CEV-infected trees show bark cracking on the trifoliate rootstock)
CEV
CEV
The effect of CEV on tree size (California). Five-year-old trees of Valencia orange on Troyer citrange. CEV-infected tree is on the left
CEV
CEV
Yellow blotching on stems of Troyer citrange induced by CEV (Italy). A similar yellow blotching occurs on stems of Rangpur lime
Citrus_blight
Citrus blight:
A sweet orange tree with citrus blight on the right and a healthy tree on the left.
Citrus_blight_(cause_unknown)
Citrus blight (cause unknown):
This tree is showing advanced symptoms of citrus blight. Twig dieback and canopy thinning occur.
Citrus_blight_(cause_unknown)
Citrus blight (cause unknown):
Light yellow amorphous plugs develop in the xylem vessels of blight-affected trees and are diagnostic of citrus blight. Filamentous plugs also occur in citrus, but are not unique to citrus blight.
Citrus_blight_(cause_unknown)
Citrus blight (cause unknown):
A typical blight-affected grapefruit tree on the right with a non-affected tree on the left, in Florida.
Citrus_blight_(cause_unknown)
Citrus blight (cause unknown):
Showing the dense amorphous plugs diagnostic for blight as observed in the scanning electron microscope.
Citrus_blight_(cause_unknown)
Citrus blight (cause unknown):
The dense amorphous plugs as seen in the light microscope.
Citrus_cachexia_viroid
Citrus cachexia viroid:
A window in the trunk of a field tree of Ellendale mandarin showing severe symptoms of gumming on the bark and trunk typical of severe cachexia. Note the areas of gum in the cut-back section (Australia).
Citrus_cachexia_viroid
Citrus cachexia viroid:
The trunk portion of a field tree of Parson's Special mandarin as a rootstock under a grapefruit scion with the bark cut away to show the brown gum-stain. This tree was inoculated with a severe isolate of citrus cachexia viroid (Central California).
Citrus_cachexia_viroid
Citrus cachexia viroid:
Very severe symptom reaction on Parson's Special mandarin after the bark is completely peeled.
Citrus_Cachexia_viroid
Citrus Cachexia viroid
Parson's Special mandarin as a scion budded to rough lemon as the rootstock with a window cut into the bud-union showing severe symptoms in the Parson's Special mandarin. Note that the gumming occurs only in the Parson's Special mandarin and not in the rough lemon rootstock (greenhouse-grown, Riverside, California)
Citrus_Cachexia_viroid
Citrus Cachexia viroid
The trunk portion of a field tree of Parson's Special mandarin as a rootstock under a grapefruit scion with the bark cut away to show the brown gum-stain. This tree was inoculated with a severe isolate of citrus cachexia viroid (Central California)
Citrus_concave_gum
Citrus concave gum:
A narrow oak leaf pattern developed about the midvein in a leaf of Valencia orange. Note the strong interveinal flecking, usually the first symptom observed in leaves on plants inoculated with concave gum virus.
Citrus_concave_gum
Citrus concave gum:
Concavities associated with concave gum diseases in the trunk of a sweet orange tree in the field (Spain).
Citrus_concave_gum
Citrus concave gum:
Concentric gum rings in a cross-section of a branch. This is highly symptomatic for concave gum disease when present with trunk concavities and oak leaf pattern.
Citrus_cristacortis
Citrus cristacortis (cause unknown):
A typical deep pit in the trunk, with corresponding peg in the bark of a Navalina orange tree infected with cristacortis (Spain).
Citrus_cristacortis
Citrus cristacortis (cause unknown):
Cross section of a branch showing both cristacortis and concave gum. The concentric gum rings are associated with concave gum infection, and the pitting in the outer circumference indicates cristacortis.
Citrus_cristacortis
Citrus cristacortis (cause unknown):
Cross section of a branch showing the deep pits caused by cristacortis infection.
Citrus_cristacortis
Citrus cristacortis (cause unknown):
Typical pitting symptom of cristacortis in the trunk of both scion and rootstock. Scion is Clementine mandarin and rootstock is sour orange (Sicily).
Citrus_cristacortis
Citrus cristacortis (cause unknown):
When a section is cut from the bark, the typical pits and pegs are visible in the trunk and inner bark.
Citrus_cristacortis
Citrus cristacortis:
Chlorotic flecks and spots on the leaves of a mandarin tree infected with cristicortis.
Citrus_exocortis_viroid
Citrus exocortis viroid:
Acorn-shaped fruit of citron induced by citrus exocortis viroid (California). Similar acorn-shaped fruit occur in Volkamer lemon
Citrus_exocortis_viroid
Citrus exocortis viroid:
Classic severe bark scaling on trifoliate orange rootstock caused by citrus exocortis viroid (California).
Citrus_exocortis_viroid
Citrus exocortis viroid:
Classic severe bark scaling on Rangpur lime rootstock caused by citrus exocortis viroid (Brazil).
Citrus_exocortis_viroid
Citrus exocortis viroid:
Classic severe symptoms of citrus exocortis viroid in citron showing severe epinasty of leaves. A few normal control leaves are shown on the left.
Citrus_exocortis_viroid
Citrus exocortis viroid:
Scaling occurring on the C-35 citrange rootstock due to presence of citrus exocortis viroid.
Citrus_exocortis_viroid
Citrus exocortis viroid:
Sweet orange trees on C-35 citrange rootstock showing stunting due to citrus exocortis viroid.
Citrus_grandis
Citrus grandis
Citrus_greening
Citrus greening:
A branch on a sweet orange tree that has been infected with citrus greening. Note the small chlorotic leaves that point upright.
Citrus_greening
Citrus greening:
A red mandarin tree affected by the Asian form of citrus greening. The leaves are small, the canopy thins and zinc deficiency symptoms are common.
Citrus_greening
Citrus greening:
A typical greening-affected mandarin tree in the field (New Territories, Hong Kong).
Citrus_greening
Citrus greening:
Abundant greening organisms in the haemolymph of Trioza erytreae.
Citrus_greening
Citrus greening:
Characteristic bumps on the underside of sweet orange leaves caused by the feeding of Trioza erytreae (South Africa).
Citrus_greening
Citrus greening:
Diaphorina citri feeding on a young shoot and leaves of a citrus tree. Note the angular position taken by the insect when feeding (Pakistan).
Citrus_greening
Citrus greening:
Drawing of adults and instars of Diaphorina citri and Trioza erytreae
Citrus_greening
Citrus greening:
Leaves from a red mandarin tree affected by the Asian form of citrus greening.
Citrus_greening
Citrus greening:
The blotchy mottle symptom of citrus greening on a sweet orange leaf. This figure is of African form of greening.
Citrus_greening
Citrus greening:
The yellow vein symptom on a sweet orange tree affected by the Asian form of citrus greening. The yellow vein symptom is helpful to differentiate citrus greening from other chronic tree declines such as citrus blight, tristeza decline, stubborn, and citrus variegated chlorosis.
Citrus_greening
Citrus greening:
Typical greening of fruit. Two normal Valencia oranges surrounded by greening-affected fruit (South Africa). Note the stylar end greening and smaller fruit.
Citrus_impietratura
Citrus impietratura (cause unknown):
Impietratura induced gumming in albedo of a sectioned young grapefruit (Spain).
Citrus_impietratura
Citrus impietratura (cause unknown):
Impietratura induced spotting and gumming in the rind and albedo of Navalina oranges; note the typical green spotting on coloured fruit (Spain).
Citrus_leprosis_rhabdovirus
Citrus leprosis rhabdovirus:
Lesions on citrus fruit
Citrus_leprosis_rhabdovirus
Citrus leprosis rhabdovirus:
Leprosis on the trunk of a tree in Venezuela
Citrus_leprosis_rhabdovirus
Citrus leprosis rhabdovirus:
Leprosis symptoms on sweet orange fruit, young twigs, and leaf. On leaves and twigs, the lesions are first chlorotic, then become necrotic in the center. Extensive lesions on twigs causes dieback. Leaves and fruit commonly abscise on leprosis-infected trees.
Citrus_leprosis_rhabdovirus
Citrus leprosis rhabdovirus:
Specimen of citrus leprosis preserved at the INTA Experiment Station, Concordia, Argentina.
Citrus_psorosis
Citrus psorosis:
Bark scaling in a grapefruit tree caused by Citrus psorosis.
Citrus_psorosis
Citrus psorosis:
Leaf symptoms induced by ringspot psorosis inoculated to seedling of Marsh grapefruit (California).
Citrus_psorosis
Citrus psorosis:
Leaf symptoms of Citrus psorosis occurring on a sweet orange plant.
Citrus_psorosis
Citrus psorosis:
Lesion bark blisters of psorosis-B on a twig and thorn of sweet orange (above) with the non-inoculated control below.
Citrus_psorosis
Citrus psorosis:
Mature ringspot-type leaf symptoms in mature leaves of Valencia orange.
Citrus_psorosis
Citrus psorosis:
Mature ringspot-type leaf symptoms in mature leaves of rough lemon.
Citrus_psorosis
Citrus psorosis:
Necrotic local lesions on Chenopodium quinoa after inoculation with a citrus ringspot strain of Citrus psorosis.
Citrus_psorosis
Citrus psorosis:
Psorosis shock symptoms in inoculated young seedlings of Pineapple sweet orange. The plant on the left is completely shocked. Shock remnants will remain on the plant and do not drop off.
Citrus_psorosis
Citrus psorosis:
Psorosis-B-induced, blister-like lesions on the underside of a sweet orange leaf. Similar lesions may be found on leaves of field trees infected with ringspot.
Citrus_psorosis
Citrus psorosis:
Scaly bark symptoms of psorosis-A on the trunk of a sweet orange in California.
Citrus_psorosis
Citrus psorosis:
Shock symptoms occurring on a Madame Vinous sweet orange indicator plant in the first growth flush after inoculation with buds from field plants infected with Citrus psorosis.
Citrus_psorosis
Citrus psorosis:
Staining of interior wood of a branch of sweet orange infected with psorosis-A. This symptoms is diagnostic for psorosis-A when found on trees showing bark lesions.
Citrus_psorosis
Citrus psorosis:
Symptoms of ringspot on fruit of Clementine mandarin in Spain showing green spotting of fruit. Impietratura may be present.
Citrus_psorosis
Citrus psorosis:
Symptoms of ringspot psorosis on leaves and fruit of Naveline orange in Greece showing indented sunken areas on fruit.
Citrus_psorosis
Citrus psorosis:
The effect of temperature on symptom expression, showing variation in leaf symptoms due to the effect of the above temperature regimes. The leaf on the left is from a plant grown under the cool temperature and the leaf on the right is from a plant grown under the warm temperature regime. Both plants were inoculate with the same inoculum.
Citrus_tatterleaf_capillovirus
Citrus tatterleaf capillovirus
Citrus_tatterleaf_capillovirus
Citrus tatterleaf capillovirus
Citrus_tatterleaf_capillovirus
Citrus tatterleaf capillovirus:
Severe tatterleaf reaction induced by CTLV showing bud-union crease and fluting in the trunk of Troyer citrange rootstock with satsuma orange scion.
Citrus_tatterleaf_capillovirus
Citrus tatterleaf capillovirus:
Breakage and separation of a tatterleaf-infected satsuma scion from the trifoliate rootstock. Specimen at Kuchinotsu, Japan.
Citrus_tatterleaf_capillovirus
Citrus tatterleaf capillovirus:
Symptoms of tatterleaf in leaves of Rusk citrange inoculated with CTLV. Note deformed leaves with spots and blotches.
Citrus_tatterleaf_capillovirus
Citrus tatterleaf capillovirus:
Symptoms of tatterleaf in leaves of citrus excelsa from a seedling inoculated with CTLV. The non-inoculated control leaf is on the left. Note the tattered, irregular-edged leaves giving the disease its name.
Citrus_tatterleaf_capillovirus,
Citrus tatterleaf capillovirus, the virus produces zig zag growth of the stem and distortion of the leaves, as seen on the plant on the left.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Sweet orange tree on sour orange rootstock undergoing tristeza decline
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
In addition to stem pitting of sweet orange, grapefruit, and pummelo scions, some strains of tristeza can also stem pit rootstocks which are normally considered to be tristeza-tolerant. This figure shows stem pitting in rough lemon rootstock.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Quick decline of a sweet orange on sour orange rootstock caused by citrus tristeza virus (Israel). The sudden collapse and death of sweet orange, mandarin or grapefruit on sour orange rootstock is an indication of tristeza.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Vein-clearing symptoms in the leaf of a Mexican lime seedling (right) as viewed from the back of the leaf into direct sunlight. Control on the left.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Mild vein-clearing flecks induced in a leaf of Mexican lime by a mild reacting tristeza isolate.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Vein corking symptoms on leaves of Mexican lime seedling inoculated with a very severe seedling-yellow tristeza isolate.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Seedling-yellows reaction in two Duncan grapefruit seedlings with a non-inoculated control in the centre. Note the severe stunting in the two inoculated seedlings.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Stem pitting in the peeled stem of (b) sour orange.
Citrus_tristeza_closterovirus
Citrus tristeza closterovirus:
Stem pitting on the trunk of a Pera sweet orange tree on Rangpur lime rootstock due to infection with citrus tristeza virus in Brazil.
Citrus_tristeza_virus
Citrus tristeza virus
Quick decline of a sweet orange on sour orange rootstock caused by citrus tristeza virus (Israel). The sudden collapse and death of sweet orange, mandarin or grapefruit on sour orange rootstock is an indication of tristeza
Citrus_variegation_ilarvirus
Citrus variegation ilarvirus:
Symptoms of CIVV on leaves of navel orange from a tree in the field (Spain).
Citrus_variegation_ilarvirus
Citrus variegation ilarvirus:
Symptoms on a citron seedling showing severe epinasty, chlorotic variegation and leaf distortion induced by inoculation with CIVV (California).
Citrus_variegation_ilarvirus
Citrus variegation ilarvirus:
Symptoms on mature leaves of an inoculated Madame Vinous sweet orange seedling showing protuberances and bumps characteristic of infection with CIVV. These symptoms are typical and similar to those induced on mandarins or rough lemon leaves
Citrus_variegation_ilarvirus
Citrus variegation ilarvirus:
Symptoms on leaves of C. spectabilis infected with CIVV.
Citrus_vein_enation/woody_gall
Citrus vein enation/woody gall:
close-up of the trunk of a tree affected by woody gall.
Citrus_vein_enation/woody_gall
Citrus vein enation/woody gall:
Woody gall symptoms associated with the vein enation virus found on the trunk of a rough lemon in the field at the University of California, Riverside.
Citrus_viroid_symptoms
Citrus viroid symptoms in Gynura purpeae. The plant on the left is healthy, the center plant is infected with a mixture of citrus viroids but no citrus exocortis viroid, and the plant on the right is infected with citrus exocortis viroids plus the viroids present in the center plant.
Citrus_viroids
Citrus viroids
Mild symptoms on leaves of 861-S-1 citron. These symptoms,expressed in varying degrees of severiity, are diagnostic for many of the citrus viroids
Citrus_viroids
Citrus viroids
Temperature effect on 861-S-1 citron inoculated with a moderate-reacting mixture of citrus viroids. Plant on the left was grown at relatively cool temperatures; plant on the right was grown at warm temperatures. Note the complete absence of symptoms in the citron branch that was held at the cooler temperature
CIVV
CIVV
Chlorotic lesions on primary leaves of cowpea infected with CIVV
CIVV
CIVV
Necrotic local lesions on primary leaves of cowpea infected with CIVV (S.M. Garnsey)
CIVV
CIVV
Psorosis-like symptoms in young leaves of a rough lemon seedling inoculated with CIVV
CIVV
CIVV
Symptoms of CIVV on leaves of navel orange from a tree in the field (Spain)
CIVV
CIVV
Symptoms on a citron seedling showing severe epinasty, chlorotic variegation and leaf distortion induced by inoculation with CIVV (California)
CIVV
CIVV
Symptoms on leaves of C. spectabilis infected with CIVV (S.M. Garnsey)
CIVV
CIVV
Symptoms on mature leaves of an inoculated Madame Vinous sweet orange seedling showing protuberances and bumps characteristic of infection with CIVV. These symptoms are typical and similar to those induced on mandarins or rough lemon leaves
CIVV
CIVV
Symptoms on secondary growth leaves of red kidney bean infected with CIVV, showing bright vein chlorosis (S.M. Garnsey)
Concave_gum_disease
Concave gum disease
Concavities associated with concave gum diseases in the trunk of a sweet orange tree in the field (Spain)
Concave_gum_disease
Concave gum disease
Concentric gum rings in a cross-section of a branch. This is highly symptomatic for concave gum disease when present with trunk concavities and OLP (R. Vogel)
Concave_gum_disease
Concave gum disease
Concentric gum rings in a cross-section of a small twig. This is also symptomatic for concave gum disease (R. Vogel)
Concave_gum_virus
Concave gum virus
A narrow oak-leaf pattern developed about the midvein in a leaf of Valencia orange. Note the strong interveinal flecking, usually the first symptom observed in leaves on plants inoculated with concave gum virus
Concave_gum_virus
Concave gum virus
Strong oak-leaf patterns in the leaves from a field tree of Valencia orange showing concavities during the spring flush of growth
Cristacortis
Cristacortis
A typical deep pit in the trunk, with corresponding peg in the bark of a Navelina orange tree infected with cristacortis (Spain)
Cristacortis
Cristacortis
Cristacortis pits showing in the outer bark of a tangelo tree (Corsica)
Cristacortis
Cristacortis
Typical pitting symptom of cristacortis in the trunk of both scion and rootstock. Scion is Clementine mandarin and rootstock is sour orange (Sicily)
Cristacortis
Cristacortis
When a section is cut from the bark, the typical pits and pegs are visible in the trunk and inner bark (R. Vogel)
Cristacortis_and_concave_gum_disease
Cristacortis and concave gum disease
Cross-section of a branch showing both cristacortis and concave gum. The concentric gum rings are associated with concave gum i, and the pitting in the outer circumference indicates cristacortis
Cristacortis_infection
Cristacortis infection
Cross-section of a branch showing the deep pits caused by cristacortis infection (R. Vogel)
Cristacortis_infection
Cristacortis infection
Severe pitting induced in a tangelo seedling inoculated with cristacortis-infected budwood (Specimen from R. Vogel)
Cristacortis_infection
Cristacortis infection
Typical oak-leaf pattern in a leaf from a Dweet tangor indicator seedling. This symptom is typically associated with the cristacortis disease
CTLV
CTLV
Bud-union crease of satsuma mandarin on trifoliate rootstock induced by citrus tatterleaf virus (CTLV). Specimen at Kuchinotsu, Japan
CTLV
CTLV
Local lesions in a leaf of red kidney bean mechanically inoculated with CTLV (S.M. Garnsey)
CTLV
CTLV
Severe tatterleaf reaction induced by CTLV showing bud-union crease and fluting in the trunk of Troyer citrange rootstock with satsuma orange scion ( E.C. Calavan)
CTLV
CTLV
Symptoms in secondary growth leaves of Chenopodium Quinoa showing well-distributed spotting, chlorosis and distortion induced by mechanical leaf-rub inoculation with CTLV
CTLV
CTLV
Symptoms of necrotic local lesions in the primary leaves of cowpea induced by mechanical transmission with CTLV from citrus tissue
CTLV
CTLV
Symptoms of tatterleaf in leaves of Citrus excelsa from a seedling inoculated with CTLV. The non-inoculated control leaf is on the left. Note the tattered, irregular-edged leaves giving the disease its name
CTLV
CTLV
Symptoms of tatterleaf in leaves of Rusk citrange inoculated with CTLV. Note deformed leaves with spots and blotches
CTV_isolate
CTV isolate
A mild pit in the peeled stem of a Mexican lime seedling induced by the mild-reacting T-519 CTV isolate
CVV-2
CVV-2
Symptoms of mild isolate CVV-2 on leaves of citron. Symptoms on lemon are quite similar (S.M. Garnsey)
Diaphorina_citri
Diaphorina citri
Diaphorina citri feeding on a young shoot and leaves of a citrus tree. Note the angular position taken by the insect when feeding (Pakistan) (L.C. Cochran)
Diaphorina_citri
Diaphorina citri
Drawing of adults and instars of Diaphorina citri and Trioza erytreae (Source: Catling, 1970)
Drill
Drill
Cordless electric drill making a small hole in trunk
Elsinoe_fawcettii
Elsinoe fawcettii:
Sweet orange scab, caused by Elsinoe australis, on sweet orange in Uruguay.
Female_Mexican_fruit_fly
Female Mexican fruit fly can deposit large numbers of eggs:
up to 40 eggs at a time, 100 or more a day, and about 2,000 over her life span.
Graduated_burette
Graduated burette
Graduated burette hanging from an inside limb
Grapefruit_infected_
Grapefruit infected with green mold.
greasy_spot,_Mycosphaerella
greasy spot, Mycosphaerella citri
Greening_infection
Greening infection
A characteristic greening-affected branch showing leaves with chlorosis, mottle, and yellow midribs and veins (South Africa)
Greening_infection
Greening infection
A typical greening-affected mandarin tree in the field (New Territories, Hong Kong)
Greening_infection
Greening infection
Close-up of a leaf from a greening-affected tree showing vein yellowing and mottle (South Africa)
Greening_infection
Greening infection
Emerging, stunted yellow shoots showing severe chlorosis, typical of greening infection. Yellow shoot or huang-longbing is the name given to this disease in mainland China (Taiwan Province)
Greening_infection
Greening infection
Gracilicute-like bacteria found in cells of a greening-affected citrus leaf. Note trilayered bacterial wall (China) (Phoeo: Ke-Chung)
Greening_infection
Greening infection
Typical greening of fruit. Two normal Valencia oranges surrounded by greening-affected fruit (South Africa). Note the stylar and greening and smaller fruit
Guignardia_citricarpa
Guignardia citricarpa:
Hard spot lesions on citrus fruit in Brazil due to Guignardia citricarpa or citrus black spot. Pycnidia may be present in the center of the lesions.
Gum_pocket
Gum pocket:
Sweet orange tree on Poncirus trifoliate rootstock which is infected with gum pocket. The trees are stunted and nonproductive.
Gumming
Gumming
The appearance of symptoms of gum in the Parson's Special mandarin occurs only at the cut-back joint area, but no symptoms show in the stem above or below the area surrounding the joint
Gumming
Gumming
The first mild gumming symptom usually seen in an exploratory cut into the bud-union area
Gumming_and_Cachexia
Gumming and Cachexia
A window in the trunk of a field tree of Ellendale mandarin showing severe symptoms of gumming on the bark and trunk typical of severe cachexia. Note the areas of gum in the cut-back section (Australia)
Gummy_bark_symptoms
Gummy bark symptoms
A section of bark taken from a gummy bark-infected navel orange near Tarsus, Turkey, showing gum pockets in the bark, and the appearance of these same gum spots (c) when the bark is sliced tangentially
Gummy_bark_symptoms
Gummy bark symptoms
Gummy bark symptoms on Jaffa orange in Syria (R. Vogel)
Gummy_bark_symptoms
Gummy bark symptoms
Gummy bark symptoms in bark of navel orange near Tarsus, Turkey
Hand_drill
Hand drill
Drilling into the tree trunk with a hand drill. The plastic tube shown entering the tree trunk is attached to the graduated cylinder in (a). It is filled with water, and water uptake is measured from the graduated cylinder
Impietratura_infection
Impietratura infection
Circular, puffed, darker green or lighter coloured spots on the rind of a navel orange (Spain). This symptom is indicative of possible impietratura infection
Impietratura_infection
Impietratura infection
Gum showing in the albedo when the rind is sliced somewhat deeper
Impietratura_infection
Impietratura infection
Impietratura-induced gumming in albedo of a sectioned young grapefruit (Spain)
Impietratura_infection
Impietratura infection
Impietrature-induced spotting and gumming in the rind and albedo of Navalina oranges; note the typical green spotting on coloured fruit (Spain)
Impietratura_infection
Impietratura infection
Typical leaf flecking and oak-leaf patterns associated with impietratura disease. Leaves will show this pattern on field trees in the spring flush under cool conditions. Also, this symptom on index plants is used as an indication of the presence or absence of the virus after thermotherapy or shoot-tip grafting
Impietratura_infection
Impietratura infection
When the rind is sliced with a knife, gum is seen in the rind directly beneath the discoloured spots of Figure 84
Injection_procedure
Injection procedure
Injection procedure showing stopwatch and pressure being applied to the plunger of the syringe
Inverse_pitting_on_orange
Inverse pitting on orange
A section of bark cut through the bud-union of a sweet orange on sour orange rootstock showing inverse pitting in the bark of the sour orange. Note the small, closely spaced pits in the inner bark. The sour orange trunk would show corresponding small pegs
Mandarin,_Citrus_reticulata
Mandarin, Citrus reticulata
Mandarin
Mandarin
Symptom reaction on Parson's Special mandarin after the bark is completely peeled -- Mild
Mandarin
Mandarin
Symptom reaction on Parson's Special mandarin after the bark is completely peeled -- Very severe
Mandarin_scion
Mandarin scion
Growth of a Parson's Special mandarin scion as a single shoot or leader. Note careful staking and tying
Mandarin_scion_buds
Mandarin scion buds
Bending the rough lemon seedling just above the scion bud aids in the forcing of the Parson's Special mandarin scion bud
Mexican_fruit_flies_laying_eggs
Mexican fruit flies laying eggs in 'grapefruit' before a test of the reduced-oxygen treatment.
Necrosis
Necrosis
Necrosis of the upper portions of the leaves of a systemically infected sesame plant (Japan) (Photo: M. Miyakawa)
Planococcus_citri,_adult
Planococcus citri, adult
Pomelo,_Citrus_grandis
Pomelo, Citrus grandis
Psorosis
Psorosis
Psorosis shock symptoms in inoculated seedlings of Madame Vinous sweet orange showing the wilt-like drooping of the new shoot. The young leaves will dry up and drop off
Psorosis
Psorosis
Psorosis shock symptoms in inoculated young seedlings of Pineapple sweet orange. The plant on the left is completely shocked. Shock remnants will remain on the plant and do not drop off
Psorosis
Psorosis
Severe scaly bark lesions of psorosis on a nucellar sweet orange tree in Concordia, Argentina
Psorosis-A
Psorosis-A
Scaly bark symptoms of psorosis-A on the trunk of a sweet orange in California
Psorosis-A
Psorosis-A
Staining of interior wood of a branch of sweet orange infected with psorosis-A. This symptom is diagnostic for psorosis-A when found on trees showing bark lesions as in (a)
Psorosis-A
Psorosis-A
The effect of temperature on symptom expression, showing shock symptoms of psorosis-A inoculated sweet orange seedlings grown under relatively cool temperatures of 24 degrees 27 degrees C maximum day (left) compared with no symptoms on plants grown under relatively warm temperatures of 32-38 degrees C maximum day (right) (California)
Psorosis-A
Psorosis-A
Young leaf symptoms in Dweet tangor. A non-inoculated control leaf is on the right
Psorosis-A
Psorosis-A
Young leaf symptoms in Pineapple sweet orange. Mild psorosis-A symptoms in leaves of Pineapple sweet orange with non-inoculated control leaf on the right
Psorosis-B
Psorosis-B
Lesion bark blisters of psorosis-B on a twig and thorn of sweet orange (above) with the non-inoculated control below
Psorosis-B
Psorosis-B
Local lesions on leaves of Chenopodium quinoa induced by mechanical inoculation from ringspot or psorosis-B-infected citrus tissue (control leaves on right)
Psorosis-B
Psorosis-B
Psorosis-B-induced, blister-like lesions on the underside of a sweet orange leaf. Similar lesions may be found on leaves of field trees infected with ringspot
Ringspot
Ringspot
Mature ringspot-type leaf symptoms in mature leaves of Valencia orange (L.J. Klotz)
Ringspot
Ringspot
Mature ringspot-type leaf symptoms in mature leaves of rough lemon
Ringspot
Ringspot
Symptoms of ringspot on fruit of Clementine mandarin in Spain showing green spotting of fruit. Impietratura may be present
Ringspot_psorosis
Ringspot psorosis
Leaf symptoms induced by ringspot psorosis inoculated to seedlings of Marsh grapefruit (California)
Ringspot_Psorosis
Ringspot psorosis
Symptoms of ringspot psorosis on leaves and fruit of Navelina orange in Greece showing indented sunken areas on fruit
SDV
SDV
Graft-inoculated satsuma seedlings inoculated with SDV. Non-inoculated control plant is on the left. Note the smaller-sized plants and spoon-shaped leaves. Photo taken by M. Miyakawa eight weeks after inoculation (Japan)
SDV
SDV
Necrotic local lesions on inoculated cotyledons of a sesame plant inoculated by sap containing SDV (Japan) (M. Miyakawa)
Seeding_yellows
Seeding yellows
A comparison of sour orange and Eureka lemon for their reaction to seven severe seeding-yellows isolates in experiments carried out over a five-year period. Note the similarity of reaction of sour orange and Eureka lemon to all seven isolates. Since sour orange seedlings are highly nucellar and uniform, and uniform nucellar seedlings of lemon are difficult to obtain, the sour orange is the preferred indicator
Seedling_yellows
Seedling yellows
Close-up of seedling-yellows reaction in a sour orange seedling showing smaller pointed leaves and yellows reaction. Control plant on left
Seedling_yellows
Seedling yellows
The time in weeks after inoculation for the first symptoms of seedling yellows to appear in grapefruit, sour orange and Eureka lemon. Graphs are based on seven severe seedling-yellows isolates inoculated into 1200 seedlings and recorded over a five-year period
Seedling_yellows
Seedling yellows
Vein-corking symptoms on leaves of Mexican lime seedlings inoculated with a very severe seedling-yellows tristeza isolate
Seedling_yellows
Seedling-yellows
Reaction in two Duncan grapefruit seedlings with a non-inoculated control in the centre. Note the severe stunting in the two inoculated seedlings
Seedling_yellows
Seedling-yellows
Reaction in two standard sour orange seedlings with a non-inoculated control in the center. Note the stunting and yellows of the two inoculated seedlings
Spiroplasma_citri
Spiroplasma citri:
A stubborn-infected Madame Vinous seedling on the right and a control plant on the left. Note the extreme stunting and chlorosis induced by stubborn infection.
Spiroplasma_citri
Spiroplasma citri:
A stubborn-infected young sweet orange tree in the nursery row (left) showing the small leaves and shorter internodes symptomatic for the disease in warm areas. Compare with the normal nursery tree on the right (California).
Spiroplasma_citri
Spiroplasma citri:
Chlorotic mosaic-like mottle in leaves from a stubborn-infected sweet orange tree. These are typical of leaves from stubborn or greening-affected trees.
Spiroplasma_citri
Spiroplasma citri:
S. citri. The causal organism of stubborn disease as seen in the dark-field microscope. Note the spiral-helical nature of the organism. Motility can been seen in the dark-field microscope.
Stainless-steel_insert
Stainless-steel insert
A stainless-steel insert, which is hammered into the tree and is used as the connecting bridge between the plastic (or rubber) tube and the hole in the trunk
Stem_pitting_by_tristeza
Stem pitting by tristeza
Stem pitting in the peeled stem of sour orange. Normally the sour orange, sweet orange and rought lemon are resistant to stem pitting by many isolates of tristeza. However, this illustrates that there are tristeza isolates
Stem_pitting_by_tristeza
Stem pitting by tristeza
Stem pitting in the peeled stem of sweet orange. Normally the sour orange, sweet orange and rought lemon are resistant to stem pitting by many isolates of tristeza. However, this illustrates that there are tristeza isolates
Stem_pitting_by_tristeza
Stem pitting by tristeza
Stem pitting in the peeled stem of rough lemon. Normally the sour orange, sweet orange and rought lemon are resistant to stem pitting by many isolates of tristeza. However, this illustrates that there are tristeza isolates
Stubborn_disease
Stubborn disease
A seedling with two side grafts showing a single young shoot to be trained as a single leader. The side graft technique is very effective in transmitting stubborn disease
Stubborn_disease
Stubborn disease
A stubborn-infected young sweet orange tree in the nursery row (left) showing the small leaves and shorter internodes symptomatic for the disease in warm areas. Compare with the normal nursery tree on the right (California)
Stubborn_disease
Stubborn disease
A stubborn-infected Madame Vinous seedling on the right and a control plant on the left. Note the extreme stunting and chlorosis induced by stubborn infection
Stubborn_disease
Stubborn disease
Characteristic symptoms associated with infection by S. citri in leaves from a Madame Vinous sweet orange seedling showing pointed tips and translucent chlorotic spotting at the leaf margins and near the tips. These symptoms developed in a greenhouse under warm temperatures and will persist in mature leaves. The control non-inoculated leaf is on the left
Stubborn_disease
Stubborn disease
Chlorotic mosaic-like mottle in leaves from a stubborn-infected sweet orange tree. These are typical of leaves from stubborn or greening-affected trees.
Stubborn_disease
Stubborn disease
S. citri the casual organism of stubborn disease as seen in the dark-field microscope. Note the spiral-helical nature of the organism. Motility can be seen in the dark-field microscope (Calavan)
Stubborn_disease
Stubborn disease
Seed abortion in a Valencia orange in California. The presence of small dark purple-coloured seed (right) is symptomatic for stubborn disease. Such seeds are excellent for culturing of S. citri. Normal seed from a normal fruit is on the left
Stubborn_disease
Stubborn disease
The characteristically stunted and compressed appearance of a stubborn-infected navel orange tree. A non-infected normal tree of the same age is on the left (California)
Stubborn_disease
Stubborn disease
The first symptoms of stubborn in a young shoot of an inoculated Madame Vinous sweet orange seedling. Note the slightly semi-wilted appearance of the young shoot and leaves
Stubborn_disease
Stubborn disease
The stylar-end greening effect on fruit from a stubborn-infected navel orange tree in California. This symptom, induced by the presence of Spiroplasma citri, is indistinguishable from symptoms of fruit on greeninng-infected trees caused by Asian or South African greening (Figure 15)
Stubborn_disease
Stubborn disease
Three stubborn-infected Madame Vinous plants on the left compared with three control plants on the right. Note the smaller leaves and compressed growth in the infected plants. Plants were inoculated by side grafting and held in a warm greenhouse
Tatterleaf_effects
Tatterleaf effects
Breakage and separation of a tatterleaf-infected satsuma scion from its trifoliate rootstock. Specimen at Kuchinotsu, Japan
Tatterleaf_virus
Tatterleaf virus:
Chlorotic lesions and leaf distortion on rusk citrange leaves infected with tatterleaf virus, the healthy leaves are on the right.
Temperature_effect_on_symptoms
Temperature effects on symptoms
The effect of temperature on symptom expression, showing variation in leaf symptoms due to the effect of the above temperature regimes. The leaf on the left is from a plant grown under the cool temperature and the leaf on the right is from a plant grown under the warm temperature regime. Both plants were inoculated with the same inoculum
Tip_browning
Tip browning (control on left)
Trioza_erytreae
Trioza erytreae
Abundant greening organisms in the haemolymph of Trioza erytreae (J. Moll)
Trioza_erytreae
Trioza_erytreae
Characteristic bumps on the underside of sweet orange leaves caused by the feeding of Trioza erytreae (South Africa)
Tristeza
Tristeza
Stem pitting in the peeled stem of grapefruit. Normally the sour orange, sweet orange and rought lemon are resistant to stem pitting by many isolates of tristeza. However, this illustrates that there are tristeza isolates
Tristeza
Tristeza
Vein-clearing symptoms in the leaf of a Mexican lime seedling (right) as viewed from the back of the leaf into direct sunlight. Control on the left
Tristeza_isolate
Tristeza isolate
Mild vein-clearing flecks induced in a leaf of Mexican lime by a mild-reacting tristeza isolate
Tristeza_isolates
Tristeza isolates
The time in weeks after inoculation for the first vein-clearing symptoms to appear in leaves of Mexican lime seedlings. Graphs are based on eight tristeza isolates inoculated into 355 seedlings recorded over a seven-year period. Most isolates induced vein clearing within eight weeks
Tristeza_pitting
Tristeza pitting
Severe pitting in the peeled stems of Mexican lime seedlings. Most tristeza isolates will induce this type of pitting
Tristeza_virus
Tristeza virus
Cupping on leaves of Mexican limes inoculated with tristeza virus. Note also vein clearing
Tristeza_virus
Tristeza virus
Symptoms due to tristeza virus, viewed on the underside of a leaf of sweet orange by reflected light. Symptoms are the dark-gree-to-black broken lines in the leaf veins. These are the same areas that show up as translucent when viewed from the underside of the leaf in transmitted direct sunlight
Tylenchulus_semipenetrans_female
Tylenchulus semipenetrans female swollen with eggs on root of citrus
Tylenchulus_semipenetrans_female
Tylenchulus semipenetrans female swollen with eggs on root of citrus
Unaspis_citri_on_lime_stems
Unaspis citri on lime stems
Vein-enation_virus
Vein-enation virus
Vein enations on the underside of leaves of a Mexican lime seedling which had been graft-inoculated with vein-enation virus. A non-inoculated leaf is on the bottom
Vein-enation_virus
Vein-enation virus
Vein enations on the underside of leaves of a sour orange seedling which had been graft-inoculated with the vein-enation virus
Vein-enation_virus
Vein-enation virus
Woody galls in an older seedling of rough lemon. This seedling has been puncture-inoculated when small by Dr J.M. Wallace using needles
Vein-enation_virus
Vein-enation virus
Woody-gall symptoms associated with the vein-enation virus found on the trunk of a rough lemon in the field at the University of California, Riverside
Viral_effects
Viral effects
A branch from an infected field tree of satsuma mandarin showing typical spoon-or boat-shaped leaves (Japan)
Viral_effects
Viral effects
A satsuma dwarf virus-infected tree in the field (right) showing typical stunting and dwarfing (Japan)
Viral_effects
Viral effects
Symptoms on leaves from a satsuma seedling induced by graft-inoculation with buds from an infected tree in the field. Typical spoon- or boat-shaped leaves with occasional crinkle are seen (Japan)
Xanthomonas_axonopodis_pv._citr
Xanthomonas axonopodis pv. citri on citrus leaf, Citrus sinensis
Xylella_fastidiosa
Xylella fastidiosa:
A high magnification of a Xylella fastidiosa bacterium in the xylem vessel of a CVC infected tree. Note the triple layer membrane and ridged nature of the cell wall.
Xylella_fastidiosa
Xylella fastidiosa:
A higher magnification of a thin section across a xylem vessel from a tree infected with CVC showing the Xylella fastidiosa bacterium.
Xylella_fastidiosa
Xylella fastidiosa:
An example of the raised gummy lesions which form on the underside of the leaves (bottom leaf) as well as the chlorosis and necrotic areas on the upper surface of the leaves (upper leaves).
Xylella_fastidiosa
Xylella fastidiosa:
Fruit from CVC-infected trees are small, contain less juice, ripen earlier, and have a hard rind. The few large fruit on the top of this box are from a healthy tree, the rest of the fruit are from a CVC infected tree.
Xylella_fastidiosa
Xylella fastidiosa:
In parts of Argentina, a similar disease is called picoseta. This is the leaf symptoms on a sweet orange tree from Misiones, Argentina.
Xylella_fastidiosa
Xylella fastidiosa:
Often one sector of a tree will show the symptoms first. Zinc deficiency-like chlorosis is commonly the first symptom of CVC to show on a sector, followed by reduced fruit size.
Xylella_fastidiosa
Xylella fastidiosa:
The leaf symptoms of CVC begin with the interveinal chlorosis followed by the appearance of necrotic spots with a gummy raised lesion directly below on the underside of the leaf. It is not uncommon for young leaves to be asymptomatic.
Xylella_fastidiosa
Xylella fastidiosa:
The Xylella fastidiosa bacterium which causes CVC often reaches high concentrations in xylem vessels.
Xylella_fastidiosa
Xylella fastidiosa:
This slide illustrates the nature of the interveinal chlorosis on the leaves from CVC infected trees.