Plant Problem Investigating West FL

Category: Education

Presentation Description

How to detect and investigate problems with tomatoes.


Presentation Transcript

Troubling Shooting Tomato Problems:

Troubling Shooting Tomato Problems

Irregular Ripening:

Irregular Ripening Caused by feeding of nymphs of Silverleaf Whitefly ( Bemisia argentifolii ) Can occur with as few as 4 nymphs per terminal leaf Can be controlled if nymphs are controlled

Irregular ripening of tomato from silverleaf whitefly:

Irregular ripening of tomato from silverleaf whitefly

PowerPoint Presentation:

Normal color Pale color from silverleaf whitefly

Thrips Injury and Tomato Spotted Wilt Virus:

Thrips Injury and Tomato Spotted Wilt Virus


Catfacing Something happens during the formation of the flower that results in the blossom end of the fruit not forming properly


Causes Temperatures - Cold Pruning - Heavy Varieties - Jointed vs. jointless Thrips feeding Exogenous supplies of hormones


Zippering Not sure of exact cause Some consider mild type of catface Others feel due to blossom sticking to side of fruit and causing deformation

Blossom End Rot and Ca Related Disorders:

Blossom End Rot and Ca Related Disorders Cause: Localized deficiency in the developing fruit or young leaves

Factors Affecting BER:

Factors Affecting BER Soil Ca content Nitrogen rates Nitrogen source Concentration of K and Mg Salinity Humidity Soil moisture Degree of pruning (tomatoes)

Supplemental Ca :

Supplemental Ca Soil application when soil test shows need, will help If soil test shows adequate Ca and have BER, may have other problems Foliar application of Ca to control BER is worthless


Control Usually water related

Graywall (blotchy ripening):

Graywall (blotchy ripening) Dark brown to black necrotic tissue usually in the walls of tomato fruit but at times may be in center area also

Cause – not entirely known:

Cause – not entirely known Varietal differences More of a problem during cool, cloudy or short day periods High N can increase High K can decrease

Internal White Tissue:

Internal White Tissue Usually occurs when temperatures are high during ripening period Are differences between varieties, very firm varieties are more prone Adequate K can reduce More of problem with vine-ripe and upick operations


Cracking Have radial and concentric cracking Are variety differences Excessive water can increase More of problem when picking vine ripes

Fruit cracking:

Fruit cracking

Rain Check:

Rain Check Disruption of the cuticle Not exactly sure why happens Are variety differences Can occur even with a dew


Puffiness Characterized by reduction or absence of seed Open locules are present Can occur when high or low temperatures occur during bloom Are varieties that are resistant


Sunscald Sub lethal – tissue is yellow and hard, tissue temperatures above 86 o F results in yellow pigment formation but not red Lethal – tissue is white, sunken and dead, tissue temperatures above 104 o F result in tissue death Encourage good foliage coverage to reduce problem

Pox and Fleck:

Pox and Fleck Pox is characterized by small cuticle disruptions at random on the fruit Fleck also know as Gold Fleck is characterized by small dark green spots that turn gold as fruit ripens Are varietal differences Is genetic defect that manifests it self under certain environmental

Zebra Stripe:

Zebra Stripe Variety related Genetic problem whose symptoms show up under certain environmental conditions May be linked to pox and fleck

Early Blight:

Early Blight

Early blight on tomato stems:

Early blight on tomato stems

PowerPoint Presentation:

Target Spot

PowerPoint Presentation:

4 Symptoms on leaves (2, and 3) is a good indicator; symptoms on fruit (4) is a definitive confirmation for Target spot .

Late blight:

Late blight

PowerPoint Presentation:

Bacterial wilt caused by Ralstonia solanacearum Bacterial streaming from cut stem of a wilted plant is a definitive confirmation of Bacterial wilt

PowerPoint Presentation:

Bacterial spot caused by Xanthomonas campestris pv. vesicatoria

Leaf symptoms of Fusarium wilt:

Leaf symptoms of Fusarium wilt

Clogging of vascular system:

Clogging of vascular system

PowerPoint Presentation:

There is only one fungal disease that is known to cause a white fungal mycelial mat like growth on the collar region of the plant and the adjacent soil: Southern blight caused by Sclerotium rolfsii

PowerPoint Presentation:

Definitive confirmation of Southern blight is the mustard like structure known as sclerotia which is white, light brown, or dark brown in color. At later stages, you may only see sclerotia and not the mycelium

PowerPoint Presentation:

If is not southern blight blight, may be it is Sclerotinia blight caused by Sclerotinia sclerotiorum Stem blight may be due to Sclerotinia sclerotiorum

PowerPoint Presentation:

You may see white fungal growth on the blighted stem in case of Sclerotinia blight

PowerPoint Presentation:

Definitive confirmation of Sclerotinia blight: black fungal structures called sclerotia can be seen inside the blighted stem with the white fungal growth.

PowerPoint Presentation:

Fusarium wilt caused by F. oxysporum f.sp . lycopersici, or Verticillium wilt caused by V. dahliae , and V. albo-atrum . All these three diseases can cause vascular discoloration. Wilting, and yellowing of the leaves in FL may be most likely due to Fusarium wilt. Culturing in the lab required for confirmation.

PowerPoint Presentation:

No Disease Management options 1 Bacterial wilt Grafted plants with hybrid rootstocks 2 Southern blight Field fumigation 3 Sclerotinia blight Field fumigation 4 Fusarium wilt (Races 1,2 and 3 are known) Resistant varieties Field fumigation Grafting with resistant rootstocks (increasingly used in organic and greenhouse production) 5 Verticillium wilt (Races 1 and 2 known) Resistant varieties Field fumigation Grafting with resistant rootstocks 6 Tomato Spotted Wilt (TSW) Resistant varieties Reflective mulches Thrips pesticide management Kaolin SAR inducer Production in fields with no history of the disease is an important management option for soil-borne organisms causing wilt symptoms. Tomato Spot Wilt is not a soil-borne issue.

PowerPoint Presentation:

Interveinal chlorosis, Invard curling of the leaf, distorted leaf, cracking of the fruit is due to little leaf (cause not known)


Cutworms Active at night. Cut off plants at ground level.

Tomato Hornworm:

Tomato Hornworm Very large worm

Fully grown hornworms:

Fully grown hornworms


Leafminers Adults are flies

Trails of miners:

Trails of miners

Various stages of aphids:

Various stages of aphids

Spider Mites:

Spider Mites Spider mites damage to eggplant Spider mite webbing

Spider mites are not insects. Very difficult to control:

Spider mites are not insects. Very difficult to control

Damage from piercing, sucking insects (stinkbug):

Damage from piercing, sucking insects ( stinkbug)

Corn earworm, one of several species of ear-feeding worms:

Corn earworm, one of several species of ear-feeding worms

Tomato fruitworm:

Tomato fruitworm

authorStream Live Help