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What could be wrong with my roses? (pest & disease identification)

Weedkiller deformation, likely due to evaporation from near by spraying.
Note the unaffected sprouting below which means the plant will replenish itself. 

 Seirous weedkiller deformation, in many cases the plant keeps on making deformed growth and has to be replaced. Sucker compared to basal shoot (water shoot), note the light green thornless sucker which needs to be removed and the redish basal shoot which is beneficial.
fertiliser burn due to granules sticking to wet leaves, not serious, plant will outgrow  Fertiliser burn due to overdose of fertiliser applied, note blackening from bottom stems. Daily watering can save the plant in some cases. Close up of fertiliser burn
Planted too deep, rose struggles as root level is too low. Level should be at 3 cm above bud union. Planted too deep, note the inferior root formation. The dying back of a stub on on a healthy plant is not a problem.
Sunburn - main cause is defoliation of a stem. Slowed down sap flow causes sap in stem to boil which burns cells in stem. Spraying with a double dose of Dithane WG and increasing watering curative. Stem kanker Die back never goes below a vigorous side stem.
Phyllody is not a disease, simply a natural deformation often experienced when night and day temperatures fluctuate. Another type of Phyllody, normal new growth will sprout underneath. Petal sun burn, mostly a varietal occurence
Petal fleck virus on 'Flamingo', does not spread to other plants only by propagating from infected plant A weak neck on Sweet Surrender, varietal occurence Roses irrigated during minus degrees, no damage occurs
A knobbly bud union on a 30 year old plant Crown gall, infectiuos killer disease. Infected plant should be burnt and contaminated soil area disinfected with basamid.  Close up of crown gall caused by bacterial (agro bacteria tomephacius) infection (cancerous growth)
Yellowing of leaves caused by under watering Standing water caused plant to die, bad drainage suffocates roots
A great variation of rose leaves, varietal occurence,  even number of pinnae from leaves on one stem can vary.   Black spot - most common fungus disease, caused by long periods of wet leaves. Regular, preventative spraying is essential.  Black spot spreads from lower leaves.
Rust occurs in very wet and moist climate. Curative spraying with plant vax advisable. Powdery Mildew, common fungus disease. Preventative and or curative spraying with is essential. Powdery Mildew always starts on the upper leaves and around the peduncle
Downy Mildew is a serious fungus disease and can appear on the leaves, in the stem and on the bud. Long spells of wet weather and high humidity are its cause. Curative spraying is essential. Bothrytis is a fungus similar to mould on fruit. Large soft petalled blooms are more susceptible and rot from the inside instead of developing and opening. In extreme wet weather conditions Bothryits can spread to entire plant.
Mosaic Virus, does not spread to other plants only by propagating from infected plant. More a nuisance then a threat. All types of chlorosis, indicates a defficiency of various nutritious minerals in the soil. Close up of chlorosis.
Iron defficiency Magnesium defficiency Overdose of fertiliser, not serious, plant will outgrow 
Heat stress, caused by extreme hot and dry weather Wind damage - simply by strong winds rubbing leaves and stems against each other Sunburn - plant reviving itself after increased watering
Boll worm, larvae from moth eggs laid on sepals of tight bud. Stem borer wasp drills 5cm deep hole into stem to lay eggs. Not a serious problem.   Mealy bug breading on the underside of leaf, sucking out chlorophyll.
Termites ring bark the plant. Note the callus around the main stem where bark has been chewed away. Pernicious scale, infestation mainly caused by unhappy roots and compacted soil. Pernicious scale, infestation mainly caused by unhappy roots and compacted soil.
Soil weavel, ringbarks plant under the soil which stops sap flow and caused plant to die. Sooty mould , a mould that grows on aphid's sugary excrement. Aphids sucking sap from sepal and bud. Ladybird feasting on aphids. 
A beatiful insect that doesn't do harm to roses. Chafer beetle, laces leaves. Active only at night and burrows itself into soil during day. Laced leaves after chafer beetle activity.
Chafer beetle chews holes in every leaf.  Wilt / Thorn beetle Wilt beetle damage
Fruit beetles devour fragrant blooms Fruit beetles devour fragrant blooms CMR (Cape Mounted Rifle) Beetle devour fragrant blooms
CMR beetles anethetised by Ludwig's Insect Spray + Red spider mite infection. Mites suck from underside of leaf. Red Spider Mites and eggs visible on under side of leaf.
Serious spider mite infection. Web spun around leaf and activity high. Serious spider mite infection. Active mites already in bloom. Thrips in leaf causes deformation on new growth.
Close up of adult thrips. Thrip damage on bloom. Thrips can be seen crawling amongst petals. Thrip damage on bloom. Thrips can be seen crawling amongst petals.