Category: Cây Cảnh – Bonsai

APHIDS

ROSE ROSETTE ON ROSE PLANT CAUSAL ORGANISM: This “disease” appears to be vectored by a blister mite but the causal agent has not been identified. Some plant pathologists think that it is a virus while others, incuding entomologists, think that the disease is the result of the blister mite feeding. Mosaic is probably the most […]

ROSE SPRING DWARF DISEASE CAUSAL ORGANISM: A virus is suspected in causing this disease. SYMPTOMS: Rose mosaic usually appears in spring as a distortion of growing tips or expanding leaves. Later the leaves can appear to be wavy and have yellow lightening patterns, oak leaf patterns or simply gold to yellow veins. Plants infected with […]

ROSE MOSAIC ON ROSE PLANT CAUSAL ORGANISM: Prunus Necrotic Ringspot Virus: Mosaic is probably the most commonly found virus on roses but many other virus diseases also exist. While mosaic is transmitted by propagation other viruses can be transmitted by pollen, insect feeding or simply by mechanical contact. Symptoms of virus are usually dramatic manifestations of […]

BACTERIAL CROWN GALL ON ROSE PLANT CAUSAL ORGANISM: Agrobacterium spp: This is really the only serious bacterial disease of Rose. The bacteria is found world wide wherever roses are grown and is especially severe in loose sandy or sandy loam soils. SYMPTOMS: On roses the symptoms of overgrowths can occur at the crown, bud union or […]

RUST ON ROSE PLANT CAUSAL ORGANISM: Phragmidium spp: The rust of rose is one of the most commonly found and easily identified diseases of rose. Severe outbreaks occur where cool temperatures and high moisture are found during the prime growing season. Where foliage is heavy, the first symptoms usually are found close to the ground and […]

BOTRYTIS BLIGHT ON ROSE PLANT CAUSAL ORGANISM: Botrytis cinerea: Botrytis blight is common in all parts of the world. This fungus is not a specific pathogen and can take advantage of many situations to produce a blight or rot condition on many hosts. It is an opportunist on cut or pruned rose canes and will infect […]

 ANTHRACNOSE ON ROSE PLANT CAUSAL ORGANISM: Sphaceloma rosarum: Not much is known about this disease, however, it can be severe under cool moist spring conditions. Wild rose, climbers and ramblers seem most susceptible but hybrid tea and bush roses also get the disease. SYMPTOMS: Initially leaf spots are about .5 cm diam and black, which makes […]

BLACKSPOT ON ROSE PLANT CAUSAL ORGANISM: Diplocarpon rosae: This disease may also be called leaf spot, leaf blotch, star sooty mold and several other names. It is the most important disease of outdoor roses on a world wide basis. The fungus has probably been widely distributed with the cultivated rose and no really complete resistance is […]

BỆNH ĐỐM LÁ PHYLLOSTICTA TRÊN HOA HỒNG (phyllosticta leaf spot dis ease)   Bệnh đốm lá Phyllosticta phổ biến hơn bệnh đốm đen và thán thư đối với cây hồng, bệnh đốm lá thường bẳt đầu xuất hiện và gây hại phố biến ở phần chóp lá hoặc rìa lá hồng, sau đó vết bệnh sẽ lan […]