CÁCH PHÒNG VÀ TRỊ BỆNH THÁN THƯ TRÊN HOA SEN Trên lá: Vết bệnh ban đầu là những đốm tròn nhỏ hoặc không có hình dạng nhất định, màu nâu nhạt dưới lá, sau chuyển sang màu nâu sậm có viền đỏ hặc quầng vàng lan rộng xung quanh. Vết bệnh điển hình và đặc […]
Rose Midge On Friday, August 23, 1996 I visited a rose nursery in Petaluma, Sonoma County, California that was heavily infested with the rose midge, Dasineura rhodophaga (Coquillett) [Diptera: Cecidomyiidae]. Nearly 100% of the new growth in a section of the field grown roses was affected. The infestation was first detected in early August by […]
GRASSHOPPERS AND RELATED INSECTS ON ROSES
EARWINIGS
SCALE INSECTS ON ROSE PLANT
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 […]
