Control methods of common diseases and insect pests of rose

Rose flowers are beautiful, varied and fragrant, and the four seasons are often blooming, especially a wide variety of varieties, easy to breed and cultivate, known as the "queen of flowers", is one of the top ten famous flowers in China, but rose diseases and insect pests often cause poor growth, or even death, seriously affecting the ornamental value, let's take a look at the common rose pest control methods!

Rose powdery mildew

[symptoms] chlorotic macula appeared at the initial stage of the diseased leaves, then enlarged and covered with raw white powder, reverse curling, wrinkling, thickening, slightly inflated petiole and tender shoots after infection, reverse bending, and flower posture deformity after bud infection. In severe cases, the leaves are withered and yellow and the plants are weak.

[occurrence regularity] the pathogen overwinters on buds, leaves and branches and spreads by the wind. The optimum onset temperature was 17-25 ℃, and the peak period was from May to June and from September to October. The disease is easy to occur when there is too much nitrogen fertilizer or too little potassium fertilizer in the soil.

[prevention method] resistant varieties were selected for ①. ② fertilize reasonably and avoid nitrogen fertilizer. ③ clears and burns diseased leaves in early spring. ④ was moderately pruned to keep the plant ventilated and transparent. Spraying triamcinolone acetonide and Baiyuqing before and after the onset of ⑤.

Rose black spot

[symptoms] Rose leaves, pedicels and twigs can all suffer from brown seeds to brown spots at the initial stage, then expand and become black or dark brown, often surrounded by yellow halos, and in severe cases, the middle and lower leaves of the whole plant all fall off, and the branches die.

[occurrence regularity] the pathogen overwintered in diseased branches and leaves or fallen leaves, spread by wind and rain, was the most serious after the end of summer, the disease of high temperature and drought spread slowly, and weak plants were easy to occur.

[control methods] the diseased leaves were removed in time by ①, and the diseased plants were heavily pruned in winter. ② is often pruned during the growing season to maintain good ventilation. ③ can be controlled by chlorothalonil, carbendazim, Dysen zinc, methyl topiramate and other agents.

Rose leaf blight

The symptoms occurred in the leaves of rose, the yellow-green needle spots appeared on the leaves at the initial stage, and the lesions expanded in round or irregular shape at the later stage, with purple edges, continuous patches after expansion, obvious disease key boundaries, small black spots in the later stage, and burning edges of the diseased leaves.

[occurrence regularity] the pathogen overwintered in diseased leaves or soil and spread old leaves, weak branches, rainy seasons and extensive management.

[prevention and treatment methods] ① cleared and destroyed the diseased leaves in time. ② selected disease-resistant varieties, reasonable close planting, and strengthened maintenance. ③ was sprayed with 3-degree stone-sulfur mixture in dormancy season. Spraying chlorothalonil and other agents before the onset of ④. In the early stage of ⑤, carbendazim and other agents were sprayed for prevention and treatment.

Rose root cancer

[symptoms] nodules of different sizes and shapes appeared in the roots and stems of the rose, with poor plant growth, short branches and leaves, withered yellow leaves, early fall, small or non-flowering flowers.

[occurrence regularity] germs survive in the soil and spread by water and tools. At the beginning, the tumor is small and soft, white, and then gradually increases, turning dark brown, rough and cracked on the surface, hard and Lignification.

[prevention and control methods] planting in the open field should not be repeated as far as possible, improve the level of grafting, change the method of grafting, reduce the wound and avoid infection.

Rose mosaic disease

The main symptoms are flowers and leaves, some with annular spots or oak leaf patterns, and some with chlorotic spots, yellow veins or dwarfing.

[occurrence regularity] viral diseases, diseased plants as breeding materials, juice contact and piercing pests can spread. Strong light and drought in summer are beneficial to the development and expansion of disease.

[control methods] ① avoids using diseased plants as breeding materials. ② found that the diseased plants were removed and destroyed in time. Disease-resistant varieties or tissue culture seedlings were selected for ③. Attention should be paid to the control of aphids and other transmission media in the growing season of ④. In the early stage of ⑤, aminooligosaccharides were sprayed to inhibit the spread of the virus.