Study On Shanxi Malus Asiatica Rust And Construction Of Disease Identification Model Of Leaves

Malus asiatica is malus of Rosaceae,Fruit of Malus asiatica also known as Anhuahong,Shaguo.It is edible,nutritious,and medicinal.Play an important role in the field of medicinal materials and people’s lives.Malus asiatica originated in the Yellow River Basin of China.In recent years,the planting area of Northwest,Inner Mongolia and Northeast China has been expanding.The serious occurrence of rust has become an important factor restricting the development of Malus asiatica industry.Serious economic losses to production.In order to understand the occurrence and development characteristics of Malus asiatica rust symptoms,Micromorphology of pathogen,and the occurrence law of diseases.Screening Efficient Fungicides and Construction of Leaf Disease Recognition Model Based on Image Processing Technology.In this paper,the Malus asiatica rust on the campus of Shanxi Agricultural University was taken as the research object.From 2019 to 2021,the occurrence and ending time of symptoms in different periods cypress of Rust in mangrove and its surrounding areas were continuously observed and recorded.Combined with meteorological data,the occurrence regularity of Malus asiaticarust in local area was clarified.Observation and description of pathogen morphology in different stages of Malus asiatica rust by paraffin section and microscopic observation.Screening of High Efficient Fungicides for Malus asiatica Rust by Spraying.Provide theoretical basis for prevention and control in production.ollection of Images of Leaves of Malus asiatica Rust at Different Stages.Construction of Leaf Disease Identification Model Using Image Processing Technology.Nondestructive automatic identification of plant diseases and scientific evaluation of disease severity based on diseased leaves.Put forward scientific and reasonable plan for plant disease prevention and control and forecast the occurrence and development of plant diseases in the future.The main research results are as follows :1.As early as 12 February(2020-2021),Neoaspore horns parasitized on cypress trees were observed.with temperature increasing.Rapid increase in the number of winter spores.By February 25,it basically reached the peak,and the number tended to be stable.Average temperature is 4.8℃,maximum10.5℃,minimum 1.3 ℃ no rainfall during this period.The formation of winter spore angle is related to temperature but not rainfall.Spore Angle Water Absorbent Gelation in Rain.It takes about 15℃ of ten-day average temperature and more than 15 mm of maximum rainfall,or more than 25 mm of ten-day rainfall to produce basidiospores.Leaves of Malus asiatica appear disease spots as early as May 3,2019,disease spots continued to grow until June 20.Spots appeared on 12 May 2020 and continued until 27 June.The earliest symptom of ’ trichome ’(Rust device)appeared on 20 June in 2019.The earliest symptom of ’ trichome ’(Rust device)on Malus asiatica leaves in 2020.About 40 days from the onset of lesions to ’ hairy ’(Rust device)Speculated basidiospores spread locally from April 20 to June 20.The peak period is from late May to mid-June,and from late April to mid-May is the key period for the disease control.2.Long-term outdoor observation of winter spores on cypress.There are many forms of winter spores on cypress.The shape of winter spore angle changes with time.The angle of winter spores is between 3mm and 20 mm.The angle of ungelatinized winter spores was bark color.Colloidized winter spore horns are yellow and brown.When the rain is sufficient,the colloid is bright yellow and the dead spores are black.Spore twins,pale yellowish brown,elliptic,terminal with transparent pedicel,size 25 μm ~ 50 μm x20 μm ~ 22 μm.Ovoid basidiospores,13μm ~ 16μm × 7.5μm ~ 9μm in size.Before the rupture of the sporozoites,the shape of the sporozoites is round,the aperture of the mature sporozoites is cracked,the shape of the sporozoites is flask,the size is 80μm ~ 200μm × 50μm ~ 120μm.Sex spores,unicellular,spindle-shaped,6.7 μm × 3 μm in size.The rust is shuttle-shaped,700μm ~ 900μm × 200μm ~ 240μm in size.Rust spore unit cell,spherical or polygonal,20 μm ~ 25 μm × 14 μm ~ 24 μm in size.3.Pesticide test of red rust in Taigu District of Shanxi Province.The results showed that all five fungicides had certain control effects on Malus asiatica rust.Among them,the better ones were 30 %trifloxystrobin.tebuconazole EC(2000 times),250 g / L propiconazole EC(3000 times),and 10 %difenoconazole water dispersible granules(2000 times)with the last control effects of 100 %,95.56 %,and 100 %,respectively.Second,the last control effect of 80 % mancozeb WP(1000 times)and thiophanate methyl WP(800 times)were 71.11 % and 70.67 % respectively.t is suggested that spraying at the peak period of basidiospore transmission from late April to late May every year for three consecutive times every 10 days can play a better control effect on Malus asiatica rust.4.Automatic segmentation of mosaic rust leaf image using K-means clustering algorithm.Estimation of disease severity by pixel statistics and automatic classification of disease severity based on image processing.Can achieve accurate recognition.The accuracy rate of judging the severity of the diseased leaves was 92.5 %.