Edible Mushroom Cultivation Techniques and Main Pest and Disease Control Methods for Summer Flowers
I. Occurrence Situation
Black spot: occurs on rose and pothos (Epipremnum aureum), with an average incidence rate of 15.2% on rose leaves and 6.67% on pothos leaves.
Anthracnose: occurs on hydrangea, chrysanthemum and Calathea makoyana, with Calathea makoyana being more severely affected, showing an average leaf incidence rate of 31.5% and up to 50% in severe cases; hydrangea leaves show an average incidence rate of 8.2% and up to 15.2%; chrysanthemum leaves show an average incidence rate of 9.62% and up to 20%.
American leafminer (Liriomyza sativae): a survey of peony showed an average leaf damage rate of 13.16%, up to 33%; 4.39 live larvae per 100 leaves.
Mealybugs: a survey of broadleaf lady palm (Rhapis excelsa) showed 10.16 live insects per 100 leaves, up to 26.
Thrips: severe occurrence on small-leaved fig (Ficus microcarpa). Average leaf damage rate 20-30%, about 30 live insects per 100 leaves, up to over 100 in severe cases.
Tobacco cutworm (Spodoptera litura): a survey of rose showed an average damage rate of 2.9%, with 62 live larvae per 100 flowers.
II. Occurrence Trend Analysis
(1) Flower cultivation involves diverse varieties, scattered planting areas and varying planting periods, making the occurrence periods of pests and diseases relatively complex.
(2) From April to June, affected by severe thunderstorm weather, diseases occurred more severely, leaving a certain amount of pathogenic bacteria.
(3) According to the forecast of the Guangzhou International Professional Meteorological Observatory: the general weather trend for Guangzhou in the post-flood season after 2005 is: total rainfall from July to September slightly above normal; Cold Dew wind (hanlu feng) in a relatively light year; 3-4 tropical cyclones affecting Guangzhou, concentrated in July to September. Therefore, black spot and anthracnose are expected to occur at moderate to severe levels, while American leafminer, mealybugs, thrips and tobacco cutworm are expected to occur at moderate levels.
III. Control Recommendations
(1) Agricultural control measures:
1. Promptly remove diseased plants and leaves affected by black spot and anthracnose and destroy them in a centralized manner; manage fertilizer and water reasonably to reduce the spread of pathogenic bacteria.
2. Pay attention to ventilation in greenhouses, control the temperature and humidity inside, and inhibit the occurrence and spread of diseases.
(2) Chemical control:
Black spot: spray with 25% myclobutanil at 8000 times dilution or 10% difenoconazole at 1500 times dilution, spraying 2-3 times consecutively at intervals of 7-10 days.
Anthracnose: spray with 80% Daconil M-45 wettable powder at 600 times dilution or 25% prochloraz at 500-1000 times dilution. Apply once every 7-10 days, for 2-3 consecutive applications.
American leafminer: choose 1.8% abamectin at 1000 times dilution or 40% lücaibao at 1000 times dilution for spraying.
Mealybugs: choose 40% Supracide emulsifiable concentrate or 40% sujieke emulsifiable concentrate at 1000-1500 times dilution for spraying.
Thrips: spray with 10% yashijing at 1000 times dilution or 40% sujieke at 1000-1500 times dilution.
Tobacco cutworm: spray with Chongwen No.1 at 1000-1500 times dilution or 20% miman at 1500 times dilution in the evening.