Flower crops are prone to pests and diseases after drought
After drought, flower crops or legume crops suffer from insufficient soil moisture, poor root growth, and difficulty in fully and effectively absorbing water and nutrients. The above-ground parts of the plants tend to show weakened growth and yellowing, and in severe cases, the lower branches and leaves, or even the entire plant, may wilt due to water shortage and dehydration. Under conditions of insufficient soil moisture, fertilizers in the soil are not easily dissolved or absorbed by plants, leading to excessive accumulation and residue in the soil, which can subsequently cause salt damage. Cell growth is affected by uneven water supply, the physiological state of the plant body is poor, and it is highly susceptible to infection by various pathogens. At the same time, under relatively dry and hot climatic conditions, the development and breeding of certain pests are often favored, and they attack the plants, ultimately creating a dire situation in which the effects of drought and pest and disease damage coexist.
Usually in dry and hot environments, the common pests harmful to crops are aphids, spider mites, beet armyworms, thrips, whiteflies and similar pests, while the common diseases harmful to crops are viral diseases, powdery mildew, sooty mold, damping-off, Fusarium wilt and nutrient deficiency disorders (physiological diseases). Therefore, while actively combating drought and reducing disaster impacts, integrated pest and disease management for flower crops or legume crops should be carried out in response to the pests and diseases commonly seen in dry and hot environments. In addition, easily soluble fertilizer types should be selected and applied in small amounts at the appropriate time.
Preventive and control technical measures can be carried out according to the characteristics and patterns of the occurrence and damage of these diseases and pests, following the routine control methods for aphids, spider mites, beet armyworms, thrips, whiteflies, powdery mildew, damping-off and Fusarium wilt. Pesticides needed for pest and disease prevention and control should be prepared in advance so as to timely and effectively control the impact of pest and disease damage.
The overall principle is: do a good job of cleaning and sanitation inside and around the greenhouse, and promptly remove weeds and carry out insecticidal and sterilization work inside the greenhouse. At the same time, do a good job of routine repair and maintenance of the greenhouse film, doors and windows, and insect-proof nets to ensure or enhance the greenhouse's physical insect-blocking and insect-preventing performance. Patrol the greenhouse carefully every day, observe closely, and do a good job of regular chemical insect prevention, insect killing and plant protection work; once individual or a small number of diseased plants are found, they should be pulled out immediately, and comprehensive pesticide control and application should be carried out at the same time. For pesticide control of pests, attention should be paid to the principle that aphids, spider mites, thrips and whiteflies all have piercing-sucking mouthparts and cause damage by sucking plant sap; stomach-poison pesticides should be selected for control. Beet armyworm has chewing mouthparts and causes damage by feeding on various parts of the plant. Contact-killing pesticides should be selected for control.
There are certain differences in the specific pesticides used for pest and disease control, listed as follows:
Common pesticides for controlling damping-off
Zineb, thiram, daojiaoqing, tianan, isoprothiolane, edifenphos, rice blast net, quintozene, mepronil, thiophanate-methyl (thiophanate-methyl), chlorothalonil, salicylanilide, fenaminosulf (dexon), flutolanil (Moncut), propiconazole (Tilt), nuarimol (Trimidal), iprodione (Rovral), carbendazim, hymexazol (Tachigaren), dimethachlon, thiram mixture (Tuzet), carboxin-thiram (Vitavax), captan, diniconazole, metham-sodium, propamocarb-oxadixyl, dazomet (Basamid), jinggangmycin ….
Common pesticides for controlling Fusarium wilt
Thiophanate-methyl (thiophanate-methyl), hymexazol (Tachigaren), metham-sodium, carbendazim, iprodione (Rovral), difenoconazole (Score), dazomet (Basamid), benomyl, captan, propamocarb-oxadixyl ….
Common pesticides for controlling powdery mildew
Thiophanate-methyl (thiophanate-methyl), triadimefon.
For the control of viral diseases and sooty mold, aphids, thrips, whiteflies and spider mites should be controlled first, because they are usually the transmission vectors of viral diseases.
Common pesticides for controlling beet armyworm:
Malathion, dichlorvos, trichlorfon, phoxim, chlorpyrifos (Lorsban), nongdile, methomyl, cypermethrin, fenvalerate, nongmengte, chlorfluazuron, flufenoxuron, diflubenzuron No. 1, diflubenzuron No. 3, kuai shaling, emamectin benzoate, abamectin, BT emulsion, Bacillus thuringiensis ….
Common pesticides for controlling thrips:
Caixi, methomyl, phoxim, quinalphos, carbaryl (Sevin), acetamiprid, chlorpyrifos (Lorsban), nongdile, omethoate, dichlorvos, fipronil (Convido), fipronil (Regent), deltamethrin, beta-cypermethrin, fenvalerate, derris extract, azadirachtin, abamectin ….
Common pesticides for controlling spider mites:
Azocyclotin, dicofol, amitraz, flufenoxuron, hexythiazox, propargite, pyridaben, fenbutatin oxide, bromopropylate ….
Common pesticides for controlling aphids and whiteflies:
Abamectin, imidacloprid, acetamiprid, pirimicarb, methomyl, fenpropathrin, acephate, dimethoate, omethoate, dichlorvos, trichlorfon, compound liuyangmycin …