Flint®, a new dimension in fungal disease control Flint®, a new ...

Figure A: How a mesostemic fungicide worksFungicide depositsStrong activity on theplant surfaceAbsorption by the waxy layerof the cuticle (rainfastness,fungicide barrier againstfungal attacks, reservoir forcontinuous uptake andredistribution)Penetration into planttissue (continuouspenetration of a.s. forlong-lasting control)Cuticle (upper surface)EpidemisMesophyllVascular bundleCross section of a leafCuticle (lower surface)Redistribution & redepositionacross the surface of morecomplete protection (vapourmovement & surface moisture)Translaminar movement andactivity (protection on bothsides of the leaf)control within the crop canopy.Re-distribution and re-depositionof the chemical also take place insurface moisture.The active substance also penetratesinto plant tissues and showstranslaminar activity, ensuring thatboth leaf surfaces are protectedfrom disease infection. However,there is little or no transport withinthe vascular system of the plant.Significant amounts of chemicalcontinue to penetrate the planttissue from the surface deposit, withno dilution because of the lack ofsystemic transport of the fungicide.The result is sustainable, high-leveldisease control.The mesostemic power, therefore,confers the qualities Prevention,Persistence and Protection indisease control, as illustrated below.Together, these comprise the three“P”s concept. Flint truly representsa major advance in chemical diseasecontrol.Three “P”s of mesostemic power of Flint123Attracts to and actson plant surfaceHigh affinity withwaxy layerTranslaminar activity,redistribution by superficialvapour movement,then re-depositionTotal disease managementprogramme...Flint 50 WG should be used withinan integral disease managementprogramme which includes otherfungicides possessing a differentmode of action. This will ensurehighly-effective disease control andprovide a sustainable strategy forthe management of fungicideresistance.Due to its outstanding activity andplant compatibility, there is greatflexibility in the timing of applicationof Flint 50 WG within diseasemanagement programmes such asthose we have developed forcucumber, chilli, rice, and chrysanthemum.Guidelines on the use ofFlint 50 WG in these crops areoutlined below....in cucumberCucumber, a popular vegetablegrown in the lowlands, is seededdirectly on raised beds. The cropgrows for about three months.A well-developed leaf canopy isformed within a month of seedingand flowering begins. Nutrientdemand becomes critical at thisstage. The most important disease isdowny mildew (PseudoperonosporaPrevention(prevents disease establishment)Persistence(long-lasting control,rainfastness)Protection(total protection)cubensis), and, to a lesser extent,powdery mildew (Sphaerothecafuliginea). Both diseases affect theleaves. A normal fungicide sprayprogramme consists of 12 sprays atseven day intervals, beginning atabout seven to ten days aftergermination.Flint 50 WG provides good controlof downy mildew, especially when itis tank-mixed with a contactfungicide such as Antracol ® 70 WP(propineb).Flint 50 WG mixed with Antracol70 WP at 250 g + 1500 g/ha shouldbe applied in alternation with otherfungicides possessing a differentmode of action, but with specificactivity against the same diseases,especially downy mildew. Sprayingshould begin during the floweringand early harvesting periods. Notmore than three sprays of the Flint50 WG + Antracol tank-mixcombination should be applied percrop season....in chilliTraditionally, chilli has been grownas a smallholder’s crop, but it is nowalso widely planted on a commercialscale in the lowlands. Amongthe serious fungal disease problemsare anthracnose fruit rot (Colletotrichumcapsici) and Choanephorashoot blight (Choanephoracucurbitarum). These two diseasesdevelop and spread rapidly duringthe wetter periods of the year,attacking the plants particularly inthe fruit-bearing stages.Mature, ripe fruits are susceptibleto fruit rot. Sunken lesions firstappear on the fruit surface, followedby the development of blackacervuli arranged in concentricrings.Shoot blight includes wet rot on thegrowing shoots, stems, fruit stalksand fruits of the plant. Duringextended warm, wet weather,Courier 1/200217