![](\"http:\/\/www.agrolink.com.br\/upload\/imagens-resizes\/dc94d5bde77044ceabbdbe1bcec78a9e_858x483.jpg\")
<\/p>\n<\/p>\n
Wetter winters increase attention to speckled leaf spot in crops. wheat<\/a>Caused primarily by the fungus Parastagonospora nodorum, the disease finds favorable conditions when there is more humidity, cold nights, and prolonged periods of wet leaves. In these situations, it can advance from the lower leaves to the upper parts of the plant and reach the ear of corn.\n<\/p>\n The progression of the disease reduces the green area of the leaves, compromising photosynthesis and grain filling. When it reaches the ears, it can also harm grain formation and affect the industrial quality of the wheat. The concern increases mainly between July and October, a period when the crop goes through important stages of development. In years with more frequent rainfall, strategies adopted in drier seasons may not offer the same protection, especially when they involve longer intervals between applications or programs focused primarily on rusts.<\/p>\n Rain favors new cycles of the disease.<\/strong><\/p>\n The fungus can remain in infected wheat crop residues from the previous season. With rain and prolonged periods of dew, spore production and release occur, which can be spread by water splashes and the combination of wind and rain. Infection is favored when leaves remain wet for several hours and temperatures are mild, typically between 15 and 25 \u00b0C.<\/p>\n After lesions appear, the fungus can produce new spores and initiate other infections. Therefore, rainier years allow for a greater number of disease cycles within the same growing season, increasing pressure on the crop, especially between tillering and grain filling. Symptoms appear as small or medium-sized lesions on the leaves, generally with an angular or elliptical shape and color ranging from light brown to dark brown.<\/p>\n The top leaves need attention.<\/strong><\/p>\n In drier winters, the speckled leaf spot may remain concentrated on the lower leaves and have less impact. The scenario changes when rainfall is frequent. With longer periods of leaf wetness, the disease can advance to the upper part of the plant. The loss of green area on the flag leaf and nearby leaves reduces the capacity for photosynthesis precisely during a phase that is important for grain formation.\n<\/p>\n The flag leaf deserves special attention in management because it plays an important role in photosynthesis during grain filling. Therefore, keeping this leaf protected is one of the key points highlighted in planning applications during periods of higher disease pressure.<\/p>\n\n<\/div>\n\n<\/div>\n\n<\/div>\n\n<\/div>\n