Brazil is the world’s biggest producer of sugarcane (Saccharum spp. hybrids). Pokkah boeng is an important fungal disease in this crop caused by members of the Fusarium fujikuroi species complex (FFSC) and characterized by deformation of the aerial part of the plant and stem rot. While the occurrence of symptoms has been reported in plantations in Brazil, no official reports of the disease exist. In this study, species of the FFSC were identified that are associated with sugarcane plants with symptoms of pokkah boeng in Brazil. This was achieved using two‐loci molecular phylogeny, sexual compatibility and analysis of morphological markers. The ability of strains to cause disease in plants of sugarcane, maize, sorghum and millet was also evaluated. The 39 isolates studied were identified as F. sacchari, F. proliferatum and another, still unknown, phylogenetic lineage that is sister to F. andiyazi. Crossing field isolates of F. sacchari and F. proliferatum with their respective tester strains produced fertile perithecia and viable ascospores. All three species induced symptoms of pokkah boeng on inoculated sugarcane plants and caused stem rot in maize, sorghum and millet. Symptoms on sugarcane are chlorosis and necrosis of leaves, punctured lesions, twisted leaves, reduction of the total leaf area, death of the top of the plant and stalk rot. The findings confirmed the aetiology of the disease in Brazil, generated basic knowledge for the development of strategies for diagnosis and monitoring of the disease and support breeding programmes for selecting resistant germplasm.

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Toxigenic fungi that infect corn grains are among the major problems in Brazil as they are associated with toxicological implications for both humans and animals. Mechanical-physical methods have been used to separate contaminated grains in lots of corn kernels based on the symptoms caused by fungi. The objective of this study was to assess whether the presence or the type of symptoms were associated with fungal incidence and total fumonisin levels in corn kernel samples from the field. Kernels of two hybrids were separated visually into three groups: 1) asymptomatic or symptomatic exhibiting 2) kernel rot or 3) kernel streak symptoms. A high frequency of Fusarium spp. was observed in asymptomatic (69.5%) and kernel rot (69.9%). Stenocarpella sp. and Penicillium sp. were found in kernel rot (16.0%) and kernel streak (44.1%), respectively. High fumonisin levels (7.24 μg.g-1), above the maximum tolerated limit, were detected only in kernel rot. No association between fumonisin levels and the frequency of Fusarium spp. in kernels was found.

The objective of this work was to evaluate the effect on the physiological and biochemical aspects of garlic submitted to water deficit, knowing that the popular garlic Allium sativum L. is a culture known worldwide for its medicinal, culinary and ecological properties of agricultural pests. were constituted with water condition of 100; 75; 50 and 25% of pot capacity (CP). Three bulbs were planted per pot (5 L) containing Plantmax® substrate, irrigated every two days, according to pot capacity. The chlorophyll index was evaluated during the first and last week of greenhouse treatments. At 45 days after the treatments, the garlic plants were harvested to evaluate the physiological and biochemical parameters. Garlic plants showed to be sensitive to water deficit, resulting in lower leaf length and fresh biomass. Water stress induced the activity of the APX enzyme in the leaves and of the POD in the roots, as well as increase of proteins in the bulbilhos as biochemical mechanisms of adaptation.

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