Identification of Pathogenic Fusarium spp. Causing Maize Ear Rot and Potential Mycotoxin Production in China

Abstract

Ear rot is a serious disease that affects maize yield and grain quality worldwide. The mycotoxins are often hazardous to humans and livestock. In samples collected in China between 2009 and 2014, Fusarium verticillioides and F. graminearum species complex were the dominant fungi causing ear rot. According to the TEF-1α gene sequence, F. graminearum species complex in China included three independent species: F. graminearum, F. meridionale, and F. boothii. The key gene FUM1 responsible for the biosynthesis of fumonisin was detected in all 82 F. verticillioides isolates. Among these, 57 isolates mainly produced fumonisin B1, ranging from 2.52 to 18,416.44 µg/g for each gram of dry hyphal weight, in vitro. Three different toxigenic chemotypes were detected among 78 F. graminearum species complex: 15-ADON, NIV and 15-ADON+NIV. Sixty and 16 isolates represented the 15-ADON and NIV chemotypes, respectively; two isolates carried both 15-ADON and NIV-producing segments. All the isolates carrying NIV-specific segment were F. meridionale. The in vitro production of 15-ADON, 3-ADON, DON, and ZEN varied from 5.43 to 81,539.49; 6.04 to 19,590.61; 13.35 to 19,795.33; and 1.77 to 430.24 µg/g of dry hyphal weight, respectively. Altogether, our present data demonstrate potential main mycotoxin production of dominant pathogenic Fusarium in China.

Quantitative Disease Resistance: Dissection and Adoption in Maize

“…In China, northern leaf blight (NLB, caused by the fungus Setosphaeria turcica) and head smut (caused by Sphacelotheca reiliana) are two major diseases in northeast corn regions (Bai et al, 1994;Jiang et al, 2012); stalk rots (mainly caused by Pythium inflatum Matthews and Fusarium graminearum), MRDD, southern leaf blight (SLB, caused by the fungus Cochliobolus heterostrophus), and southern rust (caused by the fungus Puccinia polysora) are major concerns in Yellow-Huai-Hai River plain corn regions (Lu et al, 1995;Zhao et al, 2012bZhao et al, , 2013Tao et al, 2013b;Wang et al, 2014); banded leaf and sheath blight (BLSB, caused by Rhizoctonia solani), gray leaf spot (GLS, caused by the fungi Cercospora zeae-maydis and Cercospora zeina), and ear rot (mainly caused by Fusarium verticillioides and Fusarium graminearum) are the most important diseases in southwest corn regions (Chen et al, 2013;Liu and Xu, 2013;Duan et al, 2016); head smut, common smut (caused by Ustilago maydis), and common rust (caused by Puccinia sorghi) are major prevalent diseases in the northwest corn belt (Wang et al, 2006(Wang et al, , 2014. In the United States in 2015, the prominent corn diseases in the northern states included NLB, anthracnose stalk rot (caused by Colletotrichum graminicola), GLS, Goss's wilt, southern rust, Fusarium (F. verticillioides) and Gibberella (F. graminearum) stalk rot; and in the southern states, Fusarium stalk rot, nematodes, GLS, southern rust, seedling blights, root rot, and NLB (Mueller et al, 2016).…”

Antifungal Activity of Essential Oil ofEucalyptus camaldulensisDehnh. against SelectedFusariumspp.

“…Fusarium spp. cause a wide range of plant diseases such as wilts and cankers in many horticultural, field, and ornamental plants; root rots, stalk rots, and ear and kernel rot in maize [5, 6]. Maize ear and kernel rot caused by Fusarium spp.…”

“…Maize ear and kernel rot caused by Fusarium spp. is one of the most important diseases that affect maize production resulting in decrease in grain yield and quality due to contamination with various mycotoxins such as fumonisins, deoxynivalenol, nivalenol, and zearalenone [6, 7]. …”

Nutritional Composition and Phytochemical, Antioxidative, and Antifungal Activities ofPergularia tomentosaL.

“…is the largest expansion in “Tuberculariaceae” family. It causes wilts and cankers, stalk rots, leaf wilting, maize horticultural, field, and ornamental plants and affects tomato and many cucurbits [11, 12]. …”