MAIZE INBREED LINES RESISTANCE TO FUSARIUM EAR

ROT

Branimir Šimić - The Agricultural Institute Osijek,31 000 Osijek, CROATIA

Jasenka Ćosić - Vlatka Rozman - Anita Liška University of J.J. Strossmayer in Osijek,

Faculty of Agriculture in Osijek, CROATIA

Introduction

• Vital importance of maize as agricultural crop and market competitiveness among hybrids seed breeders set up high standards in new genotypes creation

• New maize hybrids - high genetic potential for fertility and resistance to the major disease agents and pests

• Fusarium ear rot is one of the most important diseases in all the major

maize breeding areas in the world

• Maize ear infection results in lower maize yield, and poorer quality and accumulation of mycotoxins in grain - risk for human and animal health

• Most frequent isolated Fusarium species on maize grain: Fusarium verticillioidesF. subglutinans andF. graminearum

• Ways of spreading maize ear infection:

silkear stalkdamage made by insects

• Infection, development and intensity of disease are influenced by environmental factors, genotype sensitivity and resistance, and pathogenesis of Fusarium spp. and their mutual interaction

• Stress in the period of vegetation affects plant’s vigour - disorders in physiological processes and increase sensitivity to the agents of the disease

Objective of the study:• determine differences in sensitivity and

resistance of inbreed maize lines grown on two different soil types to Fusarium ear rot

Materials and Methods

• Six inbreed maize lines of FAO 400 and one line of FAO 300 (OS 138-9)• Two locations and two soil types (Kutjevo; pseudogley and Nova

Gradiška; amphigley)• 3-year trial (2001-2003)• Four repetitions following split-plot method

(major plot measured 300m2 ; (15x20m)• Standard fertilization was made:

Urea 200 kg NPK (7:20:30) 200 kg m-2 (ploughed in) KAN 150 kg m-2 in nutrition while cultivating

• 120 plants of each genotype were examined measuring intensity of infection in percentage of maize ear infection

• Results were processed by Statistica for Windows v. 6.0• Significant differences among the treatments were determined by

ANOVA and LSD test

Results and Discussion

Table 1 Percentage of maize ears infected with Fusarium spp. regarding locations and years (%)

Line 2001 2002 2003

Pseudoglay Amphyglay Pseudoglay Amphyglay Pseudoglay Amphyglay

OS 36-16 60.9 38.1 74.4 49.5 58.0 43.9

OS 2-48 56.3 48.3 68.7 56.2 64.6 47.1

OS 84-44 61.9 44.5 66.1 53.3 60.3 49.2

OS 138-9 64.6 51.4 69.0 58.3 59.4 50.5

OS 84-49 60.3 43.1 66.2 34.3 51.2 49.4

OS 89-9 30.9 24.6 36.7 39.3 34.7 33.2

OS 86-39 38.2 21.1 34.4 23.1 21.9 19.6

• Differences in infection intensity with Fusarium spp. could be explained by the differences in plant nutrition (phosphorus)

• Insufficient nutrition with phosphorus affects physiological process → development of pathogenic organisms

Increasing of the maize grain yield by:• increasing effect of photosynthesis

• advancing metabolism of carbohydrates and water transport

• improving reproduction and grain forming phosphorus

xx

Line _x

Year _x

Location _x

OS 36-16 54.16 2001 45.96 Pseudoglay 54.19

OS 2-48 56.87 2002 52.11 Amphigley 41.81

OS 84-44 55.76 2003 45.94

OS 138-9 58.87

OS 84-49 50.78

OS 89-9 33.23

OS 86-39 26.38LSD 0,05 1.39 0.74 0.74

LSD 0,01 1.88 0.97 0.98

• Statistically significant differences were also determined in inbreed lines sensitive to Fusarium ear rot

• The most tolerant inbreed lines: OS 89-9 and OS 86-39, regardless of the year or location examined

Table 2. Average occurrence (%) of Fusarium ear rot depending on inbreed line, year and location examined

ConclusionConclusion

• Percentage of the infected maize ears on both locations during 3-year trials was on average 48.3 %

• The lowest infection was observed on inbreed line OS 89-9 (33.2%) and inbreed line OS 86-39 (26.4%)

• The highest infection was observed on inbreed line OS 138-9 (58.9%)

• The source of high inbreed lines tolerance appeared to be crucial for further maize hybrid selection

The most tolerant inbreed line:The most tolerant inbreed line: (OS 86-39) FAO 400(OS 86-39) FAO 400

Corresponding author:e-mail address: branimir.simic@poljinos.hr (Branimir Šimić)

University of J.J. Strossmayer in Osijek, Faculty of Agriculture in Osijek,

CROATIA

The Agricultural Institute Osijek31 000 Osijek, CROATIA