Evaluation of Advanced GEM Lines for Multiple Insect Resistance and Fumonisin Concentration

Martin BohnCrop Sciences

University of Illinois

Objectives

Evaluate GEM lines for their resistance against WCR as well as first and second generation ECB. Evaluate GEM lines for their resistance against Fusarium species.

Determine the association between insect resistance and fumonisin concentration in GEM germplasm.

Objectives

Study the genetic basis of insect resistance in maize against both insect species by diallel crosses and testcrosses, and

Initiate a recurrent selection program aimed to develop new maize lines with improved multiple insect resistant (MIR).

Approach

Maize

GEM-Pop. (25%)

WCR

ECB

GEM-Pop. (100%)

Materials and Methods

“Population” 15 Entries“Inbred” 20 Entries

Location: Urbana

Design: α – lattice, 4 replications

Plot size: Population – 4 row plotsInbreds - 2 row plots

Row size: 1.50m × 0.75m10-12 plants hand planted

WCR eval.: Trap crop

ECB eval.: 1ECB – 180 eggs / plant2ECB – 180 eggs / plant

Materials and Methods: WCR

Node-Injury Scale (0.00 – 3.00) (Oleson and Tollefson, Iowa State Uni.)

1.50

No. of full nodes eaten

% of a node eaten

3.000.00

Materials and Methods: ECB

Leaf Damage Rating

1 = no visible leaf feeding9 = long lesions on most

leaves

Stalk Damage Ratings

1 = no stalk breakage9 = stalk breakage beneath

the ear

Number of Larvae

Source: D. Barry

Source: T. Magg

Results: Populations

DKXL212:N11a01UR10001:N1708bUR10001:N1702CH05015:N1204DKB844:S1612NGSDCRW1(S2)C4-15-2S2(S1)FS8A(T):N1804FS8A(S):S0907CASH:N1410AR17056:N2025AR16026:S1719AR13035:S11b04AR17056:S1216UR13085:N0204AR16026:N1210

MAX

MEAN

1.74

1.40

MIN 0.881.00

1.80

0.60

Root Damage Ratings (0.00 – 3.00)

http://www.ent.iastate.edu/pest/rootworm/nodeinjury/nodeinjury.html

LSD(5%) = 0.99

Results: Inbreds

http://www.ent.iastate.edu/pest/rootworm/nodeinjury/nodeinjury.html

1.08

LSD(5%) = 0.74

Root Damage Ratings(0.00 – 3.00)

CUBA117:S1520-153AR17056:N2025-728B64CUBA117:S1520-182AR17056:N2025-#5AR17056:N2025-522CUBA117:S1520-52CUBA117:S1520-41CUBA117:S1520-156AR17056:N2025-546AR17056:N2025-508AR17056:N2025-#2AR17056:N2025-532B37Mo17AR17056:N2025-#4NGSDCRW1(S2)C4-15AR17056:N2025-#1AR17056:N2025-#3B73

0.50

1.50

2.00

0.56

1.73MAX

MEAN

MIN

Results: ECB

Mean SE Min Max

LDR 3.97 0.68 3.18 5.25SDR1 2.34 0.82 1.82 2.96SDR2 3.96 0.64 3.04 5.441ECB 2.51 0.84 1.85 3.522ECB 3.46 0.78 2.45 4.54

Evaluation of inbreds derived from GEM populations (25% exotic) for various ECB resistance traits.

SE = Standard error

Results: ECB

Mean SE Min Max

LDR 4.73 0.23 2.73 7.62SDR1 4.18 0.60 2.38 6.54SDR2 2.90 0.71 2.14 4.501ECB 4.10 0.46 2.79 7.262ECB 3.41 0.65 2.33 5.06

Evaluation of GEM populations (25% exotic) for various ECB resistance traits.

SE = Standard error

Summary

Results confirm: Populations AR17056:N2025 and CUBA117:S1520 are possible sources of WCR resistance.

Four inbreds derived from populations AR17056:N2025 (2) and CUBA117:S1520 (2) showed significantly (P < 0.05) lower root damage ratings than the resistant check.

Significant (P < 0.01) differences between entries were found for leaf damage ratings. Some inbreds and populations showed intermediate levels of resistance against the first generation ECB.

Differences between entries for stalk damage ratings and number of larvae were not significant.

Activities in 2004

Repeat experiment!

Screen more GEM germplasm!

Conduct diallel study!

Initiate recurrent selection programs!

Acknowledgements

Mike Gray

Sue Ratcliffe

Kevin SteffeyBrad EngelRicardo Fonseca

And to the “rest” of crew: