Disease and Nematode Control on Corn. A. K. Hagan Department of Entomology and Plant Pathology

Transcription

1 Disease and Nematode Control on Corn A. K. Hagan Department of Entomology and Plant Pathology

2 Control of A. flavus and reduction of aflatoxin in corn Aflatoxin, which is a mycotoxin produced by the fungus Aspergillus flavus and A. parasiticus, greatly reduces the cash value of corn. Significant health threat to pets, livestock, and poultry. Weather and insect pests enhance risk of contamination.

3 Afla-Guard in Corn Apply at a rate of 20 lbs/acre, once per growing season. Optimum results are obtained if application is made when abundant moisture is available, such as soon after a rain or irrigation. Apply by air at the first sign of corn tasseling and before active silking.

4 Genuity VT Triple Pro Bt Specific activity against corn earworm, fall armyworm, and European corn borer on ears. Better than YGCB trait. Looking at combination of Genuity VT Triple Pro with Aflaguard to help minimize risk of aflatoxin in corn.

5 Aflatoxin contamination in corn as influence by presence of Bt traits Family HX 1 YGCB YGCB HX 1 VT3 HX 1

6 Diseases on Corn Southern rust Southern corn leaf blight Northern corn leaf blight Gray leaf spot Southern rust Southern corn leaf blight on P31G65 Gray leaf spot Northern corn leaf blight

7 Fungicide Timing for Corn Uniform field with high yield potential. Wet weather patterns from tasseling through soft dough. Apply at blister or milk stage and repeat as needed 7 to 14 days later. Apply at first sign of disease.

8 Corn Fungicides Dithane M-45/Pencozeb 1.2 fl oz or 1.5 lb/a (GLS, SCLB) Tilt, PropiMax, Bumper 2-4 fl oz/a (SCLB) 4 fl oz/a (Rust, GLS) Stratego 250EC fl oz (Rust) fl oz/a (SCLB GLS, ESP) Quilt 7-14 fl oz/a (NCLB, SCLB) fl oz (Rust, GLS, ESP) Quilt Xcel fl oz Quadris fl oz/a (Rust) fl oz/a (SCLB, NCLB, GLS, A) Headline 2.09E 6 12 fl oz/a (Rust, SCLB, NCLB, GLS, A) Headline AMP fl oz/a (Rust, SCLB, NCLB, A) Orius/Monsoon/Tebuzol/ TebuStar 4-6 fl oz/a (Rust, SCLB, NCLB, GLS) = New Product

9 Yield response to corn P33M53 to fungicide inputs Fungicide and Rate/A Tilt 3.6E 4 fl oz Quadris 15.4 fl oz Bravo Ultrex 1.4 lb Stratego 250SE 10 fl oz Non-sprayed Control Yield b ab c a b

10 Yield response of March-planted Pioneer 33M53 and Pioneer 31N30 to fungicide inputs at GCREC Fungicide Test Weight lb/bu Yield bu/a Tilt 3.6E 4 fl oz Quilt 15.4 fl oz Headline 2.09E 9 fl oz Stratego 10 fl oz Folicur 3.6F 6 fl oz Non-treated Control Fungicides applied at GS R2 and GS R4.

11 Impact of timing and number of Heritage applications on the severity of Southern rust and on yield and test weight of double crop Pioneer 31P42 corn Growth Stage No. applications Primary disease Rust rating Test weight Yield lb/a VT-R1-R2-R4 4 rust 2.3 d 61.1 a a R1-R2-R4 3 rust 2.6 d 60.7 ab a R2-R4 2 rust 4.4 c 60.8 a b R4 1 rust 6.2 b 60.4 b 95.8 c Non-Treated 0 rust 7.6 a 59.2 c 88.7 c

12 Root Knot Nematode in Corn Corn-Peanut-Corn Corn-Corn-Corn-Corn Cotton root knot nematode (Meloidogyne incognita race 3) was not considered a major pest in corn. While reproduction of this nematode was reported on corn inbred lines and then commercial varieties, no associated yield loss was described.

13 Corn Yield regressed against Cotton Root Knot Nematode Larvae Numbers-2005 Corn Yield bu/a Corn yield loss due to cotton root knot nematode 80 Corn Yield bu/a Number of J2 Cotton Root Knot Larvae Regression of Corn Yield against Cotton Root Knot Larvae Numbers Based on a previous years post-harvest nematode counts, saw a 3.8 to 11.4% yield loss for every 100 root knot larvae in 100 cc soil sample Numbers of J2 Cotton Root Knot Larvae

14 Impact of cropping sequence on corn yield PBU 2009 A Yield bu/a B CD BC D Study site has a high population of cotton-root knot nematode.

15 Impact of cropping sequence on corn yield GCREC 2009 A A A A Yield bu/a B

16 Corn Nematicides Product Rate Mocap 15G Lock n Load ¾ to 1 lb per 1000 linear ft on 12 to 15 in band lb/a on 36 in row lb/a on 30 in row Counter 15G Lock n Load 6 to 8 oz per 1000 linear ft on 7 in band or in-furrow. 8.7 lb/a Will also control corn root worm and wireworm.

17 Corn yield response to Counter 15G PBU Rotation Study Treatment Counter 15G 6.5 lb/a Yield bu/a 170 A Non-treated Control 154 B Net Yield Gain with Counter 15G + 16 bu/a

18 Impact of Counter 15G insecticide on numbers of cotton root knot, test weight and yield of corn BARU 2009 Location Treatment Root knot juvenile count Test Weight lb/bu Yield bu/a Soil Insecticide Counter 15G 6.5 lb/a 50 a 56.4 a a Non-treated control 44 a 56.4 a b Test site cropped to corn for third consecutive year.

19 Corn yield response to Counter 15G GCREC Rotation Study Treatment Counter 15G 6.5 lb/a Yield bu/a 119 a Non-treated Control 119 a Net Yield Gain with Counter 15G 0 bu/a

20 AVICTA DUO CORN Seed Treatment Early season protection from nematodes and insects. Very Limited Availability on Corn

21 AVICTA DUO PERFORMANCE ON CORN IN 2008 Seed Treatments Root Fresh Weight Yield (bu/a) Apron XL Maxim XL Dynasty 100FS Apron XL Maxim XL Dynasty 100FS Cruiser 5FS Apron XL Maxim XL Dynasty 100FS AVICTA Duo Apron XL Maxim XL Dynasty 100FS COUNTER 15G K. Lawrence b 118 b 15.3 b 111 b 17.1 ab 140 a 17.9 a 149 a

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