Western Corn Rootworm Identification, Life Cycle, Damage and Management

Transcription

1 Western Corn Rootworm Identification, Life Cycle, Damage and Management By: Sammi Jo Smith

2 Personal Information Located in Columbus Junction, Iowa Member of 4-H and the FFA Raised show cattle and a miniature horse

3 Personal Information Family farm consists of approximately 2,000 acres of corn and soybeans

4 Personal Information

5 Personal Information

6 Personal Information

7 Education Western Illinois University ( ) Bachelor of Science Major Zoology Minor Chemistry Iowa State University ( ) Master of Agronomy

8 Personal Information

9 Author Profile Author Name: Professional Title: Sammi Jo Smith Lab Analyst Affiliation (Company / Department): Current professional work / research interests: Monsanto/Quality Control I started my career at Monsanto in 2007 as a laboratory analyst. My daily duties included running chemical tests on finished products of glyphosate and analyzing data. The results of the tests indicated to the production teams whether or not the process was running correctly and that the finished products were within regulation guidelines. 9

10 Western Corn Rootworm Identification, Life Cycle, Damage and Management 10

11 Module Contents Chapter 1: Introduction Chapter 2: Identification Chapter 3: Location and Adaptation Chapter 4: Life Cycle Chapter 5: Damage Chapter 6: Management Strategies Chapter 7: Summary 11

12 Chapter 1: Introduction Estimates show that over $1 billion is lost every year by American farmers due to the costs of insect management and yield loss inflicted by the WCR (America s Farmers, 2016). 12

13 Chapter 2: Identification Scientific classification Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: Coleoptera Family: Chrysomelidae (leaf beetle) Genus: Diabrotica Species: D. virgifera 13

14 Chapter 2: Identification w/crwlarv.html hp?idinformationmodule= &topicorder =4&maxto=11

15 Chapter 2: Identification Both sexes of the adult beetle are yellow to green in color, with a black stripe down the sides of the wings Male wing covers are often nearly entirely black while the female wings have more regular stripes The female beetle is also distinguishable from the male because of an enlarged abdomen Leaf beetles are among the most conspicuous beetles on plants (Clark et al., 2004)

16 Chapter 2: Identification ldcrops/insects/western_corn_rootworm/ extension.entm.purdue.edu

17 Chapter 3: Location and Adaptation Buffalo Gourd, Cucurbita foetidissima, Comanche County, Kansas.

18 Chapter 3: Location and Adaptation

19 Chapter 3: Location and Adaptation

20 Chapter 3: Location & Adaptation

21 Chapter 4: Life Cycle

22 Chapter 4: Life Cycle

23 Chapter 4: Life Cycle

24 Chapter 4: Life Cycle

25 Chapter 4: Life Cycle 1 st and 2 nd instars of development Larvae are extremely small and soft-bodied Movement is accomplished via interconnected air filled pores in the soil Movement limited by pore size, type, texture and bulk density of the soil Mortality rate is high because their soft-bodies are easily punctured or scraped off during movement within coarse soils Larvae feed on fine root hairs and burrow into newly formed root tips

26 Chapter 4: Life Cycle 3 rd instar of development Most plant damage occurs during this stage Larvae feed and tunnel into the primary root system of the corn plant, including brace roots and crown, which reduces rooting depth and density Larvae become stronger and less prone to injury Growth of a body shield, composed of chitin, occurs *Chitin: A fibrous substance consisting of polysaccharides and forming the major component in the exoskeleton of arthropods

27 Chapter 4: Life Cycle

28 Chapter 4: Life Cycle Emergence begins from late June through early August Male adult beetles emerge 5-7 days before the adult female beetles Two weeks after emergence, beetles will mate and begin to lay eggs into the soil Adult beetles feed on leaf tissue, silks, tassels and pollen bgimage?from=24

29 Chapter 4: Life Cycle

30 Chapter 4: Life Cycle

31 Chapter 4: Life Cycle

32 Chapter 5: Damage rop-management/corn-insect-disease/cornrootworm/ cropsipm/insects/corn-rootworms.php

33 Chapter 5: Damage

34 Chapter 5: Damage eldcrops/insects/western_corn_rootworm/

35 Chapter 5: Damage path/corn/rw/ stalklodge.html

36 Chapter 5: Damage cm/2006/7-17/

37 Chapter 5: Damage

38 Chapter 5: Damage

39 Chapter 5: Damage Rating corn root damage To assess the level and amount of root damage inflicted by the WCR larvae, corn roots are rated according to a scale called the Node-Injury Scale. In this scale, zero represents no damage to the roots and three represents severe damage.

40 Chapter 5: Damage

41 Chapter 5: Damage

42 Chapter 5: Damage

43 Chapter 5: Damage

44 Chapter 6: Management Strategies Utilizing an integrated pest management strategy is an effective way to determine which management strategies will lead to a desired outcome Uses economic injury levels and economic threshold levels to relate pest damage to the dollar value of lost yield and cost to control pest Desired outcome is to reduce levels of damage to a corn plant s rooting system so that the loss in yield becomes economically insignificant (Levine, et al., 2016) *Economic injury level: The smallest number of insects (amount of injury) that will cause yield losses equal to the insect management costs. *Economic threshold: The pest density at which management action should be taken to prevent an increasing pest population from reaching the economic injury level

45 Chapter 6: Management Strategies Three types of management strategies Cultural Crop scouting, employing deterrents, crop rotation and early planting date Chemical Insecticides, seed treatments and repellants Biological Biopesticides, genetic modification and microbial insecticides

46 Chapter 6: Management Strategies -scouting-competition-2015-open-enrollment

47 Chapter 6: Management Strategies Crop scouting This graph indicates the time of year to scout for the WCR adult beetle Scouting from mid-may through July will assist is WCR management

48 Chapter 6: Management Strategies

49 Chapter 6: Management Strategies

50 Chapter 6: Management Strategies

51 Chapter 6: Management Strategies

52 Chapter 6: Management Strategies

53 Chapter 6: Management Strategies

54 Chapter 6: Management Strategies

55 Chapter 6: Management Strategies

56 Chapter 7: Summary