Rice Water Weevil (RWW) Management Update. Luis Espino Rice Farming Systems Advisor UCCE

Transcription

1 Rice Water Weevil (RWW) Management Update Luis Espino Rice Farming Systems Advisor UCCE

2 Early Season Rice Invertebrate Pests Rice seed midge Tadpole shrimp Rice water weevil

3 Flooding Seeding 1 lsr 3 lsr 5 lsr

4 Seed Midge Flooding Seeding 1 lsr 3 lsr 5 lsr Larvae feed on seed embryo and emerging shoots leaves Drain field Seed soon after flooding

5 Tadpole Shrimp Flooding Seeding 1 lsr 3 lsr 5 lsr Feed on seed shoots, uproot seedlings, muddy water No problem after leaves reach water surface Drain field Seed soon after flooding Carbaryl, copper sulfate

6 Monitoring Scout fields during first and second week after flooding First week: 30 healthy seedlings/sq ft Second week: 25 healthy seedlings/sq ft

7 Rice Water Weevil Flooding Seeding 1 lsr 3 lsr 5 lsr Larvae feed on roots Tillering and yield reduced, maturity delayed

8 Management Weed control Clean levees Winter flooding Warrior, Mustang = kill only adults Dimilin = sterilizes adult females No effect on larvae! Timing of application critical: 1 3 lsr Apply borders and levees only (30 50 feet)

9 Monitoring Field history Field observations: feeding scars, adult weevils

10 2009 Treated Acres Insecticide Field size Area treated Average % Warrior 143,620 65, Mustang 50,580 25, Dimilin 1, All 195,954 91,833 47

11 % RWW Insecticide Applications 2009 < >90 % Area Treated

12 RWW Experiments Are RWW populations higher near the field s edge? What is the effect on yield?

13 Experimental Set up Treated 200 ft 100 ft 15 ft Untreated

14 Larval Sampling 4 4 Larvae/core

15 Range of Average RWW Populations Experiment Sampling time First (6 was) Second (8 was) Colusa Maxwell Princeton Colusa Maxwell

16 Colusa 09

17 Princeton 09

18 Are RWW populations higher near the field s edge? RWW populations higher in field borders in 4 out of 5 fields, 2 years Border populations ranged from 0.6 to 3.8 larvae/core

19 RWW Yield Studies Year Effect on Yield % (cages, 1 adult/plant) % % (4 5 larvae/plant) % (6 10 larvae/core) % (9.4 larvae/core) 2010 No significant yield reduction

20 Yield (lbs/a) Experiment Treated Untreated Colusa 09 5,262 4,998 Maxwell 09 8,809 8,800 Princeton 09 10,317 10,283 Colusa 10 8,717 8,520 Maxwell 10 8,734 8,890

21 Effect on yield Yield reduction possible Difficult to assess N overlap, other border problems SCOUT YOUR FIELD EVALUATE NEED FOR APPLICATION Pre flood treatments in known problem fields Post flood treatments: scout field Evaluate presence of other pests Not sure? Call me

22 Summary Border applications for RWW control recommended Scout your fields to determine if treatment is needed, evaluate effect on yield

23 Stored Rice Insects Luis Espino, UC Cooperative Extension Cass Mutters, UC Cooperative Extension Jim Thompson, UC Davis

24 Stored Rice Insects Insect infestations can cause: Reduction of grade Fumigation due to infested classification Spoilage Not much information from rice in CA What are the problems? What are possible solutions? Objectives: document species composition and population dynamics

25 Insect Survey Three dryers: warehouses and around facilities Three farm metal bins

26 Monitoring Pheromone traps Angoumois grain moth Indianmeal moth Lesser grain borer Probe traps

27 Pheromone Traps Dryer: Flat Bed Warehouse February August Insects/pheromone trap/day Farm Bins October April No AGM, LGB or IMM found in pheromone traps 0 2/19 3/19 4/19 5/19 6/19 7/19 AGM LGB IMM AGM

28 Probe traps Dryer: Flat Bed Warehouse February August Farm Bins October April Insects/probe Insects/probe AGM SFB HFB

29 Farm Bin October April 3.0 Bin Insects/probe/day 10/30 11/30 12/31 1/31 2/28 3/31 HFB SFB

30 Summary Dryers Angoumois grain moth most abundant spring and summer Farm Bins Mold feeding beetles most abundant Hairy fungus beetle Silken fungus beetle Angoumois grain moth and lesser grain borer not found AGM Grain moisture content Weather conditions SFB HFB

31 2011 Mail Survey of Management Practices What are the problems encountered? What management practices are being used? How can we improve management at farm and dryer level? Your participation is VERY IMPORTANT

32 Thank You!