Docstoc

Crop Profile for Watercress in Hawaii

Document Sample
Crop Profile for Watercress in Hawaii Powered By Docstoc
					    Crop Profile for Watercress in Hawaii
                  General Production Information
   Watercress is a staple leafy green vegetable crop in Hawaii.
   Commercial acreage has been steady for at least 10 years and was 35 acres in 2002
    (Hawaii Ag Statistics Service 2002).
   Total production in 2002 was 800,000 lbs. for an average per acre per year yield of
    22,857 lb. (Hawaii Ag Statistics Service 2002).
   Watercress is continuously cultivated year-round with an average of 6 to 8 crop cycles
    per year.
   Total value of the Hawaii watercress industry was $946,000 in 2001 and $944,000 in
    2002. Average farm price in 2002 was $1.18 per pound (Hawaii Agricultural Statistics
    Service 2002).
   Average production costs are approximately $20,000 per acre per year (costs include rent,
    labor, and farm chemicals) (Watercress of Hawaii Inc., personal communication).
   100% of harvested watercress is for fresh market use (Hawaii Agricultural Statistics
    Service 2002).
   Watercress is not exported because the demand is greater than the supply.
   Ninety-five percent of commercial watercress production is on the island of Oahu in the
    Aiea, Pearl City, and Waipahu areas. The remaining 5% is in Haiku and Kihei on Maui.
    Additionally, there is dryland watercress production on the island of Hawaii in the
    Mountain View area. The amount of dryland production is not reported by the Hawaii
    Agricultural Statistics Service (Watercress of Hawaii, Inc. personal communication).
   1% of production is grown hydroponically.
   Approximately 12 growers on Oahu, 2 on Maui, and 1 on Big Island.
   The largest farm size is 10 acres and the smallest farm is ¼ acre.

                                  Production Regions
                                   Cultural Practices
Watercress is grown continuously throughout the year in Hawaii. Watercress fields are located
in areas where there is abundant spring or artesian well water. Watercress cannot be grown
commercially using stream or river water because of the potential for animal or human
contamination.

Watercress beds or patches are prepared by firming the soil with rocks and gravel. Watercress
does not tolerate muddy field conditions. Beds are slightly graded (1% slope from the top to the
bottom of a bed) to allow for continuous water flow over the surface of the patch. The film of
water is very shallow (0.5 to 1.5 inches) which allows roots to attach to the gravel surface of the
bed. The desired pH of the water and the beds is neutral (7.0). Watercress planting is by
vegetative cuttings laid on top of the prepared beds in the direction of the water flow.

Because watercress is a leafy vegetable it is sunlight and day length sensitive. The higher the
percentage of sunshine the faster the crop grows. In growing areas with leeward sunlight
exposure watercress can be harvested 6 to 7 weeks after planting. After the initial planting the
subsequent crops are produced by ratoons of the “mother” plants. If growing conditions are
favorable then watercress can be grown as a ratoon crop indefinitely.

Nutrient requirements are provided by the mineral content of the irrigation water. There is some
supplemental fertilization of watercress by individual growers but no standards have been
established.

Watercress is harvested by hand using a hand sickle when the plant has grown 12 to 15 inches
above the water surface. After harvest and packaging watercress is quick chilled using vacuum
cooling or an ice water bath. There is a high percentage of hand labor required to produce
watercress. Those activities requiring hand labor are planting, weeding, harvesting, packaging,
and insect pest control (McHugh et al. 1987).



                                   Invertebrate Pests
                                           Aphids
                               Buckthorn Aphid (Aphis nasturtii)
                              Green Peach Aphid (Myzus persicae)

Aphids are an intermittent pest on watercress. Outbreaks usually occur after several successive
days of strong tradewinds (greater than 10 mph). Heavy aphid infestations can cause an
unmarketable appearance of watercress because the presence of a single live (or dead) aphid on
the finished product can lead to customer rejection (Nakahara et al. 1986).

Control
Chemical Control:
   Diazinon (Clean Crop Diazinon 500 AG, Diazinon 50W) – PHI = 5 days, REI = 24 hrs.
     Applied as a directed spray to plant canopy, at a rate of 0.5 lb a.i./acre. Registration was
     cancelled by EPA in May 2002. Watercress industry was granted a 4-year withdrawal
     period by EPA to expire in May 2006 (Watercress of Hawaii, Inc. personal
     communication).

      Malathion (Drexel Malathion 5 EC, Griffin Atrapa 5E, Malathion 5, Micro Flo
       Malathion 5EC, Prozap Malathion 57EC) – PHI = 7 days, REI = 12 hrs. Applied as a
       directed spray to plant canopy, at a rate of 0.5 lb a.i./acre (HPIRS 2004).

      Imidacloprid (Provado 1.6) – PHI = 7 days, REI = 12 hrs. Applied as a directed spray to
       crop canopy, at a rate of 0.047 lb a.i./acre.

Alternative Chemical Control:
    Dinotefuran is a possible alternative insecticide but needs testing.

Non-chemical Control:
   Predators (ladybugs, Syrphid flies) and parasites are present in watercress fields but do
      not give adequate control (Nakahara et al. 1986).


                                        Cyclamen mite
                                    Stenotarsonemus pallidus

Cyclamen mite has been a pest of watercress since the 1950’s. Cyclamen mite feeding begins in
the apical shoot of the plant. Damage symptoms are shoot and leaf stunting, bronzing of leaf
tissue, and deformation of the entire plant with heavy mite infestations. Cyclamen mite is
widespread and found in all watercress growing areas (McHugh et al. 1987).

Control

Chemical Control:
   Diazinon (Clean Crop Diazinon 500 AG, Diazinon 50W) – PHI = 5 days, REI = 24 hrs.
     Applied as a directed spray to plant canopy, at a rate of 0.5 lb a.i./acre. Registration was
     cancelled by EPA in May 2002. Watercress industry was granted a 4-year withdrawal
     period by EPA to expire in May 2006 (Watercress of Hawaii, Inc. personal
     communication).

Alternative Chemical Control:
    None

Non-chemical Control:
Intermittent overhead irrigation is very effective in controlling cyclamen mite (McHugh et al
1987, Nakahara et al. 1986).

                                      Diamondback moth
                                       Plutella xylostella

Diamondback moth is the most serious insect pest of watercress in Hawaii. The caterpillar stage
of the insect does damage to the plant by feeding on the leaves and the young growing shoots.
The life cycle of the moth is very rapid. Eggs are laid on the under surface of the leaves and in
the growing points. Egg to adult maturation can occur in as little as 12 days but averages 21
days in most watercress growing areas. The diamondback moth is world renown for its ability to
quickly develop resistance to any insecticide used to control it. The diamondback moth feeds
exclusively on cruciferous host plants (cultivated and weed hosts) (Shelton et al. 1993, Talekar
1992, Tabashnik et al. 1990, Tabashnik et al. 1987).

Control

Chemical Control (HPIRS 2004):
   Spinosad (Success) – PHI = 1 day, REI = 4 hrs. Applied as a directed spray to plant
     canopy at a rate of 0.02 – 0.05 lb a.i./acre.

      Bacillus thuringiensis (subspecies Kurstaki, various products) – PHI = 0 days, REI = 4
       hrs. Applied as a directed spray to plant canopy at a rate of 0.2 – 0.8 lb a.i./acre.

Alternative Chemical Control:
    None

Non-chemical Control:
   Intermittent overhead irrigation is effective in controlling diamondback moth in
      combination with the parasitoid wasp Cotesia plutella which is established in all
      watercress growing areas (McHugh and Foster 1994, Nakahara et al. 1986, Tabashnik
      and Mau 1986).

                                   Imported cabbageworm
                                        Pieris rapae

Imported cabbageworm is an occasional pest of watercress. Damage to the crop is by the
caterpillar stage of the butterfly. Adults are white butterflies commonly seen searching for
nectar along roadside weed stands. Outbreaks often appear from the months of February through
June. Leaves are damaged by larval feeding which render the crop unmarketable. Imported
cabbageworm is easy to control with registered insecticides (Knowledge Master 2004).

Control
Chemical Control:
   Bacillus thuringiensis (subspecies Kurstaki, various products) – PHI = 0 days, REI = 4
     hrs. Applied as a directed spray to plant canopy at a rate of 0.2 – 0.8 lb a.i./acre (HPIRS
     2004).

      Diazinon (Clean Crop Diazinon 500 AG, Diazinon 50W) – PHI = 5 days, REI = 24 hrs.
       Applied as a directed spray to plant canopy, at a rate of 0.5 lb a.i./acre. Registration was
       cancelled by EPA in May 2002. Watercress industry was granted a 4-year withdrawal
       period by EPA to expire in May 2006 (Watercress of Hawaii, Inc. personal
       communication).

      Malathion (Drexel Malathion 5 EC, Griffin Atrapa 5E, Malathion 5, Micro Flo
       Malathion 5EC, Prozap Malathion 57EC) – PHI = 7 days, REI = 12 hrs. Applied as a
       directed spray to plant canopy, at a rate of 0.5 lb a.i./acre (HPIRS 2004).

      Spinosad (Success) – PHI = 1 day, REI = 4 hrs. Applied as a directed spray to plant
       canopy at a rate of 0.02 – 0.05 lb a.i./acre (HPIRS 2004).


Alternative Chemical Control:
    None.

Non-chemical Control:
   Parasites are present but do not give acceptable control of imported cabbageworm.

                                       Sharpshooters
                      Draeculecephala californica, D. inscripta, D. minerva

Sharpshooters are minor pests of watercress. These small insects are commonly found on grass
but can build to high numbers on watercress. Nymph and adult stages cause damage to
watercress called “hopper burn”. “Hopper burn” is a condition that results in localized yellowing
of the watercress leaves and leaflets and can render the crop unmarketable. The grass
sharpshooter is easy to control with timely application of approved insecticides (Nakahara et al.
1986).

Control

Chemical Control:
   Diazinon (Clean Crop Diazinon 500 AG, Diazinon 50W) – PHI = 5 days, REI = 24 hrs.
     Applied as a directed spray to plant canopy, at a rate of 0.5 lb a.i./acre. Registration was
     cancelled by EPA in May 2002. Watercress industry was granted a 4-year withdrawal
     period by EPA to expire in May 2006 (Watercress of Hawaii, Inc. personal
     communication).
      Malathion (Drexel Malathion 5 EC, Griffin Atrapa 5E, Malathion 5, Micro Flo
       Malathion 5EC, Prozap Malathion 57EC) – PHI = 7 days, REI = 12 hrs. Applied as a
       directed spray to plant canopy, at a rate of 0.5 lb a.i./acre (HPIRS 2004).

      Imidacloprid (Provado 1.6) – PHI = 7 days, REI = 12 hrs. Applied as a directed spray to
       crop canopy, at a rate of 0.047 lb a.i./acre.

Alternative Chemical Control:
    Dinotefuran is a possible alternative insecticide but needs testing.

Non-chemical Control:
   None.

                                        Snails and Slugs
                                         Various species

Snails and slugs can become a problem on watercress when they move high up on the plant
stalks at the time of harvest. The presence of slugs or snails on watercress can lead to market
rejection of the finished product. Slug and snail pressure increases during rainy periods or from
excessive moisture supplied by intermittent overhead irrigation systems used by watercress
growers to control diamondback moth (Watercress of Hawaii, Inc. personal communication).

Control
Chemical Control:
   None.

Alternative Chemical Control:
    None.

Non-chemical Control:
   Adjust intermittent overhead irrigation during periods of high rainfall or when slugs or
      snails are noticed high up on the plants.
   Remove by hand at time of harvest (Watercress of Hawaii, Inc. personal communication).

                                          Stinkbugs
                                 A Lygaeid Bug (Nysius spp.)
                           Southern Green Stinkbug (Nezara viridula)

Stinkbugs are occasional pests of watercress and occur mostly during the months of May and
June. Feeding of stinkbugs causes wilting of shoots, stems, and/or leaves above the feeding
point. Nymphal and adult stages of stinkbugs can damage watercress but are easily controlled
with timely applications of approved insecticides (Knowledge Master 2004).

Control
Chemical Control:
   Diazinon (Clean Crop Diazinon 500 AG, Diazinon 50W) – PHI = 5 days, REI = 24 hrs.
     Applied as a directed spray to plant canopy, at a rate of 0.5 lb a.i./acre. Registration was
     cancelled by EPA in May 2002. Watercress industry was granted a 4-year withdrawal
     period by EPA to expire in May 2006 (Watercress of Hawaii, Inc. personal
     communication).

      Imidacloprid (Provado 1.6) – PHI = 7 days, REI = 12 hrs. Applied as a directed spray to
       crop canopy, at a rate of 0.047 lb a.i./acre (HPIRS 2004).

      Malathion (Drexel Malathion 5 EC, Griffin Atrapa 5E, Malathion 5, Micro Flo
       Malathion 5EC, Prozap Malathion 57EC) – PHI = 7 days, REI = 12 hrs. Applied as a
       directed spray to plant canopy, at a rate of 0.5 lb a.i./acre (HPIRS 2004).

Alternative Chemical Control:
    Dinotefuran is a possible alternative insecticide but needs testing.

Non-chemical Control:
   There are three parasites of Southern green stinkbug, Trichopoda pennipes, T. pilipes,
      and Trissolcus basalis which give good control most of the year.


                                    Watercress leafhopper
                                   Macrosteles sp. nr. severini

The watercress leafhopper is one of the most serious insect pests of watercress because it is the
vector of the phytoplasma disease Aster Yellows. The leafhopper is a recent introduction to
Hawaii and first discovered on watercress in 2001. Aster Yellows disease causes severe
chlorosis, stunting, and a “witch's broom” effect on new watercress shoots. Aster yellows
infected watercress is unmarketable (Hawaii Department of Agriculture 2003).

Control

Chemical Control:
   Diazinon (Clean Crop Diazinon 500 AG, Diazinon 50W) – PHI = 5 days, REI = 24 hrs.
     Applied as a directed spray to plant canopy, at a rate of 0.5 lb a.i./acre. Registration was
     cancelled by EPA in May 2002. Watercress industry was granted a 4-year withdrawal
     period by EPA to expire in May 2006 (Watercress of Hawaii, Inc. personal
     communication).
   Imidacloprid (Provado 1.6) – PHI = 7 days, REI = 12 hrs. Applied as a directed spray to
     crop canopy, at a rate of 0.047 lb a.i./acre (HPIRS 2004).
      Malathion (Drexel Malathion 5 EC, Griffin Atrapa 5E, Malathion 5, Micro Flo
       Malathion 5EC, Prozap Malathion 57EC) – PHI = 7 days, REI = 12 hrs. Applied as a
       directed spray to plant canopy, at a rate of 0.5 lb a.i./acre (HPIRS 2004).

Alternative Chemical Control:
    Dinotefuran is a possible alternative insecticide but needs testing.

Non-chemical Control:
   None.



                                          Diseases
                                         Aster Yellows

Aster Yellows (AY) is the most serious disease of watercress in Hawaii. AY was first detected
in a watercress field in Pearl City, Oahu in 2001. The disease is caused by a phytoplasma that
can infect numerous plant hosts (HDOA 2003). AY is vectored in Hawaii by the watercress
leafhopper which is known to feed on a variety of host plants. Symptoms of AY on watercress
are severe chlorosis and stunting, witch's broom effect on new shoots, and, in some cases, death
of the plant. Since its introduction, the AY phytoplasma has been found only in watercress or
weed plants adjacent to watercress fields (Smith et al. 2002). Adoption of recommended
watercress leafhopper control management practices is critical to control of this disease.

Control

Chemical Control:
   Elimination. Rogue infected plants but first spray an approved insecticide before
     watercress leafhoppers can move to uninfected plants. In addition to symptomatic plant
     removal all asymptomatic watercress within a 3 ft. radius of the infected plant must be
     removed.
   Border leafhopper control. Regular sprays of an approved insecticide for all vegetation
     within 50 ft. from edge of watercress field.

Alternative Chemical Control:
    None.

Non-chemical Control:
   Avoidance. Use of disease free watercress planting material once diseased plants have
      been removed from the field. Careful monitoring of replant areas to identify and remove
      symptomatic plants.
   Transgenic resistance. Research is needed in this area.
                                           Black Rot
                                     Xanthomonas campestris

Black rot can be a serious disease during prolonged rainy periods. The disease begins as a
yellow spot at the edge of the watercress leaflets. The disease is spread by splashing water
droplets (Knowledge Master 2004). Under heavy rainy conditions, especially during “kona
weather”, black rot can spread to the apical growing shoot causing plant stunting and
deformation. The use of intermittent overhead irrigation can also spread the disease if relative
humidity is high (> 80%) and wind is light (< 10 mph).

Control

Chemical Control:
   Copper hydroxide (Champ, Griffin Kocide, Nu-Cop) – PHI = 2 days, REI = 48 hrs.
     Applied as a directed spray to plant canopy at a rate of 0.75 – 1.5 lb a.i./acre (HPIRS
     2004).

Alternate Chemical Control:
    None.

Non-chemical Control:
   Stop intermittent overhead irrigation (used for diamondback moth control) until trade
      winds return.
   Minimize free moisture on crop leaves. Sprinkler system used to control diamondback
      moth turned off during prolonged rainy periods (> 2 days) or during times of high relative
      humidity (> 80%) during the daylight hours.


                                     Cercospora Leaf Spot
                                      Cercospora nasturtii

Cercospora leaf spot is an occasional pest caused by high humidity (>80%). Mostly older leaves
are affected but the disease can sometimes be found high up on the plant if the conditions which
favor the disease (heat and high humidity) are prolonged (Knowledge Master 2004). Growers
rarely spray for this disease.


Control

Chemical Control:
   Copper hydroxide (Champ, Griffin Kocide, Nu-Cop) – PHI = 2 days, REI = 48 hrs.
     Applied as a directed spray to plant canopy at a rate of 0.75 – 1.5 lb a.i./acre (HPIRS
     2004).
      Azoxystrobin (Quadris) – PHI = 7 days, REI = 4 hrs. Applied as a directed spray to
       plant canopy at a rate of 0.10 – 0.25 lb a.i./acre (HPIRS 2004).

Alternate Chemical Control:
    None.

Non-chemical Control:
   Remove infected leaves by hand when harvesting.



                                          Weeds
Weed control is generally not a major concern in watercress fields. Intermittent overhead
irrigation used for diamondback moth control creates conditions which do not favor the
proliferation of weed species. Additionally, flooded fields that are needed for watercress
production limit the establishment of weeds in actively grown fields. Weed intrusion mostly
occurs near the edges of watercress fields. The main weed pests are: California grass
(Brachiaria mutica) (Holm et al. 1977), honohono grass (Commelina diffusa) (Holm et al. 1977),
and water hyssop (Bacopa sp.).

Control

Chemical Control:
   Glyphosate (Various products) – PHI = N/A (not for crop application), REI = 4 hrs.
     Applied as a border control spot spray. Applied at various rates. Not effective on
     honohono grass. Partially effective on water hyssop.

Alternate Chemical Control:
    None.

Non-chemical Control:
   Hand weeding as needed.




                                        Contacts
Profile drafted by:

John J. McHugh, Jr.
Crop Care Hawaii, LLC
2923A Kaamalio Dr.
Honolulu, HI 96822
Lynne N. Constantinides
Crop Care Hawaii, LLC
2923A Kaamalio Dr.
Honolulu, HI 96822

Cathy Tarutani-Weissman
Plant and Environmental Protection Sciences
College of Tropical Agriculture and Human Resources
University of Hawaii-Manoa
Honolulu, Hawaii, 96822
(808) 956-2004

Reviewed and Approved by:

Michael Kawate
Extension Pesticide Coordinator
Plant and Environmental Protection Sciences
College of Tropical Agriculture and Human Resources
University of Hawaii-Manoa
Honolulu, Hawaii 96822
(808) 956-6008


                                     References
   1. College of Tropical Agricultural and Human Resources, University of Hawaii at Manoa.
      2001. http://www.ctahr.hawaii.edu/ctahr2001/CTAHRInAction/Dec_01/watercress.html
   2. Hawaii Agricultural Statistics Service. 2002. http://www.nass.usda.gov/hi/stats/stat-
      51.htm
   3. Hawaii Department of Agriculture, New Pest Advisory No. 02-01. 2003.
      http://www.hawaiiag.org/hdoa/npa/npa02-01-wcleafhopper.pdf
   4. Hawaii Pesticides Information Retrieval System. 2004.
      http://state.ceris.purdue.edu/htbin/sitesetp.com
   5. Holm, L. G., D. L. Plucknett, J. V. Pancho, J. P. Herberger. 1977. The World’s Worst
      Weeds. University of Hawaii Press.
   6. Knowledge Master. 2004. University of Hawaii, College of Tropical Agriculture and
      Human Resources, University of Hawaii-Manoa. Computer Resource Database.
      http://www.extento.hawaii.edu/kbase/crop/Type/cer_prim.htm
   7. Knowledge Master. 2004. University of Hawaii, College of Tropical Agriculture and
      Human Resources, University of Hawaii-Manoa. Computer Resource Database.
      http://www.extento.hawaii.edu/kbase/crop/Type/pieris.htm
8. Knowledge Master. 2004. University of Hawaii, College of Tropical Agriculture and
    Human Resources, University of Hawaii-Manoa. Computer Resource Database.
    http://www.extento.hawaii.edu/kbase/crop/Type/xanthomo.htm
9. McHugh, J. J., Jr., and R. E. Foster. 1995. Reduction of diamondback moth (Lepidoptera:
    Plutellidae) infestation in head cabbage by overhead irrigation. J. Econ. Entomol. 88:
    162 – 168.
10. McHugh, J. J., Jr., S. K. Fukuda and K. Y. Takeda. 1987. Hawaii Watercress Production.
    HITAHR. Res. Ext. Series 088.
11. Nakahara, L. M., J. J. McHugh, Jr., C. K. Otsuka, G. Y. Funasaki and P. Y. Lai. 1986.
    Integrated control of diamondback moth and other insect pests using an overhead
    sprinkler system, an insecticide, and biological control agents on a watercress farm in
    Hawaii. In N. S. Talekar and T. D. Griggs (eds.), Diamondback Moth Management:
    Proceedings of the First International Workshop, pp. 403 – 413. Asian Vegetable
    Research and Development Center, Shanhua, Taiwan.
12. Shelton, A. M., J. A. Wyman, N. L. Cushing, K. Apfelbeck, T. J. Dennehy, S. E. R.
    Mahr, and S. D. Eigenbrode. 1993. Insecticide resistance of diamondback moth
    (Lepidoptera: Plutellidae) in North America. J. Econ. Entomol. 86: 11 – 19.
13. Smith, H. A., J. J. McHugh, Jr. and B. R. Kumashiro. 2002. Monitoring a Newly
    Introduced Watercress Leafhopper in Central Oahu. Hawaii Agriculture Experiment
    Station, Vegetable Report 4.
14. Tabashnik, B. E., N. L. Cushing, N. Finson and M. W. Johnson. 1990. Field development
    of resistance to Bacillus thuringiensis in diamondback moth (Lepidoptera: Plutellidae). J.
    Econ. Entomol. 83: 1671 – 1676.
15. Tabashnik, B. E., N. L. Cushing and M. W. Johnson. 1987. Diamondback moth
    (Lepidoptera: Plutellidae) resistance to insecticides in Hawaii: intra-island variation and
    cross-resistance. J. Econ. Entomol. 80: 1091 – 1099.
16. Tabashnik, B. E. and R. F. L. Mau. 1986. Suppression of diamondback moth
    (Lepidoptera: Plutellidae) oviposition by overhead irrigation. J. Econ. Entomol. 79:
    1447 – 1457.
17. Talekar, N. S. (ed.) 1992. Diamondback Moth and other Crucifer Pests: Proceedings of
    the Second International Workshop. Asian Vegetable Research and Development Center,
    Tainan, Taiwan.
18. Watercress of Hawaii, Inc. (watercress growers association). 2004. Personal
    communication.

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:31
posted:4/29/2010
language:English
pages:12