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Green-Seeds.com
Fruits
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Papaya
By Products
Further utilization of processed papaya products would be very important
to the industry because culls average 40 percent of total production.
On Kauai, there is no processing facility at the major packing plant
to handle the culls. One small processor utilizes the culls on a limited
and irregular basis.
Aseptic packaging is being used very successfully in Hawaii.
Several products have been developed experimentally: solar dried, osmo-sol,
osmovac-dried, freeze-dried slices, and vacuum-puff freeze-dried nectar
base. Sun dried papaya from culls tastes like dried apricots and stores
well.
Where there are no facilities for processing purees, the bulk of the
culled fruits are used for animal feed. Culled fruits could be fed fresh
or ensiled for fresh storage and fed to pigs or cattle. The high cost
of drying and shipping would limit any livestock industry using papaya
by-products to the main areas of production only.
Capital
--------------------------------------------------------------------------------
 New farmers with personal
and/or family assets that can be used to help finance their enterprises
will find it easier to get financing from available lenders.
The Farmers Home Administration
has a new entry loan program. The FmHA should be contacted for more information.
The State's Agricultural
Loan Program, governed by Chapter 155, HRS, is intended to assist farmers
who are unable to secure loans from private lenders or the Farmers Home
Administration. The program is also intended to maximize use of limited
state funds and resources and to meet the needs of qualified farmers of
all commodities.
Act 222, SLH 1979, adjusted
the interest rates of DOA farm loans to be comparable with rates of applicable
Farm Credit Banks, except for emergency loans and loans to new farmers and
cooperatives. The legislative intent is that viable farmers should secure
financing from conventional sources.
The DOA Farm Loan program
has a $75,000 ceiling on new farmer loans. Additional financing up to a
total of $200,000 can be obtained later from DOA if the farmer shows that
he is operating a viable farm, and he is a good risk for additional financing.
Where the cost of the
project exceeds the DOA loan ceiling, in many instances, the DOA has been
able to bring in other lenders to participate in financing.
Extending information
on loan programs and assisting farmers to secure financing from other sources
as well as the state has been an on-going function of the DOA Agricultural
Loan Division. CTAHR, primarily through its extension agents, has assisted
by referring loan inquiries to the DOA.
There is a general need
for farmers to be educated in financial management and the use of credit.
Availability of education and training programs in farm and financial management
on a continuing basis is needed.
There are times when
farmers cannot obtain credit when needed.
The communication between
lenders and borrowers (farmers) is inadequate.
Few papaya loans are
made by the State. Production Credit Association lends extensively to papaya
producers.
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Costs
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A HITAHR Series Report
entitled "The Economic Viability of Papaya Farms in the Puna District"
was released in February, 1984. This comprehensive study includes detailed
budget analyses for 5-, 10-, and 50-acre farm models. Economic viability
is indicated by cash flow and expenditure analyses and profitability is
determined by internal rate of return, benefit-cost ratios, and sensitivity
analyses. Average annual per acre net return to risk for the 3 year life
of the planting amounted to $604 for the 5-acre farm, $2,252 for the 10-acre
farm, and $2,443 for the 50-acre farm. Internal economic rate of return
amounted to 50% of the 5-acre farm and 69% for the 10-acre and 50-acre farms..
The benefit-cost ratios were 1.6, 1.8, and 1.9, respectively, for the 5-,
10-, and 50-acre models.
Cost of production studies
should be expanded to include all important production areas in the State
classified by farm size and whether irrigated or non-irrigated.
Lending institutions
need cost of production information to assess the profitability and viability
of the industry so that loan applications from farmers can be properly considered.
Farms need cost of production
data to help them make rational decisions concerning capital improvements.
The 1984 Puna study
based on 1980 input-output prices is already out of date. The Department
is now in the process of developing a data bank that can be quickly updated.
Periodic data will be released. Farmers can also put in their own data and
calculate cost to compare with the industry mean.
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Cultivars
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The farmers in Puna
grow mostly the 'Kapoho Solo' or selections of the Kapoho. Some 'Sunrise'
is also grown, mostly for the Japanese market. The 'Sunrise' in Puna tends
to produce fruits larger than desired.
Most of the 'Sunrise'
production is from Kauai. Both the 'Sunrise' and 'Kapoho' are exported.
The farmers on Oahu
grow the Waimanalo (X-77) or their own selections from this cultivar for
the local market.
New varieties, if not
properly tested for postharvest qualities, may cause marketing and handling
problems.
The Waimanalo cultivar
seems to have some resistance to Phytophthora root rot. Efforts to transfer
this disease resistance to the 'Kapoho' have been initiated. 'Sunrise' appears
to be susceptible to Phytophthora. On Kauai, Phytophthora losses amounted
to about 60 percent or more in 1982 ($2,000,000). Additional multidisciplinary
research is required because Phytophthora is a statewide problem.
An introduced dioecious
papaya line with tolerance to the papaya ringspot virus has been crossed
with Hawaiian commercial cultivars. The F2 (second generation) selections
show moderate tolerance, but generally inferior fruit qualities. Also, some
wild Carica species are apparently resistant to the virus, and these have
been successfully crossed with commercial papayas to produce virus-resistant
breeding materials.
A relatively successful
technique for the tissue culture propagation of papayas has been developed
by the Hawaii Sugar Planters' Association. Some sex changes were noted in
propagated plants.
Papayas are currently
shipped at 50oF. Lower temperatures (40oF) could control insects, diseases,
and ripening better, but will also injure immature fruits of current varieties.
Ripe fruits are less sensitive to lower temperatures. Interspecific hybridization
of papaya and a cold tolerant wild species, recently achieved, may lead
to the eventual development of chill-tolerant papaya cultivars.
Cultivar differences
such as size, disease susceptibility, ripening, flesh color, and responses
to different environmental factors have been observed. For example, 'Sunrise'
from Kauai tends to be slightly larger and ripens faster than the 'Kapoho
Solo' from the Big Island.
Standard yellow fleshed
'Solo' cultivars are highly inbred, assuring uniform progeny from seed.
The inbred nature of the yellow fleshed 'Solo' cultivars may contribute
to their notoriously narrow adaptation. Development of F1 hybrid hermaphrodite
cultivars would assure continued crop uniformity, while permitting the broader
environmental adaptation found in some heterozygous (hybrid) genotypes.
On the other hand, the red fleshed 'Sunrise Solo' cultivar, which makes
up more than 95 percent of world production of 'Solo' papayas, is highly
adaptable. This accounts for its popularity with growers in many countries
where yellow 'Solo' cultivars perform poorly.
'UH Rainbow' papaya--a
high-quality hybrid with genetically engineered disease resistance. CTAHR
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Cultural Practice
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Tissue Samples
The critical petiole concentrations of nitrogen (N) and phosphorus (P)
for optimum growth of prebearing trees of 'Kapoho Solo' at Puna were found
to be:
N = 1.20% - 1.35%
P = 0.16% - 0.19%
Also, from experiments conducted in Puna, the critical petiole concentrations
of N, P, and potassium (K) in bearing trees of 'Kapoho Solo' for optimum
yield were found to be:
N = 1.25% - 1.40%
P = 0.17% - 0.19%
K = 2.5% - 3.0%
From experiments conducted at Princess Orchard on Maui, the critical
petiole concentration of N for optimum yield of the 'Solo' papaya trees
in irrigated production seems to be:
N = 0.82% - 0.90% for Spring and Fall.
Micronutrient levels are not known for certain but they seem to be adequate
except for boron, which may be limiting at times.
For older trees, critical N at Moloaa for 'Sunrise Solo' is 1.24%. Critical
P and K levels are not known.
The critical concentration of calcium (Ca) and magnesium (Mg) for vegetative
plants determined in the greenhouse in sand was found to be:
% Ca % Mg
__________________________________________________
Immature petiole* 0.50 - 0.64 --
Recently-matured petiole 0.73 - 0.93 0.22
__________________________________________________
(*The immature petiole is about the mid-point number of petioles on the
plant, starting from the reference petiole (2.5 cm) counting basipetally
to the recently matured petiole; e.g., if the first open flower on the
plant is No. 16, then it would be the No. 8th petiole.)
Irrigation
Drought can be a problem
in almost all growing areas. Yields decrease if trees are subject to water
stress, and fruit set is also affected, especially during the hot months.
Irrigation for papaya
is essential if the field has an annual rainfall of less than 50 inches
(e.g., dry areas on Maui and Kauai). When rainfall ranges from 60 to 100
inches, irrigation provides supplementary moisture.
The irrigation experiments
at Princess Orchard showed that about 10.8 gallons/tree/day should be applied
for maximum yield. When water cost and papaya return are considered, the
optimal irrigation practice will change based on the net gain in the papaya
fields. Soft fruits resulting from certain climatic conditions (e.g., dry
period followed by heavy rainfall) is a problem which needs to be researched.
Transplanting can reduce
the time it takes to get an orchard established, but transplants need adequate
moisture.
Research to determine
the effects of supplementary irrigation in Puna was initiated in 1977 and
is now terminated. The results did not conclusively show significant increase
in yield and growth except during drought periods when supplementary irrigation
did have significant benefits. The high cost installation factor must be
considered when planning for an irrigation system.
Seedlings
Three seedlings are
allowed to grow from each planting hole. When flower buds appear, sex is
determined and the female plants are removed. Usually, one hermaphrodite
plant is allowed to grow from each site.
A rapid and simple method
for determining the sex of young plants would be a valuable crop management
tool. There is a possibility that such a method could be developed through
the use of monoclonal antibody technology. This technology is new and involves
detecting and isolating hybridomal cell clones which produce specific antibodies.
If substance in leaves could be linked to specific sex types, specific monoclonal
cell lines can be isolated. The appropriate antibody could then be linked
with a dye which will enable early detection.
Alternatively, it may
be possible to create a genetic system of balanced lethals by mutation breeding,
in which females, being homozygous for a sex-linked lethal gene, would die
at an early stage of development. The hermaphrodites, being heterozygous,
would be conserved. Such populations would be self-roguing.
Cover Crops
More cover crops which
present minimal competition are needed in papaya plantings to control erosion.
Sunhemp is now being used on some Kauai farms.
Harvesting
Growers are harvesting
more frequently (at approximately 5-day intervals) to adjust to the new
USDA/APHIS fruit maturity requirements. This cuts down on the amount of
overripe fruits in the field, but it also increases harvesting costs.
Growers without mechanical
picking platforms have difficulty in determining the correct stage of fruit
maturity when harvesting from ground level.
Fruits not meeting the
new USDA/APHIS requirements for export to the U.S. mainland are now being
sent to the Honolulu market, leading to depressed prices and economic hardship
for the smaller farms which traditionally supply the local markets.
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Current Status
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The papaya industry
dropped from its number 4 rank among principal crop value in Hawaii in 1983
($11,591,000) to number 5 in 1984 ($9,196,000). Even with this 21% decrease,
it remains a major commodity with good potential.
Farms
There were 306 farms in the State in 1984, an increase of 35% from 1983.
Two-hundred and nineteen (71%) of the farms were on the island of Hawaii,
42 (14%) on Kauai, 40 (13%) on Oahu, and 5 (2%) on Maui/Molokai.
Acreage
There were 2,590 acres of papayas harvested in the State in 1984, an
increase of 22% from 1983. There were 2,165 acres (84%) on the island
of Hawaii, 320 acres (12%) on Kauai, 85 acres (3%) on Oahu, and 20 acres
(1%) on Maui/Molokai.
Production
In 1984, there was a
record of 80,500,000 lb. of papayas produced, an increase of 31% from 1983.
83% was utilized as fresh fruit, while 17% was processed. The price of fresh
fruits fell to 13.1 cents/lb. compared to 23.6 cents/lb. in 1983.
Begining September 1,
1984, Hawaii's papaya industry completed the conversion from ethylene dibromide
fumigation treatment for fruit fly control to the new double dip hot water
treatment method using less than one-quarter ripe fruits.
Ref.: "Statistics
of Hawaiian Agriculture 1984", Department of Agriculture.
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Diseases
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The breeding and selection
for disease-resistant cultivars (papaya ringspot virus, Phytophthora blight,
and Phytophthora root rot) is an ongoing program (see section on "Cultivars").
Epidemiological studies on Kauai and Hawaii suggest that establishment and
spread of Phytophthora blight require about 1 inch of weekly rainfall on
Kauai and about 2 inches of weekly rainfall on Hawaii. The DOA has conducted
roguing programs on Oahu and Hawaii for many years and has, thus far, prevented
the spread of the disease into the Puna area of Hawaii. Ongoing grower education
and recognition of the disease and how it can be spread is needed. Recent
discovery of papaya ringspot on Kauai will require the cooperation of DOA,
CES, and industry to control this new outbreak.
Phytophthora Canker and Fruit Rot
Phytophthora canker and fruit rot are continuing problems. Dithane M-45
is an effective protectant against these diseases as long as incidences
are low and rainfall is not continuous. The removal of inoculum sources
from the field when disease incidence is low is crucial to the control.
During severe epidemics, high incidence of advanced Phytophthora infections
(more than 24 hours old, but less than 48 hours) escape visual examination
at packing plants. These advanced infections are not adequately controlled
by the standard hot water treatment.
Fruit Rots
There are several important
fruit rots on papaya other than Phytophthora fruit rot. Anthracnose and
chocolate spots, caused by Colletotrichum gloeosporioides, and stem-end
rot caused by Rhizopus and Phoma are the most common, and research efforts
are focused on these in terms of fungicide applications and epidemiology.
Whereas anthracnose
can be controlled by an adequate field spray program, the same field sprays
decrease stem-end rots but do not satisfactorily control them. The best
control is by hot water treatment.
Thiabendazole (TBZ)
in postharvest treatment for papayas is now approved for use in the U.S.
Fungicide screening
is an ongoing program. Several new fungicides are currently being field-tested.
Currently registered fungicides have to be sprayed on a regular basis every
2-4 weeks depending on rainfall. An evaluation of spreader/stickers showed
that there is no one "best" adjuvant. Spreaders can be used for
conditions with less than 1 inch of rainfall per week, but spreader/stickers
should be used for wetter conditions.
New packing materials
are being evaluated for extended postharvest life of the fruits.
Tree nutrition studies
in the past were primarily evaluated on marketable yield. The effect of
nutrition (especially high nitrogen, form of nitrogen, and low calcium)
on disease susceptibility, if any, is not known, but may be significant.
New mist blower has
been designed by CTAHR, and the prototype has been tested successfully on
Kauai. The blueprints are available, and the machine is available for demonstration.
Powdery Mildew
Powdery mildew is present in orchards on Oahu and Kauai. Control is
by fungicide spray program.
Replant
The causative agents
for the yield-decline problem have been identified. They are basically the
same ones that are involved in the establishment of replant orchards.
Replant-yield decline
continues to be a problem on Hawaii and Kauai. Where soil conditions permit,
methyl bromide or Vapam can be used for soil fumigation. Ridomil and Truban
are effective in greenhouse tests for the control of Phytophthora and Pythium
root rots. Field tests at 3 locations showed that Ridomil did not alleviate
the problem, indicating that fungal root rots are not the only causal factors.
Soil analyses from several
areas in Puna revealed that high acidities (pH 4.2 - 5.2) were characteristic
of problem fields. Another characteristic of these problem areas was small
planting holes filled with small amounts of soil. These were usually less
than that specified for the virgin soil method, one-half or less of recommended
soil volume.
Many small growers return
to a replant field after 3 years. No virgin soil or fumigation is used to
save cost, but the problem persists although the decline varies.
The quality of virgin
soil ranges from poor to questionable to variable. Soil used should be free
of rootrotting pathogens and free of pesticides (herbicides) from previous
agriculture. The growers have to accept that in a culture, there is a minimum
soil volume necessary for starting vigorous papaya plants in order that
these develop into productive trees. This minimum is not being met in the
fields. The essence of the virgin soil method is completely ignored when
vigorous plants are not established.
Although Benlate has
been shown to be somewhat effective, there has not been enough interest
to register the fungicide.
As with Phytophthora
fruit rot, hot water control of anthracnose (Colletotrichum gloeosporioides)
is satisfactory unless high disease incidences are encountered. High disease
incidence also means numerous advanced and deep-seated infections which
escape water treatment. No experimentation on control of deep-seated Stemphylium
and Phoma infections has been performed, but it is expected that similar
situations exist. The importance of field control is underscored by these
findings.
A new class of compounds
called "antipenetrants" has been found to control Colletotrichum
infections on papaya fruits. These compounds are specific inhibitors of
penetrating enzymes called cutinases which the pathogenic fungus uses to
penetrate the fruit in the field. These compounds have broad specificities
and can control a number of cutinases of different fungal pathogens. Because
of their broad enzyme specificity, they can control more than one pathogen
at a time (e.g., Colletotrichum and Phytophthora).
Laboratory studies gave
complete control of infection of anthracnose with antipenetrants. A field
study of two antipenetrants resulted in no significant control of anthracnose
and chocolate spot with sprays every 2 weeks as compared to unsprayed controls.
Despite the lack of statistical significance, chlorpyrifos at 5 uM concentration
has consistently less disease than the controls.
Papaya Ringspot
Papaya ringspot is still
a threat to the industry. The current control program has been successful
in preventing the virus from spreading into the vital papaya-growing area
of Puna. This is due to the ongoing constant vigilance and diligent roguing
program. It is imperative that this program be continued. Stronger regulations
are needed so DOA's efforts will be more effective.
The incorporation of
the enzyme-linked immunosorbent assay (ELISA), a highly sensitive method
to detect the papaya ringspot virus, into the vigilance and roguing program
has been completed.
There is still a danger
that the papaya ringspot virus will become widespread throughout the State.
In anticipation of this occurrence, alternate means of control are being
sought. One method which can be used is to cross-protect papaya plants with
mild strains against the devastating severe strains of the virus. Using
mutagenic chemicals, three mild strains were produced for cross protection,
and these are currently being tested.
Some packing houses
hold back some fruit samples from each grower to test for disease incidence.
Farmers are instructed to improve field practices if diseases are detected.
Field tests are underway
to screen for newer fungicides to replace Mancozeb.
Little is known of the
effects of nematodes on papaya growth.
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Insects
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Aphids
Aphids transmit the
papaya ringspot virus.
Virus cannot be successfully
controlled by controlling the aphid vectors. Therefore, instead of trying
to control aphids, a more adequate control measure for papaya ringspot is
eradication of infected trees.
The seriousness of ringspot
virus must be emphasized, and the control program by DOA must be continued.
Mites
Important mite pests
are the broad mite, flat mite, and spider mite. Flat and spider mites are
serious to growers in dry areas.
Periodical outbreaks
of spider mites on Kauai seems to be effectively controlled by biological
means. Spidermite control with biocontrol agents has been going on for many
years by the DOA. However, the most effective biocontrol agents are ones
that have been long established here. Grower education in recognizing and
learning ways to conserve these predators (through selective use of insecticides
and application methods) are needed.
Importation of mite
predators requires state permits. Experts must inspect and certify all mites
in the shipments to prevent introduction of unwanted predators and pests.
Sulfur is registered
for controlling mites, but can be corrosive on the spray equipment, is slow
acting, and is ineffective under extremely dry growing conditions.
On Kauai, a small black
ladybeetle and a predatory mite appear to control mite and aphid problems
in papayas.
Fruit Flies
The fruit fly is a postharvest and export problem. In September 1984,
ethylene dibromide (EDB) was withdrawn from use as a quarantine treatment
of papayas by the Federal Government. A new system was developed by the
USDA Tropical Fruit and Vegetable Research Laboratory in Hilo. This system
has two equally important components:
fruit selection and harvest interval to minimize fruit fly infestation,
especially larval infestation, and
a two-stage heat treatment or double dip. Fruit ripeness is measured
with a Hunter colorimeter. The treatment procedure accepted by APHIS for
use in September 1984 is as follows:
Papaya selection criteria
Hunter b value
23.4 blossom end
24.4 yellow "hot" spot
Preheat conditions
Temperature Time
42 + 1oC 5 minutes
40 minutes recovery time
Heat conditions
Temperature Time
49 + 1oC 3 minutes
20 minutes recovery time
Maximum time from harvest to treatment is 18 hours.
Two serious problems have been encountered as the result of the new
treatment:
the correct color to use on the yellow "hot" spots, and
the failure of the fruit to soften properly during ripening caused by
overheating during the hot water treatment. Research is underway to seek
solutions to these problems.
Effective April 8, 1985,
the selection criteria has been modified to a Hunter b value of 23.4 at
the blossom end and 27.4 at the yellow "hot" spot, and the preheat
time at 42oC reduced to 30 minutes.
The modified treatment
has resulted in fewer problems. Research is currently underway to improve
upon the hot water treatment and to develop alternative treatments.
Methoprene is an insect
juvenile hormone analogue which regulates insect development and prevents
adult fruit fly development when applied to the skins of infested papaya
fruits. It has been found to be an effective postharvest treatment for Mediterranean
and Oriental fruit flies.
CTAHR is conducting
a study on the role of ethylene as it relates to the hard-fruit problem
of double-dipped fruits.
Methyl bromide (MB)
has phytotoxic effects, but some packing houses would like to see more work
done because there is evidence of promise using high temperatures with low
dosages. No detectable residue were found after proper period of aeration.
Occasional russetting were noticed on the skin, but fruits appeared marketable.
Existing EDB chambers can be easily modified for MB use and fruits can be
1/4 - 1/3 ripe. The chambers have to be loaded with 10-15 lb. of fruits/cu.
ft. to prevent scalding.
Completed studies have
shown that less than quarter-ripe fruits are not infested with fruit flies.
Ripe fruits can be stored at 32oF for extended periods in excess of 2 weeks.
The use of quarter-ripe fruits at harvesting and 10 days at 46o - 48oF may
be an alternative.
Vacuum has been found to be ineffective.
Ultrasound has been
shown to cause complete mortality to fruit fly eggs and larvae. However,
for intensities tolerated by papayas, ultrasound is only active very near
the surface. Therefore, ultrasound without additional treatment is ineffective.
Microwave has been shown
to be effective for inducing complete mortality of both eggs and larvae
in papaya. The microwave heats the inside, and the hot water the outside
to kill fly eggs or larvae. However, the non-uniform heating that occurs
makes industrial application of this treatment process unfeasible at this
time.
Irradiation is a viable
technique for controlling three species of fruit flies at probit 9 security
level with an applied dose of 0.26kGy (26 krad). Several U.S. and Canadian
companies have expressed interest in building papaya irradiators for Hawaii.
The estimated cost for irradiation is $.025/lb. of papaya. House Bill No.
61 of the 1985 Legislature calls for the renewal of radiation technology
by the DOA. FDA is expected to approve the use of irradiation up to 1.0
kGy (100 krad) in the next few months for disinfestation and shelf life
extension of fruits and vegetables.
The economic feasibility
of irradiation treatment to serve Hawaii's papaya industry requires objective
and critical examination. Irradiated papayas are currently not allowed into
Japan. If an irradiation plant were to be built in Hawaii, the industry
would prefer State government involvement rather than private companies.
The location of the facility should involve careful consideration because
of possible community opposition and logistical problems associated with
transporting papayas from growing areas.
Public reaction to consumption
of irradiated food has been studied and found to be related to the level
of understanding of the irradiation process. Research is needed to test
consumer reaction when actually given a chance to purchase irradiated papayas.
Vapor heat treatment
is another disinfestation procedure approved by USDA/APHIS and Japan. One
packing house is planning to use this treatment for its Japan-bound fruits.
Mature green fruits
are most sensitive to chilling and begin to show injury after 10 days at
2oC. Fruits showing 60 percent yellowing can be kept at 2oC for 17 days
without developing injury. Preconditioning, waxing, wrapping, and alternative
temperature did not significantly change the response to chilling temperature.
Current quarantine treatments
are based on the premise that high infestation levels are likely in each
batch of fruit treated and that mortality levels of 99.997% are necessary
for adequate quarantine security.
For a current list of
insecticides registered for use on papaya, the DOA or the University of
Hawaii Cooperative Extension Service should be contacted.
There is a new insect
on Kauai that was first found in 1978, Telostylinus lineolatus (scavenger
fly). However, it has been reported by the DOA that this insect is not considered
a pest of papaya. A University of Hawaii plant pathologist has not found
Phytophthora spores on adult flies, and this insect does not appear to be
involved in Phytophthora outbreaks.
Leafhopper
Leafhopper continues
to be a problem on Kauai and Oahu. The insect causes terminal leaf chlorosis.
Control is by malathion sprays directed at the terminals only. Lower leaves
should not be sprayed to avoid killing predators.
The IPM project has
been terminated. Although insecticide use can be reduced through proper
monitoring, growers still need to spray fungicides as frequently.
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Labor
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Labor housing in the
papaya growing areas on Kauai remains a problem because the Moloaa lease
agreement prohibits housing. Related to the housing problem, farmers have
experienced thefts after working hours when there is no one around to prevent
trespassing.
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Land
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The papaya replant problem
can become a serious disease problem if proper practices are not followed.
In the past when virgin land was readily available, the practice in Puna
was to secure a short-term use for a piece of virgin land, grow one crop
of papaya, and move on to another piece of virgin land. With the current
shortage of virgin land, growers now abandon their fields and return to
replant after 3-5 years.
On Kauai replant fields
are usually fumigated for Phytophthora control.
It costs $400-$600 per
acre to clear replant land in Puna. Land lease is approximately $50/acre
per year.
With the phase-out of
a major sugar producer in Puna, land is no longer a limiting factor for
growth of the papaya industry in the area.
A land classification
study showing land suitable for papaya production is being compiled by USDA-SCS.
Large packing companies
and cooperatives often acquire large tracts of land (500-1,000 acres) which
they distribute to their own growers. Small independent growers often have
difficulty in acquiring land at a reasonable cost. State land planning should
consider the needs of small independent growers.
At Moloaa, Kauai, where
about 700 acres (600+ acres cultivatable) are leased from Amfac, there are
14 years left in the agreement which expires in 1999.
On Oahu real estate
speculation has made agricultural land leases particularly difficult to
obtain. More land is required for new farmers and to expand existing acreages.
Papayas are included
in both the Kahuku and Waiahole Agricultural Parks. The Hawaii Department
of Land and Natural Resources needs to be contacted for more details. Further
agricultural park development is at a standstill pending legislative actions.
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Marketing
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The Papaya Administrative
Committee will spend $287,600 for advertising and promotion efforts in 1985.
The efforts will include:
Active public relations
program involving the consumer and the foodservice industry.
A strong merchandising
program including in-store demonstrations and training of retail produce
managers.
Participation in tradeshows.
Continuing the promotion
programs in Japan in cooperation with the USDA/Foreign Agriculture Service.
Total fresh production
for 1985 is estimated at 48.0 million pounds, a substantial decrease from
the record 64.8 million pounds produced during 1984. Estimated 1986 total
fresh production is expected to increase only slightly to 48.0 - 50.0 million
pounds.
The 1985 production
was affected by many factors:
The record production
levels during 1984 drove farm prices below production cost levels, resulting
in severe economic losses to growers.
As a result of low farm
prices and the uncertainties of the disinfestation conversion to the double-dip
process, growers decreased new plantings.
During the winter months,
packing houses began experiencing a high incidence of hard fruit after the
double-dip treatment. This resulted in severe marketing problems, especially
on the mainland.
The "less than
1/4 ripe" requirement of the new disinfestation process resulted in
heavy culling by farmers and packing houses.
Marketing resources
have been decreased while current industry efforts are aimed at solving
problems related to the new double-dip procedure.
Foreign competition
is begining to be of concern. There is the possibility of the Philippines
supplying papayas to the Japan market. Imports of foreign grown papayas
into the U.S. increased from 1.4 million pounds in 1981 to 4.3 million pounds
in 1984. These papayas come from Brazil, Mexico, and the Caribbean islands
(especially Bahamas).
The U.S. mainland market
potential for papaya nectar:
Projections of the U.S.
mainland market potential for papaya nectar based on test marketing in Portland,
Sacramento, and Phoenix were released by Ibrahim Dik in a 1982 Ph.D. Dissertation
(U.H.). The study indicated a U.S. mainland market potential of 1.4 million
cases of 24 oz. cans of frozen papaya nectar base and 1.2 million cases
of single strength ( hot pack) papaya nectar. The indicated market potential
for these two forms of nectar combined would require 28.2 million pounds
of fresh fruit. This does not include requirements for Hawaii and such as
dairy cartons).
A random sample of 2,630
households in Portland, Oregon provides essential data on the nature of
U.S. West Coast demand for papaya nectar (HITAHR Research Report 221, July
1981). The study indicates various reasons why test market sales did not
attain a higher level, and suggests what could be done through product improvement
and market development to increase the level of sales.
The study indicates
very conclusively that the level of sales correlates in a positive manner
with the level of income, the level of education, travel to Hawaii and consumption
of fresh papaya. Taste was the primary deterrent to repeat purchases, although
the majority liked the flavor. Other reasons were that the product was considered
too sweet and that the test price was somewhat in excess of that for most
competing juice or nectar products. The data further indicate that papaya
nectar is destined to be a very minor juice item unless important breakthroughs
are made in finding a satisfactory natural sweetener, reduction in the degree
of sweetness, improvement in flavor, and some means of reducing costs to
make the price more competitive.
Most Portland respondents
who had consumed papaya nectar liked the flavor and over 90 percent of those
who tried papaya nectar also bought it. Almost 30 percent of those who bought
it consumed it at breakfast time. Use at breakfast time tends to contribute
to steady purchases and reduces seasonality of sales.
The findings should
provide guidelines for more effective and efficient market development for
papaya nectar. Among these would be a greater effort to expose Hawaii visitors
to the product.
Characteristics of consumer
demand for fresh papayas:
A random sample survey
of consumer demand in fresh papayas was conducted in the Los Angeles metropolitan
area during May-June, 1984. This was the major market for Hawaiian papayas
at that time, with sales constituting 40 per cent of all Hawaii papaya marketings
and 60 per cent of marketings shipped outside of Hawaii.
The major finding of
the study was that the majority of respondents who had ever eaten fresh
papayas had bought papayas during the past year. This indicates the importance
of persuading people to try the product.
Although 40 per cent
of the respondents bought papayas for the first time in Los Angeles, those
who had made a trip to Hawaii were more apt to consume and buy papayas in
Los Angeles than those who had not been to Hawaii.
Frequency of purchase
of papayas, although somewhat low, was at a level that might be considered
encouraging for a miscellaneous food product.
Since most respondents
bought papayas on impulse after entering the store, there appears to be
an opportunity to increase sales through greater display and in-store price
specials.
Among the important
characteristics which tended to limit sales of papays were high prices in
relation to other fresh fruits, perceived lack of availability of quality
papayas, and dislike of taste.
Most respondents bought
papayas because of a predetermined image. Store display was indicated to
be a more effective motivation for purchase than media advertising due in
part to the limited amount of media advertising. A visit to Hawaii was also
important in motivating the first purchase of papayas in Los Angeles.
Since only 40 percent
of papayas consumers in Los Angeles had ever eaten papayas at breakfast
time, promotion of papayas as a breakfast fruit might be given more consideration
in market development.
A very predominant adverse
image of irradiation must be overcome if that form of treatment is considered
feasible in other aspects.
The survey points out
a number of important product and demand characteristics which suggest the
need for improvement in harvesting, merchandising, and market development.
Because of the distant
possibility of irradiation being an alternative fruit fly control, a study
was made to determine consumer response to irradiated papayas. An overwhelming
63 percent of Los Angeles respondents indicated that they would not consume
papayas that were known to be irradiated. Seventy-three percent thought
irradiated papays would endanger health, including 7 percent who thought
consumption of irradiated fruit might cause cancer. Ten percent indicated
they needed more assurance of safety prior to consuming irradiated papayas.
Fresh papaya production
in the 1980s shows an increase of 28 percent for 1981 over 1980; a decrease
of 23 percent for 1982 over 1981; a 3 percent increase for 1983 over 1982;
an increase of 45 percent for 1984 over 1983; and using the PAC's projection
of 48 million pounds fresh production for 1985, an estimated decrease of
28 percent for 1985 over 1984.
Fresh papaya prices,
if anything, show a downward trend with prices averaging 25 cents per pound
in 1982; 24 cents in 1983 and 13 cents in 1984. Prices are up in 1985, but
this can be attributed to the short supply of papaya in the mainland and
local markets. Compared to 1984, the market supply of papayas for the first
three quarters of 1985 is down 46 percent.
The PAC has maintained
a promotional program since its inception and over the past four years,
have set aside an annual budget of $250,000 to $300,000 for this purpose.
DOA has contributed $190,000 to their promotional budget over the past four
years.
Before state money is
committed to develop a long term program, the plan to develop this program
should be submitted by industry for review by DOA.
--------------------------------------------------------------------------------
Post Harvest
--------------------------------------------------------------------------------
The industry continues
to be concerned about packaging, packaging systems, and refrigerated containers
as related to diseases and shelf life of export papayas.
The adoption of the
double dip hot water system requires fruits to be treated within 18 hours
of harvest. The packing houses and storage areas are also designed to be
free of fruit flies.
There are indications
that the "hard fruit" problem which plagued the industry could
be at least partially due to poor hot water tank design leading to over
heating of the fruits.
Basic studies on how
respiration, ethylene production, and fruit color changes affects ripening
should be completed. The results could help overcome problems with "physiological"
softening during storage and transit. The problem of hard f ruit following
the double dip treatment illustrates the paucity of information available
on fruit ripening. Limited information is available for 'Sunrise Solo,'
although work is progressing in the 'Kapoho Solo.'
Ripening patterns differ
according to season, variety, growing location, and growing conditions.
(Refer to soft fruit problem under "Practices"). The Hunter colorimeter
is being used to measure and determine maturity; however, a new Minol ta
is being considered as a cheaper alternative.
Under optimum storage
conditions, the maximum postharvest life of the papaya fruit is about 28
days. Retailers prefer ripe fruits on their shelves. Much of the postharvest
problems at the retail shelf have been the result of wholesalers and retaile
rs storing the fruits too long or under wrong temperature conditions.
Waxes help reduce shrinkage
and give a glossy appearance. Papaya packers use Decco 261, which is a formulation
once used by the pineapple industry. Studies are underway with FMC 560,
which seems to produce a nicer gloss.
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Public Policy
--------------------------------------------------------------------------------
There are many public rules, policies, and regulations which put unnecessary
burdens on farmers, e.g., OSHA, EPA.
To minimize passage of new burdensome rules, policies, and regulations,
Hawaii's legislators and congressmen must be informed about farmer concerns.
Efforts should be made to repeal laws that put unwarranted burdens on
farmers.
Recent changes in CAL/OSHA's regulations resulted in several million
dollars of losses for the Hawaii papaya industry.
--------------------------------------------------------------------------------
Publications
--------------------------------------------------------------------------------
AKAMINE, E.K. and ARISUMI, T. 1952. The Control of Postharvest Decay
of Papaya. HAES Progress Notes #082
AKAMINE, E.K. 1980. Evaluation of Papaya Lines and Cultural Practices
at Moloaa, Island of Kaui, Hawaii. CES Cir. #497
ARAGAKI, M. and MURAKISHI, H.H. 1954. Phytotoxic Effects of Fungicides
on Papaya and Passion Fruit. HAES Progress Notes #105
ARAGAKI, M. and NAKASONE, H.Y. 1976. Phytophthora Fruit Rot Resistance
in Certain Papaya Inbred Lines and F1 Hybrids. Research Bulletin #163
ARKLE, T.D. JR. and NAKASONE, H.Y. 1984. Floral Differentiation in the
Hermaphroditic Papaya. HortScience Vol. 19(6): 832-834. Journal Series
#2832.
AWADA, M. and IKEDA, W. 1953. Effect of Moisture on Yield and Sex Expression
of the Papaya Plants (Carica papaya L.) HAES Progress Notes #097
AWADA, M. 1958. Relationships of Minimum Temperature and Growth Rate
with Sex Expression of Papaya Plants (Carica Papaya L.) Technical Bulletin
#038.
CHIA, C.L., NISHINA, M.S. and EVANS, D.O. 1989. Papaya. HCES Commodity
Fact Sheet PA-3(A)
DEDOLPH, R.R. 1962. Effect of Benzothazole-2-Oxyacetate on Flowering
and Fruiting Papaya. Reprinted from The Botanical Gazette, Vol. 124, No.
1, p. 75-78. HAES Tech. Paper #527.
DUERNBERGER, G.W. and SHAW, T. 1952. New Papaya Products. HAES Progress
Reports # 077
HAMILTON, R.A. 1954. A Quantitative Study of Growth and Fruiting in Inbred
and Crossbred Progenies from Two Solo Papaya Strains. Technical Bulletin
#20.
HAMILTON, R.A. 1954. Growth Studies of Papaya Plants on a Tropical Soil
with a Compacted Subsoil. Reprinted from ASHS, Vol. 64, 1954. p. 111-116.
HAES Tech. Paper #312
HAMILTON, R.A. 1956. A Preliminary Report on Effects of Soil Application
of Crag Fungicide 974 on Growth of Papaya Plants. Reprint from Proceedings
of ASHS, Vol. 67, p. 298-301, 1956. HAES Misc Paper #64
HAMILTON, R.A. and ITO, P. 1968. Sunrise Solo a Different Colored Solo
Papaya. HAES Cir. #69
HAMILTON, R.A. 1969. Effect of Location on Size and Quality of Papaya
Fruits. Proceedings of the 5th annual Hawaii Papaya Industry Ass'n. p.
25-27, 1969. CES Misc. Pub. #64
HOLTZMAN, J.J., JONES, W.W. and GALLOWAY, A.G. 1939. Effect of High-Temperature
Sterilization on the Solo Papaya. HAES Cir. #14
ISHI, M., YEE, W. and HOLTZMAN. 1971. Beware Papaya Mosaic Disease. CES
Leaflet # 001
ISHI, M., YEE, W. and NAMBA, R. 1972 revised. Papaya Mosaic Disease.
CES Leaflet #95
JONES, W.W. 1939. The Influence of Relative Humidity on the Respiration
of Papaya at High Temperatures. Reprinted from ASHS Vol. 37. HAES Tech
Paper # 56.
JONES, W.W. 1940. Methyl-Bromide Fumigation of Papaya and Tomato. HAES
Cir. #17
LANGE, A.H. 1960. The Effect of Fumigation on the Papaya Replant Problem
in Two Hawaiian Soils. Reprinted from ASHS, Vol. 75, p. 305-312. HAES
Tech Paper #430.
LANGE, A.H. 1961. Effect of Sarcotesta on Germination of Carica Papaya.
Reprinted from The Botanical Gazette, Vol. 122, No.4, p. 305-311. HAES
Tech Paper #522
LANGE, A.H. 1961. Factors Affecting Sex Changes in the Flowers of Carica
Papaya L. ASHS 77: 252-264. HAES Tech Paper #528.
LANGE, A.H. 1961. Responses of Solo Papaya to Mulching. ASHS 77: 245-251.
HAES Tech Paper #631
LANGE, A.H. 1961. The Effect of 2,3-Dichloroisobutyrate and 2,2-Dichloropropionate
on the Sex Expression of Carica Papaya L. ASHS 78: 218-224. HAES Tech
Paper #632
LANGE, A.H. 1961. The Effect of Temperature and Photoperiod on the Growth
of Carica Papaya. Reprinted by Ecology, Vol. 42, No. 3, p. 481-486 HAES
Tech Paper #633.
MANSHARDT, R.M. and WENSLAFF, T.F. 1989. Zygotic Polyembryony in Interspecific
Hybrids of Carica papaya and C. cauliflora. ASHS Vol. 114(4): 684-689.
Journal Series #3273
MANSHARDT, R.M. and WENSLAFF, T.F. 1989. Interspecific Hybridization
of Papaya with other Carica Species. ASHS Vol. 114(4): 689-694. Journal
Series #3274.
MEKAKO, H.U. and NAKASONE, H.Y. 1975. Floral Development and Compatibility
Studies of Carica Species. ASHS Vol. 100(2): 145-148. Journal Series #1741.
MEKAKO, H.U. and NAKASONE, H.Y. 1975. Interspecific Hybridization Among
6 Carica Species. ASHS Vol. 100(3): 237-242. Journal Series #1761.
MEKAKO, H.U. and NAKASONE, H.Y. 1976. Inheritance of Eight Characters
in Intra- and Interspecific Crosses Among 5 Carica Species. ASHS Vol.
101(1): 14-19. Journal Series #1835.
MEKAKO, H.U. and NAKASONE, H.Y. 1977. Sex Inheritance in Some Carica
Species. ASHS Vol. 102(1): 42-45. Journal Series #1888.
MOSQUEDA-VAZQUEZ, R., ARAGAKI, M. and NAKASONE, H.Y. 1981. Screening
of Carica papaya L. Seedlings for Resistance to Root Rot caused by Phytophthora
palmivora Butl. ASHS Vol. 106(4): 484-487. Journal Series #2450.
MOSQUEDA-VAZQUEZ, R. and NAKASONE, H.Y. 1982. Diallel Analysis of Root
Rot Resistance in Papaya. Reprinted from HortScience Vol. 17(3): 384-385.
Journal Series #2630
MURASHIGE, T., ARAGAKI, M. and KUNISAKI, J. 1964. Growth Inihibition
& Mortality in Papaya Seedlings Resulting from Papaya Tissue Incorporated
in the Soil. Plant Disease Reporter. Vol. 48, No. 1. HAES Tech Paper #664.
NAGAO, M.A. and FURUTANI, S.C. 1986. Improving Germination of Papaya
Seed by Density Separation, Potassium Nitrate, and Gibberellic Acid. HortScience
Vol. 21(6). Journal Series #3019
NAKASONE, H.Y. and STOREY, W.B. 1955. Studies on the Inheritance of Fruiting
Height of Carica Papaya L. Reprinted from ASHS, Vol. 66, 1955. p. 168-182.
HAES Tech. Paper #310
NAKASONE, H. 1966. Papaya Breeding Work at Malama-Ki. Hawaii Papaya Industry
Association Conference Proceedings. p.9, 1965. CES Misc. Pub. #28
NAKASONE, H.Y. and ARKLE, D. JR. 1971. Development of Intra-Ovarian Ovaries
in Carica papaya L. ASHS, Vol. 96(5): 550-553. Journal Series #1279.
NAKASONE, H. 1972. New Papaya Cultivars. Proceedings of the 7th annual
Hawaii Papaya Industry Ass'n. p. 28-30, 1971. CES Misc. Pub. #85
NAKASONE, H.Y., CROZIER, J.A. JR. and IKEHARA, D.K. 1972. Evaluation
of 'Waimanalo,' a New Papaya Strain. Technical Bulletin #79.
NAKASONE, H.Y. and ARAGAKI, M. 1973. Tolerance to Phytophthora Fruit
and Root Rot in Carica papaya L. ASHS, Vol. 17: 176-185. Journal Series
#1623.
NAKASONE, H.Y., YEE, W., IKEHARA, D., DOI, M. and ITO, P. 1974. Evaluation
and Naming of Two New Hawaii Papaya Lines, 'Higgins' and 'Wilder'. HAES
Research Bulletin #167
NAKASONE, H.Y. 1975. Papaya Development in Hawaii. HortScience Vol. 10,
No. 3, p.1. Journal Series #1865.
NAKASONE, H.Y. 1976. Breeding and Disease Problems in Some Tropical and
Subtropical Fruits with Emphasis on Papaya. Acta Horticulturae 57, p.
125-133. Journal Series #1973
NAKASONE, H.Y. 1979. Current Status of Breeding for Papaya Virus Resistance.
p. 12. 15th Annual Hawaii Papaya Industry Ass'n. Conference. CES Misc.
Pub. #178
NAKASONE, H.Y. and LAMOUREUX, C. 1982. Transitional Forms of Hermaphroditic
Papaya Flowers Leading to Complete Maleness. ASHS Vol 197(4): 589-592.
Journal Series #2639
NISHIMOTO, R.K., ZANDSTRA, B.H. and KRATKY, B.A. 1973. Herbicides for
Papaya. Journal Series #1672
NISHIMOTO, R.K. 1979. Status of Weed Control in Papayas. p. 16. 15th
Annual Hawaii Papaya Industry Ass'n. Conference. CES Misc. Pub. #178
NISHIMOTO, R.K. and CHIA, C.L. 1986. Weed Control in Papaya. HITAHR BRIEF
#058.
ROMANOWSKI, R.R. JR., CROZIER, J.A. JR., ITO, P.J. and TANAKA, J.S. 1972.
Herbicide Selectivity Trials with Papayas (Carica papaya) in Hawaii. HAES
Research Report #181
SHOJI, K. 1951. Storage Studies of Vapr-Heat and Ethylene-Dibromide Treated
Papaya. HAES Progress Notes #067
SHOJI, K., NAKAMURA, M. and MATSUMURA, M. 1958. Growth and Yield of Papaya
in Relation to Fertilizer Applications. HAES Progress Notes (Station Prog.
Report) #118
STOREY, W.B. 1938. Segregations of Sex Types in Solo Papaya and their
Application to the Selection of Seed. Reprinted from ASHS, 1938. p.83-85.
Haes Tech Paper.
STOREY, W.B. 1938. The Primary Flower Types of Papaya and the Flower
Types that Develop Them. Reprinted from ASHS, 1938. p.80-82. HAES Tech
Paper
STOREY, W.B. 1972. Why Papaya Trees Fail to Fruit. CES Cir. #339
YEE, W., AKAMINE, E.K. and AOKI, G.M. 1970. Papayas in Hawaii. CES Cir.
#436
YEE, W., SHIGENAGA, R. and AWADA, M. 1972. Papaya Nutrition Practices
Past and Present. Proceedings of the 7th annual Hawaii Papaya Industry
Ass'n. p. 17-20 1972. CES Misc. Pub. #85
YEE, W.Y.J., SEKIOKA, T.T., NAKASONE, H.Y., IKEHARA, D., OOKA, J., and
AKAMINE, E.K. 1980. Evaluation of Papaya Lines and Cultural Practices
at Moloaa, Island of Kauai, Hawaii. CES Cir. #497
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Seasonality
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It is not likely that
technology can be developed to allow trees to produce at the same level
throughout the year.
Marketing strategy is
geared to the July to December period.
A viable processing
industry will contribute to the solution of the supply problem.
Rainfall seems to be
a factor in the seasonal variation of production. Irrigation would tend
to even out the two peaks in production.
Using long term storage
(up to 6 weeks) to even out variations in supply is not possible with present
technology.
Objective yield functions
have been developed to forecast supply 4 months ahead of time with a 95%
accuracy. This Hawaii Agricultural Reporting Service program must be continued.
The yield forecasts are used to properly time promotion programs and in
many other planning activities.
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Transportation
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Any breakdown in the
total transportation network would affect the papaya industry severely.
Fifty per cent of the export is transported by air (out of Honolulu) and
the other fifty per cent by surface. Because of the limited air capacity,
any addi tional transportation needs will have to be handled by surface
carriers.
United Airlines is currently
the only regularly scheduled passenger carrier flying from Hilo to the mainland
(with three flights a week). Their DC-8's are not capable of carrying cargo
containers.
The transshipment of
papayas through Honolulu to the export market adds to the transportation
costs of the industry. Fruits for transshipment are brought to Honolulu
either by Young Brothers barge in 20-foot reefer containers or by DHL planes.
Thos e destined for the mainland market are loaded into LD-3 containers
for air freight (several carriers) or into 24-foot reefer containers for
surface freight (Matson). Matson has no direct service out of Hilo.
It takes the papayas
from 7 to 10 days to get from Hilo to the West Coast, depending on the shipping
schedules.
Papayas from Kauai are
barged to Honolulu twice a week through Nawiliwili.
Surface capacity appears
adequate, but air lift capacity remains inadequate. The ideal situation
would be for the papayas to be shipped directly from Hawaii or Kauai to
their export destination without having to be transshipped through Honolulu.
Interisland air freight
is expensive. Interisland barge holiday schedules continue to be unsatisfactory.
Existing equipment is old and there are inadequate refrigerated containers.
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Water
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The supply of water
in the Moloaa area is adequate for current needs. In 1984 farmers paid an
average of $0.33/1,000 gallons for irrigation water. The high for the year
was $0.84/1,000 gallons. This is considered expensive by Kauai growers.
In com parison, domestic water costs less ($0.28/1,000 gallons). The high
cost is due to the cost of electricity used to pump the water.
Papaya farms on the
Big Island are grown without irrigation. It would cost approximately $150,000
to drill a well in Kapoho, but the water would be brackish.
Oahu growers using county
water pay $0.84/1,000 gallons if below 13,000 gallons, and $0.69/1,000 gallons
if above 13,000 gallons.
Irrigation experiments
were conducted in Puna from 1977-82. The long term results did not show
any significant advantage to be gained in using irrigation except during
periods of severe droughts. The benefits gained during periods of severe
drought s should be balanced against the cost of building an irrigation
network in the district.
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Weeds
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Weeds compete with papaya
for water and nutrients, reduce yields, affect harvesting efdiciency, and
as host plants, may play a role in disease and insect control.
Currently, paraquat
(Paraquat+Plus, Gramoxone), dalapon (Dowpon M), and glyphosate (Roundup)
can be used postemergence in papaya. Certain species like guava are difficult
to control with Roundup.
Diuron (Karmex) is the
only preemergence material registered and its use in orchards is limited
to trees established in the orchard for at least 1 year. Diuron is mainly
effective on annual weeds. Additional preemergence herbicides to complement
diu ron activity in regard to weed spectrum and time of application would
be useful for papaya production.
Research and residue
analysis for Surflan in papayas was completed 2 years ago, and the petition
for registration was also completed by IR-4. However, it appears that Elanco,
which manufactures Surflan, may not support its registration. As of appro
ximately September 1, 1985, Elanco informed IR-4 that they are not interested
in supporting any minor use registrations.
It would be desirable
to conduct studies on mulching to control weeds.
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Green - Seeds Co., Ltd.
81/10B Ho Van Hue Street, Phu Nhuan District, Ward 9, Ho Chi Minh City, Vietnam
Tel: +84 (8) 847 6901 - Fax: +84 (8) 844 1392 - Email: info@green-seeds.com
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