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Tomato Cost Analysis File
Dr. Kent Fleming, Agriculture and Resources Economics Dept., CTAHR, (808-322-9136), developed this program to help farmers determine their costs and profits. You will need a spreadsheet program such as Lotus 1-2-3, Microsoft Excel, etc. to run the cost analysis file.
Flowering and Fruiting
The tomato is self-pollinated. Flowers are born in clusters, located on the stem between the nodes. Tomato is sensitive to high night-time temperatures, especially the large fruited fresh varieties. High night-time temperatures may lead to lower fruit set or to small, seedless fruit development. Optimum temperature for fruit set is 60-70F (15-20C).
Fruits reach the mature green stage about 27 days after fertilization. Environmental stress, such as poor nutrition, unfavorable weather, or insect and disease pressure may result in abscission during or after flowering.
Training.
Staked tomatoes provide ease of harvest and higher fruit quality. The trellis keeps the fruits off the ground and results in less soft rot incidence. Stakes 50 inches long are driven into the ground halfway between each plant or in alternating plants 2-3 weeks after transplanting. Training of the plants by tying the plants with plastic twine beginning 3-4 weeks after transplanting is repeated 3 or 4 times during the growing season. The twine is run around each stake and on both sides of the plant to provide vertical support. Before re-using, stakes should be sterilized by steaming 1-2 hr at 200F below a plastic tarp, or with methyl bromide fumigations.
Irrigation.
Drip irrigation for tomatoes has gained popularity because of an increased water use efficiency, and due to the ability to apply fertilizers and pesticides with the irrigation water. With drip irrigation it is possible to closely synchronize weekly water and nutrient application rates with the corresponding stage of crop development.
Introduction
Tomato yields may be reduced by a myriad of insects pests and diseases. The best approach to manage disease and insect pressure is to follow an integrated management approach. The IPM approach is based on proper pest identification, periodic scouting, and the application of pest management practices during the precise stage of the crop's development where no control actions would result in significant economic losses.
Two additional strategies of an integrated management approach consist of 1) Taking pest control actions during the most vulnerable stage in the pest's life cycle (to maximize results with the least possible effort), and 2) To utilize synthetic pesticide spray applications for pest suppression, only after all other pest control alternatives have been considered and exhausted.
Alternative pest controls include those basic "old-time" practices such as rotation, sanitation, the use of disease resistant varieties, and other biological controls. The main objectives of utilizing alternative pest controls over pesticide treatments, is to reduce the high capital costs incurred with frequent pesticide applications, and secondly to maximize the abundance of beneficial organisms.
Bacterial canker
Cornybacterium michiganense can be a serious disease in tomato because it can persist in the soil for many years, and because it is seed transmitted. Symptoms include wilting and cankers on stem and fruits. For control use disease free or certified seed. Contaminated seed may be treated with the following treatments:
Xanthomonas campestris pv. vesicatoria may become a problem during wet weather. Both foliage and fruits are affected. Infection occurs through natural leaf openings or through wounds in the fruit. Fruits show numerous 1/8 inch spots. Leaves show irregularly shaped, brown spot lesions. Destroy tomato plants after harvest.
Bacterial wilt
Pseudomonas solanacearum is the most serious disease of tomatoes in the tropics and sub-tropics. Symptoms include rapid wilt and death of the entire plant without any yellowing of the leaves. If the stem is cut, a gray-brown bacterial ooze is visible. The disease is difficult to control because it remains in the soil for many years. Contaminated fields should be rotated with non-solanaceous crops. Prevent machinery and field personnel from moving from contaminated to non-contaminated soils. The disease penetrates the plant through wound openings in the roots. Old cultivars developed by the University of Hawaii College of Tropical Agriculture and Human Resources Kewalo and BWN-21s are highly tolerant to bacterial wilt.
Blossom-end rot
This physiological disease may cause severe yield reductions in tomato. Initial symptom in the stylar end of the fruit is a slight discoloration appearing water-soaked. The lesions enlarge and turn dark brown or black. An irregular water supply compounded with a fast growing crop may promote blossom end rot. The disease results from a calcium deficiency in the fruit. Calcium is translocated in the plant via the transpiration flow. As a vascular system sink, leaves obtain the primary source of calcium, and when calcium deficiencies occur, fruits will be the first organs to show deficiency symptoms. Factors which have an effect on the plant's calcium supply should be monitored including cultivar, plant nitrogen status, and soil fertility, pH, and an even moisture supply in the root zone. Nitrogen over-fertilization may accentuate blossom end rot by promoting excessive shoot growth.
Blotchy Ripening or Gray Wall
This physiological disease also called internal browning is characterized by irregular browning on the side walls of the tomato. The fruits will develop a normal red color except in the affected areas. A cross-section of affected fruits will show brown veins with yellow to gray cells in the blotched areas. The incidence of blotchy ripening is increased with TMV infection, succulent growth, low potassium, and sudden temperature changes. Commercial cultivars have good resistance to this disease.
Catface
A physiological disorder in which fruits show extreme malformation and scarring at the blossom ends. Catface results from any growth factor that affects normal pistil development in the flower. Prolonged heat during blossoming and other stress factors may result in catfacing. Most commercial varieties are not affected by catface. When possible, remove affected fruits as early as possible.
Double Streak Virus
This disease is normally a combination of TMV and potato virus X or Y. Initial symptom is light green mottling of leaves followed by development of small grayish-brown spots on leaves. Later, brown spots occur on stem and leaf petioles. Infected plants are stunted and fruits, if produced, are covered with dark spots. The virus complex is transmitted mechanically. Controls include growing TMV resistant cultivars, and the use of ground culture determinate cultivars.
Early blight
Symptoms of the fungus Alternaria solani are concentric markings of dead tissue on leaves and stems, as well as spotting on leaves and fruits. The disease can result in crop defoliation during wet and warm weather, at any time during the crop cycle. Controls include a three-year rotation, planting on wide, high beds, and fungicide treatments.
Fruit cracks
Three common types of physiological cracks make fruits unsalable, and permit the entrance of secondary disease organisms.
Cracking can be partially controlled by providing an even moisture supply, thus preventing alternating stages of fast and slow fruit growth.
Fusarium oxysporum f. lycopersici is a soil-borne fungi which enters the plant through the root and plugs the plant's vasular system, stopping the transpirational flow. As a consequence lower leaves are first affected, turning yellow and withering. The symptoms progress and eventually the entire plant is affected, with a dark-brown discoloration in the bark of affected areas, and with only leaves near branch tips remaining alive. Commercial cultivars are available with resistance to races 1 and 2. In addition, sanitation, rotation with grass crops, soil fumigation, and soil pH near 6.5 should be used for control of races 1,2, and 3.
Gray Leaf Spot
Stemphylium solani begins as small circular sunken brownish lesions with spots surrounded by yellow halo. The fungus is favored by hot weather, and can cause severe defoliation in susceptible cultivars. Best control is achieved with resistant cultivars. Destroy the tomato crop after harvest.
Late blight
Phytophtora infestans causes severe defoliation, stem girdling, and destructive rot of fruits. Cool nights and warm days with abundant moisture favor development of this fungus. Fruit symptoms include irregular watersoaked spots on which turn brown and wrinkle the surface. Control includes careful monitoring with fungicide applications.
Puffiness
This physiological disorder is common during the winter or early spring. Affected fruits are light and feel soft. Fruit shape is normal but the surface is flattened or shrunken over the sections between the internal walls. Fruit cross-sections show a normally developed outer wall and poorly developed seed locules, with existing cavities between the locules and the outer wall. Factors which may promote puffiness include poor pollination, excessive N applications under cloudy weather, excessive irrigation, and temperature extremes.
Sclerotinia
Sclerotinia sclerotiorum can cause serious losses in both tomato greenhouse and field operations. The fungus attacks the main stem at the soil line and is characterized by watersoaked areas which become light to dark brown. Further disease development results in wilting and plant death. Masses of white mold and sclerotia are identifying characteristics. High moisture and temperatures promote disease development. Control with proper sanitation, soil drainage, crop rotation with grass crops, and fungicide applications.
Spotted wilt virus
Tomato plant growth ceases and senescence is promoted after infection with spotted wilt virus. In older plants, leavesnear the growing tips show dark, bronze or purplish, circular necrotic spots. Fruits also show circular concentric marks. Tomato spotted wilt virus is the only virus known to be transmitted by thrips. The only effective means of control are resistant cultivars. Celebrity, the standard tomato cultivar in Hawaii is highly susceptible to the new strain of spotted wilt. Currently PetoSeed cultivar PSR 55289 has shown resistance, and comparable horticultural traits to Celebrity.
Tobacco mosaic virus
Symptoms include mottling or mosaic effects on the leaves. Yields will be reduced significantly with viral infections during the early crop stages. The virus is transmitted by mechanical means, including pruning, staking, and by field workers. Several com mercial varieties are resistant to tobacco mosaic virus.
Soil Acidity
Optimum pH is 6-6.5. Liming to raise the pH to 6-6.5 may aid in reducing fusarium wilt in the field.
Nutrient Rates
Fertilizer applications should be based on crop nutrient demands and on stage of crop growth. Tissue and soil analysis will help to determine how much fertilizer to apply, to complement the nutrient levels already available in the soil. Excessive fertiliz er application, above crop needs, may result in salt buildup, phytotoxic effects on plant growth, ground water contamination, and capital losses due to purchase of unneeded fertilizer. Recommended rates for Hawaii are 1,500 to 2,000 lb/Ac of 10-20-20 or s imilar type fertilizer, with half applied at planting and the remainder 4-5 weeks later. Supplemental 100 lb/Ac of Urea or 200 lb/Ac of sulfate of ammonia applications (lbs/acre) can be applied every 3 to 4 weeks after harvest begins. Phosphorus is an imp ortant nutrient for root development and to hasten fruit maturity.
On soils which test low for phosphorus apply 1,000 lb/Ac of treble superphosphate. This is preplant applied in 30 cm bands in the plant row worked to a depth of 15-30 cm. Soil magnesium deficiencies are corrected with 150-200 lb/Ac of magnesium sulfate. M inor crop Mg deficiencies may be corrected as needed with magnesium sulfate sprays of 10 lbs/100 gallons of water per acre.
An adequate calcium supply is necessary to prevent blossom-end rot in tomatoes. Calcium deficiencies are corrected with weekly foliar calcium nitrate or calcium chloride applications at rates of 10 lb/100 gal and 5 lb/100 gal respectively.
Placement
In non-mulched crops, apply all P and up to 1/2 of N and K prior to planting, incorporating with disks or rototilling. Supplemental fertilization during the growing season should be banded on both sides of the row.
For drip irrigated crops apply all phosphorus and micronutrients and 20% to 40% of total N and K prior to laying the plastic mulch. The remaining N and K is applied at levels corresponding with the crop developmental stage. At the seedling stage apply wee kly 2-5% of the total N and K requirements. At the early fruiting stage begin weekly applications of 10% of the total N and K requirements.
Nutrient Tissue Analysis
To maintain a diagnosis of the crop's nutritional status, and a historical record of crop performance year after year, conduct periodic leaf tissue analysis. The tissue analysis should be calibrated with soil fertility levels, according to soil samples taken before planting. For tissue analysis collect a young mature whole leaf (petiole and leaflets),located below the last open flower cluster. Recommended optimum ranges for tomato are:
Nutrient Range Target Level N 3.0-5.5% 3.0% P 3-1% 0.5% K 3.0-7.0% 3.5% Ca 1.0-5.0% 1.2% Mg 0.40-1.5% 0.4% Fe 100-250 ppm 120 ppm Zn 25-150 ppm 25 ppm Mn 40-300 ppm 75 ppm Cu 5-25 ppm 10 ppm B 25-100 ppm 25 ppm Mo 0.15-5.0 ppm 0.16 ppm
Washing tomatoes
Water for washing tomatoes should be at or above the temperature of the tomatoes. Water with cooler temperatures will be absorbed by the fruits. Washing water management practices should be an important consideration during the handling process, to preven t the spread of post-harvest diseases. Decayed fruit should be removed from the handling process, to remove any potential sources of inocolum. Washing water is chlorinated at 150 ppm and fruits are maintained in this water for no longer than 2 minutes in a single layer of floating tomatoes.
Presizing, Sorting and Sizing
Tomatoes with a diameter of less than 2 inches are placed in the cull section. This operation is carried through an automatic pre-sizer in large commercial operations. Sorting and grading is conducted visually in the packinghouse by separating tomatoes ba sed on USDA color stages. This operation takes on a double effort when sorting out tomatoes with irregular ripening symptoms brought about by whitefly (Bemicia tabaci) feeding on the crop during the growing season. Larger commercial operations in the main land are moving toward the use of automatic electronic color sorters such as the ones developed for apples. Tomatoes are then sized based on market classifications and conveyed to the packing line. Tomatoes are normally packed in 25 lb cartons and unitize d in 2000 lb pallets.
Ethylene treatment
In Hawaii some green picked tomatoes are treated with ethylene to enhance and promote ripening uniformity. Some growers have moved to ethylene treatment to overcome the irregular ripening caused by the sweetpotato whitefly. However, preliminary research c onducted at the University of Hawaii College of Tropical Agriculture and Human Resources did not show improved ripening uniformity with ethylene treatment, but instead indicated the need to improve harvesting techniques and improved training of the harves ting crew to pick fruit at the same stage of physiological maturity. Optimum ripening is obtained when the ripening rooms are maintained at 68F and 90-95 relative humidity at ethylene concentrations of 150 ppm. Ethylene is normally applied with on-site c atalytic generators or with flow-through systems.
Storage
Maintain stored tomatoes at temperatures above 55F (13C). To delay ripening of tomato at a particular stage place in the holding room below 68F (20C). Chilling injury occurs below 50F (10C).
Packaging
Mature greens are sold in 25 lb bulk-packed cartons. Fruits are packed on each carton based on fruit number per row and column in a two layered tomato package. Pick and vine-ripe tomatoes are packed in two-layer lug or tray packs. Cherry tomatoes are pa cked in flats holding 12 1-pint boxes. Plum tomatoes are preferably packed in quart boxes, 8 per carton.
Time to First Harvest
Time from transplant to first harvest is 70 to 75 days for cherry types, 75-80 days for the plum types, and 80-90 days for the large fruited type tomatoes.
Production yields
Ground culture in Hawaii: 20,000 lbs/Acre
Pruned and staked culture in Hawaii: 30,000 lbs/Acre
Average Florida yields: 30,000 lbs/Acre
Average Ohio yields: 13,500 lbs/Acre
Maturity
Tomato fruits mature about 25-30 days after fertilization. Maturity is correlated with increased fruit size, weight, specific gravity, total acidity, and hydrogen concentration. Fruit categories sizes for tomatoes are large 205 g, medium 150 g, and small 115 g. Harvesting stages for tomato include immature green, mature green, turning, half-ripe or pink, and ripe, or red-ripe. Indices of maturity for green picked tomatoes include 1) size, which varies with cultivar; 2) rounded shape, not angular; 3) a whi tish green color development in the blossom end; 4) development of a browny corky tissue on the stem scar of some cultivars, and the preferred method of choice: 5) a representative sample of the fruit's internal appearance (a destructive test). Both cherr y and plum tomatoes are normally picked vine ripe.
Harvesting operation
Fresh market tomatoes are hand picked in 40-50 lb buckets and placed in bins, where a truck takes them to the packing shed. An alternative harvesting operation consists of a conveyor belt on ground tomatoes. Pickers travel a few feet to the conveyor where the tomatoes are placed and conveyed into the loading truck. Bruising of tomatoes from excessive handling and unloading is significantly reduced with the conveyor belt harvesting technology. Tomatoes should be maintained under the shade until taken to th e packinghouse where they are washed, presized, waxed, sorted, graded, sized, packed, unitized for shipment, and shipped to its destination market.
Introduction
Tomato yields may be reduced by a myriad of insects pests and diseases. The best approach to manage disease and insect pressure is to follow an integrated management approach. The IPM approach is based on proper pest identification, periodic scouting, and the application of pest management practices during the precise stage of the crop's development where no control actions would result in significant economic losses.
Two additional strategies of an integrated management approach consist of 1) Taking pest control actions during the most vulnerable stage in the pest's life cycle (to maximize results with the least possible effort), and 2) To utilize synthetic pesticide spray applications for pest suppression, only after all other pest control alternatives have been considered and exhausted.
Alternative pest controls include those basic "old-time" practices such as rotation, sanitation, the use of disease resistant varieties, and other biological controls. The main objectives of utilizing alternative pest controls over pesticide treatments, is to reduce the high capital costs incurred with frequent pesticide applications, and secondly to maximize the abundance of beneficial organisms.
Insects
Important insect pests of tomato include aphids, thrips, leafminers, whiteflies, russet and red mite, cutworms, flea beetles, pinworm, fruitworm, and melon flies. Outbreakes of the sweetpotato whitefly, Bemicia tabaci, and perhaps related sweetpotato whitefly strains is currently a major problem for tomato production in Hawaii. Apply insecticides only when necessary, and when possible rotate pesticide families to reduce the possibility of insect resistance. Insects with exploding population growth rates such as thrips, whiteflies, mites, and aphids are especially prone to develop pesticide resistance, when exposed to frequent applications of the same chemical.
Aphids
Aphids feed on plant sap with sucking mouth parts. Intensive feeding may result in reduced plant vigor. Aphids may also act as vectors of plant viruses, and may also introduce toxins into the plant, resulting in growth deformations. Timely insecticide applications may effectively place in check growing aphid populations.
Cutworms
This caterpillar pests which include the variegated cutworm, Peridroma saucia, and the black cutworm, Agrotis ipsilon, can be devastating on young tomato plantings, by chewing through stems at the soil line. Cutworm activity is greater at nighttime. Control is warranted when high populations occur in the field before planting tomatoes. Baits containing Bacillus thuringiensis are available for cutworm control. Control is normally not recommended when the plants are 1 foot tall.
Fruitworm
The larvae of the fruitworm, Heliothis zea, eats into the green fruit. Heliothis zea is also an important pest of corn, lettuce, beans, and other crops. Eggs are laid singly on leaflets close to small fruits. The larvae eats into green fruit, and when mature burrows into the soil for the pupation stage. The pupa is formed in a tiny cell 2 inches below the soil surface. Adults concentrate their activity at dusk and night, and begin laying eggs after 48 hours. Complete foliar insecticide applications should targe eggs and newly hatched larvae before larvae bores into the fruit and damage occurs. Important natural enemies of the fruitworm include the parasitic wasps Trichograma spp., and Hyposoter exiguae as well as some insect predators.
Leafminers
Leafminers may be serious pests in tomatoes. These are small larvae which drill trails beneath the leaf epidermis as they feed. Because contact insecticides won't reach the larvae, systemics are recommended. Parasites may maintain leafminer populations below damage thresholds under the proper environmental conditions. Parasite populations, however, are normally low in fields which experience frequent scheduled pesticide applications.
Melon Fly
The melon fly has long been a major pest of tomatoes in Hawaii. The pest has traditionally been controlled in problem areas with malathion baits, and with malathion treatment of corn border rows. Remove infected fruits from the field to reduce insect numbers.
Mites
Population explosions of spider mites, and the tomato russet mite, Aculops lycopersici, may occur during hot and dry weather. These tiny insects feed preferentially in the lower stem, and then move on to feed on the upper section of the plant and on leaves. Their life cycle, egg hatching, and two nymphal stages until maturity, lasts one week in hot weather. Presence of the mites is manifested in the bronze and greazy apperance of stem and leaves. Sulfur dust, wettable powder sulfur, and other miticides are effective on mites.
Thrips
The western flower thrips, Frankliniella occidentalis, is a vector for the tomato spotted wilt virus, resulting in dramatic decreased tomato acreage in Maui over the past few years. Thrips may also reduce plant vigor when feeding on tomatoes in large numbers.
Whiteflies
Recent sweetpotato whitefly, Bemicia tabaci, outbreaks have caused considerable losses in tomato fields state-wide. The main symptom is the irregular ripening on the fruits, which is difficult to distinguish on green-ripe tomatoes. The irregular ripening symptoms which are probably caused by a toxin injected by the whitefly, are visible only after ripening, when tomatoes have normally already reached the wholesaler.
Additional sorting operations, and an in-house ripening step may be required to reduce the numbers of poorly ripened fruit in the shipments to market. Full canopy coverage with insecticide sprays is necessary to reach the eggs and adults on the abaxial side of the leaves. Area-wide control strategies may be necessary in areas where whitefly numbers are abnormally high. The sweetpotato whitefly transmitted gemini virus, which has resulted in stunting and reduced fruit size in Florida and California, has not yet been detected in Hawaii.
The common whitefly is the greenhouse whitefly, Trialeurodes vaporariorum, which does not normally reach damaging levels on the field. Parasitic wasps, and predators such as minute pirate bugs and lacewing larvae help to keep the greenhouse whitefly below damaging levels. Tomatoes can sustain greater population levels of the greenhouse whitefly without yield reductions. Control strategies will therefore vary depending on the specific whitefly species in the field. Before conducting and pest control measures, identify which whitefly species is actually present in your field.
The tomato, Lycopersicon esculentum, is the most popular vegetable crop in Hawaii in terms of popularity and in market value. This unique vegetable,a member of the Solanaceae Family along with the peppers and the Irish potato, is a native of Central and S outh America. It is a warm season crop grown from sea level up to 6000 feet in elevation.
In 1991 14 million pounds (6,400 MT) of tomatoes were consumed in Hawaii of which 23% was produced locally in 95 hectares. The farm value of local production of tomatoes in Hawaii for 1991 was about $3 million, with production concentrated in Kona, Mt. View, Kula and Molokai. Local production has decreased substantially over the past few years due to crop losses caused primarily by the tomato spotted wilt virus.
Introduction
In typical commercial operations, tomatoes are grown in polyethylene-mulched beds with a drip irrigation system. Irrigation and fertilization can be monitored closely with a drip irrigation system. The plastic mulch helps to maintain a high degree of wat er and fertilizer use efficiency. Wind break your crop in wind-prone areas with willy willy, sugarcane, or other shrubs suitable to your area. An in-field rotation may be conducted for the following crop by rototilling the row where the windbreak was grow n and planting in the row and preparing the bed in that area.
Time to plant.
In Hawaii tomatoes are grown year round at 300 to 1,000 m elevation; March through August at 1,000 to 1,500 m; September through May from sea level to 500 m elevation.
Field preparation.
Plow and disk to bury the old crop. Liming, when necessary is broadcasted before bedding, fumigating, and pre-plant fertilization.
Propagation.
Tomatoes are normally transplanted in Hawaii to assure proper field establishment. Seedlings are transplanted 3 to 5 weeks after sowing. About 1 oz of seed is needed per acre if seed is transplanted, and 2 lbs per acre if direct seeded.
Spacing.
Spacing for ground or unstaked tomatoes is 5-7 feet between rows, and 3-4 feet in the row. Spacing for pruned and staked tomatoes is 4-5 ft between rows and 15-24 inches between plants.
Transplanting
Seedlings are grown in containerized trays. Containerized transplants are placed in the field with the growing medium attached to the root system. Early root development may be enhanced with 10-52-17 fertilizer solution applications of 3-4 lbs per 50 gal lons of transplant water. Transplants are grown in the multi-cell or tray pack system. A plastic or styrofoam cell surface area of approximately 2 square inches (5 sq cm) is optimal for tomato transplants. The transplants are kept in a greenhouse or shade house. Follow proper sanitary conditions by using sterile trays and soiless growing media. The seedling should be carefully monitored to maintain proper watering, nutrition, and disease-free material.
An integrated management approach should also be employed to tackle weed competition in tomato production. The IPM program for weed control will also rely on weed identification, monitoring, sanitation, alternative cultural practices, and timely herbicide applications. A weed map for each field will serve helpful in the design of weed control measures, and also as a record to provide a field history of weed problems in each field for tomato production.
Cultural control practices for weed control include shallow cultivation, plowing, disking, hoeing, crop rotation, cover cropping, living-mulches, organic or plastic mulching and herbicices. The benefits of proper field preparation can not be overemphasized to improve tomato growth and also to minimize weed problems during the crop growth cycle. Useful crops for rotation with tomato include alfalfa, sugarbeets, and onions. Solanaceous crops such as potatoes and pepper are not recommended as rotation crops.with tomato.
Problem weeds in tomatoes include perennials, dodder, weeds of the nightshade family (solanaceous family), and grasses.
