Morphology

Anthurium is one of the important economic flowers of export potential. There are more than 500 species and several varieties. Few of them are commercially important. Anthurium andreanum, A. veitchii and A. scherzerianum are the economically viable species. Many of them are partially epiphytic in growth habit. Plants prefer to grow under shade. The tolerable level of light in the tropical region during summer is 20-30 per cent. Excess light causes yellowing and scorching of leaves. Very low light intensity causes excessive vegetative growth and low flowering. It is preferable to grow anthurium in the open, under artificial shade structures for better growth and yield. Plant prefers to grow under a relative humidity of not less than 60 per cent and a temperature of not more than 30°C.

Selection Criteria for Planting Materials

Selecting for high yield, disease resistance, and flower characteristics remain as important objectives for the breeding program.Two selections, UH721 (large bright red, anthracnose resistant) and UH712 (red tulip type), were distributed to cooperating growers for advance testing. Tissue cultured plantlets of UH711 (large white, moderately resistant to anthracnose), UH798 (splash, anthracnose resistant), UH862 (white obake, anthracnose resistant) and UH927 (dark red, anthracnose resistant, exceptional yield) were transferred to the Beaumont Research Center for eventual advance testing with cooperators.

Varieties

For internal market, a mixture of many types and colours may not pose much problem, but for exports uniformity in all respects is required for each package.
A good variety should have bright, clear coloured, showy heart shaped spathe with plenty of blisters and symmetrical overlapping of basal lobes. The spadix should be reclining to the spathe at less than 30 and shorter in length than the spathe. An erect flower stem having about five times length of the spathe is considered to be a good character. The plant should be compact and produce suckers profusely. The economic varieties suitable for Kerala condition are Can Can, Mia, Excellent, Tropical Red, Agnihotri, Hawai Orange, Acropolish White, Pistashi, Dragon tongue, Rosata, Senator, Vogue, Jewel, Amigo and Vesuvious Red.

Plantation

The most common method of propagation is by stem cuttings. Top portion of the stem with a few roots is removed and planted. The remaining part of the stem develops side shoots (suckers). By repeating this, additional plants can be obtained. But this propagation method is slow. Tissue culture provides a more rapid method of multiplication. When suckers grow to 4-5 leaf stage with 2-3 good roots, they are separated and planted.
Growing plants from seeds is a lengthy process. The seeds germinate within 6-8 days and are ready for transplanting after 4-6 months. Such plants take about two years to bloom. The plants developed from seeds also show some variability.The plants are watered twice daily during summer months. Mist or overhead sprinkler irrigation is the best. Nutrition It is better to apply the nutrients in smaller dose at frequent intervals than giving larger doses at longer intervals. Manurial applications in soil are given every alternate month. A combination of organic manure such as farm yard manure with about 2 g of 17: 17: 17:2 of the NPK and Mg/plant once or twice a month is applied by many growers. For plants growing in pots 5g complex fertilizer dissolved in 500 ml water is given to the medium once in two months. Foliar spray of 0.5-1.0% of 17: 17: 17 complex could also be given to the plants at biweekly intervals. Deficiency of calcium can cause fading of the spathe colour and so 5 g Ca/plant per month is recommended.

Water Management

Drip or sub-irrigation is recommended for Anthurium production. Do not allow fertilizer to splash onto the foliage, as it will leave a grey residue. The optimal temperature for Anthurium growth is 70 to 90°F. Keep air temperatures above 55°F, otherwise visible or invisible damage may occur, and plant growth will be delayed when temperatures return to appropriate levels.

Nutrient Management

Indoor plants are usually fertilized with a mixture composed of N,P and K. Trace elements are applied only according to necessity. Some fertilizers are applied as top dressing or mixed with the medium during preparation. Liquid solutions of fertilizers are the most convenient to use. The usual method is to prepare the solution in a watering can and apply sufficient volumes to the moist medium. Correct fertilizing of container plants consists of keeping them alive and well, but not allowing them to grow too rapidly.

Grooming Indoor plants are displayed on areas where people are likely to spend a lot of their time. Hence such areas should look their best. Remove old leaves and spent flowers regularly Trim disproportionately long branches. Wipe the foliage periodically with a damp sponge if the plant looks dull and dusty Turn back plants regularly to keep them symmetrical and sturdy A layer of decorative mulch in the pot also will enhance the appearance of indoor plants.

Support and training Non climbing plants with long, slender stems need support. The simplest method of supporting such plants is to tie them to a thin stake or a split bamboo piece inserted in the centre of the pot. For better support use up to three stakes spaced equally around the edge of the pot. Pass the twine around them. Do not tie the stems tightly.

The climbing growth (eg. ivies) can be spiraled around different stakes. Some plants like hederas, climbing philodendrons and syngoniums produce aerial roots that grip

supportive objects like tree trunk. Plants like setcreaseas, tradescantias and zebrinas that are trailers but not climbers, look attractive when trained on supports such as small trellis or wire hoops.

Weed Management

weeds is not recommended, as many chemicals are phytotoxic to anthurium plants. Sometimes under too low light intensity, algae can grow on the leaf laminae and hamper plant photosynthesis. Increasing light intensity will cause the algae to die.

Pest Management

The most serious pest of anthuriums is the anthurium thrips, Chaetanaphothrips orchidii (Moulton). In severe infestations, anthurium thrips can damage every flower produced in infested shade houses. Anthurium thrips invade the unopened bud soon after the bud emerges from the stipules. The mature flower is deformed with white streaks and or scarring on upper and or lower surfaces of the flower.

Anthurium thrips can be effectively controled with contact/systemic insecticide sprays. An effective insecticide requires a minimum 4 – 5 insecticede spray applications at 2 week intervals or 7 – 8 weeks after initial spray applications. This 7 – 8 week period is needed because flower buds already injured at time of initial spray application are harvested 6 -8 weeks later as injured flowers. Effective insecticides protect newly developing anthurium buds from thrips injury during the 7 8 week period of spray application.

Disease Management

The two major diseases are bacterial blight and anthracnose. Blackening of the stem and decay of leaf axils are the symptoms of bacterial blight. Tiny circular black spots appear on leaf and spadix in case of anthracnose. Spraying mancozeb 0.3% or carbendazim 0.1% can control the disease. Root rot caused by Pythium and Phytophthora can be controlled by the application of potassium phosphonate 0.3%.

Plant Protection

Some of the serious diseases are bacterial blight, leaf spot, anthracnose, root rot and damping off. Yellowing of the plants is the main symptom of blight. The disease is favored by warm and wet weather. To control the disease, cut and remove the diseased portion and spray streptocycline 200 mg/l. Anthracnose is a fungal disease in which the flowers rot. Mancozeb 0.2% spray can control the disease. This can control leaf spot disease also. Root rot is another major problem in anthurium. Improper aeration leads to this disease. Pests like scales, mealy bugs, thrips and mites are also common. Appropriate plant protection measures should be taken against them.

Harvesting

The flowers are harvested after the spathe is completely unfolded. About 8-12 flowers plant are obtained annually. They are cut with long stalks when about two-thirds of the flowers in the spadix are open. If the flowers are to be transported to long distances, a water soaked cotton may be kept at the cut end of the stalk.

Processing

Pruning experiments have shown that anthurium plants develop well with three leaves. Growers do most of their pruning during the summer months when there is ample time for this chore, but the process is very time-consuming.

AverageYield & Area Under Cultivation

The pink-flowered miniatures (UH1003, UH1069, UH1070) give yields in excess of 8 flowers per plant per year.