Capsicum spp

CROP HISTORY AND DEVELOPMENT

The pepper originated in Mexico and the neighboring areas of Central America. Soon after Columbus' discovery of this plant, it was spread and grown worldwide as a spice and medicine. India referred to hot peppers as "Chillies" while Sprain called hot peppers "chili" a term still used today. The sweet pepper was popular in Spain and was referred to as "pimientos" to describe the red coloration and sweet taste. Today, pepper plants can be found growing wild in tropical areas around the world. Many countries grow it as a crop, China leading the world in production and the US right behind. In fact Georgia has 6,000-7,000 acres in pepper cultivation. Many of the hot peppers can be found in Latin America and China, but the US prefers sweet bell peppers. Peppers are used for fresh consumption, and they are processed into powders, sauces, and salsas. Many of the new cultivars grown today can be traced back to the early plants.

Consumption and Nutritional Value Bell peppers are eaten raw, cooked, immature and mature. Often nutritional content is altered by the changes in the way they are consumed. Per capita consumption of bell peppers in 1995 was 6.2 pounds. They are an excellent source of Vitamin C, Vitamin A, and Calcium. Red peppers have more of these qualities than the immature green peppers.

PLANT CHARACTERISTICS

Peppers grown in temperate regions are herbaceous annuals, but are herbaceous perennials where temperatures do not drop below freezing. Pepper plants growth habit may be prostrate, compact, or erect, but it is determinate in that after it produces nine to eleven leaves a single stem terminates in flower. These plants are grown for the edible fleshy fruit produced by this dichotomous growth. Peppers are non climacteric which means they do not produce ethylene. They need to stay on the vine to continue the ripening process. Root system. A deep taproot will form if the plant root system is uninjured during transplanting. The spindle root will develop fibrous secondary root systems spreading laterally and downward 36-48 in. On the soil surface the stem will produce adventitious roots, but not as easily as tomatoes.

Leaves: The leaves of the pepper plant arise singly and are simple, entire, and asymmetrical. Typical of all Solanaceae plants the leaves are arranged alternately on the stem. They are shiny and glabrous and vary in shape from broadly ovate to ovate lanceolate.

Flowers: The flowers develop singly or in twos or threes continuously as the upper structure of the plant proliferates. The corolla is white and five lobed, the anthers are bluish in color. The plant flowers have an open anther formation and will indefinitely self pollinate. They are also pollinated by insects, which will increase the chances of cross-pollination. Unlike tomatoes, whose pollen becomes nonviable in high temperatures, the pepper flowers pollen is not extremely heat sensitive and it remains viable up to 100° producing fruit throughout the season. Fruit. The fruit of a pepper plant is classified as a berry with colors ranging from green, yellow, red, purple, black, brown, white and orange. Green is an immature fruit, yet commonly eaten this way, and as the fruit matures it changes color. Color changes in most commercial cultivars are green to red, green to yellow or green to orange. Usually, fruits of the purple and white varieties have these colors as they develop, and therefore do not have a green stage. The fruit matures in four stages, from dark green to light green, and chocolate stage, which is when the red pigments develop in the fruit turning it brown. Finally, the fruit turns red and begins to soften. For fruit to set, the ovaries need to be fertilized. Auxin is then produced by the seeds, which determine fruit cell elongation. The number of seeds fertilized will determine the size and shape of the fruit.

Seed: The seed develop on the interior and attach to the veins. Fully developed seed is kidney shaped. There are about 4,500 seeds per ounce. When transplanting, about 6 ounces of seed are needed per acre, and if directly seeding about 2-3 pounds will be needed. Pepper seed need to be planted ¼ to ½ inch deep. It takes approximately 10 days for the seed to germinate. Temperature requirements for proper germination are higher for hot peppers, especially habaneros. The minimum Federal germination standard of seed is 55%. The optimum temperature for seed germination is 85°. The closer the temperature is to being optimum, the faster the seed will emerge.

PROPAGATION METHODS

Peppers may be direct seeded or grown from transplants. Direct seeding is beneficial only when the soil is 75-86°F. If the soil is cool they will germinate slowly if at all. With direct seeding, if plants are too close together they will produce only small fruit. They do not compensate for dense planting with a greater yield. Where there are no warm soils it is best to start seeds in a greenhouse and transplant to the field. It is best to start the plants 6-8 weeks in advance of transplanting. The transplants cannot be used until all danger of frost is over. The transplants must have a good established root system and have no flowers or fruits developing on the plant. To avoid environmental stress in the field, peppers should be hardened off, but not too much because plant growth can be substantially delayed by over hardening. To harden off the plants, first lower the temperature surrounding the plants 10-15° lower (7-10 days before putting plants out). Then reduce water frequency and fertilization.

CULTURAL PRACTICES

Peppers require well structured, friable, sandy loam. They require warm temperatures, weed control, irrigation and insect and disease management for maximum fruit production.

Soil Type: Soil preparation for peppers is generally the same as tomatoes, although peppers take up less amounts of nitrogen, phosphorus, and potassium. Well drained, friable soil with a pH between 6.5 to 7.5 is optimum for production. Soils below 6.0 should be limed to raise the pH before planting. Added organic matter will increase water holding capacity and supply nutrients and minerals for physical characteristics of the plant. The salt content should be low in the soil. Fertilizer Requirements. Even though peppers have shallow root systems they require high fertility in the early stages of growth and side dressings later on. Nitrogen fertilizer is banded below and to the side of the seed or plant, along with P banding during planting. As the plant grows, future banding should be done further away from the plant stem. Most peppers do not have a problem with minor element deficiencies. The % of macronutrients for sufficient growing are as follows: N 4.0-6.0, P 0.35-1.0, K 4.0-6.0, Ca 1.0-2.5, Mg .3-1.0 and there is no data on S. The micronutrients are measured and required in smaller amounts, referred to as parts per million (ppm). Peppers require Fe 60-300, Mn 50-250, B 25-75, Cu 6-25, Zn 20-200, and Mo has no data found. When the pepper plant is in full bloom but has not yet developed any fruit, it has been found that sufficient ranges of NPK were 4.0, 0.25, and 2.5 respectively. Yet as little as 3.0, 0.15, and 1.5 were deficient amounts of NPK during this same growth period.

Weed Control: Cultivation of weed species is one way to rid the field of unwanted plants, however herbicides are used where applicable. Many fresh market growers have found black plastic to be excellent for weed control.

Irrigation: Some form of water is necessary over the life span of a pepper plant. Whether it be rain or supplemental watering, it must be provided at a steady rate. Erratic watering causes physiological disorders in the fruit of the plant. There are three times during the pepper plants life that it is important to irrigate. The plant must be irrigated during root establishment. Other important times to irrigate during the pepper plant life is during flowering and fruit set. If the plants are under stress during this time, it is probable that they will abort the flowers. Steady irrigation practices while the fruit is growing and maturing will enhance the fruit quality. Drip irrigation has been found to be most effective for crops.

INSECTS

From seedling on, peppers have the risk of being attacked by insect pests. There are 35 insects that the pepper is susceptible to. The major ones include the Pepper Weevil, which is black colored, gray or yellow marked, Pepper Maggot, Cutworms, Flea beetle, Leaf Miner and Tomato Hornworms. By early summer aphids have multiplied to many numbers. The pepper maggots, earworms and borers become a problem. By late summer, if proper controls have not been taken the corn borers, armyworms, and corn earworms will reach devastating numbers.

DISEASES

For pepper growers the important diseases in pepper are bacterial leaf spot, Southern blight, Anthracnose, ripe rot, blossom end rot, bacterial soft rot, downy mildew, Fusarium wilt, and mosaic. Fungal Downy Mildew is a common problem with peppers. This fungal pathogen is caused by Peronospora tabacini. The symptoms are pale yellow areas on the upper sides of the leaves. On the lower side of the leaf the downy mildew appears in cool moist weather. It can easily kill seedlings. Ripe rot occurs on ripening fruits and is caused by Colletotrichum nigrum. Small yellow spots appear and may not advance if weather is dry. After harvest if the fruit is kept in a warm humid atmosphere the spots rapidly enlarge within a single day and fruit are unfit for use. It then infects the seed cavity and destroys it. Other fungal pathogens include Fusarium wilt (Fusarium annuum), Verticillium wilt (Verticillium spp.), Phytophthora blight (Phytophthora capsici), and Southern blight (Sclerotium rolfsii).

Bacterial Two bacterial pathogens are important to mention: the Bacterial soft rot (Erwinia carotovora) which causes a soft slimy rot, and the bacterial spot (Xanthomonas versicatoria) which forms a raised rough pimply area on the fruit. On the leaves, the spot is first raised and wart like, and becomes necrotic spots with dark margins. The affected leaves turn yellow and drop. Most cultivars currently used for commercial production show resistance to BLS races 1, 2, and 3.

Viral The main viral infection that infects pepper is the Tobacco Mosaic Virus (TMV). The leaf becomes distorted and mottled while stunting and fruit malformation occurs.

Abiotic Disorders The most common problems with peppers are the abiotic physiological disorders. Blossom End rot occurs from calcium deficiency, and sporadic water and moisture fluctuations. The blossom end dries, turns brown to black and feels leathery. It can spread over half of the fruit. Sun scald is another physiological disorder that occurs commonly on sweet peppers when the fruit is exposed to hot sun. The flesh becomes light, dry and papery on areas that had direct sunlight on them.

HARVESTING

Florida, Texas and California have the highest production of peppers. Bell peppers must be hand harvested for fresh market due to the sensitivity of the fruit to bruising and the brittle nature of the plant. Depending on what stage you pick the fruit, between 60-90 days are required from transplanting to harvest. In 1993-1995 the yield of bell peppers was 223 cwt/acre in the United States. The peppers are ready for harvest when they are shiny, firm, and when they will turn back to their original shape after being lightly squeezed. Many irregular shapes occur in the pepper fruit, yet this does not make the quality any less valuable. Pepper plants produce fruit in cycles, new fruit will set after the first flush is harvested.

POST HARVEST

As soon as peppers are harvested they should be hydrocooled to remove field heat quickly. There are some risks in this procedure if the fruits are not dried immediately after soaking. Most pepper growers put the peppers through a 10% chlorine wash to remove fungus. Without a chlorine wash, a 50% increase in disease may occur. Peppers are definitely susceptible to chilling injury and should not be held at temperatures below 45 °F. If stored below this temperature then sheet pitting, alternaria rot on fruit and calyx, and darkening of the seed may occur. The symptoms usually do not occur until after the fruit is taken into warmer temperatures and results in sunken lesions on the fruit. Their storage life at 45-55°F and 90-95% relative humidity is 2-3 weeks. Due to the higher respiratory and metabolic rates of immature fruits, a shorter shelf life can be expected. Red peppers also have a shorter shelf life because degradation has already begun and the cell walls continue to become softer. Like many other fruits and vegetables, ethylene will quickly turn peppers from green to fully ripe colors. Hence, peppers should not be stored with ethylene releasing commodities. Waxing peppers before shipping is a very common practice to reduce moisture loss and resist bruising while in transit.

MARKETING

Bell peppers are eaten raw, cooked, immature and mature. Often the nutritional content is altered by the changes in the way they are consumed. Per capita consumption of bell peppers in 1995 was 6.2 pounds. They are an excellent source of Vitamin C, Vitamin A, and calcium. Red peppers have more of these qualities than the immature green peppers.