Pepper requires a warm and humid climate. Though an annual rainfall of 250 cm is ideal for the proper growth of the crop, it can also come up well in low rainfall areas, if the pattern and distribution of rainfall are conducive. About 70 mm of rainfall within a period of 20 days may be sufficient for triggering of flushing and flowering process in the plant, but once the process is set on, there should be continuous, though not heavy, rainfall until fruit development starts. Any dry spell, even for a few days, within this critical period will result in substantial reduction of yield. Very long spells of dry weather are unfavourable for the crop growth.

The plant tolerates a minimum temperature of 10 ºC and maximum of 40 ºC, the optimum being 20-30 ºC. It can be grown from sea level up to an altitude of 1200 m but lower altitude is preferable.
Pepper prefers a light porous and well-drained soil rich in organic matter. Water stagnation in the soil, even for a very short period, is injurious for the plant. So, heavy textured soils in locations where drainage facilities are inadequate should be avoided.

Varieties

Panniyur-1, Panniyur-2, Panniyur-3, Panniyur-4, Panniyur-5, Panniyur-6, Panniyur-7, Subhakara, Sreekara, Karimunda, Panchami, Pournami, Kottanadan, Kuthiravally, Arakulam Munda, Balankotta and Kalluvally are the commonly cultivated varieties. Of these, Panniyur-1 is to be grown in comparatively open areas.

Selection of site
Sites with slight to moderate slope are ideal for pepper cultivation, as they promote drainage. Slopes facing south are to be avoided as far as possible. When such slopes are to be used for cultivation, the young plants may be sufficiently protected from the scorching sun during summer.

Selection of mother plants
Cultivate only varieties, which are proven to be highly productive. Select mother plants, which give regularly high yields and possess other desirable attributes such as vigorous growth, maximum number of spikes per unit area, long spikes, close setting of berries, disease tolerance etc. Selected mother plants should be in the age group of 5-12 years. Mark and label selected mother plants in October-November.

Raising rooted cuttings
Pepper is propagated vegetatively from cuttings. Select runner shoots produced at the base of mother plants and keep them coiled and raised to prevent from striking roots in the soil. Separate them from the vines in February-March. The middle one-third portion of runner shoot is preferred for planting. Very tender and too hard portions of the shoots are to be avoided. The shoots are cut into pieces with 2-3 nodes in each. Leaves, if any, are to be clipped off leaving a small portion of the petioles on the stem. Dipping the lower cut end (up to 2 cm) of the cuttings in 1000 ppm solution of 3-indol butyric acid (IBA) for 45 seconds will increase root formation and development. The solution can be prepared by dissolving 1 g of IBA in one litre of water containing 3-5 g of sodium carbonate (washing soda). The dipping period of 45 seconds should be strictly adhered to, as any deviation from this may be injurious. Treating the cuttings with Seradix B2 is equally effective. But IBA treatment is cheaper and hence is recommended for large nurseries where technical supervision is available. Seradix B2 can be conveniently used by farmers and small-scale nurseries. Plant the treated cuttings in nursery beds or preferably in polythene bags or baskets filled with potting mixture. The potting mixture is prepared by mixing two parts of fertile topsoil, one part of river sand and one part of well rotten cattle manure. When polythene bags are used, sufficient number of holes (16-20) may be provided at the base to ensure good drainage. The cuttings should be planted at least one node deep in the soil. The cutting after planting should be kept under good shade. In large nurseries, pandals are to be constructed for this purpose. The cuttings are to be well protected from direct sunlight and frequent watering is recommended in the nursery to maintain a humid and cool atmosphere around the cuttings. Watering 2-3 times a day is sufficient. Heavy watering, which makes the soil slushy and causes waterlogging is to be avoided.

Planting
Planting of standards is to be taken up in April-May with the onset of pre-monsoon showers. Murukku (Erythrina indica) karayam or killingil (Garuga pinnata), Ailanthus sp., subabul (Leucaenea leucocephala) etc. are suitable standards for growing pepper. In high altitude areas, dadap (E. lithosperma) and silver oak (Grevillea robusta) can be successfully used as standards for pepper. Seedlings of subabul and silver oak are to be planted 2-3 years before planting pepper. The cuttings of standards are to be planted in narrow holes of 40 to 50 cm depth. The spacing recommended is 3 x 3 m on plain lands and 2 m between plants in rows across the slope and 4 m between rows on sloppy lands. The soil should be well pressed around the standards to avoid air pockets and keep the standards firm in the soil.

For planting pepper, prepare pits on the northern side of standards, 15 cm away from it. The pit size should be 50 x 50 x 50 cm. Fill the pits with a mixture of topsoil and compost or well rotten cattle manure @ 5 kg/pit. With the onset of southwest monsoon in June-July, plant 2-3 rooted cuttings in the pits at a distance of about 30 cm away from the standards. Press the soil around the cuttings to form a small mound slopping outward and away from the cuttings to prevent water stagnation around the plants. The growing portions of the cuttings are to be trailed and tied to the standards. Provide shade to the plants if the land is exposed and if there is a break in the rainfall. When pepper is grown on coconut or arecanut trees, the pepper cuttings are to be planted 1-1.5 m away from the trunk of the trees. Trail the pepper vines on a temporary stake for 1-2 years. When they attain sufficient length to reach the tree trunk, remove the stake without causing damage to the vines and tie the pepper plants on to the tree trunk and trail them on it.

Management after planting
If the terrain of the land is sloppy or uneven, carry out contour bunding or terracing to prevent soil erosion. Carry out digging around the standards and vines at a radius of about 1 m from the base or in the entire plantation, twice during the year, the first at the onset of southwest monsoon and the second towards the end of northeast monsoon. Weeding around the plants is to be done according to necessity. However, in foot rot affected gardens, digging should be avoided and weeds removed by slashing. In the early stages, tie the vines to the standards, if found necessary.

Where pepper is grown on a plantation scale, growing of cover crops like Calapagonium muconoides is recommended. When such cover crops are grown, they are to be cut back regularly from the base of the plants to prevent them from twining along with the pepper vines. Lowering of vines after one year's growth will promote lateral branch production.

Intercropping of pepper gardens with ginger, turmeric, colocasia and elephant foot yam is advantageous. Banana as an intercrop in yielding gardens reduces pepper yield. Therefore, this is not recommended beyond three to four years after planting of pepper vines. However, in the early years, banana provides shade to the young plants and protects them from drying up during summer months.

When pepper is grown in open places, shading and watering of the young seedlings may be done during summer months for the first 1 to 3 years according to necessity. The young plants may be completely covered with dry arecanut leaves, coconut leaves or twigs of trees until summer months are over. Mulching the basins of pepper vines during summer months is highly advantageous. Saw dust, arecanut husk and dry leaves are suitable mulching materials. Removal of unwanted terminal shoot growths and hanging shoots should be done as and when necessary.

Prune and train the standards in March-April every year to remove excessive overgrowth and to give them a proper shape. The effective height of the standard is to be limited to about 6 m. A second pruning of the standards may be done in July-August, if there is excessive shade in the garden.

Underplanting
After regular bearing for about 20 years, the vines of most varieties start declining in yield. The age of decline in yield varies with variety and agroclimatic and management factors. So underplanting should be attempted at about 20 years after planting or when a regular declining trend in yield appears. The old and senile vines can be removed 3-5 years after underplanting depending up on the growth of the young vines.

Manuring

Manuring for pepper vines is to be done in basins taken around the plant, 10-15 cm deep and 50-75 cm radius, depending up on the growth of the plants. Apply cattle manure / compost / green leaves at the rate of 10 kg / plant / annum just at the onset of southwest monsoon and cover lightly with soil. It is desirable to apply lime at the rate of 500 g/vine in April-May, with the receipt of pre-monsoon showers, in alternate years.

Recommended nutrient dosage for pepper (3 years and above) is:

N:P₂O₅:K₂O g/vine/year
50:50:150 (general recommendation)
50:50:200 (for Panniyur and similar areas)
140:55:275 (for Kozhikode and similar areas)

Note: Apply 1/3 dose for one-year-old plants and 1/2 dose for two-year-old plants.

The fertilizers may be applied in two split doses, the first in May-June with the receipt of a few soaking rains and the second in August-September. Apply fertilizers in a circle of radius 30 cm around the vine in the case of plants trailed on erythrina (murukku) or teak pole (dead standard).

Irrigation
Irrigating pepper plants of Panniyur-1 variety at IW/CPE ratio of 0.25 from November / December till the end of March and withholding irrigation thereafter till monsoon break, increases pepper yield by about 50%. The depth of irrigation recommended is 10 mm (100 litres of water per irrigation at an interval of about 8-10 days under Panniyur conditions). The water is to be applied in basins taken around the plants at a radius of 75 cm. The basins may be mulched with dry leaves or other suitable materials.

Bush pepper
By planting lateral branches (plagiotropes) of pepper, the vine can be grown as a bush. One-year-old lateral branches with 3-5 nodes are to be planted in nursery during March-April for pre-rooting after treating the cut ends with 1000 ppm solution of IBA for 45 seconds. Rooting percentage of laterals is less than 20%. Only well-rooted and established plants are to be used for transplanting. The rooted cuttings are to be planted at 3-5 per pit or per pot. Fertilizers can be applied @ 1.0, 0.5 and 2.0 g/pot of N, P₂O₅ and K₂O respectively at bimonthly interval. Alternatively, application of 15 g groundnut cake (or) 33 g of neem cake can also meet the N requirement of the crop. The bushy nature of the plant will have to be ensured by proper pruning of the hanging shoots. The potted plants are to be kept preferably under partial shade. It is necessary that re-potting is carried out after every two years.

Plant protection

Pests
For the control of pollu caused by the flea beetle Longitarsus nigripennis, spray any one of the following insecticides namely, endosulfan, dimethoate, quinalphos, or monocrotophos at 0.05% concentration. The spraying is to be given at the time of spike emergence (June-July), at berry formation (September-October) and once again at berry maturing stage, if needed. It can also be controlled by spraying cypermethrin 0.01% twice, first at the berry formation stage and the second one-month after the first spray
(Sept-Oct.).

For controlling pepper leaf gall thrips, monocrotophos (0.05%) or dimethoate (0.05%) may be used. For control of grubs (Remphan sp.) that damage roots of live standards and teak poles, apply phorate at the rate of 2 g ai / standard, into the soil around the base through slanting holes.

Soft scale (Lecanium sp.) is occasionally found to infest the foliage and vines at higher elevations. This scale insect can be controlled by spraying quinalphos 0.05%. This treatment will be adequate to control the mealy bugs also. Root mealy bugs can be controlled by drenching the basins of vines with chlorpyriphos 0.075%. Adequate precaution has to be taken to ensure that the insecticide solution reaches the root zone of the vines. Many of the vines infested by root mealy bugs are also likely to be infected with Phytophthora and nematodes. For controlling hard scale, spot application of dimethoate 0.1% is recommended.

Top shoot borer can be controlled by spraying monocrotophos (0.05%) or dimethoate (0.05%) on the tender shoots and flushes. The spraying has to be repeated to protect newly emerging shoots and flushes.

For control of the burrowing nematode Radopholus similis and the root knot nematode Meloidogyne incognita, adopt the following measures:
(a) Use nematode free rooted cuttings for raising new plantations.
(b) For the nematode infested vines, apply phorate / carbofuran @ 1 g ai/vine twice in a year. The first dose is to be given in May-June at the onset of monsoon and the second dose in the last week of October or early November. The chemicals are to be applied around the vines in shallow basins and incorporated into the soil.
(c) Root knot nematode can be effectively managed by the application of bacterial suspensions of Bacillus macerans or B. circulans prior to planting of vines or just before the monsoon period in established plants (Ad hoc recommendation)

Diseases
Phytophthora foot rot
For controlling the disease, adopt the following management practices:

Phytosanitation
All infected or dead vines along the root system are to be removed and burnt. Wherever water stagnation is a problem, effective drainage of both surface and sub-soil is to be ensured. To avoid soil splash and consequent disease initiation and spread, a legume cover in the plantation should be ensured. Runner shoots are to be pruned or tied back to vines before the onset of monsoon. At the onset of monsoon, the branches of support trees may be lopped off to allow penetration of sunlight and avoid build up of humidity.

Apply 1 kg lime and 2 kg neem cake per standard per year as pre-monsoon dose. The application of neem cake should be four weeks after lime application.

Chemical control

For the control of Phytophthora foot rot, any of the following control measures can be adopted.

1. After the receipt of monsoon showers (May-June), all the vines are to be drenched over a radius 45-50 cm with 0.2 % copper oxychloride at the rate of 5-10 litres per vine. This varies according to the age of the plant. A foliar spray with 1 % Bordeaux mixture is also to be given. Drenching and spraying are to be repeated just before the northeast monsoon. A third round of drenching may be given during October if the monsoon is prolonged.

2. After the receipt of a few monsoon showers (May-June), all the vines are to be drenched over a radius of 45-50 cm with 0.3% potassium phosphonate at the rate of 5-10 litres per vine. This varies according to the age of the plant. A foliar spray with 0.3% potassium phosphonate is also to be given. A second drenching and spraying with 0.3% potassium phosphonate is to be repeated just before the northeast monsoon. If the monsoon is prolonged, a third round of drenching may be given during October.

Bio-control

Inoculate pepper vines with native arbuscular mycorrhizal fungi, Trichoderma, and Pseudomonas fluorescens at the time of planting in the nursery and field, and apply during the pre-monsoon period in the established plantations to control foot rot. In the field, apply the biocontrol agents around the base of the vine (see the chapter on biocontrol agents against plant pathogens).

Note: (1) All chemical control measures are prophylactic in nature and application of chemicals in advanced stages of disease will not be effective in combating the disease. (2) In Phytophthora sick fields, use only chemical control measures.

Replanting / rejuvenation
Total replanting has to be undertaken in gardens where the mortality is 50-60% or above. Where the mortality is below 50%, timely plant protection measures as described above should be given to all the existing vines as prophylactic measure and gaps filled up. Gap filling or replanting should be taken up only after a period of one year. At the time of replanting, soil drenching with Bordeaux mixture or copper oxychloride should be given. While replanting, farmers should be encouraged to use recommended varieties.

Fungal pollu (Anthracnose)

For the control of fungal pollu or anthracnose caused by Colletotrichum gloeosporioides, spray 1% Bordeaux mixture, once before flowering starts (late June and early July) and then at berry formation stage (late August). Minimize shade in the garden.

Wherever Phytophthora foot rot management is undertaken properly, separate control measures for pollu disease may not be necessary.

Note: Since Bordeaux mixture application for pepper is to be given mostly at a time when the monsoon is very active, it is to be ensured that a sticker is added to the fungicide. The cheapest and most effective sticker is rosin washing soda mixture.

Rotting disease
For control of rotting disease of seedlings in the nursery, VAM and Trichoderma can be applied in the potting mixture. VAM inoculum consisting of root bits and soils can be applied at the rate of 100 cc per kg of potting mixture and Trichoderma @ 1g/kg of potting mixture. For the control of foliar infection apply potassium phosphonate @ 3 ml/litre at fortnightly interval. In case, biocontrol agents are not incorporated in the potting mixture, 1% Bordeaux mixture spray at weekly interval may be resorted to. When the cuttings start germination, ensure good aeration in the nursery. Heavy watering, which causes water stagnation is to be avoided. Instead, light and frequent watering should be resorted to. Remove shade as soon as continuous rain sets in.

Phyllody
In certain pockets, instead of normal spike with berries, leaf-like structures are produced. This is caused by phytoplasma. Such vines, if noticed, must be uprooted and destroyed. Planting material should not be collected from such vines.

Stunted disease
The symptoms due to this disease include shortening of internode and narrowing of leaves with mottling. Such leaves also become leathery and deformed. This is caused by a virus. Since the disease is systemic and transmitted through planting materials, extreme care should be taken to avoid collecting planting materials from such vines. Once it is noticed, it is better to uproot the vines even at the cost of losing some yield to avoid further spread.

Waiting period of insecticide / fungicide

Dimethoate                20 days
Quinalphos                20 days
Mancozeb                 30 days

Harvesting and processing

Black pepper
Black pepper of commerce is produced from whole, unripe but fully developed berries. The harvested berries are piled up in a heap to initiate browning. Then they are spread on the suitable drying floor after detaching the berries from the stalk by threshing. During sun-drying, berries are raked to ensure uniform colour and to avoid mould development. Drying the berries for 3-5 days reduces the moisture content to 10-12 per cent. The dried berries are garbled, graded and packed in double lined gunny bags.
Blanching the berries in boiling water for one minute prior to sun drying accelerates the browning process as well as the rate of drying. It also gives a uniform lustrous black colour to the finished product and prevents mouldiness of berries. But prolonged blanching should be avoided since it can deactivate the enzymes responsible for browning process.

White pepper
White pepper is prepared from ripe berries or by decorticating black pepper. Bright red berries, after harvest are detached from the stalk and packed in gunny bags. The bags are allowed to soak in slow running water for about one week during which bacterial rotting occurs and pericarp gets loosened. Then the berries are trampled under feet to remove any adhering pericarp, washed in water and then sun dried to reduce the moisture content to 10-12 per cent and to achieve a cream or white colour. White pepper is garbled, sorted and packed in gunny bags. Approximately 25 kg white pepper is obtained from 100 kg ripe berries.

Improved CFTRI method

Fully mature but unripe berries are harvested and boiled in water for 10-15 minutes to soften the pericarp. After cooling, the skin is rubbed off either mechanically or manually, washed and sun dried to obtain white pepper. Since no retting operation is involved, the product will be free from any unpleasant odour. However, white pepper produced by this method gives pepper powder of light brown colour due to gelatinisation of starch in contrast to pure white powder obtained by traditional method.

Decorticated black pepper
This is a form of white pepper produced by mechanical decortication of the outer skin of black pepper. This is generally done when white pepper is in short supply. The appearance of decorticated kernel is inferior to traditionally prepared white pepper, but is satisfactory when ground. Also the milling operation requires considerable skill to avoid excessive volatile oil loss.

Dehydrated green pepper
In this method, under-mature berries are harvested and subjected to heat treatment for inactivating the enzymes responsible for browning reaction. Then the berries are dehydrated under controlled conditions wherein maximum retention of green colour is obtained. Dehydrated green pepper after reconstitution in water resembles freshly harvested green pepper. The advantage is that the season of availability can be extended and the berries could be stored for a year or more. Dry recovery comes to 20 per cent.

Canned green pepper
Green pepper after harvest is preserved in two per cent brine solution and the product is heat sterilized. This product has the additional advantage over dehydrated green pepper in that it retains the natural colour, texture and flavour.

Bottled green pepper
Green pepper is preserved without spoilage in 20 per cent brine solution containing 100 ppm SO2 and 0.2 per cent citric acid. Addition of citric acid prevents blackening of berries.

Cured green pepper
To overcome the disadvantages of poor texture and weak flavour of dehydrated green pepper and the high unit weight and packing cost of canned and bottled green pepper, cured green pepper has been developed. Berries are thoroughly cleaned in water, steeped in saturated brine solution for 2-3 months, drained and packed in suitable flexible polyethylene pouches.

Freeze-dried green pepper
Most of the moisture from fresh tender green pepper is removed by freezing the berries at -30ºC to -40ºC under high vacuum. The colour, aroma and texture of freeze-dried green pepper are superior to sun dried or mechanically dehydrated green pepper. Freeze-dried green pepper has 2-4 per cent moisture and is very light.

Pepper oil
Black pepper is crushed to coarse powder and steam distilled to obtain 2.5 to 3.5 per cent colourless to pale green essential oil which becomes viscous on ageing. It is used in perfumery and in flavouring. Oil can also be distilled from white pepper but high price of white pepper and low oil yield do not favour its commercial production.

Pepper oleoresin
Extraction of black pepper with organic solvents like acetone, ethanol or dichloro-ethane provides 10-13 per cent oleoresin possessing the odour, flavour and pungent principles of the spice. The content of the pungent alkaloid piperine ranges from 4 to 6% in dry pepper and 35 to 50% in oleoresin. When freshly made, pepper oleoresin is a dark green, viscous, heavy liquid with a strong aroma. One kg of oleoresin when dispersed on an inert base can replace 15 to 20 kg of spice for flavouring purpose.

Table 23. Drying percentage and oil content of Panniyur varieties of pepper