Fibres

Cotton

Land Requirements

Land to be used for production of cotton seed must be free of volunteer plants of cotton. The soil should be deep, well drained, retentive of moisture and fertile. There should be no hard pan in the sub-surface layer and also it should be free from the hard layer of carbonates that interferes in the proper development of plants, and therefore the seed.

Isolation Requirements

Cotton is mainly a self-pollinated crop, but natural corss-pollination to the extent of 10 to 50 per cent in g.hirsutum, 1 to 2 per cent in g.arboreum and 5 to 10 per cent in G.barbadense has been recorded in various countries. The actual isolation requirement varies according to the extent of natural cross-pollination. For cotton seed production, only one vareity at a farm is a highly desired practice. In India, a minimum isolation distance of fifty metres for foundation seed class and thirty metres for certified seed class production, from fields of other varieties, of the same species, fields of the same variety not conforming to varietal purity requirements for certification, and five metres from varieties of different spp.(different poidy levels) is required.

Time of Sowing

For best results, the cotton should be sown about one week or more earlier than the usual date of the onset of monsoons.

Preparation of Land

The land should be ploughed deep and harrowed two to three times, followed by levelling to make it well pulverised and levelled.

Source of Seed

Obtain breeder's/foundation seeds from source approved by a seed certification agency. The seed is usually treated with the appropriate recommended chemicals. If not, it should be treated with mercurials.

Method of Sowing

The usual seed rate is 15-25 kg/ha for American cotton and 12-16 kg/ha for desi cotton varieties. Spacing of 75-90 cm between rows and 30-45 cm between the plants is recommended. Apply basal dose of fertilisers along with 25 kg disulphoton, 5 per cent per hectare, or 20 kg phorate, 10 per cent per hectare, to the plot uniformly, at the base of each ridge. the sowing should be done by dibbling two to three seeds per hill. Irrigate immediately after sowing and give second irrigation four days after seeding. In case the germination is unsatisfactory gap tilling may be done by seedlings simulataneously raised in polythene bags. Gap tilling at a later stage is best avoided. the thinning may be done after 20 to 23 days to regulate one seedling per hill.

Fertilisation

The seed crop should be raised by liberal application of the various nutrients. the nutrient supply should be made according to the yield potential ofvarieties in different agroclimatic regions. In general, apply 15-25 cart loads of farm yard manure per hectare before opening of ridges. apply 50 kg nitrogen 50 kg phosphorus and 50 kg potash per hectare as a basal dose. Top-dress twice at the rate of 25 kg nitrogen per hectare once after sixty days and again at ninety days from planting. The crop at no stage should be allowed to suffer due to nutrient deficiency. Foliar sprays at the rate of 20 grams of urea or 15 grams of DAP per litre of spray fluid may be given with advantage during the boll development period, at an interval of ten days.

Irrigation

Depending on soil type and climate conditions, irrigate the crop once in 15 to 20 days. Heavy irrigation during flowering period should be avoided. Give light irrigation after each picking. The system of furrow irrigation should be adopted.

Interculture and weed control

Intercultivate the field four to five times during the crop period so as to keep the plot clean. Hand weeding may be done when required. Herbicides such as, TOKE-25, MSMA and cotoran can also be used for weed control..

Insect and Disease Control

Adopt recommended IPM methods

Roguing

Roguing of seed crop for off-types and diseased plants, should begin at seedling stage. the subsequent roguing for off-types and severely diseased plants should be done at square initiation stage and flowering stage.

Picking

The time of picking is an important aspect for maintaining seed quality. the picking should commence when the cotton is fully mature, i.e., when the bolls begin to open. Several pickings may be necesssary since bolls ripen over two to three months. the early pickings give a slightly better germination, but planting seed isbest gathered at the peak of the harvest. The cotton picked from late-formed bolls (last pickings) should not be kept for seeds.
Precautions to be taken in picking:

  • Start picking when bolls are fully mature.
  • Picking should not be done while the bolls are wet from dew or rain.
  • Bolls spoiled due to rains, or damaged by insects, orotherwise damaged, should be picked separately and discarded for seed purposes. Such bolls can be picked 10 to 15 days ahead of the first picking. The damaged bolls should not be picked during normal pickings for seed purposes.
  • The cotton should be clean, with a minimum amount of such material as leaves and plant barks. This reduces the possibility of mechanical damage from excessive machining of the fibre during ginning.
  • Cotton moist in any way should not be picked or stored. At a moisture content of twelve per cent, or more,heating may occur and damage the seed and fibre. Further, damp cottonrequires more processing in the gin and exposes the seed to mechanical damage.
  • the picked cotton, when it is completely dry,should be stored in a dry place and should be covered if not ginned immediately.

Ginning

Ginning has a big role in cotton seed quality. Ginning of cotton seed shouldbe done on one variety gins, or gins approved by the certification agency. the ginning machinery must be thoroughly cleaned before ginning the seed crop. In ginning, the cotton should be subjected to a minimum amount of machining to minimise the mechanical damage.

Seed Yield

The average seed yield varies from 3 to 6 qtl per hectare.

Jute

Land Requirements

Land to be used for seed production shall be free of volunteer plants. In addition, the land should be fertile, well-drained and neither very acidic not very alkaline. It should be free from obnoxious weeds and soil-borne diseases such as stem rot.

Isolation Requirements

Jute is normally a self-pollinated crop but some corss-pollination does occur. Natural crossing has been recorded at two to three per cent in C.capsularis, and ten totwelve per cent in C.olitorius. For certified seed production, seed fields should be isolated by a minimum distance of fifty metres in the case of the foundation seed class, from fields of other varieties ofthe same species, and fields of the same vareity not conforming to varietal purity requirements for certification. From fields of other species a minimum isolation distance of five metres should be provided.

Time of Sowing

The best sowing time is May to mid June.

Preparation of Land

The land should be well-prepared by deep ploughing, and five to six cross harrowings followed by levelling. Fine tilth is necessary to ensure good germination.

Source of Seed

Obtain breeder's/foundation seeds from source approved by a seed certification agency.

Seed Rate

Capsularis varieties - 8 to 10 kg per hectare
Olitorius varieties - 4 to 6 kg per hectare.

Method of Sowing

Sowing in lines should be prefered to the broadcasting method. It facilitates interculture, roguing and inspection of seed crop. The seed should not be sown more than 3 to 5 cm deep.

Fertilisation

The nitrogen requkrement of Capsularis varieties is 80to 100 kg/ha and that of Olitorius 60 to 80 kg/ha. Higher doses of nitrogen results in lodging. The applicationof nitrogen apply 20 to 30 kg phosphorus and potash/ha.Onacidic soils,.or in soils where there is incidence of root rot or stem rot application of lime and potassium sulphate at the rate of 700 to 1500 kg/ha reduce these diseases. All the phosphorus and potash and half of the nitrogen should be applied before sowing. Half of the remaining nitrogen should be applied after three to four weeks and the remaining after six weeks. Adequate moisture in the soil is necessary at the time of application of nitrogenous fertilisers.

Spacing

Row to row 30cm
Plant to plant 15-20

Irrigation

Irrigate as and when necessary. Usually two to three irrigations are required before the onset of the monsoons at an interval of twenty days

Interculture

The first hand weeding, mulching and thinning should be done whenthe crop is three to four weeks old. Subsequently, oneto two weedings by hand, or cultivator can be done as per requierement. Clipping should be done at 40-45 days of crop age for inducing growth of new axillary branches.

Insect and Disease Control

  • Treatment of seed with orgonomercurial compounds or captan.
  • Application of lime, potash in soil.
  • Timely weeding and thinning.
  • Crop rotation.
  • Uprooting and destroying infested plants.

Roguing

Roguing for off-types, diseased and pest infested plants should be carried out at three stages of the growth of the plant. The first roguing should be carried out when plants are 30 to 40 days old. Second roguing should be done in the bud or flowering stage and the third at capsule formation stage.

Harvesting and Threshing

Harvested for seed much in the same way that it is picked for the market. The fruit should not be left on the vine until decay begins.

Juice and Seed Extration: The canery equipment as pulpers and cyclones are primarily used, and after extraction the processers have in general two products: the juice and the pumice, or more or less the dry mass of squeezed pulp. skin and seeds. The only heat used may be scalding process to loosen the skin of the fruit. Such a mechanical method of seed extraction is rapid and leaves the seed practically free of seed extraction is rapid and leaves the seed practically free of the gelatinous tissue surrounding it in the fruit. Seed obtained by juice extracting equipment may be separated from the pumice by washing it with an abundant supply of water as described further on.

Ordinary seed extraction: When mechinery similar to that for vine crops is used, the chief difference is the lack of any heavy knives. The tomato is easily cut and crushed. It is usually made to pass between corrugated rollers before falling into a revolving wire mesh cylinder. the material and juice which passes through the screens is then poured into large tubes orvats where the extraction process is completed by one of the methods described below.

Separation by fermentation: The fermentation process is an old established procedure which effectively controls bacterial canker. It is best to allow the mass of fruit pulp and juice to ferment without theaddition ofwater. Fermentation should take place long enough forthe mucilaginous material adhering to the seed to distintegrate sufficiently so as to release the seeds, which sink tothe bottom. the undecomposed pulp floats to the top leaving a layer of clear liquid in between. Since, gas and floating pulp often entrap good seed and hold it in the upper layer, the contents of vats require fairly frequent stirring. Stirring tends to release such seed and also prevents fungus growth from starting at the survace of the mass.If thisfungus is allowed to grow, some discoloration and even injury to the seed may result.

Temperature determines to a large extent the length of time the fermentation process continues. If it reamins around 24 to 27 C most of the time, fermentation is rapid, and satisfactory separation of seed and pulp is attained in about two days. For thecontrol of canker, however, fermentationmust continue for at least 96 hours. Since such a long period may result in injury to the seed, it is advised that under such circumstances the fermenting pulp be kept as close to 21 C as possible. The lower thetemperature, the slower the fermentation process.

Acid separation: In the acid method, hydrochloric acid is added to the pulp at the rate 100ml forevery 14 kilogrammes of pulp (approximately 10 litres per tonne). If a thorough mixing of the acid and pulp occurs, the seeds may be washed free within 15 to 30 minutes. By proper arrangement ofequipment it is possible to have an almost continuous process.

The acid method has several advantages:

  • The seed can be extracted and dried on the same day.
  • Less number of vats are required.
  • The problems of low and high temperatures are avoided.
  • Discoloured seed resulting from fermentation is entirely eliminated.

To control bacterial canker theextracted seed, in addition, maybe treated with 0.8 per cent solution of pure acetic acid in water for24 hours, at temperature below 21 C.

Alkali separation: In alkali method equal volume of an alkali mixture (425 gm ordinary wahsing soda added to 5 litre of boiling water) is added to pulp and mixed. When the alkali mixture is cooled, allow it all tostand overnight in an earthen pot. Next day, all the seeds will settle down at the bottom ofthe container. Now decnt-off the clear liquid at the top and wash theseeds thoroughly.

Washing: After extraction the seeds are washed with water to remove the pulp, etc. The water is added to containers with the pulp and seed. It is stirred thoroughly and is drained out along with pulp and other mucilaginous substance. This process is repeated until the seeds are clean.

Drying: After washing, theseeds should be dried as rapidly as possible. Seed may be spread on screen bottom trays, or cloth, and placed in the open where a maximum exposure to sun and dry air is attained. The seeds should be dried to eight per cent moisture before storage.

Seed Yield

The average seed yield is about 100 to 120 kg per hectare.

Mesta

Land Requirements

Land to be used for seed production shall be free of volunteer plants. In addition, the land should be well-drained loam, rich in humus content. On poorly drained soils plants usually die before flower or seed is produced.

Isolation Requirements

Mesta is mainly a self-pollinated crop, though cross-pollination to varying degrees depending upon insect activity has been observed. For seed production the seed field must be isolated.

Time of Sowing

Mid -May to June

Preparation of Land

The land should be ploughed and harrowed four to five times, followed by levelling to provide a fine tilth.

Source of Seed

Obtain breeder's/foundation seeds from source approved by a seed certification agency.

Seed Rate

10-12.5 kg per hectare.

Method of Sowing

The seed crop should be sown in rows.

Fertilisation

Excessive nitrogen produces too much vegetative growth. The seed crop needs 70 to 80 kg nitrogen, 120 to 140 kg phosphorus and 90 kg potash per hectare. Higher doses of fertiliser are required for sandy soils where leaching is quite high. Foliar sprays of urea have also been found useful.

Spacing

Row to row - 30 cm
Plant to plant - 12 to 15 cm

Irrigation

One to two irrigations are necessary before the onset of the nonsoons. Subsequently, irrigate as and when required.

Interculture

The seed plot should be weed free. One to two hand weedings are necessry. First weeding and thinning may be done after three to four weeds. Subsequent weedings should be done as per requirements of the crop. The field must be cleaned of Convolvulus plants before the harvest so as to avoid mixture of Convolvulus seed with that of mesta seeds.

Insect and Disease Control

Adopt recommended IPM methods

Roguing

Roguing for off-types, plants affected with stem and root rot (Macrophomena phaseoli) should be done from time to time.

Harvesting and Threshing

The crop is ready for harvest when seeds on the lower and middle branches are ripe. The crop is cut by hand and left in the field todry for three to four days, this allows seed on the top branches to mature. Delayed harvesting results in shattering. Threshing of plants is done by hand, either by placing stooks on tarpaulins and flailing with long poles, or planks wrapped in canvas, or passing them through a stationery thresher. Later, seeds are winnowed with a coarse sieve and tanning mill. After winnowing , the seed should be dried to eight percent moisture before storage.

Seed Yield

The average seed yield is about 800 to 900 kg per hectare.