Harvesting of cotton Harvesting (picking) of cotton Kapas is perhaps the most costly and least efficient operation in cotton cultivation. Cotton usually harvested in three or more pickings Number of pickings depends on maturation habit of the variety, seasonal and cultivation conditions. In A.P Mungari (June sown) cotton pickings taken up between October to December. Picking of cotton is a slow and tedious operation. It is more so in case of Asiatic cotton since the boll size is small and number of plants / unit area are more. Middle pickings are usually heaviest and most important (except in herbaceums in which the first picking is the principal picking) Careless picking, collection and heaping of Kapas makes the cotton dirty – fetch minimum premium Skip – row planting facilitates easier pickings since the plants grow tall and compact with more concentration of bolls. Start picking when bolls are fully mature Picking should not done while the bolls are wet from dew or rain. Bolls spoiled during rain or damaged by insects or otherwise damaged should be picked separately and discarded for seed purpose. Seed cotton should be clean, with a minimum amount of such material such as leaves and bracts. Moist cotton in any way should not picked or stored. At a moisture content of twelve percent or more heat may generate and damage the seed and to fibre. Picked cotton, when completely dry, should be stored in a dry place and covered if not ginned immediately.

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Ginning Ginning is the first processing operation conducted by ginning Mills. Seperation of lint from seed Cotton is called ginning and this is expressed as ginning percentage. (out turn of lint to seed cotton expressed in percentage). Ginning percentage varies with species and within species due to varieties. In general it varies from 22 to 44. This is another important area which has been largely neglected so far. There are about 3600 ginning factories (saw and roller gins) and the total capacity exceeds the present requirements. In many factories, the machinery are very old, they are run without proper adjustments and maintenance and there are no facilities for pre-cleaning the kapas. In the absence of proper storage facilities, seed cotton is heaped in open space/under trees; similar is the case with pressed bales. While this is the situation in most of the factories, there are a very few ones established recently which have all modern facilities and produce clean. The ginning and pressing sector is now under the Ministry of Textiles and they have formed a committee under the Textile Commissioner with members from CCI, MSCGMF, EICA, ICMF, AICOTTON and CIRCOT to consider the problems and suggest plant for improving this sector. Hope fully, this sector would see the improvements it needs badly in a few years’ time. Area No. of Ginning & Pressing No. of bales pressed during 1998-99 season Costal Andhra 38 11,13,984 Rayalseema 16 3,57,731 Telangana 40 10,15,793 Loose consumption by local mills   15,000 Total Andhra Pradesh   25,02,508

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Spinning It refers to making yarn from lint. Spinning quality varies with species and also among species within cultivars. Spinning value is expressed as counts. – Spinning value is No. of hanks present in 1 pound of cotton.(1 hank = 840 yards) several factors influence spinning value viz., species, variety, cultivation practices, besides weather conditions. Quality characters that influence spinning count are fibre length, strength, fineness and trash content etc., Cotton made available to the textile industry should be well ginned with running lots free from contamination sticky-ness and have very low content of trash, seed coat bits and short fibres. Cotton processing and spinning technology has made very rapid strides in the past 10 – 15 years. As stated earlier, the trend has been towards achieving higher production and productivity coupled with automation so as to bring down the cost of production of yarn. Coming to the actual spinning process, the 3 new systems, called open-end (OE) spinning, that are rapidly replacing the conventional ring spinning system are: (I) Rotor spinning, (II) Friction (or DREF) spinning and (III) Air-jet spinning. The order of importance of various fibre quality parameters for different yarn production systems are given below: Ring Spinning Fibre Length (L) and length uniformity ratio (UR), fibre bundle tenacity (S) and fibre finess (expressed as Micronaire value Mv), are the important characteristics in that order which influence spinning performance on the ring spinning system. This system is suitable for spinning yarns of 6s to 120s count. The yarns produced have higher strength but lower uniformity than yarns produced by the other systems. The actual value of L.S and Mv decide the count to which the sample of cotton can be soun. Rotor Open-End Spinning S and Mv play a greater role during processing on rotor spinning, more commonly referred to as "open-end Spinning". This system is economically viable mainly for coarse and lower medium counts, although sometimes 30s count is also spun. The yarns produced are about 15% to 25% lower in strength than ring spun yarns, but with better uniformity and lesser hairiness. The optimum fibre quality requirements are S (at 3.2 mm guage) of 28-30 g/tex, Mv of 3.0 to 3.6 L (2.5 per cent span length) of 26-28mm. Trash content is critical; the cotton should be clean with less than 2% trash and very low micro dust content. Friction (DREF) spinning The order of importance of fibre characteristics is Mv, S, L, UR, and fibre friction. Cotton cleanliness is also very important. This system is also suitable for counts below 30s and is more useful for wool and man-made fibres rather than for cotton. The yarn strength is about 30% to 40% lower than ring spun yarn but the yarn is more regular and extensible. Air – Jet Spinning The fibre parameters mv, L and S are important in that order; cotton cleanliness is also very important. L of 30 mm and above is preferred. This system is suitable for spinning finer counts above 50s, and is mostly used for man-made fibres and blends, and also combed cotton. Compared to ring yarns, the yarn strength is lower by 10% (for man-made fibres) to about 30% (for cotton). Superior quality yarns are required to achieve high weaving standards with minimum defects especially with modern high speed looms. High quality in mixing / blending process and knot-free spliced electronically cleared yarn are essential for shuttleless weaving technology. In addition, freedom from shrinkage, high abrasion or wear resistance, fast-ness of colour and shade consistency are expected in fabrics and garments.

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Storage Cotton seed is unloaded at the mills and also moved into storage place by manual labour and no mechanical devices are employed. The seed is stored in separate godowns, mostly in Jute bags piled up in rows or heaped in a few cases in a loose condition. The majority of the godowns in which the seed is stored are closed pucca built godowns, without much access to air (or) light, but in some mills, the godowns are well ventilated, mills stock the seed either in gunny bags or in loose heaps. The mills stock the seed for periods varying from one month to a maximum of 10 months, but the majority stocks the seed for three to six months. Drying of the seed is not done prior to storage, nor is any forced aeration practiced. Factors that affect the viability of cotton seed on storage revealed that the moisture content on the seed during storage and the temperature of storage plays an important role. Storage under conditions of both high moisture and extreme desiccation is harmful to the longevity of the seed. Optimum conditions of storage were observed to be in the range of 20 to 40 per cent relative humidity corresponding to a moisture content in the seed of five to seven percent. Difficulties in Storage Storage of kappas offers many problems such as large space required, difficulties in handling due to its bulky nature - large storage space is required both at the farmer's level as well as at the market. Due to the lack of sufficient space, the farmer will be forced to bring his produce to the market. The produce needs to be dried before packed. Improper drying due to lack of proper yard at hill village will generally result in to the discoloration of the fibres. Even at the market level, the conventional packing of kappas in bales gives rise to problems such as requirement of large space and possible fire hazards. The market is forced to store the bales in open yards, invariably resulting into the deterioration of the quality of fibres.

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