Dr Omer Farooq & Dr Muqarrab Ali
Cotton an important cash crop and plays a vital role in the economy of Pakistan. Cotton is a soft fibre that grows around the seeds of the cotton plant (Gossypium sp.), a shrub native to tropical and subtropical regions around the world, including the Americas, India, and Africa.
However, virtually all of the commercial cotton grown today worldwide is grown from varieties of Native American species Gossypium hirsutum and Gossypium barbadense. The fibre is most often spun into yarn or thread and used to make a soft, breathable textile, which is the most widely used natural-fibre cloth in clothing today. The English name derives from the Arabic word al qutun, meaning "cotton fibre". (The Spanish word algodón has the same etymology.) Cotton fibre, once it has been processed to remove seeds and traces of wax, protein, etc., consists of nearly pure cellulose, a natural polymer.
Cotton production is very efficient, in the sense that ten percent or less of the weight is lost in subsequent processing to convert the raw cotton bolls (seed cases) into pure fibre. The cellulose is arranged in a way that gives cotton fibres a high degree of strength, durability and absorbency. Each fibre is made up of twenty to thirty layers of cellulose coiled in a neat series of natural springs. When the cotton boll is opened, the fibres dry into flat, twisted, ribbon-like shapes and become kinked together and interlocked. This interlocked form is ideal for spinning into a fine yarn. The seven largest producers of cotton in the world are ranked as China, India, USA, Pakistan, Brazil, Uzbekistan and Turkey. There are number of enemies of this crop in our cropping system so the only option to get maximum profitability from this “White Gold” is by adopting “Good Management Practices (BMP)” starting from crop sowing to the last picking.
Regardless of the tillage and crop production system, the optimum cotton crop would be free of stress from insects, mites, nematodes, seedling diseases, weeds, and other manageable factors, such as fertility levels and water availability. An optimum cotton crop at 40 days after planting would be a picture of health. In addition to being stress-free, the crop would exhibit healthy leaves, with roots extending into the row middles, and plants growing rapidly and uniformly.
The cotton crop has low nutrients requirements during early growth stages as it utilizes 20% of nitrogen requirements during first 60 days after sowing. The optimum plant would have seven to eight nodes and would be in the early stage of squaring. Crop uniformity has a significant impact on season-long crop management. A uniform crop allows for a more efficient crop management system, which ranges from application timing of herbicides and plant growth regulators to harvest aids.
An adequate plant population would be at least 21,000 plants per acre but not more than 25,000 while, in Pakistan generally average plant population in farmer’s field is less than 14,000 plants per acre. Achieving an optimum crop 40 days after planting contributes to an efficient season-long crop management system, including weed control, plant growth regulation, arthropod pest management, fertility, and harvest aid management. The ultimate goal of BMPs is a holistic and integrated, cost-effective crop management system that optimizes yield and fibre quality.
Cultivar selection and seed quality have a lasting effect on the crop’s early-season vigour and on overall plant health and uniformity during The First Forty Days. So it must be considered as a critical step while go for cotton cropping. It should be resistant type, disease free, treated with some fungicide and having high genetic potential.
It has been observed that the tolerant varieties, if attacked early in the season, have the ability to recover from CLCV effects. The farmers are advised not to plough such fields but to adopt recommended practices of cultivation to harvest reasonable yield of seed cotton. To avoid stress conditions, manage fertility and irrigation; Scout the crop/field properly and apply insecticides/herbicides on an as-needed basis, according to recommendations of Agriculture Extension Department’s threshold guidelines especially during periods of cool temperatures or extremely dry conditions.
The developmental phases for cotton can be divided into five main growth stages: (1) germination and emergence (2) seedling establishment (3) leaf area and canopy development (4) flowering and boll development and (5) maturation.
The transitions between these stages are not always sharp and clear. Each stage may also have different physiological processes operating within specific requirements. If producers are aware of these stage-dependent differences in cotton growth and requirements, then many problems in crop management can be avoided, which will result in higher yields and profits.
It has been observed that temperature is major key factor effecting all the major yield and quality parameters of the crop. So, farmers who efficiently manage their resources during heat stress period could be able to maximize their yield and improve its quality. Best Management Practices results in economic efficiency, effective pesticide resistance management and enhanced crop productivity.