Yield, Boll Distribution and Fibre Quality of Hybrid Cotton (Gossypium hirsutum L.) as influenced by Organic and Modern Methods of Cultivation

Abstract

India is the largest cotton-growing country (8.9 million hectares) in the world and most of the area is raindependent. Large amount of pesticides are used for the control of sucking pests and lepidopterans. Increasing demand for clean organic fibre has led to an interest in organic cotton. However, information on the effects of organic cultivation on fibre quality is limited. Seed cotton yield and fibre quality (length, strength, micronaire and uniformity) were determined for an organic and modern method of cultivation during 3 years (the end of year 11, soil samples were collected and analysed for soil organic carbon content, water-stable aggregates (%), and mean weight diameter. Averaged over 3 years, an additional 94 kg seed cotton ha )1 was produced in the organic over the modern method of cultivation and the difference was significant. The year · treatment interaction was significant. Seed cotton yield in the organic plots was significantly greater than the modern method of cultivation plots in 2003-2004 because of a well-distributed normal rainfall and low pest incidence. The main stem nodes 13-22 accounted for the largest numbers of bolls present on the plant. Plants of the organic plots had significantly (37-71 %) more bolls on nodes 13-27 than those for the plants of the modern method of cultivation. Lateral distribution of bolls on a sympodial (fruiting) branch, was noticed up to fruiting point 11. However, treatment differences were not significant. With regard to fibre quality (length, strength, fineness and uniformity), differences between years were significant. Inferior quality fibre was produced in 2004-2005 because of delayed planting and early cessation of rain. On average, cotton grown under organic conditions compared with the modern method of cultivation had significantly better fibre length (25.1 vs. 24.0 mm) and strength (18.8 vs. 17.9 g tex )1 ). Soil samples of the organic plots had significantly greater C content, water-stable aggregates and mean weight diameter than the modern method of cultivation plots. Differences were restricted to the top layers (0-0.1 and 0.1-0.2 m). Yield benefits of growing cotton in an organic system over the modern method of cultivation are expected to be greater in years receiving normal rainfall and having low pest incidence.

Deconstructing Indian cotton: weather, yields, and suicides

“…The variable dd is the sum of daily degrees of temperature above the developmental threshold for cotton of 12°C (i.e., physiological time) during the growing period. Predicted yields and lack of sizeable PBW populations (not shown) accord qualitatively with long-run field studies on rainfed cotton at Nagpur, MH, roughly 100 km to the NW of Yavatmal [5,35]. Multiple regression of yield on rainfall and dd indicates that only rainfall was a significant predictor of yield at Yavatmal that Fig.…”

“…However, in an 11-year study of rainfed cotton at Nagpur, MH, India (near Yavatmal) using the non-Bt G. hirsutum hybrid NHH-44 under organic and conventional practices, Blaise [5] found higher yields and lower pest damage in organic cotton. Fundamental to understanding this result is that annual emergence of the key pest PBW in spring is poorly timed to attack rainfed cotton and absent high inoculum from irrigated cotton (Fig.…”

“…Cotton was the target of strong selection and adaptation by Indian farmers, but several agronomic changes altered the ecology and economics of cotton production in India as cotton became the raw material for the world's largest manufacturing industry-cotton textiles through the first half of the Industrial Revolution [1]. Starting in 1790, new world cottons (chiefly G. hirsutum L. and later G. barbadense L.) were introduced [2] with F1 hybrid cotton (normally G. hirsutum) introduced in the 1970s [3] ushering in high use of insecticide and fertilizer [4,5]. Planting of transgenic (i.e., genetically modified) F1 hybrid Bt cottons expressing endotoxins of the soil bacterium Bacillus thuringiensis for control of lepidopteran pests began in 2002 [6], and by 2012, more than 1128 Bt hybrid varieties of variable quality were planted on 92 % of the cotton area [2,7].…”

Phenolic compounds of Hibiscus sabdariffa and influence of organic residues on its antioxidant and antitumoral properties

“…The content of phenolic compounds and other phytochemicals present in medicinal plants, as well as in fruits and vegetables, is largely influenced by the type of cultivation, genetic factors, environmental conditions, in addition to the degree of maturation and the variety of the plant (Koleva et al, 2002;Melo et al, 2006). The fact that the highest phenol content was obtained using soil with poultry litter and incorporated organosuper  is due to an improvement in soil physical properties, such as an increased soil water retention (Karamanos et al, 2004); this is in addition to an improvement in the balance of soil nutrients (Blaise, 2006).…”

The role of soil properties and it’s interaction towards quality plant fiber: A review

“…Some example are early stress with subsequent recovery, or higher N fertility and different tillage or rotation systems [79,89], planting date [103], green manure crops [104], irrigation [8] and insect damage causing compensation and later fruit production [105]. Blaise [106] observed better fiber length and strength in the organic cultivation system (OCS) plots compared with the modern method cultivation (MMC). Repeated application of manure and mulch to the OCS plots increases the water holding capacity, infiltration rate and hydraulic conductivity than the MMC and as a result, quality of fiber quality improves in the OCS plots.…”