CC BY
0UNDERSTANDING THE WILT OF COTTON: CAUSES, SYMPTOMS, AND
MANAGEMENT
Mukhammadieva Sh.N.
National University of Uzbekistan named after Mirzo Ulugbek https://doi.org/10.5281/zenodo.11517408 Introduction: Cotton is a crucial global crop that serves as a primary raw material for the textile industry. However, like any other crop, cotton is susceptible to various diseases and environmental stresses that can affect its growth and yield. One significant challenge faced by cotton growers is the occurrence of wilt, a condition that can have detrimental effects on plant health and productivity. The wilt is becoming serious problem for cotton growing farmer and key subject of research in cotton resistance genetics and pathology. This aim of this paper is to call for attention and concentrated action by describing potentially damage of the pest, morphology, symptoms, Epidemiology, behavior, entry pathways and control method. The key pest of cotton accounts for its production loss up to70% in the absence of compatible control measures. Its effective control strongly relies on integrated management strategies includes Bio control agents, Physical, cultural a virulent strains, resistant varieties are the best practices for pest management. Managing wilt is challenging and involves using resistant cultivars and avoiding introducing and spreading the pathogen through the soil, plant material, and equipment. In this article, we will explore the causes, symptoms, and management strategies associated with the wilt of cotton. Wilt disease causes, spread, Verticcillium dahliae Kleb in the majority of field soils where cotton is planted. information about the existence of different types and races of is given in many literary sources. In this case, it is very necessary and useful to create cotton varieties that have tolerant, i.e. polymer gene linked blocks. Research has long been carried out on the identification and study of cotton diseases in Uzbekistan. As an example, the result of K. Baker (1968) and N. S. Mirpulatova's research (1973), on one plant affected by wilt, there are more than 240 thousand microsclerotia of the pathogen[1]. In the conditions of Uzbekistan, cotton varieties Gossypium hirsutumL. and Gossipium barbadense L. are currently cultivated, and infected with fungi by three pathogens of wilt disease -Verticillum dahliaeKlebahn, Fusarium oxysporumf. sp. vasinfectum(Atk.) Snyderet. Hansen and Fusarium verticillioides(Sacc.) Nirenberg ( Syn.: Fusarium moniliformeSheld.), (Marupov et al., 2013)[2]. Sh.E. Namazov emphasized that wilt disease of Verticillium dahlia Kleb strain poses a great threat to the economic value of Uzbekistan's medium-long-fiber cotton varieties[3]. Causes of Wilt in Cotton:
1. Fungal Infections: One of the primary causes of wilt in cotton is fungal infections, with Fusarium and Verticillium species being the most common culprits. These fungi invade the vascular system of the plant, disrupting water and nutrient transport, leading to wilting symptoms.
2. Bacterial Pathogens: Bacterial wilt caused by strains like Xanthomonas axonopodis can also affect cotton plants. Bacteria infiltrate the plant's vascular tissues, causing blockages and impairing the movement of water and nutrients.
3. Environmental Stress: Wilt can also result from environmental factors such as prolonged drought, high temperatures, or poor soil conditions. These stressors compromise the plant's ability to uptake water, leading to dehydration and wilting.
Symptoms of Wilt in Cotton:
1. Leaf Wilting: The most apparent symptom of wilt in cotton is the wilting of leaves. Initially, this may occur on specific branches or sections of the plant and gradually spread if the condition persists. Sometimes partial wilting occurs; where in only one portion of the plant is affected, the other remaining free. The taproot is usually stunted with less abundant laterals.
2. Leaf Yellowing: Infected cotton plants often exhibit yellowing of leaves, indicating a disruption in nutrient uptake and photosynthesis. This further weakens the plant and reduces its overall vigor.
3. Stunted Growth: Wilted cotton plants may experience stunted growth due to reduced water and nutrient availability. This is particularly evident in severe cases, where the plant struggles to develop properly.
4. Vascular Discoloration: In cases of wilt caused by fungal or bacterial infections, the vascular tissues may display discoloration. This can be observed by cutting a cross-section of an affected stem, revealing brown or black streaks.
Management Strategies:
1. Resistant Varieties: Planting cotton varieties with resistance to specific pathogens, such as Fusarium or Verticillium, can be an effective preventive measure. Breeding programs continue to develop new cultivars with enhanced resistance to wilt.
2. Crop Rotation: Implementing a crop rotation strategy helps break the disease cycle by preventing the buildup of pathogens in the soil. Alternating cotton with non-host crops can reduce the risk of infection.
3. Soil Health Management: Maintaining optimal soil conditions, including proper drainage and nutrient levels, can enhance the overall health of cotton plants and reduce their susceptibility to environmental stressors.
4. Fungicide and Bactericide Application: In cases where fungal or bacterial infections are identified, the application of appropriate fungicides or bactericides may help manage the disease. Timely and targeted treatments are crucial for effective control.
5. Irrigation Management: Ensuring proper and timely irrigation is essential to prevent wilt caused by water stress. Drip irrigation or other efficient watering systems can help maintain adequate soil moisture levels.
Table
Size of cotton planting areas, proportion of transgenic cotton and disease prevalence of
Verticillium wilt and Fusarium wilt.
Outbreaks of the disease have been extreme in some years, especially in 2009 but relatively less in recent years. Proportion of transgenic cotton is a measure of the percentage of growing areas of transgenic cotton relative to the total areas of cotton in the surveyed regions (A). Disease prevalence is a measure of the proportion (or percentage) of geographical sampling units (cotton fields) in which the corresponding disease symptoms were observed relative to the total number of geographical sampling units (cotton fields) that were inspected (B). Arrows indicate extraordinary prevalence of cotton diseases. ( Table1).
Total growing areas of cotton Proportion of transgenetic
■ 2000 ■ 2003 ■ 2008 ■ 2014 ■ 2000 ■ 2003 ■ 2008 ■ 2014
Cotton disease rates (%)
Verticilium wilt Fusarium wilt
■ 2000 ■ 2004 ■ 2009 ■ 2010 ■ 2013 ■ 2014 ■ 2000 ■ 2005 ■ 2010 ■ 2013 ■ 2014
Conclusion:
Wilt in cotton poses a significant threat to global cotton production, impacting both yield and fiber quality. Understanding the causes, recognizing symptoms, and implementing effective management strategies are essential for cotton growers to mitigate the impact of wilt on their crops. Through a combination of resistant varieties, good agricultural practices, and timely interventions, farmers can work towards safeguarding their cotton crops from the devastating effects of wilt.
References:
1. BakerK. -AnnualReview of Physiolgy. -1968. -N 6, pp. 263-294.
2. MarupovA., Robert D. Stipanovic, Turamuratova G.H., Mambetnazarov A. B., Marupova M.A.,Fusarium verticillioides: A New Cotton Wilt Pathogen in Uzbekistan. International Open Journal of Plant Disease and Pathology Vol. 1, No. 1, July 2013, PP: 01 -05 Available online at http://acascipub.com/Journals.php
3. Namazov Sh.E. Genetic basis of intraspecific and interspecific complex hybridization in applied cotton breeding. Author's abstract. doc. diss. 2014
