Field Crop 2024, Vol.7, No.3, 134-144 http://cropscipublisher.com/index.php/fc 136 iron significantly affect cotton yield and disease susceptibility (Singh et al., 2010). At the same time, the significant impact of different consecutive planting years on the abundance of bacterial taxa in the two soils also provides an important reference for studying changes in soil microbial communities over time (Figure 1) (Ma et al., 2023). Figure 1 Cladograms of cotton field soil samples bacterial taxa with different continuous cropping years in AKS (A) and SHZ (B) soils based on linear discriminant analysis effect size (LEfSe) (Adopted from Ma et al., 2023) Image caption: The image consists of two circular dendrograms (A and B), each depicting the taxonomic distribution of different microbial communities. These dendrograms are likely representing bacterial phylogenetic relationships and their abundance across various samples (Adopted from Ma et al., 2023) 3.3 Seed quality and treatment The quality of seeds and their treatment before planting are crucial in managing seedling diseases. Seeds that are chemically coated or treated with fungicides can reduce the incidence of diseases by protecting the seedlings from pathogen attacks. The type of seed and its genetic resistance to diseases also play a role in determining the overall health and yield of the cotton crop. Studies have shown that the use of high-quality seeds and appropriate seed treatments can mitigate the adverse effects of environmental and soil conditions on seedling diseases (Singh et al., 2010; Dhage and Garg, 2021). 4 Impact of Seedling Diseases on Crop Establishment 4.1 Seedling mortality rates Seedling diseases significantly impact cotton crop establishment by increasing seedling mortality rates. Various studies have shown that different tillage practices and environmental conditions can influence the incidence and severity of these diseases. For instance, stale seedbed production was found to increase the incidence and severity of seedling diseases in cotton, although the effect was minimal and manageable with in-furrow fungicides (Colyer and Vernon, 2005). Additionally, the use of winter legume cover crops was shown to affect soilborne pathogens, with some cover crops reducing the isolation frequency of pathogens like Thielaviopsis basicola, while others increased populations of Rhizoctonia spp. and Pythium spp. (Khan et al., 2017). These findings highlight the variability in seedling mortality rates depending on the agricultural practices employed. 4.2 Effects on plant vigor and growth Seedling diseases not only increase mortality rates but also adversely affect the vigor and growth of surviving plants. Thrips, for example, are known to cause significant damage to cotton seedlings, leading to stunted growth, reduced leaf area, and compromised root development (Cook et al., 2011). Similarly, the presence of soilborne pathogens such as Rhizoctonia solani and Pythiumspp. can lead to root and hypocotyl necrosis, further impairing plant growth (Knight et al., 2015). The use of fungicides and insecticides has been shown to mitigate some of
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