: Diseases incited by soilborne fungi are responsible for reducing the yield and cause significant impact to almost all crops. Among then, Rhizoctonia solani AG-4 is considered the most important in the cotton, common bean and soybean crops in Brazil. The use of diagrammatic scale or rating scales, as a tool to help in the quantification of the severity of a particular disease, is more common for foliar diseases. Considering the lack of a standardized, illustrated and easy-to-apply methodology for assessing the severity of R. solani lesions in cotton, soybean and common bean seedlings, a simple and precise rating scale was developed with the objective to fill this gap. The proposed scale shows four levels of disease severity, with the descriptions and illustrations for each type of lesion observed in the cotton, soybean and common bean seedlings. This developed scale was validated in many experiments and proved to be adequate for severity assessments of R. solani lesions on cotton, soybean and common bean seedlings.

: Diseases incited by soilborne fungi are responsible for reducing the yield and cause significant impact to almost all crops. Among then, Rhizoctonia solani AG-4 is considered the most important in the cotton, common bean and soybean crops in Brazil. The use of diagrammatic scale or rating scales, as a tool to help in the quantification of the severity of a particular disease, is more common for foliar diseases. Considering the lack of a standardized, illustrated and easy-to-apply methodology for assessing the severity of R. solani lesions in cotton, soybean and common bean seedlings, a simple and precise rating scale was developed with the objective to fill this gap. The proposed scale shows four levels of disease severity, with the descriptions and illustrations for each type of lesion observed in the cotton, soybean and common bean seedlings. This developed scale was validated in many experiments and proved to be adequate for severity assessments of R. solani lesions on cotton, soybean and common bean seedlings.

Verticillium wilt caused by soil-borne fungus of Verticillium dahliae Kleb. is one of the most devastating diseases of cotton. Since the hierarchically organized mitogen-activated protein kinase (MAPK) cascade plays pivotal roles in signaling plant defense against pathogen attack, and the key nodes of MAPKKs (MKKs) may serve as for the convergence and divergence of signals in MAPK cascades, the possible relations between MAPK signaling and cotton Verticillium resistance were examined in this study. A total of 24 MKK genes were identified in the Gossypium hirsutum L. genome and then classified based on phylogenetic analysis. Then the regulation roles of all types of cotton MKKs in activation of cotton disease resistance were tested with the virus-induced gene silencing (VIGS) method. The results showed that three types of MKKs (GhMKK4, GhMKK6 and GhMKK9) positively regulate, while GhMKK10 negatively regulate the cotton resistance to Verticillium wilt. Further, more subtle regulation of cotton resistance mediated by MKK genes were revealed. In GhMKK9, only Gh_A12G2448 and Gh_D12G2574 displayed positive regulation of cotton resistance; whereas only Gh_A12G1883 and Gh_D12G2062 displayed negative regulation of cotton resistance in GhMKK10. All these results show that MKK members in MAPK signal cascades play dual roles in subtly regulating of cotton resistance to Verticillium wilt.

Fusarium wilt is one of the most serious diseases affecting cotton. However, the pathogenesis and mechanism by which Fusarium oxysporum overcomes plant defence responses are unclear. Here, a new group D mitogen‐activated protein kinase (MAPK) gene, GhMPK20, was identified and functionally analysed in cotton. GhMPK20 expression was significantly induced by F. oxysporum. Virus‐induced gene silencing (VIGS) of GhMPK20 in cotton increased the tolerance to F. oxysporum, whereas ectopic GhMPK20 overexpression in Nicotiana benthamiana reduced F. oxysporum resistance via disruption of the salicylic acid (SA)‐mediated defence pathway. More importantly, an F. oxysporum‐induced MAPK cascade pathway composed of GhMKK4, GhMPK20 and GhWRKY40 was identified. VIGS of GhMKK4 and GhWRKY40 also enhanced F. oxysporum resistance in cotton, and the function of GhMKK4–GhMPK20 was shown to be essential for F. oxysporum‐induced GhWRKY40 expression. Together, our results indicate that the GhMKK4–GhMPK20–GhWRKY40 cascade in cotton plays an important role in the pathogenesis of F. oxysporum. This research broadens our knowledge of the negative role of the MAPK cascade in disease resistance in cotton and provides an important scientific basis for the formulation of Fusarium wilt prevention strategies.

Recently, mosquito repellent textile materials are increasingly in demand from consumers as a preventive measure from mosquito-borne diseases like malaria, dengue. Mosquito repellent-treated textile material initially shows good repellency against mosquitoes but upon repeated washing cycles this effect gets washed off considerably. In the present work, 4-Amino-N, N-diethyl–3-methyl benzamide (MD) is synthesized from N, N-diethyl-m-toluamide (DEET) and it is used as base material for synthesis of azo group. This synthesized base MD was then coupled with three different napthols to get dyed cotton fabric using diazotization process. This dyed cotton fabric has imparted mosquito repellent finish in one, single operation of dyeing cum finishing. This approach is based on modification of universally used mosquito repellent and synthesizing an azo group-based dye in the fibre matrix of the cotton fabric. The chemical structures of the MD were characterized using FT-IR and ¹H-NMR spectroscopy. The fastness properties of the dyed cum finished fabric were measured to evaluate the performance of the dyed fabric. Efficacy of mosquito repellency of the dyed cotton fabric was studied using standard methods. The dyed cotton fabric using napthols and MD showed very good and durable mosquito-repellent activity.

Cotton leaf curl Multan virus (CLCuMuV), in conjunction with cotton leaf curl Multan betasatellite (CLCuMuB), causes cotton leaf curl disease in South Asia. CLCuMuV-CLCuMuB was first found in 2006 to be associated with a leaf curl disease of Hibiscus rosa-sinensis in China. Recently, CLCuMuV-CLCuMuB has become prevalent in H. rosa-sinensis in the southern part of the country. Here, we identified CLCuMuV-CLCuMuB in H. sabdariffa for the first time. To our knowledge, H. sabdariffa is the fourth seed-propagated plant in China to be affected by CLCuMuV-CLCuMuB.

Alternaria leaf spot (ALS, caused by Alternaria spp.) is one of the most common foliar diseases in cotton (Gossypium spp.) that occurs in most cotton-growing regions of the world including the United States. In New Mexico, ALS caused by A. alternata (Nees:Fr.) Keissler is becoming prevalent due to favorable weather conditions in the late cropping season; however, there is limited information on screening cotton for ALS resistance. In this study, a total of 125 Upland cotton (G. hirsutum L.) genotypes were separated into 5 trials each with 32 entries and 3–4 replications, together with one trial including 8 Pima cotton (G. barbadense L.) cultivars and lines with 4 replications in 2016. Three additional field trials each with 32 or 34 genotypes and 4 replications were conducted in 2017. Based on the high disease incidence (99.9% with a range of 90–100% in 2016 and 100% in 2017) and high disease severity index (DSI, 26.7–92.0 with a mean of 62.4 in 2016 and 42.0–89.0 with a mean of 66.7 in 2017) of foliar symptoms in the late growing season in both years, no cotton genotype was immune to ALS (A. alternata) under the natural infection field conditions. The analysis of variance showed that there were significant genotypic variations in six of the nine replicated trials, and the broad-sense heritability estimates for DSI ranged from 0.489 to 0.702 with an average of 0.566. No significant genotypic difference was detected among Pima cotton cultivars and lines in both years. An orthogonal contrast detected no overall significant difference between Upland and Pima cotton in both years, while 15 Upland glandless lines as a group, had a significantly lower DSI than the glanded group with 17 Upland lines in one replicated test. Glandless NuMex COT 15 GLS, NM 13P1117 and NM 12Y1002, and glanded commercial transgenic FM 2484 B2F, PHY 444 WRF and NG 4545 B2XF were consistently resistant to ALS in two or more tests. The results provide useful information for breeding cotton for ALS resistance.

Susceptibility and declined resistance to human pathogens like respiratory syncytial virus (RSV) at old age is well represented in the cotton rat (Sigmodon hispidus). Despite providing a preferred model of human infectious diseases, little is known about aging of its adaptive immune system. We aimed to define aging-related changes of the immune system of this species. Concomitantly, we asked whether the rate of immunological alterations may be stratified by physiological aberrations encountered during aging.With increasing age, cotton rats showed reduced frequencies of T cells, impaired induction of antibodies to RSV, higher incidence of aberrations of organs and signs of lipemia. Moreover, old animals expressed high biological heterogeneity, but the age-related reduction of T cell frequency was only observed in those specimens that displayed aberrant organs. Thus, cotton rats show age-related alterations of lymphocytes that can be classified by links with health status.