*2.1.2 Pathogens*

Different fungi, bacteria and viruses are the major pathogens in cotton farming system [14]. Bacterial blight is one of the notorious disease of cotton crop caused by bacteria, *Xanthomonas citri* pv. Malvacearum; most damaging and vital cotton



*Source: Cotton Production, First Edition. Edited by Khawar Jabran and Bhagirath Singh Chauhan. © 2020 John Wiley & Sons Ltd. Published 2020 by John Wiley & Sons Ltd.*

#### **Table 1.**

*Major chewing pests of cotton.*




*Source: Cotton Production, First Edition. Edited by Khawar Jabran and Bhagirath Singh Chauhan. © 2020 John Wiley & Sons Ltd. Published 2020 by John Wiley & Sons Ltd.*

#### **Table 2.**

*Major piercing sucking pests of cotton.*

diseases caused by bacteria [55]. Bacterial blight affected the cotton crop in worst manner resulting in defoliation of the plants, stems becomes dark and swollen and even detached that ultimately leads to decrease of fiber quality, decreased coloration and death of plant [56]. Fungal diseases of cotton crop are also much more dynamic caused by various fungal pathogens, for example, *Fusarium oxysporum* is responsible to cause Fusarium wilt of cotton [57], *Verticillium dahlia* cause Verticillium wilt of cotton [58], *Colletotrichum gossypii* cause anthracnose of cotton while *Colletotrichum gossypii* var. cephalosporioides is reason for ramulosis [59], *Mycosphaerella areola* source root ramularia gray mildew [60]. The root rots of cotton crop are started by *Sclerotium rolfsii* and *Rhizoctonia solani* [61], *Alternaria macrospora* leads to leaf blight disease [62], while leaf spot of cotton caused by *Cercospora gossypina* [63] and the target spot of cotton caused by *Corynespora cassiicola* [64]. The viral diseases of cotton crop mainly includes viruses from Begomovirus family, Begomovirus acts as foundation for disease spread in cotton crop which commonly includes curl disease, leaf crumple and cotton mosaic disease [65]. While as cotton blue disease and atypical cotton blue disease introduced by Polerovirus [66, 67]. Viral diseases of cotton crop are insect transmitted and need vector for transmission in general [65].
