Abstract:
Begomoviruses are the most damaging plant pathogens that effect the economical important crops including cotton, cassava, and tomato etc., in the world. Ornamental plants are considered as a reservoir for economically important begomoviruses. Leaf samples of ornamental plants, Hibiscus rosa sinensis, Hibiscus shizuki, Iresine and Ageratum, showing leaf curl and vein thickening symptoms were collected from areas around Lahore and Islamabad during 2017-2018. Their total DNA was extracted by Cetyle Trimethyl Ammonium Bromide (CTAB) method and subjected to diagnostic PCR using universal set of primers. All samples except for Ageratum gave expected size band between 1.1 to 2.8kb. Amplification PCR products of 1.5kb and 1.4kb were obtained using primer pair WTGF/WTGR and Beta01/Beta02 primer, respectively from two samples; Hibiscus rosa-sinensis (isolate AY1) and Hibiscus shizuki (AY2). The products were T/A cloned and sequenced. The nucleotide sequence of isolate AY1 shared 96% (over a stretch of 719/749 nucleotide) identity with cotton leaf curl Kokhran virus – Burewala while isolate AY2 showed 93% (over a stretch of 920/990 nucleotide) nucleotide sequence identity with cotton leaf curl Multan betasatellite. The present study concluded that Hibiscus rosa-sinensis and Hibiscus shizuki are reservoir host of Cotton leaf curl Kokhran virus which are major cause of cotton leaf curl disease in Pakistan, India and China. It is recommended to avoid cultivation of Hibiscus species in cotton growing regions to avoid virus pressure in cotton plants
