Cotton reddening: A red signal to Pakistan Economy

Cotton crop is the main stay of Pakistan economy. The growers of Pakistan are suffering huge losses in yield and quality of cotton crop due to various diseases and unaccepted maladies every year. During the previous decade, cotton production experienced many ups and downs. It was at its lowest during the period when it passed through its most serious crisis in the form of cotton leaf curl virus (CLCuV).

Recently, a new mysterious malady, commonly known as ‘reddening’ or ‘red-leaf-disease’ is now emerging very speedily and become a serious problem in various cotton growing belts of Pakistan especially in Sindh. The PCCC also observed the new emerging problems like

• stunning of cotton growth
• wilting of the plants
• reddening of cotton leaves

These are the symptoms endangering the cotton production in Sindh. Thousand acres of cotton crop were found to be affected by this complex in major cotton growing belts of Sanghar, Mirpurkhas Nawabshah, Khairpur, Naushero Feroze and other districts of Sindh.

This mysterious cotton disorder is known as bronze wilt and was first appeared in the USA, Brazil, Argentina, and Bolivia during the hot summers of 1995, 1996, and 1998. Similar disease symptoms were seen in peanuts and soybeans.

"The exact cause of the disorder has yet to be unknown". Both biotic andabiotic factors have been proposed as possible causative agents. Generally it has been believed that plausible cause of bronze wilt is high concentrations of certain strains of Agrobacterium spp. (Agrobacterium tumefaciens), a soil and seed bacterium, that cause damage to the secondary roots. Differences in resistance to bronze wilt are influenced by cultivar, environment (temperature, light intensity, and photoperiod), production practices and abiotic stresses (high temperature and water stress), soil type and fertility, relative nitrogen content of fertilizer and fertilizer ratio of phosphorous and potassium. Potassium deficiency frequently has been mentioned as a primary suspect. Plant age, fruit set and load, earliness in fruiting and maturity, and high yield potential also effect symptom severity.