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Salinity has become a major environmental concern of agricultural lands, impairing crop production. The current study aimed to examine the role of zinc oxide nanoparticles (ZnO NPs) in reducing the oxidative stress induced by salinity and the overall improvement in phytochemical properties in barley. A total of nine different barley genotypes were first subjected to salt (NaCl) stress in hydroponic conditions to determine the tolerance among the genotypes. The genotype Annora was found as most sensitive, and the most tolerant genotype was Awaran 02 under salinity stress. In another study, the most sensitive (Annora) and tolerant (Awaran 02) barley genotypes were grown in pots under salinity stress (100 mM). At the same time, half of the pots were provided with the soil application of ZnO NPs (100 mg kg–1), and the other half pots were foliar sprayed with ZnO NPs (100 mg L–1). Salinity stress reduced barley growth in both genotypes compared to control plants. However, greater reduction in barley growth was found in Annora (sensitive genotype) than in Awaran 02 (tolerant genotype). The exogenous application of ZnO NPs ameliorated salt stress and improved barley biomass, photosynthesis, and antioxidant enzyme activities by reducing oxidative damage caused by salt stress. However, this positive effect by ZnO NPs was observed more in Awaran 02 than in Annora genotype. Furthermore, the foliar application of ZnO NPs was more effective than the soil application of ZnO NPs. Findings of the present study revealed that exogenous application of ZnO NPs could be a promising approach to alleviate salt stress in barley genotypes with different levels of salinity tolerance.

Cotton (Gossypium hirsutum L.) is an important fibre crop and a major contributor to Pakistan's foreign exchange earnings. It supplies 1,240 ginning mills and 453 textile units consisting of 50 composite and 403 spinning units. Approximately 68% of the country's total exports are linked directly or indirectly with cotton and it employs 40% of the total workforce in the manufacturing sector (Anon, 2004). The multiplier effect of employment in this sector is enormous and is currently fuelling the countries economy. In 1991-92, Pakistan achieved a record production of 12.8 million bales of cotton. In 1992-93 production fell to 9.1 million bales AbstractThe effect of cotton leaf curl disease found at Burewala (Pakistan) on the ginning out turn (GOT) and the physical and chemical characteristics of cotton fibre was evaluated by comparing healthy and cotton leaf curl disease (CLCuD)-infected plants of four cotton varieties. A highly susceptible response to CLCuD was found in all varieties tested. The disease incidence ranged from 42.6 to 81.4%. Significant differences were observed between the fibre of healthy and diseased cotton plants, of all varieties, for GOT, fibre length, fibre uniformity index, short fibre index, fibre fineness, fibre bundle strength, reflectance degree (Rd-value), yellowness (+b value) and maturity ratio. The cv. CIM-473 exhibited the highest reduction in all the quality parameters studied with the exception of Rd-value which was the lowest in cv. NIAB-999. The disease also significantly affected cellulose, protein, wax and pectin content. CLCuD adversely deteriorated the cotton fibre characteristics, however the varietal difference exists. The varieties with less deteriorated fibre by CLCuD should be an essential criterion for the selection of resistant germplasm against CLCuD.Additional key words: Begomovirus, Burewala strain, CLCuD, fibre deterioration, Gossypium hirsutum. ResumenComunicación corta. Deterioro en las fibras de algodón causado por la enfermedad del enrollado de la hoja del algodón En Burewala (Paquistán) se evaluó el efecto de la enfermedad del enrollado de la hoja del algodón (CLCuD) sobre el porcentaje de hilas en las semillas (GOT) y las características físico-químicas de la fibra de algodón, comparando cuatro variedades de plantas de algodón sanas y con la enfermedad. Todas las variedades estudiadas fueron altamente susceptibles a CLCuD. La incidencia a la enfermedad varió entre el 42,6 y el 81,4%. Se observaron diferencias significativas entre las fibras de las plantas sanas y enfermas, en todas las variedades, para GOT, longitud, índice de uniformidad, índice de fibras cortas, finura, fuerza de los paquetes de fibras, reflectancia (valor Rd), amarilleamiento (valor +b) y madurez de las fibras. El cv. CIM-473 fue el que más redujo los parámetros de calidad estudiados, a excepción del valor Rd, que fue menor en el cv. NIAB-999. La enfermedad también afectó significativamente al contenido en celulosa, proteínas, ceras y pectinas. Las variedades con fibras menos deteriorad...