Journal of Food, Agriculture & Environment, Vol.13 (1), January 2015 71 www.world-food.net Journal of Food, Agriculture & Environment Vol.13 (1): 71-76. 2015 WFL Publisher Science and Technology Meri-Rastilantie 3 B, FI-00980 Helsinki, Finland e-mail: info@world-food.net Physical and histochemical fiber properties of kenaf (Hibiscus cannabinus L.) affected by different water treatments Amir Mahdi Khalatbari, Hawa Z. E. Jaafar *, Amir Ali Khalatbari and Fatemeh Balouei Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia. e-mail: drhawazej.postgrads@gmail.com, amkh_united2002@yahoo.com, magnificent_pal@yahoo.com, farina.balloei@yahoo.com Received 20 April 2014, accepted 30 November 204. Abstract Kenaf (Hibiscus cannabinus L.) is highly considered in the pulp and paper industry and is known as a drought tolerant plant. Application of kenaf fiber has attracted a huge interest in the world due to increased paper consumption and protected tropical forest. The impact of three water treatments on the physical and histochemical properties of three varieties of kenaf (Hibiscus cannabinus L.) namely Fuhong 991 (FH991), V36 and Kohn-Kaen 60 (KK60) relevant to pulp production were investigated. Plants were grown in the glasshouse at Universiti Putra Malaysia (UPM). The water treatments consist of 100% of Evapotranspiration Replacement (ER), 50% of ER (moderate stress) and 25% of ER (severe stress) were imposed on plants for two months and replicated three times in a split plot arrangement based on randomized complete block design (RCBD). Water stress did affect the fiber dimensional and derived values for all three varieties in a negative way. Well-watered varieties V36 and FH991 gained the highest value of bast and core fiber yield, respectively. All varieties of kenaf subjected to 100% of FC watering had the highest value of fiber length and fiber diameter. The fiber morphological data of all kenaf varieties proved that there are differences in their length, diameter, lumen diameter and cell wall thickness as different varieties could be subjected to different water treatments. Key words: Bast fiber, core fiber, fiber length, fiber diameter, cell wall thickness and lumen diameter, histochemical properties. Introduction Kenaf has been used as a cordage crop to produce twine, rope, and sackcloth for over six millennia 9 . Kenaf (Hibiscus cannabinus L.) is one of the important fiber crops next to cotton, which is planted throughout the world. It is cultivated for its core and bast fibers. Unlike cotton, the fiber of kenaf is obtained from vegetative part of plant. Hence, growth and biomass production of kenaf is a fundamental issue that should be considered for its successful commercial cultivation. The length of the growing season, average day and night temperatures and adequate soil moisture are considered the key elements affecting kenaf yields 6 . It is also an important source of textile fibers for the manufacture of twines, ropes, burlap bags and carpet backings using traditional retting ponds in Africa, Asia and Latin America. As a non-woody plant, its stem contains two distinct fiber types, the bast or the outer bark fibers (comparable to softwood fibers), and the inner core of short woody fiber 10 . In addition to fibres, the core pulp contains a significant portion of parenchyma cells and vessel elements compared to the bast pulp, which is mainly fibrous. More recent researches and development works in the 1990s have demonstrated the plant’s suitability for use in building materials, adsorbents, textiles, livestock feed, and fibers in new and recycled plastics 27 . The 30-40% of the stem (bast) can be used for several high value fiber applications 24 , while the 60-70% of the stem (core) can be used for thermochemical process 11, 17 . There has been an increase in interest in growing kenaf throughout the world for its high biomass yield and the elevated fiber content. Kenaf (Hibiscus cannabinus L.), a fast growing C3 plant native of tropical Africa, is being investigated as new source of bioenergy as well as an industrial crop and has high potential to be used. The high biomass yield and the elevated fiber content of kenaf justify the growing interest on this multipurpose crop for its potential role in agroecosystems involving biomass production as substitute of non-renewable resources 7 . The high biomass potential and the low inputs need of the crop has been reported 1 . Although water deficit is known to retard every aspect of growth including yield, water stress is not always injurious, because it has been reported that this type of abiotic stress could improve the quality of plant products like fiber quality sometimes 16 and secondary metabolites 14 . However, the effect of water stress on fiber quality and properties of some varieties of kenaf has not been clearly examined and expounded. The objective of the present study was to examine the effects of three different water treatments based on FC on kenaf fiber yield and quality such as bast and core fiber yield, bast and core ratio, total fiber yield, fiber diameter, fiber lumen diameter, cell wall thickness, fiber length, slender ratio, rankle ratio and eventually coefficient of suppleness.