Towards sustainable landscape: Feasibility of using different cheese whey types in the fertigation of Schinus molle L. seedlings

Cheese whey (CW) reuse for agricultural purposes is an important management strategy. A pot experiment was carried out to examine the feasibility of using different CW types in the fertigation of Schinus molle L. plant by assessing their effects on seedling growth, chemical constituents and histological structure. The study was conducted at Faculty of Agriculture, Cairo University, Egypt, during seasons of 2014/2015 and 2015/2016. Four CW types were undiluted or diluted with tap water (TW) for fertigation as follows (CW:TW v/v): Kareish cheese non salty whey (KCNSW) at 1:0 and 1:1, Mozzarella cheese non salty whey (MCNSW) at 1:0 and 1:1, Mozzarella cheese salty whey (MCSW) at 1:6 and 1:8, and Domiati cheese salty whey (DCSW) at 1:12 and 1:16. Control plants were irrigated with TW only. Diluted CW treatments showed positive effects on seedling height, leaves and main roots number/seedling, leaf area, as well as leaves and roots dry weights, in addition to their favorable impacts on N, P, K, Ca, Na, Cl, total carbohydrate, and proline contents. Furthermore, ON treatments influenced lamina and midrib thicknesses, midrib main vascular bundles length and width, and oil glands diameter and number. Among all tested CW fertigation treatments, seedlings showed the best performance under DCSW (1:16), followed by DCSW (1:12) > MCSW (1:8) > MCSW (1:6), respectively. A reduction of the studied parameters was recorded by undiluted CW treatments; however, it could be alleviated by CW dilution. Usage of CW in fertigation is shown to be a suitable option to most cheese producing regions, where CW disposal could be a challenge. Furthermore, it is applicable to sustainable landscape where the objective of zero waste is the main goal. As a way to develop the landscape without jeopardizing the environment, a sustainable approach is proposed for ornamental trees fertigation using CW in areas close to cheese factories. (C) 2019 Elsevier Ltd. All rights reserved.