S.B. Hussain, M.A. Anjum, S. Hussain, S. Ejaz and H.M. Kamran
Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan 60800, Pakistan

SUMMARY Introduction � Citrus occupies a prominent position in the world fruit industry. Quality of citrus fruits is affected by various biotic and abiotic factors. Among these, climatic factors may have some significant influence that this study investigated. Materials and methods � The fruits of two mandarin cultivars (�Kinnow� and �Feutrell�s Early�) grown under different agro-climatic conditions of the Province Punjab, Pakistan were evaluated for their physico-chemical characteristics. The experiment was conducted in five locations (Multan, Sahiwal, Faisalabad, Sargodha and Chakwal), at a distance of 100�150 km of each other. Fruit quality assessment included physical and biochemical attributes. Results and discussion � The physico-chemical characteristics of fruits presented significant differences between the two cultivars. Both mandarin cultivars gave the maximum average fruit weight, diameter, peel thickness, number of seeds per fruit, seed and rag contents at Chakwal, whereas fruits harvested at Sahiwal showed higher peel thickness as compared with those from the other locations. The maximum juice content was obtained in the fruit from Faisalabad and Sargodha. �Kinnow� fruit attained the maximum total soluble solids (TSS) at Sargodha, followed by those from Faisalabad and Chakwal. Moreover, less acidity was recorded in �Kinnow� fruit harvested from Sargodha. The maximum sugar content was recorded in �Kinnow� fruit harvested from Faisalabad, followed by those from Chakwal. �Feutrell�s Early� mandarin juice from Chakwal showed higher vitamin C content. Total phenolic content (TPC) varied among cultivars, the maximum TPC of �Kinnow� and �Feutrell�s Early� were found in the fruits from Sahiwal and Multan, respectively. Conclusion � The mandarin cultivars produced in the agro-climatic conditions from Faisalabad to Sargodha expressed a high fruit quality, so that this area can be recommended for a commercial production. Résumé Les conditions agro-climatiques affectent la qualit� des fruits du mandarinier (Citrus reticulata Blanco). Introduction � Les agrumes occupent une place de choix dans l�industrie mondiale du fruit. La qualit� des agrumes est affect�e par divers facteurs biotiques et abiotiques. Parmi ces derniers, les facteurs climatiques doivent avoir une influence notable que cette �tude a permis d�appr�cier. Mat�riel et m�thodes � Les fruits de deux cultivars de mandarinier (�Kinnow� et �Feutrell's Early�) cultiv�s sous diff�rentes conditions agro-climatiques de la province du Penjab, au Pakistan, ont �t� �valu�s pour leurs caract�ristiques physico-chimiques. L�exp�rimentation a �t� men�e dans cinq sites (Multan, Sahiwal, Faisalabad, Sargodha et Chakwal), � une distance de 100 � 150 km les uns des autres. L��valuation de la qualit� des fruits comprenait des attributs physiques et biochimiques. R�sultats et discussion � Les caract�ristiques physico-chimiques des fruits ont pr�sent� des diff�rences significatives entre les deux cultivars. Les deux cultivars ont pr�sent� des moyennes maximales du poids d�un fruit, du diam�tre, de l��paisseur de la peau, du nombre de graines par fruit, et de teneur en p�pin et en m�socarpe dans les fruits produits sur le site de Chakwal, alors que ceux r�colt�s � Sahiwal ont pr�sent� une �paisseur de la peau plus �lev�e par rapport aux fruits des autres sites. La teneur maximale en jus a �t� obtenue pour les fruits de Faisalabad et Sargodha. Les fruits du cv. Kinnow ont �t� les plus riches en mati�res solubles totales (TSS) en provenance de Sargodha, suivi de ceux issus de Faisalabad et de Chakwal. Une moindre acidit� a �t� enregistr�e dans les fruits de 'Kinnow' r�colt�s � Sargodha. La teneur maximale en sucre a �t� enregistr�e pour les fruits de �Kinnow� r�colt�s � Faisalabad, suivis par ceux cultiv�s � Chakwal. Le jus des mandarines �Feutrell's Early� cultiv�es � Chakwal avait une teneur en vitamine C �lev�e. La teneur en compos�s ph�noliques totaux (TPC) variait entre les cultivars, le maximum pour �Kinnow� et �Feutrell's Early� ayant �t� trouv� dans les fruits de Sahiwal et Multan, respectivement. Conclusion � Les cultivars de mandarinier produits dans les conditions agro-climatiques entre Faisalabad et Sargodha ont exprim� une qualit� �lev�e des fruits, de sorte que cette zone peut �tre recommand�e pour une production commerciale. Keywords Pakistan, Punjab, mandarin, Citrus spp., fruit quality, physico-chemical characteristics, phenolics Mots clés Pakistan, Penjab, mandarinier, agrumes, qualit� du fruit, caract�res physico-chimiques, compos�s ph�noliques

Significance of this study What is already known on this subject? Agro-climatic conditions influence the different quality parameters of fruit. Mandarin (Citrus reticulata Blanco) cultivars have major commercial importance in the citrus industry of Pakistan. Different citrus cultivars are grown on limited/specific areas of country as a commercial fruit crop. What are the new findings? In terms of fruits physico-chemical characteristics, the mandarin cultivars performed better in the agro-climatic conditions from Faisalabad to Sargodha, so that this area is recommended for their commercial production. What is the expected impact on horticulture? A bigger window of better quality fruit production for fresh and processed citrus industry is expected in Pakistan from the plantation of commercial citrus groves in explored potential areas in the future. Overall, potential citrus growing areas provide a base for expansion of citrus industry in national and international fruit markets.

E-mail: sajjad.hussain@bzu.edu.pk  

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Received: 15 February 2017 | Accepted: 30 August 2017 | Published: 1 December 2017 | Available online: 1 December 2017