Effect of some Citrus Rootstocks Types on Growth and Productivity of Gold Nugget Mandarin Trees

Abstract

The present investigation was carried out during two successive seasons (2018/2019; 2019/2020) on almost 12-year old identical Gold Nugget trees (Citrus reticulate, Blanco) (Wilking mandarin x Kincy mandarin), grafted on three rootstocks cultivated in a private orchard located in Al Qalyubia Governorate, Egypt. The trees were grown at a distance of 2 × 6 m in silt soil under the Immersion irrigation system. This investigation aimed to study the effect of some citrus rootstocks on Gold Nugget mandarin trees Growth and Productivity. Three citrus rootstocks were: Troyer citrange Citrus sinensis 'Washington' x Poncirus trifoliate (Tr.), Sour orange (Citrus aurantium L.) (SO.) and Volkamer Lemon (Citrus volkameriana) (VOL). The experiment was designed as a randomized complete block design with five replications. The obtained results showed that Gold Nugget grafted on Troyer citrange rootstock recorded the highest significant values of chlorophyll a, b, total chlorophylls, total carbohydrates, spring growth cycle, fruit set and yield. Whereas Gold Nugget grafted on Sour orange rootstock recorded the highest significant values of shoot thickness, Leaf surface area, Rate Increasing canopy, vitamin C and TSS/ acid ratio. Regarding Gold Nugget grafted on Volkamer lemon rootstock recorded the highest significant values of dray matter percentage, the number of leaves, tree Canopy, summer growth cycle, flowering, fruit Physical properties and acidity percentage.