Improving Survival and Orchard Performance of “Costata” Persimmon Seedlings by K-NAA and IBA Applications

Abstract

The present investigation was conducted during the 2018 and 2019 growing seasons on one-year-old persimmon seedlings cv. “Costata” grafted on “Seedy” and “Tarabouls” rootstocks in order to improve its survival percent and orchard perfoprmance. The Seedlings were treated with K-NAA or IBA either by dipping at 3000 mg l-1 for 5 seconds or soaking at 500 mg l-1 for 24 hours. Obtained results generally showed significant increase in vegetative growth, root biomass and leaf chlorophyll and mineral content by all K-NAA and IBA applications compared to the water treated ones. A highest values of sprouting buds percent (during April, June and August), average shoots number, trunk cross-sectional area, leaf area and canopy volume were recorded with the K-NAA soaking at 500 mg l-1for 24 h. Leaf chlorophyll content was highest with K-NAA and IBA soaking in the first season, while K-NAA soaking at 500 mg l-1 for 24 h gave the highest values of leaf N, P, K, Fe, Mn and Zn in both seasons. Also, the K-NAA soaking or dipping applications recorded the highest values of average shoot length, increment percnts of shoot length and stem diameter and highest seedlings survival in both seasons. The K-NAA soaking at 500 mg l-1 for 24 h gave the highest significant values of root biomass in the first season. Results also showed that seedlings on “Seedy” rootstock surpassed the ones on “Tarabouls” rootstock in all vegetative growth parameters and root biomass, but contained lower leaf N, P, Mn and Zn.