ROOTING OF CARRIZO AND TROYER CITRANGE STOCKS, AN ALTERNATIVE FOR THEIR PROPAGATION.

Abstract

The rooting of CTV tolerant Carrizo and Troyer citrange stocks was evaluated using different growth promotors on leafed semi-harwood stem cuttings, cut before the summer heat flux, from 39 month old plant stocks. The efficacy of three rootings promotors was evaluated: the two reagent compounds NAA - Naphthalene acetic acid and IBA - indol butyric acid (at 0,5000 and 7500 mg/lt) and the commercial product Radix 10000 (indol-butyric-acid) (at 0,50 and 75%). Treatments were distributed on the field following a 2³ factorial arrange within a randomized block design. The stocks were maintained within a controlled environment with relative humidity from 95 to 100%, rooting chamber temperature from 24° to 35.8°C and a substrate temperature of 23.8°C at a 10 cm depth. After 56 days from the application of treatments, a general stoke rooting mean of 73% was achieved, with means of 67 and 79% for Carrizo and Troyer citranges, respectively. The rooting efficacy was 82.0, 73.6 and 63.3% for NAA, IBA and Radix, respectively. The best rooting promotor for both citranges was NAA, at the rates of 7500 and 5000 mg/lt, respectively; 100% of rooting with means of 10.4 and 7.8 roots per stock, respectively, were obtained in Troyer; 88 and 96% of rooting with means of 8.9 and 8.0 roots per stock, respectively, in Carrizo. Stake's survival was related to the amount of roots.