Root induction in Chico (Achraszapota), Pear ( Pyruscommunis L.) and Persimmon (Diospyrus Virginia L.) as affected by IBA and NAA

Abstract

Plant regulating substances has been found to affect varied physiological activities of plants. Theoretically, the list includes almost every process in plant development such as control of rooting, flowering, fruit development, senescence, overcoming environmental stress, control of germination and dormancy, increasing plant resistance to pest, and many others. One of the oldest uses for plant growth regulators (synthetic compounds or plant hormones that modify plant physiological processes) has been to initiate or accelerate the rooting of cuttings. The rooting of cuttings has been shown to be influenced by auxin, a general term used to denote substances that promote elongation in shoot cells such as indoleacetic acid (IAA), indolebutyric acid (IBA), napthaleneacetic acid (NAA). In the cutting, which is a portion of plants such as stems, leaf bud, or root which is separated from plants and induced to form roots of its own, the natural auxin produced in young leaves and buds moves naturally down the plant and accumulates at the cut base along with sugars and other food materials. The natural formation of fruits is apparently triggered by the accumulation of an optimum auxin level in relation to these substances. In a wide variety of plants, rooting is markedly increased by addition of synthetic auxin. Other auxins have a very narrow effective range of concentrations. Concentrations below the critical level are ineffective in root initiation whereas those above the critical level not only inhibit both root growth and bud development but may cause morphological injury. Plant regulating substances have been found to affect varied physiological activities of plants. One of the oldest uses for plant growth regulators (synthetic compounds or plant hormones that modify plant physiological processes) has been to initiate or accelerate the rooting of cuttings (Nickell, 1986). The rooting of cuttings has been shown to be influenced by auxin, a general term used to denote substances that promote elongation in shoot cells such as indoleacetic acid (IAA), indolebutyric acid (IBA), napthaleneacetic acid (NAA). In order to stimulate rooting in chico, pear and persimmon cuttings, 2 commercially prepared hormones were used to soak the cuttings of these fruit-bearing trees. These hormones are IBA and NAA. Cuttings were soaked for 24 hours in three different concentrations of hormones (100 ppm, 200 ppm and 300 ppm) prior to their insertion in the rooting media. The experimental method of research was utilized in this study. The Randomized Complete Block Design (RCBD) was used to determine if there were significant differences among the means. The dilutions were the main factors that were studied while time in terms of number of weeks was utilized for the blocks. The following findings can be drawn from the study: 1.Different dilutions of IBA had no significant effect on: a. the number of roots of chico stem cuttings. b. the length of roots of chico stem cuttings. c. the time between application and root appearance of chico stem cuttings. 2. Different dilutions of NAA had no significant effect on: a. the number of roots of chico stem cuttings. b. the length of roots of chico stem cuttings. c. the time between application and root appearance of Chico stem cuttings. 3. Different dilutions of IBA had no significant effect on: a. the number of roots of pear stem cuttings. b. the length of roots of pear stem cuttings. c. the time between application and root appearance of pear stem cuttings. 4. Different dilutions of NAA had no significant effect on: a. the number of roots of pear stem cuttings. b, the length of roots of pear stem cuttings. c. the time between application and root appearance of pear stem cuttings. 5. Propagating persimmon through stem cuttings using different dilutions of IBA did not succeed as far as the experiment is concerned. 6. Propagating persimmon through stem cuttings using different dilutions of NAA did not succeed as far as the experiment is concerned. The following conclusions can be drawn from the study: 1. Different dilutions of IBA can promote root induction in chico and pear stem cuttings but not in persimmon. 2. Different dilutions of NAA can promote root induction in chico and pear stem cuttings but not in persimmon. 3. Different dilutions of IBA have similar effects in the length of roots in chico and pear stem cutting. 4. Different dilutions of NAA have similar effects in the length of roots in chico and pear stem cuttings. 5. Different dilutions of IBA did not induce root production in persimmon. 6. Different dilutions of NAA did not induce root induction in persimmon. On the basis of positive findings, it is recommended that: 1. Higher dilutions of IBA and NAA may be used again in the future. IBA and NAA in combination are recommended for future studies. 2. It is recommended in pear stem cuttings that lower dilutions of NAA may be tried in the future. 3. It is also recommended for future researches that a comparison of using a powder or talc form from a dilution of hormones (IBA and NAA) be made to find out if there is significant difference in inducing root growth in pear stem cuttings. 4. Time should be increased or prolonged in studying chico stem cuttings using the hormones IBA and NAA. 5. Time should be increased or prolonged in studying pear stem cuttings using the hormones IBA and NAA. 6. other recommendations: a. A research be made to find out particular medium is chico most suitable when propagating thru cuttings. b. A when conducting a future study on cuttings, great care should be taken into consideration of the test planting material. c. A study be made on monitoring the growth of cuttings propagated in a glass house to its full maturity, outside the glass house without now the use of intermittent mist.