A Combination of Wounding, IBA and NAA Resulted in Better Rooting and Shoot Sprouting in White Adriatic Fig (Ficus Carica L.) Stem Cuttings

Introduction

Fig (Ficus carica L.) is one of the most important deciduous fruit trees grown in Egypt. It is believed to be indigenous to the Mediterranean where dryer warm temperature climates are dominant. It has been cultivated for thousands of years and mentioned in the holly Muslim book (Quran) and other religion books [1].

It is well known that fig trees are almost propagated by cuttings. However, some of fig varieties are considered semi and hard-to-root such as Conadria, White Adriatic, Kadota and Roxo de Valinhos [2]. Tekintas and Seferoglu [3] reported that the rooting performance ratios of hardwood cuttings of Bursa Siyahi cultivar of figs planted in sand and soil production parcels and perlite and peat filled holes were 71%, 24%, 31% and 21% respectively. Average number of roots (42.75%) and root length (29.25 cm) of Bursa Siyahi cutting were obtained in sandy media.

Different wounding methods were conducted for increasing root production in several plant species. In some plant species, root production on stem cuttings may be promoted by wounding the base of cuttings. A vertical cut with the tip of a sharp knife down each side of the cutting for one inch or two, penetrating through the bark and into the wood may be enough [4].

Auxins such as IAA, IBA & NAA have been traditionally applied to improve rooting of fig stem cuttings. The beneficial effect of IBA & NAA on root ability of fig cuttings was reported by several workers [5, 6, 7, 8, 9]. In this connection, Ali [10] studied the effect of IBA or IAA at (2000 and 4000 ppm) or NAA at (500 and 1000ppm) on root ability of stem cuttings of Sultani fig and reported that treating the cutting with 2000 or 4000 IBA and 4000 IAA gave the highest significant number of roots per cutting after 8 months from culturing under field conditions. Moreover, the highest roots length per cutting was obtained when cuttings were treated with 2000ppm IBA, 4000ppm IBA, 4000ppm IAA and 1000ppm NAA. Moreover, Chalfun, et al. [11] using fig cv. Roxo de Valinhos found that, the cuttings obtained from one-year-old branches of adult fig trees every fortnight between April and August and treated with IBA (100 mg/litre) for 24 h. and cultured in mixture of soil and sand at 3:2 ratio (v/v) gave the highest percentage of rooted cuttings in cuttings collected during April and May (92.5% without IBA and 100% with IBA). The highest percentage of cuttings which sprouted and rooted were obtained with cuttings that were collected early. The application of IBA increased the dry matter weight of shoots and roots. However, the increment in shoot and root dry matter contents due to IBA application decreased with the delay in the collection of cuttings. Also, Karadeniz [12] evaluated the rooting performance of 3 local fig cultivars (Siyah, Patlcan and Kabak). Hardwood cuttings 25-30 cm long obtained from one-year-old branch, treated with IBA (1000 or 2000 ppm) and planted in perlite from the end of October to the end of March, that the highest rooting percentage (58%) was obtained with Patlcan cuttings treated with 1000 ppm IBA. Moreover, Singh, et al. [9], working with fig cv. Daulatabad revealed that IBA application at (500, 1000 and 1500 ppm) affected days to first sprouting and number of roots per cutting more than the other traits. Overall results showed that fig can be successfully propagated by cuttings with quick dip treatment of 1500 ppm IBA under mist chamber.

The beneficial effect of IBA, NAA and their combinations on rooting ability and some chemical constituents of several trees were reported by several workers such as Wahab, et al. [13] on gauava, Morsi, et al. [14] on fig, Hussein, et al. [15] on olive, Yusnita, et al. [16] on apple, Ayaz, et al. [17] on olive trees.

Accordingly, the present work was planned to study the effect of wounding and some growth regulators (IBA and NAA) at different concentrations on root production of fig cuttings of White Adriatic classified as hard to root variety.

Materials and Methods

The present study was carried out in the two successive seasons of 2006 and 2007 at the Experimental farm, Faculty of Agriculture, Fayoum Univ. at Demo, Fayoum, Egypt. Stem cuttings of fig (Ficus carica L.) cv. “White Adriatic” (14 years old) were used for propagation trials under greenhouse conditions. The stem cuttings of “White Adriatic” fig were prepared from hardwood cuttings (adult), taken from secondary branches on the fig trees grown in the Experimental farm of Faculty of Agriculture, Fayoum Univ. These trees were uniform as possible and received normally agricultural practices. The hardwood cuttings were prepared on February, 20th, 2006 and 2007 from one year old branches. Each treatment contained 30 cuttings in three replicates. The average length of each cutting was about 20 cm.

Wounding was carried out in the basal portions of the cutting as longitudinal cut with sharp knife for about 1.5 inch long directly below a node. These cuttings were sterilized with Rizolex 3gm /L. as fungicide for about 5 minutes and then were left for 30 minutes to dry. The basal portions were dipped in different concentrations of each growth regulators for quick dipping. Ethyl alcohol 50% was used as solvent for IBA and NAA. Cuttings were designed to study the effects of some treatments on root ability of stem cuttings of “White Adriatic” fig. The different treatments are summarized in Table 1.

Cuttings were prepared February on 20th, 2006 and 2007 and were stored in fine sand for a month to increase their root ability, then, they were treated with different treatments and then cultured March on 20th in media composed of peat- moss and sand (1:1v/v) in plastic boxes under greenhouse conditions. The experimental design used was complete randomized design. Each treatment contained 30 cuttings. The results were recorded after 30, 60 and 90 days from culturing.

Discussion

It is clear from the results of the present study that, rooting of fig Varity “White Adriatic” stem cuttings may be promoted by wounding the base of the cutting. Moreover, dipping bases the cuttings in different concentrations of any of growth regulators (indole butyric acid or naphthalene acetic acid) at different rates had a positive effect on rooting percentage of these cuttings. The beneficial effect of wounding and growth regulators on rooting percentage and growth characters (stem fresh weight; stem dry weight; stem length; stem diameter; leaves fresh weight/cutting; leaves dry weight/cutting; number of leaves /cutting; root length/ cutting; roots fresh weight/cutting) and roots dry weight/ cutting as well as chemical constituents of leaves (total carbohydrates, total sugars, reducing sugars, total free amino acids, total indoles, total soluble phenols, conjugated phenols, free phenols, nitrogen, phosphorus and potassium) may be attributed to that wounding plant cells near the base of the cutting stimulates plant cell division and the production of root primordia. This is due to a natural accumulation of hormones and carbohydrates in the wounded cells and to an increase in respiration rate [24]. In addition, the reduction in free phenols contrasted with the increase in total indoles, i.e. endogenous promoters increased and consequently endogenous inhibitors decreased in the leaves leading to an increase in cutting growth parameters such as stem length and leaves number/cutting as shown in Table 3. In this respect, Tognoni, et al. [25]. Moreover, Fadl MS [26] confirmed this idea and reported that easy-to-root cuttings produce one or more materials, depending upon their degree of physiological activity, which move to basal part of cutting and stimulate meristematic activity in this region causing root formation. The increase in stimulate meristematic activity in this region causing root formation. The increase in percentage of rooted cuttings may be due to the role of auxins in the cell division and initiation of root primodia. In this respect, Robbins, et al. [27] added that the presence of auxins, activates the cell division, directly by initiation of root primodia or indirectly by their involvement in overall metabolism. Also, Erikson and Mohamed [28] reported that, IBA increased rooting in treated cuttings by stimulating invitation of cambial activity, root vitals and root primordial. On the others hand, Issel and Chalmers, [29] showed that lower auxin concentration treatments (2500 ppm) can be more effective in adventitious root formation than higher concentrations (5000 ppm). The increase in rooting percentage leaves fresh and dry weight/ cutting and root fresh and dry weight/cutting may be due to the increase in carbohydrates, auxins and total amino acids in leaves and stem. In this respect, Reuveni and Ravin [30] reported that, rooting of cuttings was associated with such factors, as carbohydrates, auxins, vitamins and nitrogen compounds. The energy for such activity was derived from carbohydrates, and the oxogenous supply of auxins caused the mobilization of carbohydrates and accumulated near the base of cuttings where certain cells become meristemstic and initiate the roots [31].

Finally, from the present results, it could be concluded that the application of wounding as well as indole butyric acid (IBA) and naphthalene acetic acid (NAA) at different rates had a positive effect on rooting percentage of fig stem cuttings and consequently produced better growth seedlings. In this concern, it could be recommended to use wounding plus IBA at 4000 ppm or NAA at 1000 ppm alone or in combination to obtain best results.