In this study, interior grafts of varieties with different development characteristics (Mondial, Gala, Braeburn and Red Chief) were applied on different rootstocks (M9 and MM106) and opportunities to grow saplings in greenhouses (high plastic tunnel) are sought for transition zones. In this study, the differences between outer fields and greenhouses in terms of graft success rates, sapling lengths and length of shoots, the numbers of lateral and 1^st class sapling rates were assessed.

The saplings were planted in experiment places in open and greenhouse and necessary cultural processes are applied. Among this procedure, irrigation was done with drip irrigation method and the fertilization program was applied with water whereas fertilization method according to analysis results from Eğirdir agricultural analysis laboratory (Table 1).

Meteorological data during the experiment period in outer environment and greenhouse where the research was started and ended are given in Table 2 as mean monthly temperature, the lowest and highest monthly temperature.

When the temperature differences between green-house and outer environment during the experiment period was examined, it was seen that the total daily average temperature in greenhouse was 1193.7°C more than the outside in the period between the plantation of materials to the parcels. When Table 2 was examined, daily average temperature of the inner environment was 4 to 6°C higher than the outer environment during the period from April to August when most of the grafting and sapling development occurs.

              Table 1.  The amount of fertilizer given to parcels experiment (g/saplings).

                   Table 2. Greenhouse environment and the monthly average values of ambient temperature.

Phenological findings

In Table 3, phenological observations were given. Differences were determined between varieties and environments in revival and blossoming dates. The first budburst (April 8) was in Mondial Gala variety grafted on M9 and MM106 rootstocks in greenhouse and the last budburst was outside in Braeburn and Red Chief (April 12) grafted on M9 and MM106. The first blossoming of the buds was in greenhouse in Mondial Gala (April 16) grafted on M9 and MM106 rootstock, the last vegetative bud blossoming was in Braeburn variety (April 23) grafted on M9 and MM106 rootstock. The first defoliation was outside in Mondial Gala (November 5) grafted on M9 and MM106 rootstock and the last defoliation was in greenhouse in Braeburn (November 17) grafted on M9 and MM106 rootstock (Table 3).

After the plantation of the experiment material during the first month, the total greenhouse temperature was 132.1°C and daily average was 4.4°C higher than outside. The differences between varieties stem from different cooling needs of varieties. In their study, Özongun et al. (2004) determined similar differences in phenological observations of varieties. Jonkers (1980) reported that defloration quickens at 9 to 13°C in apple and pear trees grown in outer environment and controlled temperature conditions. When mean temperatures in Tables 2 and 3 were examined, it is seen that the temperature which was 13.11°C in October outside dropped to 5.43°C in November and that the temperature in the greenhouse was 17.9°C and dropped to 8°C in November. According to these results, defloration is parallel to the decrease inner and outside temperatures.

                                            Table 3. Phenological observations.

Morphological results

When experiment criteria are assessed all together, the highest rate of grafting was in Braeburn in greenhouse with 93%, which was grafted on M9 rootstock with chip budding and bench grafting techniques and the difference was found to be statistically significant (P < 0.01). The lowest grafting rate was 40% in Red Chief, which was grafted on MM106 rootstock outside (Table 4). High rate of grafting in greenhouse is an expected result. As a matter of fact, many studies carried out on various fruit varieties reported similar results. Many researchers noted that temperature is one of the most important factors in graft success (Özongun et al., 2006; Yilmaz and Akça, 2003; Polat et al., 1998; Polat and Kaşka, 1991, 1992, 1996; Gadalina, 1995) and it is similar to our results, as well.

When multi interactions are examined, the length of sapling ( 181.60 cm), sapling diameter (12.07), sapling shoot length (163.49 cm) and the rate of 1^st class sapling (100%) was in Mondial Gala in MM106 grained bud graft in greenhouse environment and statistically significant ( p < 0.01) and in Braeburn variety-which was grafted on MM106 rootstock with grained bud graft- the sapling shoot diameter was 12.27 mm and the number of lateral was 4.43 and was statistically significant (P < 0.01). All other multi interactions and applications were found to be insignificant (Table 4).

When the lengths of saplings were assessed, it is seen that Mondial Gala is the strongest developing variety in terms of the sapling length development, which was followed by Braeburn and Red Chief (Table 4). When Table 4 was examined, it is seen that even the developmental characteristic of the strongest variety (Mondial Gala) grown outside has shorter sapling than the weakest variety (Red Chief) in greenhouse. The reason for this is that the vegetation period in greenhouse is longer and total temperature is higher compared with outside environment. In this study, depending on the variety of sapling, vegetation period varies between 215 and 225 days in greenhouse, while it ranges between 205 to 210 days outside. The average daily temperature in green-house was 4.7°C higher than the outside. Bağci et al. (2003) grafted golden delicious and starking delicious varieties of M9, MM26 and MM106 rootstocks and obtained 99.2 cm average sapling length in greenhouse and 64.6 cm sapling length outside. In this study, Gadalina (1995) determined developmental differences in regions with different climatic conditions and Yilmaz and Akça (2003), in their study with inside grafts on apple, reported that if they had planted the fruit saplings outside, the development of the plants would have been different because of vegetation and environmental conditions.

When the thicknesses of the different varieties of saplings in greenhouse and outside were examined in terms of shoot thickness, it was noted that the shoot diameter of Mondial Gala with its strong development characteristic and Braeburn variety with its mild development characteristic were in the same group and Red Chief variety with weak development characteristic had thinner shoots as expected (Table 5).

Yilmaz and Akça (2003) grafted Granny Smith on different apple rootstocks with different graft techniques. For M9 rootstock 107 cm shoot with bench graft, 90.21 cm shoot with chip graft, as for MM106 rootstock, 105.08 cm shoot length with bench graft and 127.17 cm shoot length with chip graft was obtained. Fere and Barden (1971) grafted Golden Delicious variety on M7, MM106 and apple seedling and reported that shoots on seedling and MM106 were developed better than dwarf rootstocks.

 In this study, no difference was found between grafting methods in terms of shoot and sapling development. Rajesh and Ananda (2002) used spur and redspur as varieties and wild apple seedling as rootstock and bench grafting, English grafting and grained grafting as grafting techniques and reported that chip grafting  had the best development linear and radial development.

When two way interactions were examined, it was found that the effect of Rootstock and Variety interaction was significant (P < 0.05) in terms of shoot diameter but not significant for other features. The highest shoot diameter was in Mondial Gala variety grafted on MM106 rootstock. The environment and variety interaction was found to be leading to statistically significant difference in Mondial Gala variety in greenhouse environment, in which the sapling length was 167.87 cm, the length of the shoot was 144.74 cm and the 1^st class sapling rate was 98.23% compared with other environment and variety combinations (p < 0.01). In terms of grafting technique and variety interaction, the number (3.03) of side branch was found to be statistically significant in Braeburn variety to which chip budding grafting was applied (p < 0.01). In terms of environment and rootstock interaction, the rate (96.36%) of 1^st class grafting was found to be statistically significant (p < 0.01). In terms of grafting technique and rootstock interaction, the sapling length was (128.14 cm) (P < 0.01), the shoot diameter was (9.77 mm) (p < 0.05), the shoot length was (102.49 cm) and the side branch number (1.84) (P < 0.01) was found to be statistically significant in MM106 rootstock. When the interactions were examined again in terms of environ-ment and grafting technique, the rate of grafting success was found to be statistically significant in outer environ-ment with bench grafting (P < 0.01). All other interactions and applications were found to be statistically insignificant (Table 5).

When the factors in the trail were examined one by one, there found to be statistical differences in terms of rootstock, varieties, growing environment and grafting technique. When the rootstocks were examined, the rate was found to be the highest in M9 rootstock (79.00%) (P < 0.01), the longest sapling (126.76 mm), the largest shoot diameter (9.55 mm), the longest shoot (99.93 mm) (p < 0.01). The highest number of side branch (1.68) (P < 0.05) and the highest rate of 1^st class sapling (88.13%) (P < 0.01) was in MM106 rootstock.

When the rate of grafting success in outer environment and greenhouse was examined, it was seen that the rate of success was 82% in greenhouse and 69% in outer environment (Table 6). The daily temperature means in April was 16.6°C in greenhouse and 12.2°C outside. When the grafting success was examined in terms of grafting technique, with bench grafting technique, the rate was 82% in greenhouse and outside, the rate was 73% with chip budding grafting technique in greenhouse and in outer environment it was as low as 56% (Table 6).

In their study, Bağci et al. (2003) reported that the rate of grafting was 86 to 89% in Golden Delicious and Starking Delicious varieties applied on M9 and MM106 rootstocks with chip budding grafting technique in green-house, which was higher compared with outer environment. Yilmaz and Akça (2003) found that graft life rate was 30 to 35% in Granny Smith varieties applied to different apple rootstocks with chip budding grafting and bench grafting technique in greenhouse. In their study on Starking Delicious variety in outer environment, Özongun et al. (2006) obtained 80% success with bench grafting technique and 33% with chip budding grafting technique. Howard and Quinlan (1984) reported similar results with bench grafting, English, bench grafting and chip budding grafting methods. Yilmaz and Akça (2003) reported that the graft junction surface was larger in bench grafting method as the scar surface in bench grafting method was larger compared with chip budding graft and this had a positive effect on graft success. 

When the varieties was examined as it can be seen in Table 6 in Mondial Gala variety, the rate of grating success was (79.00%) ( P < 0.05), the sapling length (129.97 cm), the shoot thickness (9.29 mm), the shoot length (104.73 cm) and 1^st class sapling rate (88.11% ), were significantly higher compared with other varieties (P < 0.01), but the highest number (2.76) of side branch was determined in Braeburn variety (P < 0.01).

When sapling shoot lengths were examined according to the varieties, it was found that Mondial Gala variety-gro wn in outer environment and in greenhouse-was the stron gest variety in terms of sapling shoot length, which was followed by Braeburn and Red Chief varieties (Table 6).

When the effect of rootstocks on the sapling shoot thickness was examined, it was found out that the sap-lings on MM106 rootstock developed better than the saplings on M9 rootstock (Table 6). In their study, Bağci et al. (2003) had similar results. They found out that shoot thickness of saplings grafted on MM106 rootstock was larger than those of the shoots grafted on M9 rootstock. Yilmaz and Akça (2003) reported that there was no significant difference between the shoot thick-nesses of shoots grafted on M9 and MM106 rootstock.

The rate of graft success (82.00%), the sapling length (146.00 cm), the diameter of shoot (10.71 mm), the length of shoot and the rate of 1^st class saplings (94.35%) in greenhouse were found to be statistically significant compared with open environment results (P < 0.01).

When grafting techniques were compared and the success rate of bench graft (82.00%) was found to be higher than chip budding grafting technique (P < 0.01), but the other results were not found to be statistically significant (Table 6).

Table 4. Evaluation of all factors in the experiment.

*P < 0.05. There is no difference between the groups with the same letter;** P < 0.01, there is no difference between the groups with the same letter. ( ); standard error.

Table 5. Retention rates of the factors used in the vaccine trial, sapling length, shoot diameter, shoot length, lateral branch number and first class nursery in terms of interactions taken place between each couple.

*P < 0.05, There is no difference between the groups with the same letter; ** P < 0.01; there is no difference between the groups with the same letter. ( ); standard error.

Sapling quality

In the assessment of saplings grown according to sapling standards (clonal dwarf and semi-dwarf apple rootstocks) determined in the USA in 2004, the highest sapling standard was in the saplings of Mondial Gala variety which was grown in greenhouse and grafted on MM106 rootstock with chip graft technique. In terms of these standards, the lowest value was in the saplings of Red Chief variety grafted on M9 rootstock with chip graft technique (Table 4).

In terms of compliance with the standards, environment and variety interaction and environment and rootstock interaction were found to be significant. In terms of environment and variety interaction, while Mondial Gala variety (98%) in greenhouse obtained the highest rate, the lowest rate (44%) was in Red Chief variety grown in outer environment (Table 5).

When the factors in the trail were assessed within their own groups, while significant differences were found in terms of rootstocks, varieties and environments, there was no significant difference in terms of grafting technique, except for grafting success (P < 0.01). When rootstocks were examined, while the rate of standard saplings in MM106 rootstock was 88%, the rate was 73% in M9 rootstock. When varieties were examined, the rate of standard sapling in Mondial Gala was 88%, in Braeburn, it was 86% and in Red Chief it was 67% (Table 6).

When assessed according to sapling scale, only unbranched sapling was grown in outer environment (29.10%); however, in greenhouse environment, unbranched sapling was (57.30%), a few branched sapling (9.40%), branched sapling (13.50%) and extra branched sapling (11.0%). In total, 91.20% of the saplings grown in the greenhouse were in vendible sapling class according to the prepared scale (Table 7).

A significant difference was found in terms of unbranched sapling features of varieties and rootstocks in outer environment (P < 0.01). In terms of varieties, the highest rate was in Mondial Gala variety (44.80%), which was followed by Braeburn (33.90%) and Red Chief varieties (8.5%). In terms of rootstocks, the rate of unbranched sapling in MM106 was found to be significantly higher (P < 0.01) (43.50%) compared with M9 rootstock (17.60%) (Table 7).

According to fruit sapling scale, some applications in the greenhouse were found to be statistically significant (P < 0.01 and P < 0.05). While Red Chief variety (82.50%) had higher rate of unbranched sapling compared with other varieties, in total (a few branched sapling, branched sapling and extra branched sapling) Mondial Gala (98.3%) and Braeburn (91.6%) varieties reached higher numbers in terms of growing saplings. In terms of having extra branched sapling, Braeburn variety had the highest rate (22.50%) (Table 7).

According to sapling standards (Anonymous, 2004b), there were found differences in terms of growing environments, varieties and rootstocks, in greenhouse environment (94.30%) there were higher numbers of saplings complying with standards compared with outer environment (66.7%) (Table 6). In their study, Bağci et al. (2003) found that the plant growth in greenhouse was better compared with outer environment. In terms of sapling standard, the highest rates were in Mondial Gala, Braeburn and Red Chief varieties, respectively (Table 6). Özongun et al. (2004) pointed out that Mondial Gala had strong growth character, Braeburn had semi-strong and Red Chief had weak growth character.

In terms of rootstocks, in MM106 rootstock standard, sapling rate (88.3%) was higher than that of M9 rootstock (72.8%), which is an expected result as the growth strength of MM106 rootstock was higher than that of M9 rootstock (Rom et al., 1987). In their studies, Ferre and Barden (1971), Bağci et al. (2003) and Yilmaz and Akça (2003) reported that different clonal apple rootstocks had different growth strength and that MM106 rootstock had better growth strength than M9 rootstock. The results are parallel to the results of our study.

Table 6. Evaluation of  the factors applied in the experiment.

*P < 0.05; There is no difference between the groups with the same letter; ** P < 0.01, there is no difference between the groups with the same letter. ( ), Standard error.

 Table 7.  The values obtained according to scala of clonal apple rootstocks (M9 and MM106) and fruit sampling.

*P < 0.05. There is no difference between the groups with the same letter; ** P < 0.01; there is no difference between the groups with the same letter. ( ), Standard error.