Journal APS Oct 2017

W alnut

221

(1:1:1 respectively) and moved to the nursery conditions (open field and greenhouse with 50% shade) immediately.  The whip-tongue method was used and the graft area was tied with plastic tape and scions were also wrapped completely with parafilm. White water-based paint was applied on top of the plant. Temperature and relative humidity were recorded for four weeks following grafting with a data logger every 30 minutes (KIMO Digital Data Logger KT-100). To determine the grafting success, the sprouting ratio (%) of scion buds was recorded on 15 June.  The study was designed as a randomized complete block with four replications on each date. Each replication had 15 grafted plants. For each year, the effect of two locations (outdoor conditions and 50 % shaded greenhouse) and four grafting dates (15 March, 5 April, 25 April and 15 May) on grafting success were determined. The growth stage of rootstock seedlings on the grafting dates is presented in Table 3. A total of 480 rootstock seedlings were grafted per year. Data were analyzed with Levene’s test and Shapiro Wilk test to test the assumptions of variance homogeneity and normal distributed residuals. Each year data were

Dehgan et al, 2010; Soleimani et al., 2010). However, knowledge about relationships between different factors such as temperature and relative humidity and graft success of walnut are limited for outdoor conditions (Karadeniz, 2005; Mir and Kumar, 2011; Ahmed et al., 2012).  This study was conducted to determine the effects of environmental factors (represented by grafting time) and growth stage of rootstocks on graft success under outdoor and shaded greenhouse conditions. Materials and Methods  The experiment was conducted during 2012 and 2013 at the Black Sea Agricultural Research Institute, Samsun, Turkey (41º 13’ 48,67’’ N 36º 29’ 55,58’’ E; 7m above sea level). One-year-old seedlings of Juglans regia with uniform thickness (2.5±1 cm in diameter) were selected as rootstock and ‘Chandler’ cultivar was used as the scion. Scion wood (2.5±1 cm in diameter) was obtained in Feb. and stored at 4°C until grafting date. Rootstock seedlings were obtained in Jan. Roots were pruned slightly before planting to prevent sap leaking (bleeding) and were planted in pots (25 x 18 cm) containing a peat+perlite+soil mixture

Table.3 Mean temperature, relative humidity and rootstock shoot length for two years at the time of grafting. 2012 2013 Mean Temperature ( o C) Relative Humidity (%) Growth of Rootstock (cm) Mean Temperature ( o C) Relative Humidity (%) Growth of Rootstock (cm) Table 3. ˆ Mean temperature, relative humidity and rootstock shoot length for two years at the time of grafting.

15 March 5 April 25 April 15 May 15 March 5 April 25 April 15 May

15.5 19.2 20.8 23.5 13.7 16.7 19.5 9.8

70.2 64.7 48.4 52.4 67.4 73.3 78.5 76.3

0 2

16 17

78

2

83.6 78.2 73.4 70.7 77.8 71.6 69.8

17.9 27.9 39.3

50% Shaded Greenhouse

20.9 38.7

20.2 22.3 11.4 13.1 17.8 19.8

0 2

0

9.9

Open Field

11.2 24.3

20.3 24.9