313 Determination of the Effects of Different Row Spacings on Yield and Some Other Properties of Pea (Pisum sativum L.) Cultivars Sown in Spring and Autumn E. Pekşen, H. Bozoğlu, A. Pekşen and A. Gülümser Ondokuz Mayis University Faculty of Agriculture 55139 Samsun Turkey Keywords: cultivar, sowing time, row spacing, yield Abstract This study was conducted to determine the effects of different row spacings (20, 30 and 40 cm) on fresh seed yield and some other properties of pea (Pisum sativum L.) cultivars (Carina, Sprinter and Utrillo) sown in spring and autumn in Samsun conditions. The experiment was set in split-split plot design with three replications. Green pod and fresh seed yield, pod/plant, pod length, seed/pod, unfilled seed/pod, fresh seed weight/fresh pod weight, fresh seed ratio remained above 9.5 mm sieve and under 7.5 mm sieve and protein content of seeds harvested at green mature stage were investigated. Utrillo (13.78 t/ha) and Sprinter (10.87 t/ha) were high yielded cultivars for green pod yield. The highest green pod yield was (14.49 t/ha) obtained from 20 cm row spacing. Autumn and spring sowings gave 13.49 and 7.64 t/ha green pod yield, respectively. For fresh seed yield, best cultivars were Utrillo (5.82 t/ha) and Sprinter (5.29 t/ha). 20 cm row spacing gave the highest fresh seed yield (6.67 t/ha). Fresh seed yield obtained from autumn sowing (6.64 t/ha) was higher than spring sowing (3.27 t/ha). According to the results of the study, Utrillo and Sprinter cultivars, 20 cm row spacing and autumn sowing may be recommended in Samsun conditions. INTRODUCTION Peas have been grown as an important source of animal feed and human food for many centuries. Several thousand varieties exist throughout the world. Peas can be classified into some categories such as field peas (providing forage for animal feed), market peas (from which pods are harvested for human consumption as a fresh vegetable), vining peas (for canning or freezing) and dried peas (partly for human consumption but mostly for animal feed) (Cousin, 1997). Cool growing season is necessary for successful pea production. High temperatures are more injurious to the crop than light frosts. Pea plants are resistant to light frosts except for blossom stage. Pea is the most productive in areas having regular rainfall regime. Pea is well adapted to the Black Sea region of Turkey and grown during both winter and spring growing seasons (Gulumser et al., 1994). However, late sowing (Shuckla and Kohli, 1992) and high temperatures in early spring can cause early flowering in pea plants. Thus, green pod and fresh seed yield decrease depending on reduction in the number of pods per plant. The objective of this study was to determine the effects of different row spacings on fresh seed yield and some other properties of pea cultivars sown in autumn and spring in Samsun conditions. Proc. 2nd Balkan Symp. on Veg. & Potatoes Eds. G. Paroussi et al. Acta Hort. 579, ISHS 2002