Özet: Aşılı fide, dünyanın birçok ülkesinde sebze yetiştiriciliğinde yaygın olarak kullanılmaya başlamıştır. Aşılı karpuz, kavun ve hıyar yetiştiriciliğinde; tuzluluk problemi olan arazilerde kestane kabağı ve bal kabaklarının, anaç olarak kullanımı önerilmektedir. Bu çalışmada, tuza tolerant olarak belirlenen ümitvar kestane kabağı ve bal kabağı anaçlarının hipokotil özellikleri ve hıyar ile aşı başarı oranları incelenmiştir. Gordion hıyar çeşidi, kalem olarak kullanılmıştır. Genotipler arasında en uzun hipokotil boyu G14 anacında 29.15 mm ve en kısa ise G40 anacında 15.15 mm olarak ölçülmüştür. Hipokotil kalınlığı, en fazla G40 (4.81 mm) genotipinde belirlenmiştir. Aşı başarı oranları, anaçlara göre %50-87 arasında değişim göstermiştir. Başarı oranı en yüksek olan anaç genotipler sırasıyla G31 bal kabağı anacı (%87) ve G15 türler arası melez anacı (%70) olarak belirlenmiştir. Aşılı hıyar fidelerinin, aşısız bitkilere göre daha fazla vejetatif büyüme gösterdiği saptanmıştır. Yapmış olduğumuz bu çalışma sonucunda, G31 ve G15 kabak anaç çeşit adaylarının tuza tolerant ilk yerli hıyar anaçları olma yönünde ümitvar oldukları bulunmuştur. Tuza tolerant olarak belirlenen bu anaçlar, önümüzdeki dönemde ticari aşılı hıyar fidesi üretiminde kullanılabilecektir. Abstract: Grafted seedlings recently are being used widely for vegetable grown in many countries of the world. Winter squash and pumpkins were recommended for use of rootstocks for the grafted watermelon, melon and cucumber growing in the saline soils. In this study, the promising salt tolerant winter squash and pumpkin rootstock lines were used and grafting compatibility, survival rates for grafted cucumber seedling was evaluated. Gordion cv. (cucumber) was used as a scion. In this study, hypocotyls traits and grafting success ratios were also determined. The longest hypocotyl (29.15 mm) was recorded in G14 rootstock while G40 had the shortest (15.15 mm). The highest hypocotyl diameter (4.81 mm) was determined in G40 genotype. Grafting success of these rootstocks were found between 50.0-87.0%. It was determined that the grafting success of G31 (87%) pumpkin genotypes, G15 (70%) interspecific genotypes with Gordion cucumber cultivar was the highest. The grafted cucumber genotypes gave the highest vegetative growth compared to ungrafted control seedlings. To conclude, G31 and G15 rootstock candidates were found to be the first local salt-tolerant rootstocks for cucumber breeding studies. These findings showed that selected promising salt tolerant rootstock genotypes will be used for commercial grafted cucumber seedling production in near future. Giriş Tuzluluk, toprakların verimliliğini olumsuz yönde etkileyen ve ürün verim potansiyelini sınırlandıran en önemli abiyotik stres faktörlerinden birisidir. Tuzluluk zararı, bitkilerin Na + iyonunu almalarıyla birlikte ortaya çıkmaya başlamakta ve bu zararın miktarı bitki tür ve çeşitlerine göre farklılık göstermektedir.

To determine how the use of a given rootstock can influence the functioning of the photosynthetic apparatus of the scion under salt stress, the growth, gas exchange, photosystem II (PSII) efficiency, xanthophyll cycle, and chloroplast ultrastructure of nongrafted, self-grafted, and pumpkin-grafted (hereafter referred to as rootstock-grafted) cucumber (Cucumis sativus L.) plants were investigated at day 15 after being treated with 90 mM NaCl. The reductions in plant growth of the rootstock-grafted plants were lower than those of the nongrafted and self-grafted plants under 90 mM NaCl. The net photosynthetic rate, stomatal conductance, maximal and effective quantum yield of PSII photochemistry, photochemical quenching coefficient, and effective quantum-use efficiency of PSII in the light-adapted state of the nongrafted and self-grafted plants were significantly decreased under 90 mM NaCl. However, these reductions were alleviated when the cucumber plants were grafted onto the pumpkin (Cucurbita moschata Duch.) rootstock. The intercellular CO 2 concentrations were significantly increased in the nongrafted and self-grafted plants under 90 mM NaCl, whereas it was decreased in the rootstock-grafted plants. Nonphotochemical quenching (NPQ) and the deepoxidation state of the xanthophyll cycle were significantly increased under 90 mM NaCl, particularly in the rootstockgrafted plants, suggesting the rootstock-grafted plants had higher potential to dissipate excess excitation energy and reduce the probability of photodamage to PSII. Under 90 mM NaCl, the number of grana was reduced, the thylakoids were swollen, and starch granules accumulated in all plants. However, the damage of chloroplast ultrastructure was alleviated in the rootstock-grafted plants. Taken together, the use of C. moschata rootstock alleviated salt stress in cucumber plants by delaying photoinhibition, probably due to a lower incidence of both stomatal and nonstomatal factors limiting photosynthesis.