Researches on the rootstock potentiality of chestnut types (Castanea sativa Mill.) grown in Marmara Region

Abstract

This research was conducted, with the aim to select the chestnut types which have superior quality with respect to their emergency rate, seedling growth and tolerance to drought. Fruit samples were collected from various parts of the Marmara Region, in different years. In total 56 types and / or cultivars were studied. Germination rates of unstratified seeds of some types were generally low (5.0-37.5 %) with one exception (52.5 %). While seeds of some types could break their dormancy after one month of stratification, the others needed 2-4 months. Average emergency rates of the types or cultivars varied from 17.6% to 86.6%. Soil conditions drastically affected these rates. Values of seedling height and diameter were changed, by the types. Maximum diameter was 6-7 mm, and height was nearly 30 cm after a season's growth. The coefficient of variance (CV) of height and diameter, straight growth habit, were also different according to the types. Albino seedling rate reached to 22 % in one type. More or less differences in tolerance to drought were determined among the types tested. The first sign of damage from water loss, commenced at the level of 8.1-17.7 % soil water content, and the complete damage occurred at 6.1-11.4% soil-water level, depending on the type. Water loss, from per cm(2) of leaf area was negatively correlated with the total surface leaf area of the type. When all data taken are into consideration, the following types could be distinguished in the first step of the selection study. 52112, 52114, 51101, 51104, 51205, 76, 60.