The effects of sour orange, carrizo and troyer citrange rootstocks on carbohydrates, plant nutritions in leaves and to fruit yield and quality of important citrus species and varieties grown in Antalya conditions

ABSTRACT THE EFFECTS OF SOUR ORANGE, CARRIZO AND TROYER CITRANGE ROOTSTOCKS ON CARBOHYDRATES, PLANT NUTRITIONS IN LEAVES AND TO FRUIT YIELD AND QUALITY OF IMPORTANT CITRUS SPECIES AND VARD2THCS GROWN IN ANTALYA CONDITIONS EBRU CUCU-ACDXALEV Ph.D. Thesis in Horticultural Sciences Adviser: Prof. Dr. Mustafa PEKMEZCİ December 2004, 193 pages In this study the following varieties have been investigated: Due to its early characteristic the Interdonato lemon; due to their high quality and high market demand the Clemantine mandarin and Washington Navel orange; due to its recent increasing market demand the Marsh Seedless grapefruit. The followings have been chosen as rootstocks: Sour orange, which is used widespread in our region, and Carrizo and Troyer citrange which were turned out as hopeful in recent studies. By investigating the growing of trees on the rootstock varieties, yield, fruit quality, chlorophyll contents, carbohydrate and plant nutrition contents, the best rootstock X scion combination has been determined. The trees, which are planted by 7 x 7 m in distance at Research and Experimental area at Serik-Kayaburnu in 1983, belonging to Batı Akdeniz Agricultural Research Institute, have been used as experiment materials. The laboratory studies have been carried out at Akdeniz University Agriculture Faculty Central Laboratory, Pomology Laboratory of Horticulture Department and at Soil and Plant Analysis Laboratory of Batı Akdeniz Agricultural Research Institute. As a result of our findings, lemon on the sour orange rootstock and other species on the Carrizo citrange rootstock have been determined as the best result with regard to yield and quality. As far as carbohydrate content of the investigated varieties concerned, the citrange rootstocks had the highest values. When we look at the seasonal changes, with regard to carbohydrate, chlorophyll and plant nutrition elements, we observed a similar seasonal change on the trees on Carrizo, Troyer citrange and sour orange. It has 111been determined that the carbohydrates, which are total carbohydrates, starch and carbohydrate/nitrogen ratio increased from spring until summer, decreased until autumn and increased again until winter; total sugar, reducing sugar and sukroz contents decreased from spring until autumn and increased until winter. It has been found out that the seasonal changes of plant nutrition elements, which are nitrogen (N), phosphorus (P) and potassium (K) increased from spring until summer, decreased until next spring; calcium (Ca), sodium (Na), iron (Fe) and manganese (Mn) concentrations increased from spring until winter, decreased until next spring; magnesium (Mg) increased from spring until autumn, decreased until next spring; zinc (Zn) decreased from spring until next spring and then increased until summer; copper (Cu) decreased from spring until autumn, increased until winter and then decreased until spring. The utilization levels of soil nutrition elements by different rootstocks varied. On Washington Navel, the sour orange rootstock in terms of Fe and Cu, the citrange rootstocks in terms of other nutrition elements, and on Clemantin mandarin generally the citrange rootstocks were more successful. It has been also determined that, on Interdonato lemon with regard to N, Na and Cu the sour orange, with regard to K, Ca and Fe the citrange rootstocks; on Marsh Seedless grapefruit with regard to K and Zn the sour orange, with regard to Mg, Na, Fe, Cu the Troyer citrange were more successful. As far as chlorophyll concerned, all varieties showed an increase from spring until winter and then an increase until next spring. As a result of our study, when we consider all of the factors in our regional conditions, for Washington Navel orange, Clemantine mandarin and Marsh Seedless grapefruit the Carrizo citrange rootstock; and for Interdonato lemon the sour orange rootstock have given the best results. KEY WORDS: Rootstock, variety, species, rootstock variety combination, tree growth, carbohydrate, plant nutrition element, chlorophyll, yield, quality. COMMITTEE: Prof. Dr. Mustafa PEKMEZCİ (Adviser) Prof. Dr. Turgut YEŞİLO?LU Prof. Dr. Lami KAYNAK Assoc. Prof. Dr. Mustafa ERKAN Assistant. Prof. Dr. Hamide GÜBBÜK IV