Morphological and Physiological Responses of Some Olive Cultivars Seedlingto Different Calcium Carbonate Levels and Drought in Soil.

Abstract

The Morphological and physiological responses of 6 olive cultivars seedlings namely; "Agezee", "Koroneiki", "Picual", "Nebal", "Manzanillo" and "Coratina" to three levels of calcium carbonate in soil (9.4%, 22% and 38.1% CaCO 3 ) and two irrigation levels which were 60% and 30% available water "A.W" were studied during two successive seasons, 2012 and 2013.The present study was achieved on one-year old seedlings grown in black plastic bags under saran green house conditions at the experimental farm of the Fac. of Agric. at Demo, Fayoum, Egypt.A negative relationship was found between CaCO 3 % in soil and/or deficit irrigation on growth Parameters of seedlings (plant height, leaf area, total shoot length/plant, dry weight/plant, root length density), total chlorophyll (mg/g fresh weight) and total carbohydrate %.There were great differences among cultivars in their response to CaCO 3 % in soil and drought. The cvs. that were most tolerant are "Nebal" followed by "Agezee" but "Coratina", "Koroneiki" and "Manzanillo" were most susceptible; while "Picual" was intermediate tolerant. INTRODUCTION:Olive is one of the most important fruit crops cultivated in the Mediterranean area and of increasing interest world-wide. This species has long been cultivated in marginal lands (Connor andFereres, 2005 andTherios, 2009). Nowadays, fruit crop species are more and more influenced by various kinds of environmental stress. Drought and high lime levels of the soil are the most important kinds of abiotic stress (koyroetal.2012).Calcareous soils occupy approximately 30% of the Earth's total land area. In Egypt, the calcareous soils constitute about 25 -30% of the total area according to Ministry of Agriculture estimation(2012).This area is one of the most promising areas for horizontal agriculture expansion in Egypt Calcareous soil significantly reduced plant height of "Chemlali" olive although trunk circumference was increment than those grown in clay soil (Rokba, 1985). Alcantara et al.(2003) evaluated "Arbequina", "Cornezueio de jaen", "Galega", "Leccino", "Lechindesevilla", "Manzanilla de sevilla", "Nevadillo negro" and "Pajarero" olive varieties grown in pots with high calcareous soil for their tolerance to lime induced chlorosis. They reported that there were