PHYSIOLOGICAL AND HISTOLOGICAL STUDIES ON ALTERNATE BEARING OF OLIVES

PHYSIOLOGICAL AND HISTOLOGICAL STUDIES ON ALTERNATE BEARING OF OLIVES By TAHA FATHY AHMED MOHAMED EL-SHARONY B.Sc. Agric. Sci. (Pomology), Fac. Agric., Cairo Univ., 2002 M.Sc. Agric. Sci. (Pomology), Fac. Agric., Cairo Univ., 2007 THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY In Agricultural Sciences (Pomology) Department of Pomology Faculty of Agriculture Cairo University EGYPT 2012

APPROVAL SHEET PHYSIOLOGICAL AND HISTOLOGICAL STUDIES ON ALTERNATE BEARING OF OLIVES Ph.D. Thesis In Agric. Sci. (Pomology) By TAHA FATHY AHMED MOHAMED EL-SHARONY B.Sc. Agric. Sci. (Pomology), Fac. Agric., Cairo Univ., 2002 M.Sc. Agric. Sci. (Pomology), Fac. Agric., Cairo Univ., 2007 APPROVAL COMMITTEE Dr. ABD ELFATTAH SOLIMAN WALLY.. Head Research of Pomology, Hort. Res. Inst., Agric. Res. Center Dr. MOHAMED ABD EL-GAWAD SHAHEEN.... Professor of Pomology, Fac. Agric., Cairo University Dr. SAMIRA MANSOUR MOHAMED...... Professor of Pomology, Fac. Agric., Cairo University Dr. EL-SAID SADEK HEGAZI....... Professor of Pomology, Fac. Agric., Cairo University Date: / /2012

SUPERVISION SHEET PHYSIOLOGICAL AND HISTOLOGICAL STUDIES ON ALTERNATE BEARING OF OLIVES Ph.D. Thesis In Agric. Sci. (Pomology) By TAHA FATHY AHMED MOHAMED EL-SHARONY B.Sc. Agric. Sci. (Pomology), Fac. Agric., Cairo Univ., 2002 M.Sc. Agric. Sci. (Pomology), Fac. Agric., Cairo Univ., 2007 SUPERVISION COMMITTEE Dr. EL-SAID SADEK HEGAZI Professor of Pomology, Fac. Agric., Cairo University Dr. SAMIRA MANSOUR MOHAMED Professor of Pomology, Fac. Agric., Cairo University Dr. MOSTAFA RAMADAN EL-SONBATY Researcher Professor of Pomology, Horticultural Crops Technology Dept. - National Research Center

Name of Candidate: Taha Fathy Ahmed Mohamed El-Sharony Degree: Ph.D. Title of Thesis: Physiological and Histological Studies on Alternate Bearing of Olives. Supervisors: Dr. El-Said Sadek Hegazi Dr. Samira Mansour Mohamed Dr. Mostafa Ramadan El-Sonbaty Department: Pomology Approval: / / ABSTRACT The present study was carried out for three successive seasons 2008/2009, 2009/2010 and 2010/2011 on fifteen years old of olive trees cv. Picual, The study included two experiments: The first experiment: was to detect the degree of the tendency of some olive cultivars (Picual, Manzanillo, Toffahi, Aggizi Shami and Koroneiki) to alternate bearing. The second experiment: was an attempt to reduce the degree of alternate bearing to the olive cv. Picual through: spraying gibberellic acid (GA 3 ), spraying naphthalene acetic acid (NAA), fertilization by NPK over than the rates recommended by the Ministry of Agriculture and Lands Reclamation or spraying potassium nitrate (KNO 3 ). The results showed that, olive cv. Picual have the highest alternate bearing index while Toffahi cultivar gave the lowest alternate bearing index. Spray of GA 3 had a slight effect on increasing the buds content of indole acetic acid, increased the buds content of gebberllic acid and reduced the buds content of abscisic acid in comparison with control. Also, spray of GA 3 resulted in reduce the buds contents of cytokinines (Zeatin - Kinetin - benzyl adenine). Spraying olive trees cv. Picual befor on year with GA 3 at 75 ppm in first December led to the inhibition and slow the transition of buds to the floral state (buds thinning). As well as, spray the trees with GA 3 impact on reducing the density of flowering, fruit set, and yield and led to an increase in vegetative growth and as improvement in fruit characteristics and increase the oil percentage. Spraying olive trees in heavy crop year with NAA at 150 ppm after 30 days from full bloom led to improve the vegetative growth and reduced the yield and alternate bearing degree, also it had a positive effect on improving the fruit characteristics and oil content. Fertilizing olive trees with 50% over NPK recommended doses in heavy crop year had a positive effect on improving the flowering characteristics, fruit set, vegetative growth and increase yield in application year and the next year and reduce the degree of alternate bearing and improves fruit characteristics and oil content. Potassium nitrate sprays at 4% after final fruit set had an effect on the improvement of nutritional status, vegetative growth, yield and reduce the degree of alternate bearing, while Potassium nitrate sprays at 4% after pit hardening led to the improvement of fruit characteristics and oil content. Therefore, it could be recommended to use GA 3 at 75 ppm on first December for buds thinning or NAA spray at 150 ppm after 30 days from full bloom for fruit thinning or soil fertilization with 50% over NPK recommended doses or spray potassium nitrate at 4% after final fruit set and after pit hardening. Key words: Olive, Picual, alternate bearing, gibberellic acid (GA 3 ), naphthalene acetic acid (NAA), fertilization, potassium nitrate, hormones buds content, vegetative growth, folwering, fruit set, yield, fruit characteristics and oil content.

DEDICATION I dedicate this work to whom my heart felt thanks; to my father and my mother for the good deed and gratitude, as well as to my brothers, sister and my wife for all the support they lovely offered along the period of my post graduation and finally, to my beloved daughters Mai and Malak my beautiful life flowers.

ACKNOWLEDGEMENT I would like to express my deepest and greatest thanks to "Allah", the merciful and clement God who gave me the patience, power, knowledge, and helped me to carry out this work. I wish to express my sincere thanks, deepest gratitude and appreciation to Dr. E. S. HEGAZI Professor of Pomology, Faculty of Agriculture, Cairo University for his supervision, advices, continued assistance and guidance through the course of study and revision the manuscript of this thesis. Great thanks are also to Dr. S. M. MOHAMED, Professor of Pomology, Faculty of Agriculture, Cairo University for her supervision, kindly help and advices. Sincere thanks and deepest gratitude are also to Dr. M. R. EL-SONBATY, Professor of Pomology, National Research Center for suggesting the problem, supervision, and kind help encouragement. Sincere thanks to Dr. S. K. M. Abd El-Naby, Professor of Pomology, National Research Center for kindly help, advices and continued assistance. Appreciation is also extended to Dr. M. A. Bekheta Professor of Botany, National Research Center for kindly help encouragement.

LIST Of ABBREVIATIONS ABI: Alternate Bearing Index GA 3 : Gibberellic acid GAs: Gibberellins NAA: Naphthalene Acetic Acid NPK: Nitrogen, Phosphorus and Potassium KNO 3 : Potassium nitrate IAA: Indole Acetic Acid ABA: Abscisic acid Z: Zeatin K: Kinetin BA: Benzyl Adenine DFFB: Days from full bloom

CONTENTS Page INTRODUCTION... 1 REVIEW OF LITERATURE...... 5 1. Alternate bearing index of some olive cultivars... 5 2. Alternate bearing in relation to flower buds differentiation and phytohormones...... 7 3. Relation between alternate bearing and trees blooming...... 13 a. Effect of gibberellic acid (GA 3 )...... 14 b. Effect of fertilization... 18 4. Relation between alternate bearing and vegetative growth...... 21 a. Effect of gibberellic acid (GA 3 ).......... 23 b. Effect of naphthalene acetic acid (NAA).... 24 c. Effect of fertilization... 24 5. Alternate bearing in relation to leaves mineral contents.... 25 6. Relation between alternate bearing and yield... 30 a. Effect of gibberellic acid (GA 3 )...... 31 b. Effect of naphthalene acetic acid (NAA)..... 33 c. Effect of fertilization... 36 7. Relation between alternate bearing and fruit characteristics.... 38 a. Effect of gibberellic acid (GA 3 )...... 38 b. Effect of naphthalene acetic acid (NAA)..... 40 c. Effect of fertilization... 42 MATERIALS AND METHODS... 45 RESULTS AND DISCUSSION... 55 1. Alternate Bearing Index (ABI)... 55 2. Reducing the degree of alternate bearing to olive cv. Picual through four trails: a. Gibberellic acid (GA 3 ) application... 56 I

(1) Effect of spraying with GA 3 on the endogenous hormonal contents of olive buds...... 56 (a) Indole acetic acid (IAA)...... 56 (b) Gibberellic acid (GA3)......... 57 (c) Abscisic acid (ABA)...... 57 (d) Zeatin (Z)....... 62 (e) Kinten (K)...... 62 (f) Benzyl adenine (BA)...... 63 (2) Effect of spraying with GA 3 on flower bud differentiation...... 67 (3) Effect of spraying with GA 3 on flowering characteristics...... 73 (a)-flowering density... 73 (b) Inflorescence length (cm)... 73 (c) Number of total flowers per inflorescence... 73 (d) Number of perfect flowers per inflorescence... 76 (e) Number of male flowers per inflorescence... 76 (f) Sex ratio... 76 (4) Effect of spraying with GA 3 on fruit set... 77 (a) Initial fruit set... 77 (b) Final fruit set... 79 (5) Effect of spraying with GA 3 on vegetative growth characteristics...... 79 (a) Number of new shoots...... 79 (b) Number of leaves/shoot...... 80 (c) Leaf area (cm 2 )........ 80 (6) Effect of spraying with GA 3 on yield and alternate bearing index...... 82 (7) Effect of spraying with GA 3 on fruit characteristics...... 84 (a) Fruit length...... 84 (b) Fruit diameter...... 84 (c) Fruit shape index ratio (L/D)....... 87 (d) Fruit weight...... 87 II

(e) Flesh weight...... 87 (f) Seed weight... 87 (g) Flesh/fruit percentage... 88 (h) Seed/fruit percentage....... 88 (i) Flesh dry Weight (%)..... 88 (j) Flesh oil content (%)...... 92 b. Naphthalene Acetic Acid (NAA) application... 94 (1) Effect of spraying with NAA on vegetative growth characteristics...... 94 (a) Number of new shoots...... 94 (b) Number of leaves/shoot...... 94 (c) Leaf area (cm 2 )...... 94 (2) Effect of spraying with NAA on yield and alternate bearing index...... 96 (3) Effect of spraying with NAA on fruit characteristics...... 99 (a) Fruit length...... 99 (b) Fruit diameter...... 99 (c) Fruit shape index ratio (L/D)...... 100 (d) Fruit weight...... 100 (e) Flesh weight...... 100 (f) Seed weight...... 101 (g) Flesh/fruit ratio..... 101 (h) Seed/fruit ratio...... 105 (i) Flesh dry Weight... 105 (j) Flesh oil content.... 105 c. NPK Fertilization application... 107 (1) Effect of fertilization with NPK on flowering characteristics...... 107 (a)-flowering density... 107 (b) Inflorescence length (cm)... 107 (c) Number of total flowers per inflorescence... 107 (d) Number of perfect flowers per inflorescence... 107 III

(e) Number of male flowers per inflorescence... 108 (f) Sex ratio... 108 (2) Effect of fertilization with NPK on fruit set... 110 (a) Initial fruit set... 110 (b) Final fruit set... 110 (3) Effect of fertilization with NPK on vegetative growth characteristics...... 111 (a) Number of new shoots...... 111 (b) Number of leaves/shoot...... 111 (c) Leaf area (cm 2 )...... 111 (4) Effect of fertilization with NPK on leaves mineral contents...... 113 (5) Effect of fertilization with NPK on yield and alternate bearing behavior...... 114 (6) Effect of fertilization with NPK on fruit characteristics...... 116 (a) Fruit length...... 116 (b) Fruit diameter...... 116 (c) Fruit shape index ratio (L/D)...... 116 (d) Fruit weight...... 115 (e) Flesh weight...... 117 (f) Seed weight...... 117 (g) Flesh/fruit ratio.... 117 (h) Seed/fruit ratio......... 117 (i) Flesh dry Weight... 118 (j) Flesh oil content....... 118 d. Potassium nitrate (KNO 3 ) application.. 122 (1).-Effect of spraying with KNO 3 on vegetative characteristics.. 122 (a) Number of new shoots......... 122 (b) Number of leaves/shoot......... 122 (c) Leaf area (cm 2 )...... 122 (2). Effect of spraying with KNO 3 on leaves contents of NPK...... 124 IV

(3).-Effect of spraying with KNO 3 on yield and alternate bearing index... 125 (4).-Effect of spraying with KNO 3 on fruit characteristics.. 126 (a) Fruit length...... 126 (b) Fruit diameter...... 126 (c) Fruit shape index ratio (L/D)...... 126 (d) Fruit weight...... 129 (e) Flesh weight...... 129 (f) Seed weight...... 129 (g) Flesh/fruit ratio.... 129 (h) Seed/fruit ratio..... 130 (i) Flesh dry Weight... 130 (j) Flesh oil content... 130 SUMMARY... 133 REFERENCES..... 153 ARABIC SUMMARY V

LIST OF TABLES No. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Title World cultivated area with Olive and its productivity of fruit and oil during the period from 2000 to 2010... Area planted with Olive and its productivity in Egypt during the period from 2000 to 2009 Some physical and chemical analysis of the experimental soil used in the present study.... Average maximum, minimum & day temperature and relative humidity/month from December 2008 to November 2011... Alternate Bearing Index (ABI) of olive cvs. Picual, Manzanillo, Toffahi, Aggizi Shami and Koroneiki under El-Sadat region condition during the period from 2009 to 2011...... Effect of gibberellic acid spraying on some flowering characteristics of olive trees cv. Picual from 2009 to 2011 seasons. Effect of gibberellic acid spraying on some flowering characteristics of olive trees cv. Picual from 2009 to 2011 seasons. Effect of gibberellic acid spraying on fruit set of olive trees cv. Picual from 2009 to 2011 seasons... Effect of gibberellic acid spraying on some vegetative characteristics of olive cv. Picual from 2009 to 2011 seasons. Effect of gibberellic acid spraying on yield and alternate bearing index of olive trees cv. Picual from 2009 to 2011 seasons VI Page 4 4 53 54 55 74 75 78 81 85

11. 12. 13. 14. 15. 16. 17. 18. 19. 20. Effect of gibberellic acid spraying on some fruit characteristics of olive cv. Picual from 2009 to 2011 seasons..... Effect of gibberellic acid spraying on some fruit characteristics of olive cv. Picual from 2009 to 2011 seasons..... Effect of gibberellic acid spraying on flesh and seed weight percentage of olive cv. Picual from 2009 to 2011 seasons........ Effect of gibberellic acid spraying on flesh dry weight and flesh oil content percentage of olive cv. Picual from 2009 to 2011 seasons.... Effect of naphthalene acetic acid spraying on some vegetative characteristics of olive cv. Picual from 2009 to 2011 seasons... Effect of naphthalene acetic acid spraying on yield of olive trees cv. Picual from 2009 to 2011 seasons... Effect of naphthalene acetic acid spraying on fruit dimensions and fruit shape index of olive cv. Picual from 2009 to 2011 seasons... Effect of naphthalene acetic acid spraying on weights of fruit, flesh and seed of olive cv. Picual from 2009 to 2011 seasons... Effect of naphthalene acetic acid spraying on flesh and seed weights percentage of olive cv. Picual from 2009 to 2011 seasons... Effect of naphthalene acetic acid spraying on flesh dry weight and flesh oil content percentage of olive cv. Picual from 2009 to 2011 seasons... 86 89 90 91 95 97 98 102 103 104 VII

21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. Effect of NPK as soil fertilization on some flowering characteristics of olive trees cv. Picual from 200 to 2011 seasons. Effect of NPK as soil on some flowering characteristics of olive trees cv. Picual from 2009 to 2011 seasons. Effect of NPK as soil fertilization on fruit set of olive trees cv. Picual from 2009 to 2011 seasons... Effect of NPK as soil fertilization on some vegetative characteristics of olive cv. Picual from 2009 to 2011 seasons... Effect of NPK as soil fertilization on NPK contents of olive leaves cv. Picual during 2009 and 2010 seasons. Effect of NPK as soil fertilization on yield and alternate bearing index of olive cv. Picual from 2009 to 2011 seasons..... Effect of NPK as soil fertilization on fruit dimensions and fruit shape index of olive cv. Picual from 2009 to 2011 seasons...... Effect of NPK as soil fertilization on weights of fruit, flesh and seed of olive cv. Picual from 2009 to 2011 seasons...... Effect of NPK as soil fertilization on flesh and seed weight percentage of olive cv. Picual during 2009 and 2010 seasons..... Effect of NPK as soil fertilization on flesh dry weight and oil content percentage of olive cv. Picual during 2009 and 2010 seasons... Effect of spraying potassium nitrate on some vegetative characteristics of olive cv. Picual from 2009 to 2011 seasons... Effect of spraying potassium nitrate on N, P and K contents of olive leaves cv. Picual during 2009 and 2010 seasons... 109 109 112 112 115 115 119 119 120 120 123 123 VIII

33. 34. 35. 36. 37. Effect of spraying potassium nitrate on yield and alternate bearing index of olive cv. Picual from 2009 to 2011 seasons... Effect of spraying potassium nitrate on fruit dimensions and fruit shape index of olive cv. Picual from 2009 to 2011 seasons... Effect of spraying potassium nitrate on weights of fruit, flesh and seed of olive cv. Picual from 2009 to 2011 seasons... Effect of spraying potassium nitrate on flesh and seed weight percentages of olive cv. Picual from 2009 to 2011 seasons... Effect of spraying potassium nitrate on flesh dry weight and flesh oil content percentage of olive cv. Picual from 2009 to 2011 seasons... 127 127 128 128 131 IX

No. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. LIST OF FIGURES Title content from indole acetic acid in 2009/2010 season. content from indole acetic acid in 2010/2011 season content from gibberellic acid in 2009/2010 season. content from gibberellic acid in 2010/2011 season... content from abscisic acid in 2009/2010 season... content from abscisic acid in 2010/2011 season... content from zeatin in 2009/2010 season..... content from zeatin in 2010/2011 season..... content from kinten in 2009/2010 season.... content from kinten in 2010/2011 seasons.. content from benzyl adenine in 2009/2010 season.. content from benzyl adenine in 2010/2011 seasons... Page 59 59 60 60 61 61 64 64 65 65 66 66 X

13. 14. 15. 16. Effect of gibberellic acid spraying at 75 ppm on first December on floral buds differentiation in mid December and first January of olive cv. Picual during 2010/2011 season.... Effect of gibberellic acid spraying at 75 ppm on first December on floral buds differentiation in mid January and first February of olive cv. Picual during 2010/2011 season.... Effect of gibberellic acid spraying at 75 ppm on first December on floral buds differentiation in mid February and first March of olive cv. Picual during 2010/2011 season..... Effect of gibberellic acid spraying at 75 ppm on first December on floral buds differentiation in mid March and first April of olive cv. Picual during 2010/2011 season..... 69 70 71 72 XI

INTRODUCTION Olive (Olea europaea L.) is a species of a small tree in the family Oleaceae, native to the coastal areas of the eastern Mediterranean Basin (the adjoining coastal areas of southeastern Europe, western Asia and northern Africa) as well as northern Iran at the south end of the Caspian Sea. The family Oleaceae contains about 22 genera and 500 species, most of which are placed in the Oleoideae subfamily with olive. Olive is by far the most economically important member of the family, but several others are important ornamentals: Fraxinus (Ash), Syringa (Lilac), Ligustrum (Privet), Jasminum (Jasmine), Forsythia, Osmanthus (Fragrant olive), and Chionanthus (Fringe tree). The genus Olea contains about 20 species. Olive is a long-lived, sub-tropical evergreen tree, one of the oldest cultivated trees in the history of the world. Over the years, the olive has been the symbol of peace, wisdom, glory, fertility, power and pureness. The olive tree and olive oil are mentioned seven times in the Quran. Fruits are the main crop of trees, which may be used for pickling both types green and black, or may be used to extract the oil, which has a great importance in terms of food, medical, and enters also in the manufacture of cosmetics and other industries. The olive leaves are used in the manufacture of some pharmaceuticals, also the trees wood can be used in furniture industry and manufactures of wood. Therefore, the olive trees upon the economies of many countries, especially the Mediterranean basin countries. The olive cultivars are divided to oil cultivars such as Croatina, Koroneiki, Frantoio, Arbequina and Maraki or Pickling cultivars green

and black, like Toffahi, Aggizi Shami, Dolce and Kalamata or dualpurpose cultivars, such as Picual, Manzanillo and Wateken. According to the statistics of the Food and Agriculture Organization (FAO, 2012), the world area cultivated with olive trees in 2010 as shown in Table (1) is about 9532923 hectares and world production of olive are 20632686 tons fruits and 3269249 tons oil. The major countries of olive production are Spain, Italy, Greece, Turkey, Syria, Morocco, Tunisia, Egypt, Algeria, and Portugal. In Egypt, according to the last statistics from the Ministry of Agriculture and Land Reclamation (2012), the area cultivated with olive trees in 2009 reached 158058 feddans, fruiting area reached 110186 feddans producing 449009 tons (Table 2). South Sinai, Martha Matruh, El-Nobaria, El-Fayoum, North Sinai, and El-Wady El-Gadid are the most important areas of olive production. Alternate bearing is a widespread problem for growers of fruit trees, occurring in both evergreen and deciduous trees. The term alternate or biennial bearings are used by horticulturists to designate the production of a heavy fruit crop on year followed by a light crop or trees may not bear a crop at all the next off year. It can affect a large area or just individual trees or even part of a tree. Alternate bearing is more pronounced in old productive trees (more than 10 years) in comparison with the young productive trees (about 3 5 years). Tree that have become biennial flower profusely and carry a heavy crop in the on year, and flower sparsely or not at all and carry little or no crop the following year, the off year. Fruit in the on year tend to be small and low quality, while the few fruit in the off 2