FACTORS ASSOCIATED WITH SPARTAN BREAKDOWN OF APPLE by Raymond Laurent Granger A thesis submitted to the Faculty of Graduate Studies and Research of McGill University in partial fulfilment of the requirements for the degree of Doctor of Philosophy Department of Plant Science, Macdonald College of McGill University, c Montreal• March, 1979 iii - • I dedicate this thesis to my wife UIREILLE ABSTRACT FACTORS ASSOCIATED HITH SPARTAN BREAKDOWN OF APPLE DEPARTMENT OF PLANT SCIENCE RAYMOND LAURENT GRANGER Quebec-grown Spartan apples were compared with those from British Columbia in an effort to explain why B.C. fruits are more susceptible to the Spartan breakdown storage disorder. Based on fruit diameter apples were sized into small, medium and lar~e categories from Quebec and medium, large and extra large from British Columbia. Peel and flesh tissues of individual apples from each category were analysed for total N, P, K, Ca, Mg and Zn. Firmness, percent red colour, specific gravity, moisture content, titrateable acidity and percent soluble solids along with and release rates also were determined on co2 c2n4 individual fruits in every category. Large fruit size, decreasin~ firmness and high or H release co2 c2 4 rates expressed on a fruit basis were associated with Spartan breakdown development in cold storage. The predictive values of the various mineral analyses for Spartan breakdown were in the following order: peel Mg > flesh K > flesh P > flesh Mg > flesh Ca > peel K > peel Ca. The British Columbia apples contained significantly higher levels of all elements except those of N and Ca which were not significantly different in the fruit from both pr.ovinces. c i In a second experiment the clonal apple rootstocks M 26, M 7, MM 106 and MM 111 grafted to 'Spartan' and 'Delicious' were planted in pots of sand. After a period of growth the trees were depotted, pruned to the 3 basal leaves of the scion cultivar and the roots were immersed in a nutrient solution containing 45Ca. Gibberellic acid plus 6-Benzyladenine applied at the axillary buds of these leaves failed to promote their growth and interfered with 45Ca uptake. 'Spartan' trees took up more 45Ca than the 'Delicious' trees in the same time period. M 26, MM 106 and M 7 showed no signi­ ficant difference in their ability to transport 45Ca to the scion cultivar. However, al~ were significantly more efficient than MM 111. ii 0 ABREGE FACTEURS ASSOCIES AU BRUNISSEMENT DE LA POMME SPARTAN DEPARTEMENT DE PHYTOTECHNIE RAYMOND LAURENT GRANGER Un premier essai eut pour objet d'expliquer la moins grande sus­ ceptibilite au brunissement des pommes Spartan cultivees au Quebec comparativement a celles cultivees en Colombie Britannique. Des le debut on classa lea pommes du Quebec en petites, moyennes et grosses. Comparativement, celles de la Colombie Britannique furent classees en moyennes, grosses et tres grosses selon leur calibre. La pelure et la chair de fruits individuals de chaque categorie subirent une analyse en elements totaux de N, P, K, Ca, Mg et Zn. Chez ces memes fruits on evalua en outre la fermete, le pourcentage de coloration rouge, la gravite specifique, la teneur en eau, en acidite titrable et en solublea solides. En plus on mesura lea taux de respiration et de degagement d'ethylene d'echantillons de pommea preleveea dans chaque categorie. Le brunisaement de la pomme Spartan en entrepot refrigere s'aaso­ cia au fort calibre du fruit, a sa fermete ainai que son degagement de C0 ou de exprime sous une base de fruit. Lea elements qui 2 c2n4 ae aont averes lea meilleurs predicteurs du brunisaement furent, par ordre de priorite, la teneur en Mg de la pelure > en K de la chair > en P de la chair > en Mg de la chair > en Ca de la chair > en K de la pelure > en Ca de la pelure. 0 Les pommes de la eolombie Britannique se sont revelees plus riches en tous les elements excepte en N et en ea. Les pommes du Quebec ne furent pas significativement di(ferentes de celles de la eolombie Britannique quant a ces deux elements. Dans un deuxieme essai les porte-greffes clones M 26, M 7, MM 106 et MM 111 plantes dans des pots de sable furent greffes avec les cultivars Spartan et Delicieuse Rouge. Apres une periode de croissance on depota les arbres puis apres les avoir rabattus au niveau de la troisieme feuille basale du scion on en immergea le systeme radiculaire dans une solution nutritive contenant du calcium radioactif. L'acide gibberellique ainsi que la 6-Benzyladenine lorsqu'appliques sur les bourgeons axillaires de ces feuilles reduisirent la croissance des nouvelles tiges et diminuerent !'absorption du - 5ea. Le cultivar Spartan favorisa beaucoup plus !'absorption du ' 5ea que le cultivar Delicieuse Rouge. Les porte-greffes M 26, KM 106 et M 7 ne furent pas significativement differents entre eux quant au transport du ' 5ea dans la partie superieure de l'arbre. eependant ils furent signifi- / cativement plus efficaces que le MM 111. c 0 ACKNOWLEDGEHENTS I wish to thank wholeheartedly Hr. J.J. Jasmin, who on behalf of the Canada Department of Agriculture, enabled me to pursue my Ph.D. studies. My sincere gratitude is conveyed to professor C.D. Taper, Chairman, Department of Horticulture at Macdonald College and director of this thesis, for his criticisms and kind assistance. I am parti­ cularly endebted also to Dr. D.V. Fisher, director of the Agriculture Canada Research Station at Summerland, B.C. He very generously introduced me to his professional colleagues who shared their faci­ lities and enabled me to conduct the experiments described in this thesis. Very special thanks are directed to Dr. N.E. Looney, head of the Pomology Section at the C.D.A. Research Station of Summerland, B.C., whose encouragement, inspiration, enthusiasm and continued energetic support were of primordial importance. Appreciation is extended to Drs. S.W. Porritt, M. Meheriuk and Miss L. Berard C.D.A. post-harvest physiologists at Summerland and St-Jean, whose vast experience was of /great assistance to me. Similarly I wish to thank Dr. M. Faust of the U.S.D.A. Fruit Research Laboratory at Beltsville, Md, U.S.A. for his valuable advice. For guidance in statistics I wish to express my gratitude to Professor Fanous of Macdonald College, to Dr. Gilles Rousselle of Agriculture Canada at St-Jean, and to Professor G. Eaton, Plant·Science c iv 0 Department, University of British Columbia. For the statistical analysis of the data, the assistance of Mr. D. Royer, Mr. C. Mcintosh and Mr. K. Price respectively from Rt-Jean, Summerland and Ottawa was greatly appreciated. Advice and help in the laboratory by the late Mr. D. Riordan, Mr. G. Wardle, Mr. B.G. Drought and Mr. J. MacDougal from Summerland along with that of Mr. Y. Perron from St-Jean is gratefully acknow­ ledged. The efficient technical assistance of Mr. H. Schmid, Mr. B. Taylor, Mr. A. Fisher and Hiss A. l~ardle all from Summerland, has helped m~ to successfully complete my experiments. I am grateful to the photographers Mr. F. Dolezsar and Mr. L.G. Simard, respectively from Summerland and St-Jean who have taken or processed the photographs and to Mr. H.R. Jackson of the Biographic Unit at Ottawa for drawing the figures included herein. Likewise I recognize the great help of Miss c. Rolland in typing this thesis. Finally I wish to acknowledge the kind-willingness of Dr. and Mrs. J.L. Mason for exchanging their job site and facilities with me for one year. / March, 1979 V c TABLE OF CONTENTS Chapter Page ACKNOWLEDGEMENTS •• ~ • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • i V LIST OF TABLES ••••••••••••••••••••••••••••••••••• ~ •••••••••• LIST OF FIGURES •••••••••.••••••••••••••••••••••••••••••••••• 1. INTRODUCTION .•••••••••••••••• ~ ••.••••••••• ~ •.•••.••.• :........ 1 2. REVIEW OF LITERATURE~.~ •• :.:~ •••••••• ~.: •• :: •• :............... 3 2.1. Cultural Factors Associated with Apple Storage Disorders. 3 2.1.1. Introduction......................................... 3 2.1.2. Scion/rootstock relationships........................ 3 2.1.3. Irrigation, pruning and thinning..................... 4 2.1.4. Soil management, soil type and mineral content....... 6 2.1.5. Growth regulator and fungicide sprays................ 8 2.1.6. Time of harvest and post-harvest treatments.......... 9 2.2. Nutritional Factors Associated With Storage Disorders •••• 12 2.2.1. Prominent role of calcium •••••••••••••••••••••••••••• 12 2.2.2. Elements other than Ca associated with storage di- sorders •••••••••••••••••••• ~••••••••••••••••••••••••• 16 2.2.3. Cytological, physiological and environemental factors 25 3. EXPERIMENTS AND RESULTS••••••••••••••••••••••••••••••••••••••• 32 3.1. Some Differences Between Quebec (Fresniere} and British Columbia (Summerland) Spartan Apples ••••••••••••••••••••• 32 3.1.1. Physical properties and chemical constituents as they relate to Spartan breakdown •••••••••••••••••••••••••• 32 3.l.l.A. Materials and methods •••••••• ~••••••••••••••••••••• 32 3.1.1.B. Results ••• ~ ••••••••••••••• ~~ •• ~.~ •••••• ~ •••••••.••• 43 3.l.l.B.l. Development of breakdown and rots in cold storage 43 3.l.l.B.2. Fruit mineral content............................. 44 TABLE OF CONTENTS (Continued) Chapter Page 3.1.l.B.3. Fruit firmness at harvest and after storage and colour, specific gravity, and tissue moisture content at harvest •••••• ~ ••• ~ ••••••• ~ •• ~~ ••••• ~ •• 56 3.l.l.B.4. Juice acidity and soluble solids content ••••••••• 61 3.l.l.C. Discussion •••••.•••••••••••• ~.~ •••••••.••• ~· •••••••• 61 3.l.l.C.l. Development of breakdown and rots in cold storage 61 3.l.l.C.2. Fruit mineral content ••••••• ~•••••••••••••••••••• 65 3.l.l.C.3. Fruit firmness, colour, specific gravity and moisture content •••••••• ~ •••••••••••••••••••••••• 92 3.l.l.C.4. Juice acidity and soluble solids content ••••••••• 96 3.1.2. Comparison Between British Columbia and Quebec Spartan. Apples With Regard to Postharvest Respiration and Ethylene Production Rates •••••••••••••••••••••••••••• 98 3.1.2.A. Materials and methods •••••••••••••••••••••••••••••• 98 3.1.2.B. Results ••••••••••••••••••••••••••••.••••••••••••••• 101 3.1.2.B.l. Respiration' at 20 0 C of B.C.