Horticultural Reviews, Volume 45

Professor Ian James Warrington CNZM is a Palmerston North horticultural scientist and science administrator. He was former chief executive of HortResearch (now Plant & Food Research). He was a senior administrator at Massey University until his position was axed in a cost-saving move. He received the T. K. Sidey Medal in 1984, an award set up by the Royal Society of New Zealand for outstanding scientific research. He was appointed a Companion of the New Zealand Order of Merit (CNZM) in the 2011 New Year Honours.

• Contributors ixDedication: Jules Janick xiiiIan Warrington1. The Flowers of Fragaria × ananassa: Morphology, Response to Photoperiod, and Genetics of Induction 1Andrew Petran and Emily HooverI. Introduction 2II. Strawberry Growth, Reproduction, and Commercial Management 2III. Inflorescence Architecture 13IV. Genetics of Flower Induction 16V. Conclusions 26Literature Cited 272. Small Unmanned Aircraft Systems (sUAS): An Emerging Technology for Horticulture 33James A. RobbinsI. Introduction 35II. Aircraft 36III. Sensors and Data Processing 42IV. Horticultural Applications 52V. Challenges 61VI. Conclusions 64Literature Cited 643. Leaf Blackening: A Serious Impediment to Long‐Term Cold Storage, Transport, and Extended Vase Life in Protea Cut Flowers 73Eleanor W. Hoffman, Waafeka Vardien, Gerard Jacobs, and Nicole E. WindellI. Introduction 74II. Variation in Expression of Leaf Blackening 76III. Physiological Causes of Leaf Blackening 80IV. The Biochemical Mechanisms of Leaf Blackening 87V. Control of Leaf Blackening 90VI. Conclusions 99Literature Cited 1004. Sapota (Manilkara achras Forb.): Factors Influencing Fresh and Processed Fruit Quality 105Babak Madani, Amin Mirshekari, Elhadi Yahia, and John B. GoldingI. Introduction 107II. Nutritive Value 111III. Physiological and Biochemical Changes During Fruit Maturation and Ripening 114IV. Preharvest Effects on Postharvest Quality 120V. Physiological Disorders 121VI. Postharvest Diseases 122VII. Postharvest Technology 123VIII. Postharvest Treatments 126IX. Non‐Destructive Methods for Identifying Fruit Maturity and Quality 131X. Processing 132XI. Summary and Future Prospects 134Literature Cited 1365. The Citron (Citrus medica L.) in China 143David Karp and Xulan HuI. Introduction 145II. History and Culture 145III. Nomenclature 147IV. Current Citron Cultivation in China 148V. Major Cultivars of Chinese Citron and Select Citron Hybrids 158VI. Germplasm Status; Regional and Global Perspective 190Literature Cited 1926. Apple Rootstocks: History, Physiology, Management, and Breeding 197Richard P. Marini and Gennaro FazioI. Introduction 198II. History 199III. Rootstock–Scion Interactions 204IV. Stresses Influencing Rootstock Performance 225V. Interstems 259VI. Influence of Rootstock on Fruit Characteristics 262VII. Genetics and Breeding 266VIII. Rootstock Evaluation 277Literature Cited 2827. Canopy Growth and Development Processes in Apples and Grapevines: Responses to Temperature 313Dennis H. GreerI. Introduction 315II. Phenology 316III. Dormant Buds in Apple Trees and Grapevines 317IV. Winter Chilling in Apple Trees and Grapevines 319V. Budbreak and Shoot Development in Apple Trees and Grapevines 320VI. Fruit Growth 332VII. Biomass Partitioning 338VIII. Photosynthesis and the Carbon Economy 340IX. Abiotic Stress Effects on Canopy Physiology 349X. Impact of Climate Change on Phenology 355XI. Conclusions 357Literature Cited 3588. Organic Acids in Fruits: Metabolism, Functions and Contents 371Robert P. Walker and Franco FamianiI. Introduction 373II. The Function of the Flesh of Fruits and its Implication for their Organic Acid Contents 375III. Acids that Contain a Benzene Ring: The Aromatic Acids 377IV. The Inter‐Related Acids: Ascorbic, Oxalic, Tartaric, and Galacturonic 385V. Fatty Acids 398VI. Malic, Citric, and Metabolically Related Acids 399VII. Conclusions 412Literature Cited 413Subject Index 431Cumulative Subject Index 435Cumulative Contributor Index 473