Published online by Cambridge University Press: 13 August 2009
Introduction
Aspects of nutrient uptake by roots and of mineral nutrition in relation to vegetative growth and fruiting have been discussed in earlier chapters. Fruit mineral content in relation to storage and eating quality was considered in Chapter 10 and calcium uptake, transport and effects on cell structure and metabolism were discussed in particular detail because of its dominant rôle with respect to fruit firmness and the incidence of some pre- and post-harvest physiological disorders. In the present chapter more general aspects of the uptake, transport and redistribution of nutrients are dealt with.
Nutrient requirements
A first approximation of the necessary supply of major elements for apple and pear tree growth is obtained by measurement of the mineral content of well-grown and productive trees. Relevant figures from Washington State, USA are given in Table 11.1. These are for an old-style orchard at maturity, with a similar cropping level but most probably more vegetative dry matter than many modern orchards on dwarfing rootstocks. Most of the nutrients removed from the soil and not returned to it are in the fruits so the need to replace nutrients is largely a function of crop yield. Where yields are much higher, e.g. in South Africa and, especially, New Zealand the replacement needs will be much greater. Losses by leaching can be appreciable under conditions of high rainfall or irrigation on appropriate soil types.
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.