Isotope-Aided Research in Fruit and Vegetable Crops

Abstract

In the realm of newly-emerging horticultural enterprises, some of the tracer- or isotope-related applications are highlighted here. These include root activity studies on important fruit crops using soil injection of carrier-free ³²P, factors affecting spatial temporal root activity distribution of fruit crops, appropriate time and method of application to achieve maximum use efficiency in fruit and vegetable crops using ¹⁵N- and ³²P-labelled fertilizers. A model for studying nutrient efficient cropping sequences and crop combinations in vegetable crops was also developed. Other uses of radiation techniques in plant nutrition are: mobilization of P from mother plant to sucker in 'Robusta' banana, contribution of exogenous fertilizer source to phosphorus availability in citrus, internal dilution technique for comparing sources not amenable to isotope labelling, determination of tree volume in fruit crops using isotope dilution technique, detection of unorthodox movement of nutrients upon direct feeding of nutrients to de-navelled banana bunch, monitoring internal dynamics of water in spongy-tissue affected 'Alphonso' mango fruits, investigations on source-sink relationship in mango and some vegetable crops, identification of high water use efficient types using ∇¹⁸O values in onion, etc. Scope of using tracer techniques in horticultural research is highlighted.