THE APPLICATION OF SCIENTIFIC TECHNIQUES TO FRUIT AND NUT PRODUCTION IN THE TROPICS
This paper considers two aspects of tropical fruit research, the application of isozyme methods to genotype discrimination in citrus, and the study of pollination problems in cashew. Isozyme analysis was used to distinguish zygotic from nucellar embryos of five polyembryonic citrus rootstocks. Using eight loci of six enzyme systems zygotic seedlings were detected in rough lemon (2.1%), trifoliata orange (2.6%), sweet orange (0.8%) and Troyer citrange (0.8%), but not in Cleopatra mandarin. These zygotic seedlings could not be discriminated from the nucellars on the basis of their morphology. Similar techniques were used to investigate relationships between mandarin cultivars and hybrids. Isozyme analysis using nineteen loci of sixteen enzyme systems was applied to nineteen mandarin genotypes. All but three of the mandarin genotypes could be discriminated and two of these were probably identical. Experiments were conducted to study pollination in cashew. There was specific combining ability amongst five cashew genotypes as measured by pollen tube growth, and general combining ability as measured by final nut set.
Sedgley, M., Ashari, S. and Wunnachit, W. (1992). THE APPLICATION OF SCIENTIFIC TECHNIQUES TO FRUIT AND NUT PRODUCTION IN THE TROPICS. Acta Hortic. 292, 61-68