Development and application of biotechnology in Guava: a nutraceutical fruit

Fruits and vegetables have specific healthy attributes. Guava is the most nutritious of all edible fruits. High pectin contents make guava suitable for jelly making. Guava has antidiarrheal, antibacterial, antiamoebic and antispasmodic activities. High concentrations of several vitamins, dietary fiber, carotenoids, lectins, saponins, tannins, phenols, triterpenes, and flavonoids altogether make guava therapeutically an important fruit. Ascorbic acid in guava fruit far exceeds that in citrus. Consumption of guava fruit is reported to lower blood cholesterol, triglycerides, hypertension and some cardiac problems. Due to high quercetin contents, guava leaves are used to develop a phytomedicine for diarrhea. Since guava plant is susceptible to frost, genetic improvement to enhance cold hardiness of guava germplasm is necessary for adapting and cultivating it in temperate climates. Efficient and reliable biotechnology using in vitro plant regeneration amenable to genetic transformation will ensure cold hardiness enhancement in guava. Development of biotechnology protocols for morphogenesis and somatic embryogenesis along with production of edible quality guava fruits and their nutritional analysis has been achieved using various tissue explants from mature guava trees growing at Fort Valley State University. For guava micropropagation, we have developed and germinated 'synseeds' from somatic embryos. Successful preliminary work on genetic transformation has paved the way for incorporating cold hardy genes into the guava genome.