Studies on clonal multiplication of guava (Psidium guajava L.) through cutting under controlled conditions.

Nursery experiments were conducted over three years on standardization of clonal propagation technique in Psidium guajava L. (guava) through rooting of cuttings. Influence of various factors such as potting mixtures (vermiculite, sand and soil), cutting size (5, 10 & 15 cm) and seasonal changes (summer, rainy & winter), were studied on adventitious root formation in the guava cuttings. The study revealed significantly higher root induction (90+/-3.87%) in vermiculite followed by sand (50+/-4.16%). Root formation was retarded when soil was used as potting medium (8.02+/-1.85%). Accordingly callus formation varied greatly among various potting medium (10.11 to 98%). There is slight difference between 10 and 15 cm long cuttings in terms of root induction (82.8 to 91%). However, it was markedly declined (30%) in smaller cuttings (5 cm long). Rooting potential of cuttings (82.0 to 90%) was marginally effected by seasonal variation. Exogenous application of nutrient solution (half strength Hoagland) promoted formation of strong root system with several brush shaped fibrous roots. The study provided useful information on clonal multiplication of elite germplasm of guava under protected environment for developing commercial nurseries.