Previous screenings have found resistance to M. enterolobii in cattley guava (Psidium cattleyanum Sabine) genotypes, but not in guava (P. guajava). This study aimed to evaluate inarching between the guavas 'Paluma' and cattley as a mean to obtain nematode-resistant guava plants. Eighty 'Paluma' plantlets were produced from stem cuttings and cultivated in 5L pots (one plant per pot) until they reached a stem diameter of about 8 mm at 10 cm from the collar. Cattley guavas were obtained from true seeds of the accessions 115, 116 and 117. When all the plants reached a stem minimum diameter for inarching, two cattley guava seedlings were transplanted to each of the 5L pots, into holes of about 280 cm³ dig on each side of the 'Paluma' plants. For inarching, a cut was made in the 'Paluma' stem, and one of the cattley guava or 'Paluma' seedling was inserted under the bark. The other side plant remained as a blank control. Every 20 days the following variables were evaluated: fusion of tissues between the grafted plants and growth of the plants´ stem diameter. Successful inarching, as measured by initial connection between vascular tissues and survival of the plants, occurred more often between 'Paluma' plants than between 'Paluma' and cattley guava. Nonetheless, in the long term the plants often failed to develop functional vascular connection, since removing the root system of 'Paluma' plants resulted in their death, since root system of the cattley guavas were unable to sustain their nutrition. In conclusion, more study is needed to develop inarching as a method to produce guava rootstocks.
Psidium guajava Lineu; Psidium cattleyanum Sabine; vegetative propagation; phytonematodes control
