Stem bulging disorder in passionfruit (Passiflora edulis f. flavicarpa)
Stem bulging in passionfruit is a disorder observed especially in the Low Country Wet Zone of Sri Lanka. Symptoms of swelling and/or with cracking on certain portions of the stem are observed at any stage of the growth. The problem is associated with yield decline and shortening of life span. Experiments were carried out to find out the potential of boron in minimizing the disorder. Five treatments including three levels of soil application (10, 20 and 30 g borax plant-1 year-1) and one level of foliar application (0.2% Borax) with a control were tested in randomized complete block design in four replicates at Horana (6°45.21'N; 80°03.56'E), Sri Lanka. Soil treatments were given in two splits as basal and 3 months after planting (MAP) and foliar spray was given monthly started one month after planting. The soil was Red Yellow Podsolic with sandy loam texture, 1440 ppm calcium, 5.8 pH and 0.2 ppm boron. Symptoms appeared at two MAP in the control and eight MAP in the foliar treatment. Surface area of bulges at 10th month of planting was lowest in the foliar treatment. Results revealed that monthly foliar application of 0.2% borax was effective in minimizing stem bulging disorder in passionfruit grown in a soil with deficient level of boron.
Wanniarachchi, S.D.R., Karunatileke, M.S., Wickramasekara, P.G.R.K., Peiris, V.K. and Wickramasinghe, C.D. (2017). Stem bulging disorder in passionfruit (Passiflora edulis f. flavicarpa). Acta Hortic. 1178, 175-178
boron, calcium, cracking, deficiency, node swelling