Effect of intermittent shading on growth, flowering and nutrient uptake of passionfruit

摘要: Abstract Passionfruit plants ( Passiflora edulis f. × P. flavicarpa cultivar ‘E-23’) were grown under various periods of full sun and shade, but with some the receiving similar amounts total shortwave radiation. Low irradiance treatments, i.e. 90% shade; 1 week sun:3 weeks 50% alternate 3 sun:1 generally increased vine extension reduced plant dry weight floral bud open flower number compared or shade. The effects shading on growth flowering stronger shorter heavy shade (90%) than longer intermediate (50%), when average irradiances during experiment (16.5 15.4 MJ m −2 day −1 11.2 10.0 ). concentrations most nutrients significantly higher from full-sun only levels in range considered to be optimum for passionfruit subtropical Queensland. exceptions leaf N, Mg Cu, which low all treatments. Values shaded fell into same category standard table. exception was B vines. It concluded that intermittent have residual sun. Short as little out 4 can reduce potential yield significantly. These results suggest increases density lead inter-vine will decrease fruit set.