Optimized cutting of yellow passion fruit and its potential for unstaked or trellised cultivation

Abstract: The objective of this work was to evaluate types of cuttings, indole-3-butyric acid (IBA) concentrations, and potting media on the rooting of passion fruit (Passiflora edulis) cultivars, and to compare the initial performance of flowering-competent cuttings cultivated in a trellising system or in a nonstaking method on ground covered with plastic mulch. The passion fruit cultivars evaluated were BRS Gigante Amarelo, Isla Redondo Amarelo, and FB 200 Yellow Master were evaluated. The assessed treatments were: softwood or semi-hardwood cuttings; five concentrations of IBA (0, 500, 1,000, 2,000, and 4,000 mg L-1); and the pine bark or phenolic foam potting media. Initial growth, fruit yield, and bacteriosis severity were evaluated in the field in flowering-competent cuttings and seedlings, both in the trellising system and in the nonstaking method on mulched ground. For the evaluated cultivars, a high rooting rate (>90%) was observed for both softwood and semi-hardwood cuttings grown in phenolic foam or decomposed pine bark for potting media, regardless of the IBA concentration. In the espalier system, 14 months after transplanting, fruit yield was 45% higher for cuttings than for seedlings. Unstaked plants had a low number of flowers and fruit set, and a great damage by bacteriosis according to the used cultivar. The evaluated cultivars can be propagated either by softwood or semi-hardwood cuttings, in phenolic foam or decomposed pine bark, without IBA application. Flowering-competent cuttings have the potential to anticipate the production in the trellised cultivation of yellow passion fruit.摘要：本研究旨在探究插条类型、吲哚-3-丁酸（IBA）浓度以及栽培基质对西番莲（Passiflora edulis）品种生根效果的影响，并对比棚架栽培系统与塑料地膜覆盖无架栽培模式下，具备开花能力的插条的初期生长表现。供试的西番莲品种包括BRS Gigante Amarelo、Isla Redondo Amarelo以及FB 200 Yellow Master。评估的处理组设置如下：嫩枝插条与半硬枝插条；5种IBA浓度梯度（0、500、1000、2000、4000 mg·L⁻¹）；以及松树皮与酚醛泡沫两种栽培基质。本研究在田间对具备开花能力的插条与实生苗分别开展评估，涵盖初期生长量、果实产量以及细菌性病害严重程度，两种供试材料均设置了棚架栽培与塑料地膜覆盖无架栽培两种模式。针对供试品种，无论IBA浓度如何，采用酚醛泡沫或腐熟松树皮作为栽培基质时，嫩枝插条与半硬枝插条的生根率均可达到90%以上。在棚架栽培系统中，定植后14个月，插条植株的果实产量较实生苗高出45%。无架栽培植株的花量与坐果率均较低，且不同品种受细菌性病害的危害程度存在显著差异。供试西番莲品种可通过嫩枝或半硬枝插条，以酚醛泡沫或腐熟松树皮作为栽培基质进行无性繁殖，无需施加IBA。具备开花能力的插条可显著缩短黄色西番莲棚架栽培的投产周期，具备良好的应用前景。