Abstract Macadamia trees produce high quality nuts, and many Brazilian regions present ideal conditions for their cultivation. Aiming for financial returns during the first years of cultivation, macadamia have been grown as a coffee intercrop. Some Meloidogyne species are injurious to coffee trees, although information concerning the parasitism of these nematodes in macadamia nut trees is scarce. In this context, the aim of the present study was to evaluate the host status of seven varieties of macadamia nut tree (‘HAES-344’, ‘HAES-660’, ‘HAES 816’, ‘IAC 4–12B’, ‘IAC 9–20’, ‘IAC 4–20’ and ‘Aloha 10–14’) to Meloidogyne incognita race 2, M. paranaensis and M. exigua and to determine the life cycle dynamics of these nematodes in the ‘Aloha 10–14’ variety. For the resistance test, plants were infested with 5,000 eggs and J2 of Meloidogyne spp. Evaluations were carried out at 120 days after inoculation. The Gall index (GI), egg mass index (EMI) and reproduction factor (RF) were determined. To evaluate the life cycle of the Meloidogyne species in Aloha 10–14 roots, this variety was infested with approximately 300 juveniles of each species. Evaluations were carried out at 5, 15, 25 and 35 days post-inoculation. The progenies of all studied varieties were resistant to the assessed nematode species, and can be used as rootstock. The nematode life cycle was not completed in roots of the Aloha 10–14 variety, even at 35 days post-inoculation. Macadamia proved to be a good cultivation option for areas infested with root-knot nematodes.

中文翻译：

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澳洲坚果品种根结线虫种群发展

摘要 澳洲坚果树生产优质坚果，巴西的许多地区都为它们提供了理想的种植条件。为了在种植的最初几年获得经济回报，澳洲坚果已被种植为咖啡间作。一些根结线虫物种对咖啡树有害，尽管关于这些线虫寄生在澳洲坚果树中的信息很少。在此背景下，本研究的目的是评估七种澳洲坚果树（'HAES-344'、'HAES-660'、'HAES 816'、'IAC 4-12B'、'IAC 9-20'、'IAC 4-20' 和 'Aloha 10-14') 到南方根结线虫种族 2、M. paranaensis 和 M. exigua 并确定这些线虫在 'Aloha 10-14' 中的生命周期动态种类。对于抗性测试，植物被 5,000 个卵和根结线虫的 J2 侵染。在接种后120天进行评价。测定了Gall指数(GI)、卵质量指数(EMI)和繁殖因子(RF)。为了评估 Aloha 10-14 根中根结线虫物种的生命周期，该品种被每个物种约 300 只幼鱼侵染。在接种后第 5、15、25 和 35 天进行评估。所有研究品种的后代都对评估的线虫物种具有抗性，并可用作砧木。即使在接种后 35 天，Aloha 10-14 品种根部的线虫生命周期也未完成。澳洲坚果被证明是根结线虫感染地区的良好栽培选择。为了评估 Aloha 10-14 根中根结线虫物种的生命周期，该品种被每个物种约 300 只幼鱼侵染。在接种后第 5、15、25 和 35 天进行评估。所有研究品种的后代都对评估的线虫物种具有抗性，并可用作砧木。即使在接种后 35 天，Aloha 10-14 品种根部的线虫生命周期也未完成。澳洲坚果被证明是根结线虫感染地区的良好栽培选择。为了评估 Aloha 10-14 根中根结线虫物种的生命周期，该品种被每个物种约 300 只幼鱼侵染。在接种后第 5、15、25 和 35 天进行评估。所有研究品种的后代都对评估的线虫物种具有抗性，并可用作砧木。即使在接种后 35 天，Aloha 10-14 品种根部的线虫生命周期也未完成。澳洲坚果被证明是根结线虫感染地区的良好栽培选择。并可用作砧木。即使在接种后 35 天，Aloha 10-14 品种根部的线虫生命周期也未完成。澳洲坚果被证明是根结线虫感染地区的良好栽培选择。并可用作砧木。即使在接种后 35 天，Aloha 10-14 品种根部的线虫生命周期也未完成。澳洲坚果被证明是根结线虫感染地区的良好栽培选择。