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In order to develop a method for extensive pomiculture on marginal soils in semiarid Brazil, a field experiment was conducted to study the impacts of the soil conditioners biochar, clay substrate and goat manure on soil physical parameters of a sandy soil and on seedling performance ofSpondias tuberosaArruda. Manure significantly increased total porosity, soil water content and reduced bulk density of the sandy soil. Water content at field capacity (θfc) and at permanent wilting point (θpwp) were increased due to manure application. Neither biochar nor clay substrate had a significant impact on the soil physical parameters. Biochar combined with clay substrate led to lower soil water content and significantly reduced the period of retaining atmospheric water. Due to a strong correlation (R2 = 0.75) betweenθfcandθpwp, the available water capacity within all treatments remained unchanged. Amelioration and initial nutrient supplies had no effect on seedling survival and stem growth ofS. tuberosaduring the 23-month experiment. This underlines the nondomesticated character of the available plant material ofS. tuberosa. The independence of the seedling performance of soil management makesS. tuberosaan interesting species for low-input orchards and for reforestation within the Caatinga. [ABSTRACT FROM PUBLISHER]

Cultivation of important woody species with the goal of conserving them is hampered by little, or no, information on how such species can be propagated or their seedlings established. We investigated propagation and seedling establishment of 14 important multipurpose species much valued for traditional medicine in Uganda. The experiments included sexual and vegetative propagation, as well as a seedling growth experiment. The multipurpose speciesPsidium guajava, Markamia lutea, Maesopsis eminiiandSpathodea campanulatapropagated easily from seed, andFicus natalensisfrom cuttings. The medicinal speciesZanthoxylum leprieurii, Warburgia ugandensisandFicus saussureanadid not germinate at all.Toddalia asiaticaandCanarium schweinfurthiihad high dormancy and low synchrony of seed emergence.Markamia luteaseedlings established readily with addition of fertilizer (NPK) and moderate watering (three times a week). We conclude that whereas the multipurpose use species appear to propagate easily, the medicinal plants are difficult to propagate sexually or asexually. [ABSTRACT FROM AUTHOR]

Feeding by the tarnished plant bug ( Lygus rugulipennis Popp.) has caused severe damage in Norwegian nurseries. Large quantities of seedlings have been removed after sorting. The life cycle of the insect has been well studied and documented. This study was a first attempt to investigate how the seedlings develop after the insect attacks. The first visible sign of damage is the development of multiple terminal buds. Two-year-old containerized seedlings were planted and followed for 4 years. Before planting, the seedlings were sorted into three damage classes: 0, undamaged; I, moderately damaged, up to 10 fully developed buds; and II, severely damaged, 10–20 small buds and no dominant apical bud. The damaged seedlings were somewhat shorter at planting but this difference disappeared with time. The seedlings in the two damage classes differed in their development of multiple shoots. At the end of the 4 year period about 50% of the seedlings in class  II and about 20% from class I still had multiple leaders, or lateral stems or side branches that would probably produce spike knots in the future. The sorting routine currently used at the nursery was found to reduce the problem to an acceptable level for seedlings that were planted in the forest. [ABSTRACT FROM AUTHOR]