The comparative abundance of orchard pest leafroller larvae was determined on eight host plants in the vicinity of pipfruit orchards. The greatest numbers occurred in Canterbury, followed by Nelson, Hawke's Bay, and Central Otago. In Hawke's Bay, leafroller larvae were Ctenopseustis obliquana (41%), Planotortrix octo(15%), Epiphyas postvittana (16%), and Cnephasia jactatana (9%), smd were most abundant on poplar, willow, and alder. In Nelson, leafrollers were E. postvittana (25%), Planotortrix excessana (23%), C. obliquana (23%), smd C. herana (22%), found on willow, alder, clover, poplar, gorse, broom, dock, and plantain. In Canterbury, larvae were C. herana (51%), E. postvittana (34%), and P. octo (15%), mainly on broom, gorse, alder, poplar, dock, and clover. Leafrollers were very rare on host plants sampled in Central Otago, despite their pest status in horticulture. A total of 1460 larvae were reared to adults from the four regions, with 31% parasitism, of which two thirds were Dolichogenidea tasmanica (Braconidae). Parasitism varied significantly between leafroller larval host plants. Removal of leafroller host plants through mowing, pruning, careful shelter selection or other means could usefully reduce the leafroller pest density, and risk of incidence on crops.

Two apricot (Prunus armeniaca L.) cultivars, 'Sundrop' and 'Moorpark' were found to be cross-compatible with pollen of 32 genetically diverse cultivars. The flowers of 'Valleygold', 'CluthaGold', and 'Moorpark' remained receptive to pollination for up to 8 days after emasculation at the balloon stage. Floral receptivity declined in 'Moorpark', 'Sundrop', and 'CluthaGold' (but not 'Valleygold') over the 8 days. 'Sundrop' had the lowest receptivity and 'Moorpark' the highest. Percentage set of 'Sundrop' flowers varied between properties and years in Central Otago, New Zealand, with significantly lower sets being recorded in 1992 and 1993 than in 1991. In these three seasons, a 2 ha block of 'Sundrop', with no pollenisers within it, showed a decrease in fruit set as the distance from the nearest polleniser on the edge of the block increased; fruit set was unacceptably low beyond the first four or five rows. Bee density did not decline across the block in the same manner. The fruit were smaller on trees adjacent to the polleniser but were generally of similar storage quality to those from 10 rows away. The addition of extra beehives in 1992 and 1993 increased the bee numbers per tree throughout the block, but not fruit set. In comparison, another 1.7 ha block of 'Sundrop' on the same property with just 3% of the trees planted at random in the cultivar 'Trevatt', produced a better set ii each of the 3 years. Over 8 years, correlations were found between percentage fruit set and the meal temperature between 5 and 90% bloom; the number of days when the maximum temperature exceeded 18 degrees C between 5 and 90% bloom; and the meal temperature over the 3 weeks from 90% bloom. The roles of in-hive pollen exchange and self-pollination in 'Sundrop' are discussed. Planting of pollenisers within the block remains the most reliable method of increasing fruit set in large blocks of 'Sundrop'.

Flowers of the apricot (Prunus armeniaca L.) cultivar, 'Sundrop' produced low fruitset when self-pollinated or caged to exclude bees during bloom. The level of fruit set improved when 'Sundrop' flowers were pollinated with another cultivar, even when the pollen came from trees of its own progeny(the 'Clutha' series). Levels of self-compatibility varied within the 'Clutha' series; seven selections were as self-compatible as one of their parents 'Moorpark' whereas six showed low self-compatibility, similar to that of their other parent, 'Sundrop'. Comparison of tile flowering dates of these and other commercial cultivars which could be used as pollenisers showed that in four of the five years 'CluthaGold', 'CluthaStar', 'CluthaSun', and 'CluthaGem' all flowered with 'Sundrop'. However, one year demonstrated the need to include an earlier flowering polleniser for 'Sundrop'. Five of the six named 'Clutha' selections were compatible with 'Sundrop'; only lack of synchrony of flowering will affect their value as potential pollenisers for this cultivar. Three of the more commonly planted newer cultivars had low self-compatibility-'Sundrop', 'CluthaGold', and 'Valleygold'-thus revising the pollination status of apricot from a crop that does not require cross-pollination to one which generally does; care will be necessary in the planning of new plantings.

An 8-month old Welsh Cob filly had shown progressive ataxia of the hindquarters since about 3 months of age. Autopsy revealed a venous malformation resulting in malacia in the ninth thoracic segment of the spinal cord. It is proposed that the tissue destruction associated with this congenital lesion gave rise to the ataxia.

SummarySesamoid lameness poses many problems to the clinician. Owing to the complexity of the fetlock joint and its components, it is often difficult to determine the exact nature and site of the pathological changes on clinical examination. Accurate diagnosis is dependent on radiological examination but changes seen on such examinations may not be demonstrable until the condition has become chronic.Many of the lesions of the sesamoids seen on radiological examination are difficult to interpret and they relate to the clinical picture, and thus need not necessarily provide an accurate guide to the prognosis. Most cases of sesamoid lameness are related to previous primary soft tissue damage, and treatment should, in the initial stages, be directed toward this.While the prognosis should always be guarded, many animals will recover to soundness, in spite of marked pathological changes in the area.RésuméLes boiteries sésamoidiennes posent de nombreux problèmes cliniques. A cause de la complexité de l'articulation du boulet et de ses éléments il est souvent difficile de prèciser la nature et le site exact des changements pathologiques lors d'un examen clinique.Un diagnostic satisfaisant dépend souvent d'un examen radiographique; mais les changements décelables par cette technique peuvent n'etre appréciables que lorsque la condition pathologique est devenue chronique.Bien des lésions au niveau des sésamoides, rencontrées lors d'un examen radiographique, sont d'interprètation délicate, difficiles à rattacher au contexte clinique; partant elles n'ont pas nécessairement une grande utilité dans le pronostic.La plupart des boiteries sésamoidiennes sont dues à une lesion initiale des tissus mous et le traitement devrait, à son début, tenir compte de ce fait. Le pronostic doit toujours etre réservé. Pourtant de nombreux animaux retrouvent une aptitude fonctionnelle normale en dépit de déformations pathologiques marquées de cette région.ZusammenfassungGleichbeinlahmheiten stellen den Kliniker vor viele Probleme. Wegen der komplexen Verhältnisse im Fesselgelenk ist es oft schwierig die genaue Natur und den Sitz pathologischer Veränderungen durch die klinische Untersuchung zu eruieren.Die genaue Diagnose hängt ab von der Röntgenuntersuchung, aber sichtbare Veränderungen treten oft erst auf, wenn der Zustand chronisch geworden ist. Viele Gleichbeinläsionen, die im Röntgenbild zutage treten, sind schwer zu beurteilen und mit dem klinischen Bild zu korrelieren. Das Röntgenbild gibt deswegen nicht unbedingt zuverlässige Anhaltspunkte für die Prognose. Die meisten Gleichbeinlahmheiten stehen in Beziehung mit vorbestehenden Schäden des umgebenden Gewebes und die Behandlung sollte zu Beginn darauf Rücksicht nehmen. Die Prognose muss vorsichtig gestellt werden, obgleich viele Tiere trotz deutlichen Veränderungen an den Gleichbeinen sich klinisch wieder erholen.SumarioLa claudicacion sesamoidea posee varios problemas para el clinico. Sabiendo lo complejo de la articulacion del menudillo es dificil determinar exactamente la naturaleza y el sitio de la lesion. Diagnostico radiografico es aconsejable pero muchas veces no se notan los cambios hasta que la lesion no se torna cronica. Muchas de las lesiones de los sesamoideos son dificiles de interpretar radiologicamente en relacion al caso clínico y esos necesariamente necesitan de una guia de pronostico. Muchas de las lesiones delos sesamoideos primeramente son lesiones de tejidos landosm. Mientras que el pronistico deberá ser reservado muchos animales se re uperan a sanos donde existen cambios patologicos muy marcados.