Cyclaneusma (Naemacyclus) needle-cast of Pinus radiata in New Zealand. 2: Reduction in growth of the host, and its economic implication.
Year: 1984
Type: article
Abstract: Twenty pairs of 9-year-old final-crop trees were selected in a stand of Pinus radiata D. Don heavily infected with Cyclaneusma minus (Butin) DiCosmo et al. at Kaingaroa State Forest in 1977. Each pair consisted of one heavily diseased tree and one healthy tree. Disease severity, in terms of percentage of crown infected, was recorded annually. Relationships between disease severity and growth were studied by complete stem analysis at tree age 15 years. Annual volume increments of the diseased trees were significantly reduced from age 7 onwards. Reduced diameter growth in the lower parts of the stem of the diseased trees caused small changes in the relative diameter distribution. The relationship between disease severity and volume loss showed a reduction of the average volume increment of approximately 60 % at an average disease severity of 80%. Stand growth was projected to age 30 for various proportions of diseased trees. For each 10 % increase in the proportion of diseased trees a reduction in total volume of 10-14 m3/ha and a subsequent reduction in revenue at clearfelling of $60O-$70O/ha may be expected under the given stand conditions. Nine pairs of trees were injected with a solution of carbendazim fungicide in 1980 and 1981 in an attempt to control the disease. Injection with the fungicide gave a significant growth response associated with a trend to reduced disease severity. Some of the growth response may have been attributable to a nutritional effect as it occurred in healthy and diseased trees.
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDGs: Life on land, Zero hunger
Open Access status: diamond
OpenAlex ID: W809037449