Organic growers face the same potentially severe pest problems as non-organic farmers. By contrast, the organic farmers have a very limited range of approved products with which to control these problems. In many countries, very few fruit farmers even dare trying to grow with the less effective organic pest control methods.
“The demand for organic pears in North-western Europe is high compared to the limited production. In spite of the good market perspective there are very few pear growers in the Netherlands who dare convert to organic production. The most prominent reason for this is their fear of scab (Venturia pirina). And indeed it is the experience of those who are growing organically that it is very hard to control this important disease. This is even more so since Copper based products were banned as fungicides in the Netherlands.”
Author: Jansonius, P. J.
Affiliation: Louis Bolk Institute, Hoofdstraat, NL
Title: Conference pears; work on system changes to enable better scab control in organic orchards in the Netherlands.
Source: Ecofruit Proceedings. 2008.
Records suggest that China has cultivated pears for well over 2500 years. China ranks first in the world in pear production, growing 75% of the world’s output. Annual production has increased twenty-fold in China since the 1950s. A key to production is protecting pears from a disease known as pear scab, which is caused by a fungus that overwinters in leaves on the ground. Spores are released as a result of rain and are carried by air currents to leaves and fruit. Scab lesions form on fruit and, as they enlarge, become large black areas. Fungicides are used in China to prevent pear scab infections.
“Pear scab (Venturia nashicola) is an economically important disease in China. The pathogen is different from the European pear scab fungus (V. pirina) and causes significant annual yield loss on pears, especially on traditional Chinese varieties. … Infection by V. nashicola can occur at any time throughout the growing season from early spring until late autumn, if environmental conditions are conducive. Leaves and fruits become gradually less susceptible to infection as they age. Pear scab in China is managed by routine application of fungicides.”
Authors: Li, B.-H.¹, J.-R. Yang², B-D. Li¹ and X.-M. Xu³
Affiliation: ¹Laiyang Agricultural College, Shangdong Province, China; ² Northwest A & F University, Shaanxi, China; ³ East Malling Research, Kent, UK.
Title: Incidence-density relationship of pear scab (Venturia nashicola) on fruits and leaves.
Publication: Plant Pathology. 2007. 56:120-127.