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- Author or Editor: S.I. Walter x
System requirements for organic strawberry (Fragaria × ananassa) runner production under cover were determined during the 2001-02 and 2002-03 seasons. In the field, yield and fruit quality were assessed for organically produced runners (plug and bare-rooted transplant) in comparison with barerooted conventionally produced runners under organic, BioGro certified production conditions. The preferred organic production system was the enhanced suspended system, where mother plants grew on benches in the tunnel house and the first two runners were potted into growth substrate. This system produced approximately 50 plug transplants/mother plant or 200 plug transplants/m2. The least preferred system was the nursery bed, where mother plants were allowed to produce runners that yielded approximately 100 bare-rooted runners or 100 transplants/m2. Tunnel house production of runners (plug transplants and bare-rooted) allowed earlier planting (March vs. May) compared to field-produced bare-rooted runner plants. The earlier planting date increased yield by approximately 181 g/plant. Under organic production conditions, organically produced runners (plug and bare-rooted transplants) performed at least as well as bare-rooted conventionally produced runners. Our results show that indoor production of organic strawberry runners is possible. We also showed that organically produced runners (bare-rooted and plug transplants) perform similarly in the field compared to bare-rooted conventionally produced runners. Generally, there were no differences in yield or fruit quality among runner sources.
Apple packout audits were conducted during 1991 to 1993 to assess effects of five orchard systems (three cultivars, two age groups) on fruit packout and determine if relationships exist between light quality and productivity. Cultivar/rootstock combinations on 1979 T-trellis and central-leader systems had the lowest light levels and relative yields. Trees on either 1979 3-wire trellis, 1986 MIA, or 1985 West Virginia spindle had the highest light transmission, and trees on 1979 or 1985 West Virginia spindle systems had the highest yields. Extra fancy/fancy packouts across systems ranged from 40% to 85%. `Empire', regardless of system, had the highest packouts, and `Golden Delicious' on 1979 or 1986 central leader had the lowest packouts. A regression analysis comparing percentage packout in grades below fancy to percentage full sun indicated that reduced packouts were related to low light conditions. Orchard system influenced the number of fruit downgraded due to color, russet, bruises, bitter pit, cork spot, apple scab, rots, sooty blotch/fly speck, and tufted apple budmoth. Regression analyses comparing defects to field data indicated that bitter pit decreased as yield efficiency increased, and rot and sooty blotch/fly speck incidence were related to low canopy light penetration. Revenue losses were disproportionate to percentage of downgraded fruit because some defects had a greater impact on grade than others. The greatest revenue losses were for russet in `Golden Delicious' on 1986 central leader ($1656.60/acre) and for bitter pit in `Golden Delicious' on 1979 T-trellis ($1067.30/acre). Total losses in returns for individual systems ranged from $453.71/acre for `Empire' on 3-wire trellis to $3145.49/acre for `Golden Delicious' on 1986 central leader. The comparisons of young versus mature system yields and packouts indicate that medium- to high-density vertical or inclined canopy systems are superior to horizontal or low-density vertical freestanding systems. The cost-benefit analyses prescribe areas where management can be changed in existing systems to increase profitability.