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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2020

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Abstract

Controlled crosses were made on clones in a seed orchard and the pollination bags were kept on the branches until the cones were harvested. Cones after open pollination were collected at the same time. Seedlings from the controlled pollinations, from open pollination of the same maternal parent and from commercial provenances were grown in growth chambers and terminal bud set was recorded after short day treatments. The seedlings from the seeds of cones that were kept in the pollination bags had a significantly later bud set then expected based on comparisons with their half-sibs from open pollination. The difference corresponds to a decrease in altitude of 100 m at provenance level. It can be caused by epigenetic effects due to temperature differences inside and outside the bags during seed maturation.

Abstract

The objective of this paper is to examine the economic performance of crop-producing farms accounting for unobserved heterogeneity,environmental variables, and regions. The empirical analysis was based on a translog cost function and unbalanced farm-level panel data for 1991–2013 from the 455 crop-producing farms with 3,885 observations (1,004observations from the central region and 2,881 observations from the eastern region). We found that the mean minimum costs were about 93% and 92% of the actual costs for crop farms in the central and eastern regions, respectively.The marginal effects of crop rotation, land tenure, off-farm activity, direct government support, and experience were positively associated with crop farm economic performance. The marginal contribution of these variables on economic performance increased in the years 2000–2013 compared with the years 1991–1999 in both regions.