<正>应用参与式技术发展方法，通过对毛竹笋用林培育技术问题的诊断，设计了以全面支持对毛竹笋用林开展肥培管理、改善施肥时间和发展测土施肥等3个技术层面的农民参与式技术发展方案，对笋用林施肥管理技术进行试验、提升和推广。研究表明，应用测土施肥技术可提高毛竹冬笋产量1.2～6.8倍，净产值提高1.4～3.9倍。通过技术发展过程中多个利益相关群体的参与及合作，提高了该技术的地方适应性、农民的试验能力和技术推广人员解决生产问题的能力。

In order to study hybrid vigour of larch, select the optimal combinations of high growth yield and supply production with fine variety,the diameter growth of 63 larch families in 23 years old from the progeny trial in Linkou, Heilongjiang province was measured and analysed. The results show that there is an extremely significant difference in yield of larch interspecies. Hybrid larch has obvious growth predominance, especially the hybrid vigour of Larix kaempferi as female parent and L. olgensis and L. gmelini as male parent is more obvious. Hybrid vigour is 3. 2% and superparent vigour is 3. 1% in the combination of L. kaempferi×L. olgensis. The growth of L. kaempferi×L. gmelini and L. leaempf eri×L. olgensis exceeds that of check of local of larch by 15.1% and 13.4% respectively. Because the differences of interspecific families and intraspecific families reach a remarkable level, selection for intraspecific parent individuals should be valued on the basis of fully utilizing interspecific hybrid vigour. The averages of 10 good families that have been selected exceed that of check by 34. 1%. They are good for spreading in Mudanjiang area. It shows a significant difference in diameter growth between the reciprocal crosses of L. kaempferi×L. gmelini and L. gmelini×L. kaempferi. Average growth of the former exceeds the latter by 8.5% and the former has more superior families in amount than the latter.