el-Sayed W, Hurle K
Department of Weed Science, Institute of Phytomedicine, University of Hohenheim, D-70593 Stuttgart, Germany.
Meded Rijksuniv Gent Fak Landbouwkd Toegep Biol Wet. 2001;66(2b):775-89.
The purpose of the investigations was to determine the efficacy of different conidia concentrations of Phomopsis convolvulus Ormeno on different leaf stages of Convolvulus arvensis seedlings and regrowth potential of C. arvensis 25 days after inoculation. Furthermore, the potential of P. convolvulus on the growth of C. arvensis derived from different root lengths was studied. The results showed a great reduction in dry weight of above-ground biomass with more than 80% irrespective of the conidia concentration (1 x 10(6), 10(7) and 10(8) conidia/ml) on plants of the leaf stage 1-3 and 5-7 and gave more than 80% reduction of root biomass with an exception in case of 1 x 10(6) conidia/ml on plants of the leaf stage 9-11. Mortality was reached complete only with 1 x 10(8) conidia/ml on plants of the leaf stage 1-3. Regrowth potential of C. arvensis at more developed leaf stages was higher than at early leaf stages. Within the 3 categories of root lengths tested (5, 10 and 15 cm), the 1-3 leaf stage shoots showed the highest susceptibility to P. convolvulus. Obtained results illustrate that the application of P. convolvulus with 1 x 10(8) conidia/ml at the young leaf stage (1-3 leaf stage) on all treatments give a great reduction of biomass and adversely affects regeneration of the plants.
这些研究的目的是确定不同分生孢子浓度的旋花拟茎点霉（Phomopsis convolvulus Ormeno）对田旋花（Convolvulus arvensis）幼苗不同叶龄阶段的功效以及接种后25天田旋花的再生潜力。此外，还研究了旋花拟茎点霉对源自不同根长的田旋花生长的影响。结果表明，无论分生孢子浓度如何（1×10⁶、10⁷和10⁸个分生孢子/毫升），对于处于第1 - 3叶龄和第5 - 7叶龄阶段的植株，地上生物量干重大幅减少超过80%；对于处于第9 - 11叶龄阶段的植株，除了1×10⁶个分生孢子/毫升的情况外，根生物量减少超过80%。仅在第1 - 3叶龄阶段的植株上，使用1×10⁸个分生孢子/毫升时死亡率达到100%。田旋花在较发达叶龄阶段的再生潜力高于早期叶龄阶段。在所测试的3类根长（5厘米、10厘米和15厘米）中，第1 - 3叶龄阶段的地上部分对旋花拟茎点霉最敏感。所得结果表明，在所有处理中，于幼叶阶段（第1 - 3叶龄阶段）施用1×10⁸个分生孢子/毫升的旋花拟茎点霉会使生物量大幅减少，并对植株再生产生不利影响。
