灯盏花不同部位水浸提液对4种作物的化感效应分析

【目的】从化感作用角度筛选适宜与灯盏花进行间套轮作的农作物，为解决灯盏花连作障碍，建立合理的灯盏花间套轮作体系提供参考依据。【方法】采用水提法制备灯盏花根、茎、叶浸提液，每种浸提液设3个浓度梯度（0.05、0.10和0.15 g/mL），以蒸馏水为对照，研究灯盏花不同部位浸提液对辣椒（Capsicum annuum）、玉米（Zea mays）、水稻（Oryza sativa）和青菜（Brassica chinensis）的化感效应。【结果】灯盏花根、茎、叶浸提液对辣椒、玉米、水稻种子萌发和幼苗生长均有不同程度的抑制效应，综合化感效应强度随着水浸液浓度的增加而增强。灯盏花叶浸提液对辣椒种子发芽指数呈低促高抑的双重效应。0.15 g/mL根浸提液处理下，辣椒、玉米、水稻和青菜的幼苗根长分别较对照显著下降75.78%、77.79%、82.24%和69.75%（P<0.05，下同）。低浓度根浸提液可显著增加青菜幼苗苗长，0.05 g/mL处理的青菜苗长较对照显著增长60.34%。4种作物对灯盏花化感作用的敏感性程度为辣椒>水稻>玉米>青菜。灯盏花各部位水浸液对4种作物的化感作用强弱整体表现为地上部>地下部。【结论】青菜和玉米较适宜进入灯盏花轮作体系中，以缓解灯盏花连作障碍，该结论与实际种植情况相符。

Allelopathic effect of extracts from different parts of Erigeron breviscapus (Vant.) Hand-Mazz on four kinds of crops

【Objective】 The crops which were suitable for intercropping or rotating with Erigeron breviscapus(Vant.) Hand-Mazz were screened based on allelopathy to provide theoretical basis for establishing efficient model of E. breviscapus intercropping or rotation system.【Method】 Extraction solutions of roots, stems and leaves of E. breviscapus were obtained through water extraction method. Three concentration gradients(0.05, 0.10 and 0.15 g/mL) were set for each extract. The allelopathic effects of extraction solution from different parts of E. breviscapus on Capsicum annuum, Zea mays, Oryza sativa and Brassica chinensis were studied with distilled water as the control.【Result】 The aqueous extracts from the roots, stems and leaves of E. breviscapus had strong allelopathic effects on seed germination and seedling growth of the four crops, and the effect intensity increased with the increase of the concentration of aqueous extracts. The aqueous extracts from leaves of E. breviscapus had a dual effect of low promotion and high inhibition on C. annuum seed germination index. Under the treatment of 0.15 g/mL root extract, the seedling root length of C. annuum, Z. mays, O. sativa and B. chinensis significantly decreased by 75.78%, 77.79%, 82.24% and 69.75% respectively compared with the control(P<0.05, the same below). Low concentration(0.05 g/mL) water extracts of E. breviscapus significantly increased the seedling length, seedling length of B. chinensis treated with 0.05 g/mL root extract increased significantly by 60.34% compared with the control. The allelopathic sensitivity of four crops to E. breviscapus was as follows:C. annuum>O. sativa> Z. mays>B.chinensis. Allelopathic effect of aqueous extracts of E. breviscapus on different parts were ordered as aboveground>underground.【Conclusion】 B. chinensis and C. annuum are more suitable for the rotation system of E. breviscapus to alleviate the continuous cropping obstacle of E. breviscapus. The result is in accordance with the actual plantation situation.