Allelopathic influence of some fruit tree leaf extracts on germination and seedling development of different weeds and vegetable crops

Abstract

Allelopathy is an important mechanism by which plants release allelochemicals. This study aimed to evaluate and compare the allelopathic effect of extracts of fruit tree leaves (orange, mango, jabuticaba and guava trees) on the germination and seedling development of different weeds (morning glory and beggartick) and vegetable crops (lettuce and cabbage). The FGC and G were evaluated. After germination, SDM and SL were measured. In general, first germination counting (FGC) and G (germination) were decreased for all species conducted with the allelopathic extracts in relation to the control. Mango extract reduced the FGC of morning glory in 20 p.p.m. The G of beggartick reduced to 0%, while cabbage and lettuce germination was not affected. The highest reduction on FGC was observed in lettuce using jabuticaba extract, usinf 9 p.p.m, compared to the control. The extracts reduced the G of morning glory and beggartick, respectively, in between 5 and 11 p.p. Jabuticaba extract reduced significantly the G of morning glory and beggartick. The development of morning glory and beggartick was negatively affected by allelopathic extracts. The G of morning glory and beggartick is affected by the jabuticaba extract. The development of cabbage seedling was affected when all extracts were used and guava extract affected the length of cabbage seedlings. Mango extract has potential to control morning glory and beggartick in established lettuce and cabbage fields. Mango, orange, jabuticaba and guava extracts have the potential to control weeds on lettuce established fields. Guava extract is not indicated to control weeds on cabbage cultivated fields.