Effects of Light and Autotoxicity on the Reproduction of Bidens pilosa L.: From Laboratory to the Field

Ming-Tung Hsueh,Chihhao Fan,Wen-Lian Chang,Hsiao-Feng Lo

doi:10.3390/agriculture10110555

Abstract

In Taiwan, the good agricultural practices for Bidens pilosa L. (Cobbler’s pegs) had been established due to its pharmacology application. However, the reproduction of this species that may cause phytotoxicity to the subsequent crops has not been investigated extensively. We hypothesized that both the phytotoxicity and canopy shading conditions that were altered by agricultural practices might affect its seed reproduction. Three experiments from laboratory, pot and field were conducted under different light treatments and residue application rates to evaluate the light requirement and phytotoxicity on the germination of Cobbler’s pegs. The results showed that the germination in the laboratory, dark treatments was higher than that of light treatment while it was inhibited in the darkness in the pot experiments (24% of the light treatments). Moreover, some seeds in the pot experiments germinated in the far-red light (FR) pretreated dark treatments. This observation indicated that the germination response of the investigated plant might be a very low fluence response (VLFR). Results also showed that the autotoxicity enhanced the germination reduction in the FR pretreated dark treatment while increasing the residues buried in the field. Accordingly, both autotoxicity and canopy shading may inhibit the reproduction of Cobbler’s pegs, but the application method needs further study.

Highlights

Bidens pilosa L. (Cobbler’s pegs), originally from South America [1], is a member of the Asteraceae family [2]
For the residue extract of 0 g dry weight (DW) mL−1, the highest seed germination percentage was found in the DL treatment, followed by far-red light (FR)-WL, WL, FR-DL and FRL treatments
For the effects of residue extract, the results indicated that seed germination showed more affected by residue extract than by light treatments

Summary

Introduction

Bidens pilosa L. (Cobbler’s pegs), originally from South America [1], is a member of the Asteraceae family [2]. (Cobbler’s pegs), originally from South America [1], is a member of the Asteraceae family [2] Seeds of this pant are black and ribbed with barbed awns that facilitate the dispersal through animals. Cobbler’s pegs has been reported to be highly invasive and may cause damage to many crops in China [5,6], Japan [7,8], Taiwan [9,10,11] and Thailand [12,13]. It was an edible herb with medicinal applications in many countries. It was a leaf vegetable as well as a traditional medicinal herb in many

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Discussion

Conclusion