Participation of Allelopathy in Injury due to Continuous Cropping of Asparagus (Asparagus officinalis L.) in Alluvial Soil

Abstract

Replanting of asparagus (Asparagus officinalis L.) often results in lower yields and extensive damage of young plants. One of the causes is considered allelopathy. In this study, we examined the participation of allelopathy on injury by continuous cropping of asparagus in alluvial soil. The presence of strong allelochemical substances, which have the growth-inhibitory activity, was detected by bioassay of rhizosphere soil around asparagus. This growth-inhibitory activity was not attributed to salt accumulation, pH fluctuation, or inorganic nutrient imbalance in the rhizosphere soil. Asparagus foliage incorporated into the soil did not demonstrate a close relation to the growth inhibition or decreased yield of asparagus. However, strong growthinhibitory activity was demonstrated in the storage roots of asparagus. It is assumed that an allelochemical is exuded from the storage roots and is one of the causes of unsuccessful continuous cropping of asparagus.

Distribution of Rutin and Protodioscin in Different Tissue Parts of Asparagus (Asparagus officinalis L.)

“…Al-though the rutin content of asparagus was high in the aboveground parts (Motoki et al, 2012b), 3.008 and 3.242 mg · g -1 DW of rutin was measured in the storage roots (brown and epidermis), amounts equivalent to levels in the tip spear. As asparagus stocks are growing, the color of its storage roots changes from white to yellow and brown (S. Motoki, unpublished data), and its growth-inhibitory activity increases (Motoki et al, 2006). According to the results of this study, the rutin content in the white, yellow, and brown storage roots were 0.243, 1.116 and 3.008 mg · g -1 DW, respectively; rutin content increases as asparagus stocks age.…”

“…When storage roots of asparagus are left in the soil, inhibitory substances are released that cause problems with replanting (Motoki et al, 2006;Yeasmin et al, 2013Yeasmin et al, , 2014Young and Chou, 1985). Some asparagus fields in Japan were spoiled because effective measures to solve the replant problem were not implemented.…”

“…Fresh asparagus spears commonly discarded if their length is out of specifications, also contain a large amount of rutin, and spears that have not been harvested at the optimum time may be useful components or resources of rutin (Motoki et al, 2012a). Unlike cladophylls, strong growthinhibitory activity was observed in storage roots (Motoki et al, 2006).…”

“…However, the nonusable parts of asparagus with weak growth-inhibitory activity can be used as mineral elements or reused as fertilizer components for the following year. Furthermore, if the cladophylls and the storage roots, or nonusable parts of asparagus, can be used as useful component resources, this will not only reduce the amount of waste, or plant residues generated during production, but also help to solve the problem of replanting failure (Motoki et al, 2006), which will significantly influence production settings.…”

Production Trend and Cropping System of Asparagus in China

“…The outline of production and main cultivars was published in Japanese commercial magazine (Motoki et al 2014) and book (Motoki 2016). So the authors try to provide detail and recent trend of Chinese asparagus and the possibility to improve the cultivars for adaptation to Chinese environment because Dr. Zhang, one of authors, is a member of the Jiangxi Academy of Agricultural Sciences, center of asparagus research in China.…”