Two experiments were conducted for effective practice use of extract residue of dwarf bamboo (Sasa veitchii (Carr.) Rehder) (ERDB). In Exp.1, chemical composition, nutritive value and palatability of the ERDB were measured. In addition, the ERDB was ensiled together with no substrate (intact), 10% rice bran (RB) or 10% polished rice bran (PRB) to examine the fermentative quality, nutritive value and palatability. They were allocated 3 treatments, i.e. control, RB and PRB. In Exp.2, feed utilization, behaviour and health condition were investigated on goats fed ERDB ensiled with no substrate (intact), 10% RB or 10% PRB. Three does were assigned to four treatments: control (lucerne hay cube: HC), ERDBS-HC (80% HC+20% ERDB silage in a DM basis), RB-HC (80% HC+20% RB silage) and PRB-HC (80% HC+20% PRB silage), respectively.

Exp.1: The crude protein and crude fat of the ERDB were 10.4 and 7.4%, respectively, which were more than twofold of those of rice straw. Crude fiber was also higher in the ERDB than in rice straw, showing a value of 45.7%. Although chemical composition was very different between ERDB and rice straw, total digestible nutrients (TDN) of the former was 45.5%, which approximated that of the latter. However, it was verified that the ERDB was less palatable than rice straw and imported grass hays for goats and cows. The Flieg scores of the RB and PRB silages were significantly higher than that of the control (P<0.05). All silages got over 62 points, indicating that they had good quality. Palatability was significantly increased in the RB and PRB silages comparing the ERDB and control (P<0.05).

Exp.2: There were no significant differences in DM, CP and TDN intakes per metabolic body size, daily maintenance behaviour of the goats, and roughage value index among the control, ERDB-HC, RB-HC and PRB-HC groups. Blood constituents exclusive to the total bilirubin concentration did not differ among the treatments, and all haematological and blood biochemical parameters were within standard range.

In conclusion, the addition of RB and PRB to the ERDB improved fermentative quality, nutritive value and palatability, though ensiling of only ERDB was feasible. However, it was suggested that RB and PRB silages should be offered to ruminants in combination with other feedstuff in feeding, because both silages contained more than 7% crude fat. It was also concluded that the feed utilization and health condition of goats were not influenced by substituting RB or PRB silage for 20% (DM basis) of ordinary ration (HC). Therefore, both RB and PRB silages can be used as feed for ruminants.

Poaceae plants, such as silver grass or reed, are commonly used in weed mulch farming. In the Nishi-Awa area of Japan, which was designated as Globally Important Agricultural Heritage Systems (GIAHS) in 2018, farmers have traditionally been using silver grass for mulch farming. However, Japanese knotweed (Fallopia japonica) has been used solely for traditional eggplant cultivation. It is unclear why the farmers use Japanese knotweed for eggplant cultivation only. Therefore, we investigated the effects of Japanese knotweed mulching on eggplant cultivation to identify its effects on yield and eggplant quality.

Field experiments were conducted in 2016 and 2017 in the field center of Shizuoka University, Japan. The cultivar ‘Senryo nigou’ was used for every test. Egg plants were cultivated in plastic pots (diameter 30cm). We compared the Japanese knotweed mulching, silver grass mulching and no grass mulching farming (control). We investigated the transition of soil moisture, soil temperature, and plant height, date of flowering and fruiting, plant weight, yield (number, size weight of fruits), and quality of fruits (hardness, sugar content, anthocyanin content) of eggplants.

When there is little irrigation, soil moisture content was higher with Japanese knotweed mulching than with silver grass mulching and the control. Both Japanese knotweed and silver grass had good effect on reducing the temperature difference between days and nights. Neither Japanese knotweed nor silver grass had any effect on plant growth and yield of eggplant compared with the control. Compared with mulching with silver grass and the control, mulching with Japanese knotweed had a good effect on the quality of eggplant fruits, such as softening of the pericarp and increasing the sugar content of fruits. We suppose effect of soil moisture, soil temperature and allelochemicals of Japanese knotweed as a factor.