Islam M.R.,National Grassland Research Institute |
Ishida M.,National Grassland Research Institute |
Ando S.,National Grassland Research Institute |
Nishida T.,National Grassland Research Institute |
Yoshida N.,Saitama Livestock Research Center
Animal Feed Science and Technology | Year: 2011
The study investigated the suitability of stage of maturity and botanical fractions of whole crop rice (WCR) to predict yield and nutritive value of ensiled WCR for dairy cows. Eight varieties of WCR (i.e., Akichikara, Fukuhibiki, Habataki, Hamasari, Hokuriku 168, Kusanami, Tamakei 96, Yumetoiro) were harvested at four stages of maturity (i.e., 10, 22, 34, 45 days after flowering [DAF]) and ensiled. Dry matter (DM) yield at each harvest was determined. Silage samples were fractionated into four botanical fractions being: leaf blade, leaf sheath, stem and head. Silage samples were also analyzed for chemical composition, fermentation characteristics, in situ DM and N disappearance. Metabolizable energy (ME) and metabolizable protein (MP) content of samples were estimated according to Terada et al. (1988) and AFRC (1993), respectively. Relationships between maturity or proportions of botanical fractions and contents of WCR silage in terms of DM, ME and MP, and their yields, were estimated by correlation and regression analysis. Stage of maturity was positively related (P<0.001) to ME content (R2=0.46; y=4.53+0.08X) and MP content (R2=0.56; y=22.26+0.76X), and DM yield (R2=0.63; y=9.21+0.12X), ME yield (R2=0.68, y=36931+1708X) and MP yield (R2=0.72, y=161.0+14.15X) of WCR. Proportion of leaf was negatively related to yields and nutritive value of ensiled WCR, whilst proportion of head was positively related (P<0.05 to <0.001). Proportion of head was best related to the ME content (R2=0.72; y=3.26+0.009X), MP content (R2=0.72; y=12.31+0.079X), and DM yield (R2=0.41; y=9.02+0.009X), ME yield (R2=0.76, y=19494+165.5X), and MP yield (R2=0.75, y=34.37+1.32X) of WCR. Results suggest that to optimize yield and nutritive value, WCR should be ensiled within 40 DAF and the proportion of head should be equal to or more than 500g per kgDM of WCR silage. Stage of maturity and proportion of head of WCR predict yields of DM, ME and MP of WCR, and their contents, in WCR silage with acceptable accuracy. However, these relationships need to be validated using large data sets and in vivo studies. © 2010 Elsevier B.V.
Kurokawa S.,National Grassland Research Institute |
Kurokawa S.,Japan National Agricultural Research Center |
Shibaike H.,Japan National Institute for Agro - Environmental Sciences |
Yoshimura Y.,National Grassland Research Institute
Japan Agricultural Research Quarterly | Year: 2011
Thirty-nine herbarium specimens of Abutilon theophrasti collected between 1883 and 2000 were examined for chloroplast DNA (cpDNA) analysis in order to examine the invasion process by cpDNA haplotype B, which was mixed in imported grain and accidentally introduced into Japan. By using nested PCR, all of the 39 specimen materials prepared were determined to be either of two haplotypes (the total numbers of haplotype A and B were 21 and 18, respectively). The first specimen of haplotype A was the oldest of all the samples; it had been collected in Yamagata in 1883. The collection times of the haplotype A specimens ranged evenly over the surveyed period. The first specimen of haplotype B was also old; it had been collected in Tokyo in 1893. Compared to haplotype A, the collection times of haplotype B concentrated on the 1960s and 1970s. The frequency of haplotype B has significantly increased after 1946 (before 1945: 27.8%; after 1946: 61.9%). These results may suggest that the accidental introduction of haplotype B has been increasing after World War II, reflecting the increase in the amount of grain imports.
Shoji A.,National Grassland Research Institute |
Hayashi H.,National Grassland Research Institute |
Kohyama K.,National Grassland Research Institute |
Sasaki H.,National Grassland Research Institute
Grassland Science | Year: 2011
We investigated plant community attributes and selected soil characteristics of a Japanese boreal semi-natural grassland among day-grazed (24h), night-grazed and ungrazed sites in Akkeshi, eastern Hokkaido. We also evaluated the effects of horse grazing on plant species richness and the population of Iris setosa, a hygrophilous target species for conservation. Species richness and iris dominance were the highest and community height was the lowest at the day-grazed site; however, plant coverage and light intensity at ground level did not differ significantly among the sites. Soil aeration and water permeability of the surface soil were the lowest at the day-grazed site. Logistic regression analyses suggested direct and/or indirect positive effects of grazing on the occurrence probability of nine species. Species richness was negatively correlated with community height, soil aeration and water permeability of the surface soil and positively correlated with bulk density and soil hardness. Iris dominance was negatively correlated with aeration and water permeability and positively correlated with surface soil bulk density and volumetric water content. Iris dominance was also positively correlated with species richness. Canonical correspondence analyses demonstrated different species composition among the sites that mainly segregated with grazing intensity, soil bulk density, surface soil aeration and community height. Our results showed that all-day horse grazing in a boreal semi-natural grassland modifies surface soil characteristics and increases plant species richness and dominance of I.setosa. © 2011 The Authors. Grassland Science © 2011 Japanese Society of Grassland Science.