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141.
不同木屑颗粒度对工厂化压块香菇生长的影响 总被引:1,自引:0,他引:1
以香菇(Lentinula edodes)工厂化生产品种沪香F2为供试菌株,以香菇生产常用配方(78%木屑,20%麸皮,2%石膏)为基础培养料,以菌丝生长速度、子实体产量、单菇重、出菇期、生物学效率以及菇型等为筛选指标,考察不同木屑颗粒度配比对工厂化压块条件下香菇生产的影响。结果表明:颗粒度组合M3(K1∶1.5mm以下,K2∶1.5~3.0mm,K3∶3.0~8.0mm;K1∶K2∶K3=1∶1∶1)的菌丝生长速度最快[(5.2±0.8)mm/d],单菇重最大[(27.1±1.0)g],产量较高[(178.7±3.6)g],菇型好,第一潮菇生物转化率可达到40.8%,生产周期可控制在100d以内,适合于在工厂化条件下应用。 相似文献
142.
An economically based evaluation index for perennial and short‐term ryegrasses in New Zealand dairy farm systems
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D. F. Chapman J. R. Bryant M. E. Olayemi G. R. Edwards B. S. Thorrold W. H. McMillan G. A. Kerr G. Judson T. Cookson A. Moorhead M. Norriss 《Grass and Forage Science》2017,72(1):1-21
Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs (Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs ($ ha?1 calculated as change in operating profit divided by unit change of the trait) for additional DM produced in different seasons of the year in four regions. The EV of early spring DM was consistently high across all regions, whereas EV for late spring DM was moderate to low. Genotype × environment analysis revealed significant reranking of DM yield among ryegrass cultivars across regions. Hence, separate performance values (PVs) were calculated for two mega‐environments and then combined with the corresponding season and region EV to calculate the overall EV for twenty‐three perennial ryegrass and fifteen short‐term ryegrass cultivars. The difference in operating profit between the highest ranked and lowest ranked perennial ryegrass cultivar ranged from $556 ha?1 to $863 ha?1 year?1 depending on region. For short‐term ryegrasses used for winter feed, the corresponding range was $394 to $478 ha?1 year?1. Using PV for DM yield, it was estimated that plant improvement in perennial ryegrass has added $12–$18 ha?1 year?1 (depending on region) operating profit on dairy farms since the mid‐1960s. 相似文献
143.
Glutamine synthetase (GS) plays a central role in plant nitrogen (N) metabolism, which improves crops grain protein content. A pot experiment in field condition was carried out to evaluate GS expression and activity, and grain protein content in high (Wanmai16) and low grain protein (Loumai24) wheat cultivars under two N levels (0.05 and 0.15 g N kg−1 soil). High nitrogen (HN) resulted in significant increases in GS1 and GS2 expression at 10 days after anthesis (DAA), and higher GS activity during the entire grain filling stage. HN also significantly increased yield, grain protein content and protein fraction (except for glutenin of Luomai24) in two wheat cultivars, which indicated that it increased grain yield and protein content by improving nitrogen metabolism. Wanmai16 showed higher grain protein content, gliadin and glutenin content, and had higher expression level of GS2 both in flag leaves and grains at early grain filling stage. However, Luomai24 had greater yield and higher expression level of GS1. The difference expression of GS2 and GS1 genes indicates they had various contributions to the accumulation of protein and starch in wheat grains, respectively. The results suggest that GS2 would be serving as a potential breeding target for improving wheat quality. 相似文献
144.
James L. Smith 《Asia Pacific viewpoint》2017,58(1):99-111
This article is a discussion of the “discourse on the unthinkable” surrounding potential future democratic engagements with rivers as non‐human persons or natural objects. In the context of the Asia–Pacific region, this article suggests that the developments in material philosophy entitled “new materialism” are essential tools in the reconceptualisation of rivers as democratic entities but that local socio‐historical conditions must also be taken into the account. In order to make its case, the article not only surveys the context for considering rivers as non‐human persons in a juridical context but also discusses the new material context that assists modern democracies in the renegotiation of the demos that forms the body politic of democracy – often in the face of neoliberal exploitation and a legacy of extremes in instrumentalism. The article argues that the incorporation of water in the democratic project of enfranchisement is an essential exercise born of many Western beliefs and ideals but articulated uniquely at a regional and national level. 相似文献
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