添加烟草废弃物对堆肥腐熟度及抑制线虫作用的影响

以鸡粪和小麦秸秆为堆肥原料,在C/N为25与含水率为60%的条件下采用静态好氧堆肥工艺,研究了不添加烟草废弃物(CK)和在初始期(A)、高温期(B)、一次发酵完成(C)和陈化腐熟后(D)添加1.5%(干重质量比)烟草废弃物对堆体发酵温度、总碳(TC)、发芽率指数(GI)和根结线虫校正死亡率的影响。结果表明:添加烟草废弃物会降低堆肥发酵过程的温度,影响微生物对有机物料的分解,不利于堆肥物料的快速腐熟。CK处理的GI值在19d时已超过腐熟度标准80%的要求,而添加烟草的处理A、B和C的GI值在19d时仍低于80%;在处理45d时处理CK、A、B、C和D的GI值分别为102.6%、95.6%、85.8%、83.4%和70.4%;这表明烟草废弃物对植物生长具有一定的抑制作用。烟草废弃物和处理C与D堆肥产品浸出液的线虫校正致死率都达到了100%;而处理CK、A和B堆肥产品浸出液的线虫校正致死率依次为44.4%、28.2%和70.0%;这表明烟草废弃物经过发酵的时间越长,对线虫的抑制效果就越差;在堆肥一次发酵完成后添加烟草废弃物,不但可避免其对堆肥进程和植物生长的不利影响,而且经过陈化腐熟后仍能保持对根结线虫的抑制作用。     

蚕沙好氧堆肥腐熟度指标研究

堆肥腐熟度是衡量堆肥反应进程和堆肥产品质量的主要参数,为了探索蚕沙堆肥腐熟度的快速评价体 系,以蚕沙为主要堆肥材料,以蘑菇渣和谷壳作为调理剂,采用静态好氧堆肥模式进行3 种堆肥处理,研究蚕沙堆肥处 理过程中理化、生物学性状的变化规律,并对各指标作相关性分析。结果表明,当发芽指数逸80%,C/N 和T值分别降至 12.07和0.76,堆肥颜色呈黑色、无气味、温度降至常温时,蚕沙堆肥达到充分腐熟。因此,蚕沙堆肥处理过程中的堆肥颜 色、气味、温度、C/N、T 值及发芽指数与蚕沙好氧堆肥腐熟度紧密相关,可作为蚕沙好氧堆肥腐熟度快速评价指标。     

华北冬小麦开花及成熟期变化特征分析

利用华北平原59个农业气象观测站1981—2010年冬小麦生育期资料,分析了该区域冬小麦在气候变暖背景下开花期和成熟期的变化趋势特征。研究结果表明：近30年来,华北平原冬小麦开花期和成熟期均发生了明显变化。相对1980s而言,1990s开花期普遍提前2～5 d,成熟期提前1～6 d左右,2000s开花期则一般提前3～9 d,成熟期提前1～7 d左右。因此,随着年代推进,华北平原冬小麦开花期和成熟期提前趋势在进一步加剧。相对1980s而言,1990s生育期等值线普遍北移,而2000s等值线进一步北移的趋势更加明显。研究发现,3—5月月平均气温升高是开花期和成熟期提前的一个重要影响因素。     

大黄鱼一年两次性成熟发育特征的研究

选择春季产过卵的2^ 龄大黄鱼Pseudosciaena crocea(Richardson)在网箱中进行隔离培育，秋季从中挑选当年再次性成熟的亲鱼进行人工催产，比较春、秋两季的人工繁殖与仔、稚鱼培育效果，并定期观察卵巢及卵细胞的发育情况。实验表明，春季产过卵的同一批大黄鱼雌鱼，有72．1％的个体当年秋季可再次成熟，有58．8％的个体可以再次产卵，证实养殖大黄鱼具有一年“两熟”的性腺发育特征。     

Prevalence and different characteristics of two serotypes of Streptococcus parauberis isolated from the farmed olive flounder, Paralichthys olivaceus (Temminck and Schlegel), in Korea

The prevalence of two serotypes of Streptococcus parauberis isolated from the olive flounder, Paralichthys olivaceus, was evaluated in a total of 29 isolates between 2003 and 2010 in Korea. Streptococcus parauberis isolates were divided into two serologically distinct types (serotype 1 and serotype 2), except for one strain (S1091), using an agglutination assay with rabbit antiserum, and serotype 1 was identified as the dominant type (24 of 29 isolates) in this study. To identify the characteristics of the two serotypes of S. parauberis, we conducted a biochemical test using the API 20 Strep kit, a transmission electron microscopy (TEM) assay, sequence analysis of 16S‐23S rRNA intergenic spacer region (ISR) and a pathogenicity test. In TEM, both serotypes possessed polysaccharide capsule layers around the cell surface when bacterial cells were treated with a homologous serotype of rabbit antiserum. However, we were unable to discriminate serotype‐specific biochemical characteristics and genetic characteristics of 16S‐23S rRNA ISR between the two serotypes. In the pathogenicity test, the serotype 1 strains induced significantly higher mortality than the serotype 2 strains in olive flounder when experimentally inoculated via the intraperitoneal route.     

Density effects on length at maturity of walleye pollock <Emphasis Type="Italic">Theragra chalcogramma</Emphasis> off the pacific coast of northern Japan in the 1990s

To determine how stock abundance fluctuations of walleye pollock Theragra chalcogramma are related to variations in reproductive characteristics, the length at 50% maturity of the fish sampled off the Pacific coast of northern Japan from 1990 to 1999 was examined. In both sexes, the fish density increased, and the body length of age-3-5 fish decreased, but the condition factor and the age at 50% maturity showed no clear trend during this period. Male length at 50% maturity decreased, while value for females showed no clear trend. In both sexes, significant negative correlations were found between density index (combined age-3-5) and each body length at age-3-5. Significant positive correlations were seen between each body length at age-3-5 and length at 50% maturity in males. Positive correlation between body length at age-5 and length at 50% maturity was significant in females from 1990 to 1999, except for the samples in 1998. We suggest that the fish density might affect the length at maturity in males and possibly also in females.     

基于BMV特征的西瓜成熟度无损检测方法

针对西瓜成熟度无损测定的难度较大这一问题,提出了一种基于音频响应频带幅值向量（BMV）特征的西瓜成熟度无损检测方法。搭建了一套简单的音频采集平台,检验了BMV音频特征与西瓜成熟度的相关性,并与4种已用于西瓜无损检测的音频特征进行了比较;测定了不同打击力度对音频响应和BMV的影响;使用PNN算法对2个品种西瓜的BMV样本进行了成熟度检测。试验结果表明：经过音频特征间的比较,BMV与西瓜成熟度相关性最高,并且打击力度对特征的影响较小,整套算法对2个品种的成熟度检测准确度较高。     

Reproductive season and female maturity size of coconut crab <Emphasis Type="Italic">Birgus latro</Emphasis> on Hatoma Island,southern Japan

Information about reproductive season, size at sexual maturity and size-dependent reproductive potentials is important for efficient resource management. Such information is necessary to determine seasonal closures and minimum legal size limits. To conserve resources of coconut crab Birgus latro, which are in danger of extinction due to excessive exploitation, their reproductive season, female size at functional maturity and relationship between female size and reproductive potentials were investigated. The reproductive season started in early June and ended late August, and females with higher reproductive potentials showed a tendency to spawn early in the reproductive season. The prohibition of exploiting the resources during the reproductive season, especially early in the season, would be appropriate for sustainability of high reproductive outputs. Fifty percent of investigated females matured functionally at 24.5-mm thoracic length (TL). However, the size at which all females reached functional maturity was 32.3 mm TL, and there was a wide variation in the size of functional maturity among individuals. We must determine minimum legal size by taking the variation into account to allow all individuals to mate at least once before they are caught, which may prevent serious depression in reproductive rate and genetic diversity.     

Distribution and spawning dynamics of capelin (Mallotus villosus) in Glacier Bay, Alaska: a cold water refugium

Pacific capelin (Mallotus villosus) populations declined dramatically in the Northeastern Pacific following ocean warming after the regime shift of 1977, but little is known about the cause of the decline or the functional relationships between capelin and their environment. We assessed the distribution and abundance of spawning, non‐spawning adult and larval capelin in Glacier Bay, an estuarine fjord system in southeastern Alaska. We used principal components analysis to analyze midwater trawl and beach seine data collected between 1999 and 2004 with respect to oceanographic data and other measures of physical habitat including proximity to tidewater glaciers and potential spawning habitat. Both spawning and non‐spawning adult Pacific capelin were more likely to occur in areas closest to tidewater glaciers, and those areas were distinguished by lower temperature, higher turbidity, higher dissolved oxygen and lower chlorophyll a levels when compared with other areas of the bay. The distribution of larval Pacific capelin was not sensitive to glacial influence. Pre‐spawning females collected farther from tidewater glaciers were at a lower maturity state than those sampled closer to tidewater glaciers, and the geographic variation in the onset of spawning is likely the result of differences in the marine habitat among sub‐areas of Glacier Bay. Proximity to cold water in Glacier Bay may have provided a refuge for capelin during the recent warm years in the Gulf of Alaska.     

梨新品种--华酥

‘华酥’为‘早酥’ב八云’种间杂交育成的早熟优质高产抗病梨新品种。果实成熟比早酥早 10～ 15d。果实圆形 ,单果质量 2 0 0～ 2 50g ,果皮黄绿色 ,果肉质细 ,酥脆多汁 ,酸甜适口 ,风味浓并具芳香 ,品质佳。早果高产 ,7年生树产量为 4 2 .5t/hm2 。高抗黑星病。