凉水自然保护区森林演替序列土壤水溶性碳水化合物质量分数特征1）

为探讨不同森林植被类型对土壤中碳水化合物的影响,以凉水自然保护区原始红松针阔混交林和阔叶次生林为对象,对土壤碳水化合物进行研究。结果表明：随着土层深度的增加,两种植被类型下土壤中碳水化合物质量分数都有递减的趋势。在0～10 cm和＞10～20 cm土层中,阔叶次生林土壤碳水化合物质量分数显著高于原始红松针阔混交林土壤。在2种碳水化合物提取方式下,热水（100℃）提取的碳水化合物质量分数显著高于常温（25℃）提取的（ p＜0．05）,且都是随着土层深度增加,碳水化合物质量分数降低。浸提液在波长254 nm和280 nm下的吸收值与相应提取的碳水化合物质量分数都呈显著正相关。     

叶面补施水溶肥料对旱区小麦生长的影响

在洛阳市洛龙区农场进行的叶面喷施磷酸二氢钾、黄腐酸、黄腐酸＋含腐植酸水溶肥料与有机水溶肥料对干旱地区小麦生理指标及产量的影响试验表明,喷施水溶性肥料增强了小麦叶片的SOD和POD活性,提高了叶片的叶绿素含量,降低了叶片的相对电导率及丙二醛含量,以喷施黄腐酸＋含腐植酸效果最好,小麦折合产量7683.0 kg/hm2,较喷清水处理增产624.0 kg/hm2,增产率8.8%。     

不同型号酵母浸粉及补糖对异养微藻生长的影响

微藻在FM802、FM902和FM760 3种不同型号的安琪酵母浸粉配制的培养基中进行异养生长,培养条件为28℃、200 r/min的摇床中进行暗培养,培养过程中补糖1次,每隔24 h取样20 mL进行分析检测。结果表明:补糖情况下,型号为FM802的酵母浸粉比FM902培养微藻的效果稍好,FM760培养效果稍差;补糖有利于微藻干物质重的增加;在pH值为4.2~5.5的培养基中,微藻仍能快速生长。     

广西花生品种（系）苗期生长耐旱性及相关生理特性研究

花生苗期生长受干旱影响最大,且干旱是广西花生生产上重要的限制因素。选择广西主推及新育成的花生品种（系）共11个,在人工防雨棚下进行土培盆栽试验,以正常淋水（2d供水1次）为对照,以人工控水（10d供水1次）作为干旱胁迫处理,反复干旱胁迫30d时,测定花生苗期的主茎高尧侧枝长、生物量以及叶绿素、可溶性糖、丙二醛尧脯氨酸含量,计算花生苗期生长生理受抑制程度及生长耐旱隶属函数值。结果表明,在干旱胁迫下,各参试花生品种的主茎高、侧枝长和生物量均受到不同程度的抑制,其中桂花819的生长受抑制程度最轻。从各参试品种苗期耐旱隶属函数值排名可知,桂花819的苗期生长耐旱性最强,其次是桂花红166、桂花21和桂花26;大多数品种的叶绿素、可溶性糖、丙二醛尧脯氨酸含量在干旱胁迫下增加,少数花生品种表现出降低趋势,且苗期耐旱品种桂花819的叶绿素和脯氨酸含量比对照的增加量最大,丙二醛和可溶性糖含量增加量也较大。     

Replacement of fishmeal in diets for Australian silver perch Bidyanus bidyanus (Mitchell). II. Effects of cooking on digestibility of a practical diet containing different starch products

Abstract The interactive effects of cooking and starch type on the dry matter, gross energy and protein digestibility of diets fed to fingerling silver perch were examined. Nine experimental diets were made: a reference diet either uncooked or cooked, six other diets comprising uncooked reference diet supplemented with 30% uncooked or cooked wheat, maize or potato starch and one diet comprising uncooked reference diet supplemented with 15% pregelatinized maize starch. Cooking involved autoclaving at 121 °C for 15 min. The indirect method was used to calculate apparent digestibility coefficients, and chromic oxide (1%) was used as the inert indicator. Both ingredient type and cooking influenced dry matter and gross energy digestibility of diets. All diets had significantly different digestibility coefficients in the following order (from most to least digestible): reference > wheat > maize > potato, for both dry matter and gross energy. Cooking significantly increased the apparent digestibility of diets for both dry matter and gross energy. There was no significant effect of ingredient or cooking or their interaction on protein digestibility. Dry matter and energy digestibility of the diet containing pregelatinized maize starch were significantly higher than for diets containing cooked or uncooked starch products. Ingredient digestibility followed the same trend as diet digestibility. The results from this study indicate that the successful use of starch in practical diets for silver perch is dependent on the origin and processing of the starch. The significant benefits of cooking in the reference diet suggest that pelleted diets should be cooked (e.g. steam conditioned or extruded).     

Utilization of dietary starch and glucose tolerance in juvenile chinook salmon (Oncorhynchus tshawytscha) of different strains in seawater

Juvenile chinook salmon of three strains responded to inclusion of 28.7% of gelatinized starch in the diet with different degrees of reduction in growth rate and feed efficiency relative to control fish of the respective strains fed a low-starch, high-lipid diet of similar protein (46%) and estimated metabolizable energy content (16 mJ/kg). The productive protein value of the diet was not reduced to the same extent by the high intake of starch. Carcasses of fish fed the high-starch diet contained higher concentrations of protein and lower concentrations of lipid than control fish. The accumulation of liver glycogen in response to the high-starch diet differed among strains. Glucose tolerance curves also varied among strains but were poorly correlated with plasma concentrations of insulin. Tolerance to glucose loading was improved in fish previously fed the high-starch diet.     

钾硅肥配施对胡麻茎秆碳水化合物及抗倒性的影响

为明确钾硅肥施用对胡麻茎秆碳水化合物主要成分含量及抗倒伏特性的影响,探讨钾硅肥运筹调控胡麻茎秆抗倒伏能力的机制,选用裂区试验设计进行了研究,以两个品种为主处理,三个K2O钾肥用量(K0:不施钾;K1:52.5 kg/hm2;K2:105 kg/hm2)为副处理,两个SiO2硅肥用量(Si0:不施硅;Si1:90 kg/...     

Storage and Remobilization of Soluble Carbohydrates after Heading in Different Plant Parts of a Winter Wheat Cultivar

Abstract

Several types of water soluble carbohydrates (WSG) were traced into plant parts of a winter wheat (Triticum aestivum L.) cultivar from heading to physiological maturity. Field grown plants were harvested at intervals of a few days and divided into grain, chaff, leaf blades, leaf sheaths, rachis + peduncle and culm internodes. Leaf blades and sheath showed the peak of WSC contents at about anthesis. Culm internodes accumulated fructan and sucrose during the early grain-filling phase, from a week after anthesis until the milk-ripe stage, then remobilized them during late and final grain filling phases, from the milk-ripe stage until maturity. The amount of sucrose known as short-term storage WSC was higher than fructan known as long-term storage WSC in each internode throughout the grain-filling phase. Chaff showed a large amount of fructan and fructose before anthesis, although it did very little sucrose. A pattern of sucrose accumulation in chaff was very different from that of fructan, unlike the other parts. These patterns of changes in WSC contents in plant organs roughly corresponded with four grain-filling phases, the initial, early, late and final phases.     

在大肠杆菌中高效表达人粒-巨噬细胞集落刺激因子可溶性融合蛋白的研究

通过人粒－巨噬细胞集落刺激因子与疏氧还蛋白融合的形式，利用ＰＴｘＦｕｓ表达载体，高效地表达了其可溶性融合蛋白，该融合蛋白具有较高的热稳定性。     

Low-protein supplement increases protein retention and reduces the amounts of nitrogen and phosphorus wasted by rainbow trout fed on low-fat herring

The growth, food utilization and amounts of nitrogen and phosphorus lost into the water by rainbow trout (initial size 485 g) fed on low-fat Baltic herring and supplemented with a low-protein dry diet fed separately were studied in an 18-week net cage trial. Similarly to balancing protein and nonprotein energy in full diets, giving nonprotein energy in different feeds several hours apart improved the protein retention of low-fat herring to a level comparable to a commercially available dry diet control. The amounts of nitrogen and phosphorus lost into the water were also reduced to the same extent. The losses from the plain herring-feeding were twice as high. The improved protein retention and reduced nutrient losses were accompanied by 15–25% reductions in growth of the fish compared with the control dry diet. The growth of the fish fed on plain herring was 14% lower than the growth on the dry diet control.