Replacing Soybean Meal with Alternative Protein Sources in Diets for Pond‐raised Hybrid Catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus

The present study investigated the replacement of soybean meal with combinations of two or three alternative protein sources in diets for pond‐raised hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. Alternative protein sources evaluated included cottonseed meal, distillers dried grains with solubles (DDGS), peanut meal, and porcine meat and bone meal (PMBM). Hybrid catfish fingerlings with a mean initial weight of 35 g/fish were stocked into 25 earthen ponds (0.04 ha) at a density of 14,826 fish/ha. Fish were fed once daily to apparent satiation for 166 d. No significant differences were observed for total diet fed, net yield, weight gain, survival, carcass yield, fillet yield, or fillet proximate composition among dietary treatments. Results show soybean meal may be completely replaced by combinations of cottonseed meal and one or two other alternative protein sources including DDGS, peanut meal, and PMBM in the diet without markedly affecting production and processing characteristics and fillet proximate composition of pond‐raised hybrid catfish. These alternative diets may be used during foodfish production when prices are favorable.     

果蔬型甜玉米新品种京科甜191的选育

京科甜191是以超甜玉米自交系T68为母本,自交系T6302为父本,通过杂交选育而成的果蔬型甜玉米品种。果穗筒型,穗长19.0 cm,穗粗5.3 cm,穗行数16~18行,行粒数36~38粒,粒行整齐。籽粒亮黄色,外观漂亮。平均每667 m2鲜果穗产量900 kg左右,出籽率约67.4%。鲜籽粒含粗蛋白2.98%,粗脂肪1.37%,总糖6.7%,口感甜脆清爽,皮薄无渣。播种至采收平均85.4 d(天),适宜京津冀及类似生态区种植。     

Effects of elevated CO2 concentration on bulbil germination and early seedling growth in Chinese yam under different air temperatures

The present study investigated the effects of elevated carbon dioxide concentration ([CO₂]) and air temperature on the germination of seed bulbils and the seedling vigour of two Chinese yam lines. Plants were grown under two [CO₂] levels, ambient and elevated (ambient + 200 μmol mol^?1), and two mean air temperature regimes, 22.2 °C (ambient + 1.4 °C) and 25.6 °C (ambient + 5.2 °C). Elevated [CO₂] did not affect bulbil germination under both air temperature regimes. During the early growth stage, the dry weight (DW) of leaves, vines, shoots, roots, belowground parts (roots + tubers) and whole plants were higher under elevated [CO₂] than ambient [CO₂] for both lines under the low- and high-temperature regimes. The values of vigour indexes (index I = germination % × seedling length and index II = germination % × seedling DW) were also higher under elevated [CO₂] than ambient [CO₂] for both lines. These results indicated that Chinese yam seedlings respond positively to elevated [CO₂] during the early growth stage. The above:belowground DW ratios were lower under elevated [CO₂] than ambient [CO₂] in seedlings with very small new tubers for both yam lines, indicating that elevated [CO₂] strongly affected the root growth in the early growth stage. The DWs of post-treatment seed bulbils were higher in the elevated [CO₂] under both air temperature regimes. The results showed that Chinese yam used a smaller amount of the reserves in seed bulbils under elevated [CO₂] than under ambient [CO₂].     

铅(Pb2+)和镉(Cd2+)对火炬树种子萌发及幼苗生长的影响

【目的】研究不同浓度重金属铅(Pb^2+)和镉(Cd^2+)对火炬树Rhus typhina种子萌发及幼苗生长的影响,探索火炬树对重金属铅、镉胁迫的耐受程度及机理。【方法】采用培养皿滤纸发芽法,分别用不同浓度Pb^2+(300、600、900、1200、1500 mmol/L)、Cd^2+(140、280、420、560、700 mmol/L)溶液处理火炬树种子,测定种子发芽率、发芽指数、幼苗胚根长和茎长、硫代巴比妥酸(TBARS)含量、可溶性蛋白含量、超氧化物歧化酶(SOD)活性及过氧化物酶(POD)活性。【结果】与对照相比,不同浓度Pb^2+、Cd^2+均对火炬树种子的发芽率、发芽指数和幼苗生长有抑制作用,但低浓度Pb^2+可促进根长和芽长的伸长。随着Pb^2+和Cd^2+溶液浓度的增加,幼苗叶片中SOD活性和可溶性蛋白含量表现为先增加后降低,POD活性和TBARS含量均逐渐升高。其中,Cd^2+浓度为700 mmol/L时,发芽率、发芽指数、芽长和SOD活性达到最低值,而TBARS含量最高;Pb^2+浓度为1500 mmol/L时,根长达到最低值,POD活性达到最高值;Pb^2+浓度为600 mmol/L时,可溶性蛋白含量最高。【结论】Pb^2+浓度为300 mmol/L时会抑制火炬树种子萌发,但会促进幼苗生长,其余浓度Pb^2+、Cd^2+胁迫下,火炬树种子与幼苗受到一定影响,但是均较好完成了萌发与幼苗生长,并表现出多种积极的适应性特征,未出现无根苗现象,火炬树较其他木本植物对铅、镉2种重金属表现出更强的耐性。本试验结果可为今后选用火炬树作为重金属污染土壤的植物修复材料提供理论参考。     

氮磷钾用量对小麦冠层不同层次光截获和干物质分配的影响

为明确不同氮、磷、钾用量对小麦冠层不同层次光截获和干物质分配的影响，以济麦22为供试材料，设置F0（不施肥）、F1（N 180 kg·hm^-2，P₂O₅ 75 kg·hm^-2，K₂O 60 kg·hm^-2）、F2（N 225 kg·hm^-2，P₂O₅ 120 kg·hm^-2，K₂O 105 kg·hm^-2）和F3（N 270 kg·hm^-2，P₂O₅ 165 kg·hm^-2，K₂O 105 kg·hm^-2）4个施肥量处理，比较分析开花后不同氮、磷、钾用量对小麦叶面积指数、冠层不同层次光截获特性和成熟期干物质分配的影响。结果表明，F1处理下叶面积指数显著高于F0处理，而与F2和F3处理间无显著差异；开花后15 d，F1处理下小麦冠层不同层次及总PAR截获率和截获量均显著高于F0处理，而与F2和F3处理间无显著差异。F1处理下成熟期干物质在小麦冠层不同层次营养器官中的分配量、籽粒中的分配量及总干物质积累量显著高于F0处理，而与F2和F3处理间无显著差异。成熟期干物质在小麦冠层不同层次营养器官和籽粒中的分配量以及总干物质积累量与冠层上层（顶部至株高2/3）、中层（株高2/3至株高1/3）和总PAR截获率均呈显著正相关。F1处理（N 180 kg·hm^-2，P₂O₅ 75 kg·hm^-2，K₂O 60 kg·hm^-2）为本试验条件下的最优处理。     

饲料中无机元素分析方法研究进展

饲料中所含的无机元素对动物生长具有重要意义。在饲料中过量添加无机元素会导致环境污染问题,也会通过食物链最终危害消费者的身体健康,因此,对饲料产品中的无机元素进行检测和动态监控尤为重要。综述了近年来饲料中无机元素含量检测主要应用的前处理方法及其含量检测技术,分析了不同前处理方法和含量检测技术的优点和不足,以期为饲料中无机元素分析方法的科学、合理应用提供参考。     

Inhibitory Effects of AURKB Gene on Apoptosis and Cancer Cell Growth in HCT 116 Cells

[Objectives]To explore the inhibitory effect of AURKB gene in apoptosis and cancer cell growth in HCT 116 cells.[Methods]The in vitro cytology studies were carr...     

春大棚基质化栽培辣椒品种比较试验

为了提高甜辣椒规模化、产业化生产的竞争力,进一步提高产量、效益和品质,加快甜辣椒栽培管理技术的推广和应用,特引进7个辣椒新品种并采用基质化栽培管理模式进行对比研究。通过对辣椒生长势、品质和产量的比较分析,结果表明:夏驰、国福908、海迈604表现突出,具有个大、肉厚、口感好、品质优、连续坐果性好等特点,而且产量、效益较高,抗病性强,适合设施基质化栽培生产,有很好的推广价值。     

Effect of dietary calcium or phosphorus deficiency on bone development and related calcium or phosphorus metabolic utilization parameters of broilers from 22 to 42 days of age

This experiment was conducted to investigate the effect of dietary calcium (Ca) or phosphorus (P) deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study, which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age. A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design, and fed the normal control and Ca- or P-deficient diets from 1 to 21 days of age. At 22 days of age, the broilers were further fed the normal control diet (0.90% Ca+0.35% non-phytate P (NPP)), the P-deficient diet (0.90% Ca+0.18% NPP), the Ca-deficient diet (0.30% Ca+0.35% NPP) or the Ca and P-deficient diet (0.30% Ca+0.18% NPP), respectively. The results showed that dietary Ca or P deficiency decreased (P<0.05) tibia bone mineral density (BMD), bone breaking strength (BBS), ash content, tibia ash Ca content and serum P content on days 28 and 42, but increased (P<0.05) tibia alkaline phosphatase (ALP) activity of broilers on day 42 compared with the control group. Furthermore, the broilers fed the P-deficient diet had the lowest (P<0.05) tibia BMD, BBS, ash content, serum P content and the highest (P<0.05) serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets. The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency, followed by dietary Ca deficiency or Ca and P-deficiency; dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.