有机肥对酿酒葡萄土壤微生物、酶活性及产量的影响

为明确施用不同有机肥对土壤有机质、酶活性和微生物以及酿酒葡萄产量的影响,采用田间小区设计,以5 a生赤霞珠酿酒葡萄为试验材料,研究不同有机肥对土层0～20、20～40 cm和40～60 cm中土壤有机质、酶活性和微生物的影响。以不施用有机肥为对照(CK),设置沼渣(BR)、羊粪有机肥(SMOF)、牛粪有机肥(CMOF)、猪粪有机肥(PMOF)、牛粪+沼渣有机肥(CMOF+BR)5个处理进行大田试验。结果表明:不同有机肥施用后与CK相比,土壤有机质增加6.79%～44.97%,土壤微生物碳增加19.78%～91.53%,微生物氮增加2.22倍～3.93倍,碱性磷酸酶增加57.78%～512.55%,过氧化氢酶增加53.45%～240.48%,增产15.12%～46.89%。不同土层施用牛粪有机肥相对于其它有机肥处理土壤有机质含量增长8.49%～33.29%;土壤中微生物碳、氮的含量分别增加5.30%～42.46%和6.12%～49.65%;碱性磷酸酶增大8.01%～184.63%,过氧化氢酶增加5.14%～84.27%,脲酶提高25.58%～410.70%,蔗糖酶升高6.00%～107.65%;微生物总数增多5.99%～56.56%。施用牛粪有机肥相比较其它有机肥增产7.08%～27.60%。说明在宁夏地区施用有机肥可有效提高土壤有机质的含量,增加微生物的数量,增加土壤酶活性,促进酿酒葡萄的生长发育,提高产量,其中以牛粪效果最为显著。     

河套灌区盐渍化土壤玉米水氮耦合效应

为了探求适用于盐渍化地区的节水、施肥优化模式，采用大田试验，以玉米为研究对象，选取了轻度和中度两种盐分土壤，设置了10种不同水、氮处理，建立不同盐分土壤玉米产量与灌水量及施氮量之间的回归模型并对其进行了分析，研究不同盐分土壤水、氮用量对玉米产量的影响。结果表明：在轻度和中度盐分土壤条件下，灌水和施氮对玉米均有增产效应，水、氮交互作用为正效应，水分的作用大于施氮的作用。通过边际效应分析可知，轻度和中度盐分土壤施氮肥的增产速率没有明显差异，轻度盐分土壤灌水的增产效率明显高于中度盐分土壤。轻度和中度盐分土壤玉米最高产量分别为13 581 kg·hm^-2和11 115 kg·hm^-2，对应的水、氮配比均为灌水编码为0.77（全生育期灌水量2 250 m³·hm^-2），施氮编码为0.69（总施氮量225 kg·hm^-2）。通过模型寻优，得到轻度和中度盐分土壤种植玉米的最佳水、氮配比方案均为全生育期灌水量为1 900.95~2 389.08m³·hm^-2，总施氮量为174.04~240.7 kg·hm^-2。优化方案的水、氮用量分别比当地灌水量（2 925 m³·hm^-2）节水18.2%~35%, 施氮量（325 kg·hm^-2）节肥26.0%~46.4%。优化范围包含了轻度和中度盐分的最高产量水、氮用量，产量与当地产量基本一致，符合当地灌水施肥要求。但从维持目前玉米产量和长期盐碱地改良的角度看，建议中度盐化土壤应选取水、氮优化范围中中等偏上灌水量和中等偏下的施肥量，以便于从根本上降低土壤盐分背景值，便于长期产量的提高；轻度盐分土壤选取优化范围适中的水、氮用量。     

Effect of transferring lignocellulose-degrading bacteria from termite to rumen fluid of sheep on in vitro gas production,fermentation parameters,microbial populations and enzyme activity

The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.     

多花黄精不同种源种实形态性状遗传变异研究

旨在阐明多花黄精种实形态性状在种源水平上的遗传变异规律,为多花黄精优良种源选择提供理论依据。以栽植在同质栽培园的18个多花黄精种源为材料,比较了不同种源多花黄精浆果、种子的纵径、横径、侧径等形态性状,以及单果重和种子千粒重等性状的差异。多花黄精种实形态性状及其单果鲜重和种子千粒重在不同种源间均存在着极显著差异;多花黄精浆果形态性状两两之间存在极显著正相关关系,种子形态性状两两之间也存在显著或极显著正相关关系,但绝大多数浆果形态性状与种子形态性状之间的相关性不显著;多花黄精种实形态性状在种源水平上不存在明显的地理变异模式;多花黄精种子形态性状在种源水平上的广义遗传力达到强度遗传范围,能比较稳定地遗传。可以考虑利用种子千粒重这一指标作为多花黄精优良种源选择的间接指标。     

表型组学在水稻研究中的应用

水稻作为重要粮食作物,其重要农艺性状的功能基因组研究是植物生物学研究的热点。植物基因型、表型和环境三者构成了遗传学研究的铁三角。随着高通量测序技术的快速发展,基因型的研究更加简单快速。然而表型研究严重滞后于基因型研究。目前传统的表型信息的获取存在所需劳动量巨大、成本高,所获取表型数据受人工主观因素影响大等诸多难题。高通量表型组学可无损、高通量、精准获取表型信息,对解决以上难题具有关键作用。本文对表型组学在水稻中的研究应用情况进行整理,为今后水稻基因组学和表型组学等多学科相结合的现代研究手段提供理论支撑。     

关于提高大豆种植生产效益的栽培技术要点

大豆作为一种农作物，种植过程中容易受到土壤、水分、气候、湿度、温度、病虫害等多方面因 素的影响，这些因素都是人为很难改变的。大豆栽培技术主要是通过对这些影响因素的改变来降低 这些问题的影响，以此来提高大豆的产量和种植户的经济效益。     

基于能值分析京郊蔬菜不同生产经营方式的生态经济可持续性评价

利用能值理论和经济投入、产出分析方法,对北京郊区农户常规种植、企业常规种植和企业有机种植3种大棚蔬菜的生态经济可持续性进行研究。结果表明:在能值评价方面,企业有机种植模式能值年总投入为6.81×10~(16)sej/hm~2,低于农户常规种植模式(1.19×10~(17)sej/hm~2)和企业常规种植模式(8.53×10~(16)sej/hm~2);能值投资率为44.20,分别是农户常规种植和企业常规种植模式的2.41和3.81;环境负载率为2.14,低于农户常规种植模式(3.76)与企业常规种植模式(6.29);可持续发展指数为0.48,高于农户常规种植模式的0.28和企业常规种植模式的0.19。在经济方面,企业有机种植模式的利润(1.45×10~6元/hm~2)高于农户常规种植模式(3.34×10~5元/hm~2)和企业常规种植模式(负利润)。综合能值与经济2个方面,企业有机种植模式是京郊大棚蔬菜的3种模式中生态经济可持续性最优的模式。     

Effects of egg stocking density on egg hatchability,larval quality and water quality for pinfish,Lagodon rhomboides,and pigfish,Orthopristis chrysoptera

Pinfish (Lagodon rhomboides Linnaeus) and pigfish (Orthopristis chrysoptera L.) are relatively new, cultured species commonly used as marine baitfish in the south‐eastern United States and currently have no defined protocols for egg incubation. Thus, experiments were conducted to determine efficient egg stocking densities during static and flow‐through incubation that yielded higher quality larvae. Eggs of each species were incubated statically at 250, 500, 1000 and 2000 eggs L^?1, and after incubation, egg hatching success, larval survival to first feeding, larval morphometrics and water quality were assessed. Stocking densities above 250 eggs L^?1 led to significant reductions in pinfish hatching success and water quality degradation, evident from decreased dissolved oxygen and pH levels and increased nitrogenous wastes. Increased stocking densities for pigfish also resulted in significant water quality degradation, although hatching success was unaffected up to a density of 1000 eggs L^?1. A high flow‐through water exchange rate of 2000% daily resulted in significant reductions in nitrogenous wastes and greater stability in dissolved oxygen and pH levels during incubation when compared to static treatments of the same egg density. Additionally, the high exchange rate of 2000% was critical in maintaining high hatching success and larval survival to first feeding at stocking densities of 1000 eggs L^?1 for pinfish and up to 4000 eggs L^?1 for pigfish. No clear patterns in larval morphometrics were observed among stocking densities. Static incubation densities of 250 and 1000 eggs L^?1 are recommended for pinfish and pigfish, respectively.