不同水稻苗床调理剂对机插秧秧苗素质的影响

以宁粳4号为试验材料,通过塑盘育秧方式,研究了3种水稻苗床调理剂对机插秧秧苗素质的影响。结果表明:"海陵"和"诚信"水稻苗床调理剂与对照相比,能显著降低苗高、加快出叶速度、缩小最大叶长、扩大最大叶宽,增加茎基宽、根系重量、根冠比、盘结力和发根能力;而"春泉"水稻苗床调理剂明显增加苗高、最大叶长、最大叶宽、茎基宽和地上部重量,加快出叶速度,对根冠比、盘结力和发根能力影响不大。海陵和诚信水稻苗床调理剂能提高机插秧秧苗素质,延长秧龄,值得推广应用。     

BGA土壤调理剂对木薯产量的影响研究初报

以木薯品种华南205为试验材料,研究了施用BGA土壤调理剂对红壤旱地木薯产量的影响。结果表明:在不同处理中,以一次性施用2400 kg/hm2BGA土壤调理剂处理的产量最高。施用1200～2400 kg/hm2BGA土壤调理剂处理的产量高于施用300 kg/hm2复合肥处理的产量。     

农牧交错带是我国牛业突围崛起的战略支撑点

在新西兰乳品冲击下,我国农业生态系统存在着潜伏的危机;在美国规模化养牛模式误导下,我国养牛业陷入误区。由此,提出我国大农业生态系统需要依靠养牛做为支柱,以肉奶两用牛为战略支撑,实现乳肉皆优,肉乳双收,并把农牧交错带确立为我国牛业突围、崛起的战略支撑点。     

贵州岩溶山区不同类型人工草地杂草发生程度调查

选取贵州省具有代表性的8个地区(市)20个县、市岩溶山区不同类型人工草地进行杂草调查,侵害草地的杂草隶属于26科79种。通过调查统计分析,不同类型人工草地杂草分布达"一般分布"的占到88%,人工草地的杂草分布比较广泛;杂草出现频率10%～45%,人工草地的杂草发生程度比较普遍。初步掌握发生草地杂草的种类及其规律,为进一步提高草地利用效率提供了借鉴依据。     

Evaluation of associative effects on ruminal digestion kinetics between pasture and grains using in vitro gas production method

In vitro gas production (GP) method was used to investigate associative effects on ruminal digestion when grains (corn or barley) were supplemented to spring pasture and autumn pasture. Pasture (75%) was incubated with 25% corn or barley and gas production was monitored up to 96 h. After incubation, the residues were used to determine dry matter and organic matter digestibility (DMD and OMD). Gas production parameters were analyzed by applying a single exponential equation. Organic matter effective degradability (OMED) was determined from GP parameters and OMD. The positive associative effects on the rate of GP, DMD, OMD and OMED were observed when spring pasture was incubated with corn. However, similar effects were not observed in a barley mixture. However, for autumn pasture, both corn and barley mixtures showed positive associative effects on rate of GP, OMD and OMED. The results of this study indicated that supplementation of corn would be better than barley for spring pasture with high water‐soluble carbohydrate contents, whereas both grain supplementations were effective to obtain positive associative effects on the rate of GP and OMED for autumn pasture with high cell wall content.     

European outbreaks of atypical myopathy in grazing equids (2006-2009): spatiotemporal distribution, history and clinical features

Reasons for performing study: Improved understanding of the epidemiology of atypical myopathy (AM) will help to define the environmental factors that permit or support the causal agent(s) to exert toxicity. Objectives: This European survey of AM aimed to describe spatiotemporal distribution, survival, clinical signs, circumstances in which AM develops and its different expressions between countries and over time. Methods: The spatiotemporal distribution, history and clinical features of AM cases reported to the Atypical Myopathy Alert Group from 2006 to 2009 were described. Comparisons of data from the most severely affected countries and from the large outbreaks were made with Fisher's exact and Welch's tests with Bonferroni correction. Results: Of 600 suspected cases, 354 met the diagnostic criteria for confirmed or highly probable AM. The largest outbreaks occurred during the autumns of 2006 and 2009 in Belgium, France and Germany. For the first time, donkeys, zebras and old horses were affected, and clinical signs such as gastrointestinal impaction, diarrhoea, penile prolapse, buccal ulceration and renal dysfunction were observed. Affected horses spent >6 h/day on pastures that almost always contained or were surrounded by trees. The latency period was estimated at up to 4 days. Overall survival rate was 26%. Although differences between countries in affected breeds, body condition, horse management and pasture characteristics were recognised, the common presenting clinical signs and mortality were similar between countries. Conclusions and potential relevance: This study describes new data on case details, history and clinical course of AM that is of preventive, diagnostic and therapeutic value. However, the true impact of the findings of this study on the development of or severity of AM should be tested with case–control studies.     

不同氮素肥料对混播草地牧草生产性能的影响

分别利用沼液和尿素进行混播草地施肥试验,结果表明,混播草地中牧草的产量受到氮肥种类、施氮水平和环境温度的限制。在环境温度较高时,施入尿素含量越高,牧草生长速率较快,产量越高;而当秋季温度较低时,豆科牧草长势旺盛,因此氮肥对混播牧草产量的影响相对较小;同时,由于沼液对土壤的培肥作用较好,以大量施入沼液的牧草长势较好,产量较高。     

南方立筒仓应用移动空调控温储存玉米研究

对立筒仓的玉米应用移动空调进行控温储存试验,试验表明通过空调间歇性控温能确保玉米安全度夏储存安全,降低粮食保管费用。     

Carbon and nitrogen stocks in a Brazilian clayey Oxisol: 13-year effects of integrated crop–livestock management systems

Integrated crop–livestock management systems (ICLS) have been increasingly recommended in Brazilian agroecosystems. However, knowledge of their effect on soil organic carbon (SOC) and total nitrogen (TN) concentrations and stocks is still limited. The study was undertaken to evaluate the effects of ICLS under two tillage and fertilization regimes on SOC and TN concentrations and stocks in the 0–30 cm soil layer, in comparison with continuous crops or pasture. The following soil management systems were studied: continuous pasture; continuous crop; 4 years’ crop followed by 4 years’ pasture and vice-versa. The adjacent native Cerrado area was used as a control. Under the rotation and continuous crop systems there were two levels of soil tillage (conventional and no-tillage) and fertility (maintenance and corrective fertility). The stock calculations were done using the equivalent soil mass approach. The land use systems had a significant effect on the concentrations of SOC and TN in the soil, but no effect was observed for the soil tillage and fertilizer regimes. For these two latter, some significant discrepancies appeared in the distribution of SOC and TN concentrations in the 0–30 cm layer. Carbon storage was 60.87 Mg ha⁻¹ under Cerrado, and ranged from 52.21 Mg ha⁻¹ under the ICLS rotation to 59.89 Mg ha⁻¹ with continuous cropping. The decrease in SOC stocks was approximately 8.5 and 7.5 Mg ha⁻¹, or 14 and 12%, for continuous pasture and ICLS respectively. No-tillage for 10 years after the conversion of conventional tillage to no-tillage under the continuous crop system, and 13 years of conventional tillage in continuous cropping did not result in significant changes in SOC stocks. The SOC and TN stocks in surface layers, using the equivalent soil mass approach rather than the equivalent depth, stress the differences induced by the calculation method. As soil compaction is the principal feature of variability of stocks determinations, the thickness should be avoid in these types of studies.     

岷县高寒牧区多年生豆科牧草引种试验初报

2001年,从甘肃农业大学草业学院和甘肃草原总站引种了16种多年生豆科牧草,在岷县麻子川乡璇窝草原站种羊场试种,对其物候期、生物学特征、抗逆性和经济性状进行了2年(2002-2003年)的观察与研究.结果表明,除野生黄花苜蓿Medicago falcate,小冠花Coronilla varia,白三叶Trifolium repens外的其他13种牧草均可在岷县高寒牧区种植;13种牧草中,岷山红三叶Trifolium pratense,WL-232HQ苜蓿,8920MF多叶苜蓿优于其他品种.