Co-application of compost or inorganic NPK fertilizer with biochar influences soil quality,grain yield and net income of rice

Most agricultural soils in sub-Saharan Africa are degraded, compromising the grain yield of rice and farmers return on investment. A 3-year field study was undertaken to explore the effect of the application of compost or inorganic NPK fertilizer applied alone or in combination with biochar on soil quality, grain yield of rice and net income. The five treatments were laid out using a randomized complete block design with four replications. The treatments were applied to supply approximately 75 kg N ha^–1. The best fertilizer input was compost+biochar which resulted in the greatest improvement in soil physico-chemical properties by reducing bulk density and increasing porosity and moisture retention, organic matter content, percent nitrogen, available phosphorus and cation exchange capacity. Apart from treatment with inorganic fertilizer alone, treated soils showed a decrease in pH. Bacterial and fungal counts and basal respiration decreased in soils in the following order: compost+biochar>compost only>inorganic NPK fertilizer+biochar>inorganic NPK fertilizer>control. The increase in pooled grain yield and net income in response to treatment followed the order: compost+biochar>NPK+biochar>NPK>compost>control. The findings suggest that the use of compost or NPK alone might improve soil quality and increase grain yield and net income, but it is greatly recommended to co-apply these fertilisers with biochar.     

Bentonite-humic acid improves soil organic carbon,microbial biomass,enzyme activities and grain quality in a sandy soil cropped to maize (Zea mays L.) in a semi-arid region

A bentonite-humic acid (B-HA) mixture added to degraded soils may improve soil physical and hydraulic properties, due to effects such as improved soil structure and increased water and nutrient retention, but its effect on soil physicochemical and biological properties, and grain quality is largely unknown.  The effect of B-HA, added at 30 Mg ha⁻¹, was studied at 1, 3, 5 and 7 years after its addition to a degraded sandy soil in a semi-arid region of China.  The addition of B-HA significantly increased water-filled pore space and soil organic carbon, especially at 3 to 5 years after its soil addition to the soil.  Amending the sandy soil with B-HA also increased the content of microbial biomass (MB)-carbon, -nitrogen and -phosphorus, and the activities of urease, invertase, catalase and alkaline phosphatase.  The significant effect of maize (Zea mays L.) growth stage on soil MB and enzyme activities accounted for 58 and 84% of their total variation, respectively.  In comparison, B-HA accounted for 8% of the total variability for each of the same two variables.  B-HA significantly enhanced soil properties and the uptake of N and P by maize in semi-arid areas.  The use of B-HA product would be an effective management strategy to reclaim degraded sandy soils and foster sustainable agriculture production in northeast China and regions of the world with similar soils and climate.     

农产品质量安全科研检测单位的劳务派遣用工管理

受人员编制限制,人力资源相对不足制约了农产品质量安全科研检测单位的发展。劳务派遣作为一种新型用工形式,一定程度上解决了农产品质量安全科研检测单位的人力资源配置问题。文章对农产品质量安全科研检测单位劳务派遣用工管理进行解析,分析存在的问题,并提出一些对策,以期对农产品质量安全科研检测单位的劳务派遣运用有所启示。     

蔬菜废弃物还田量及配施菌剂对土壤腐殖质组成的影响

为了促进蔬菜废弃物资源化还田,在室内模拟不同量[全量:每亩(667 m2)1.8 t,半量:每亩0.9 t]番茄秸秆和甘蓝叶残体还田,并设置添加菌剂(秸秆腐熟剂、农用酵素)和未添加菌剂处理,测定还田后7、14、21、28、35 d的土壤温度、pH、电导率、有机碳、养分含量以及腐殖质各组分含量,探究蔬菜废弃物还田量及配施菌剂对土壤理化性质和腐殖质组成的影响.结果 表明:各还田处理的土壤pH值呈先降低后增加趋势,其中配施菌剂处理的pH值变化幅度较小.蔬菜废弃物还田后7 d各处理的有机碳含量均迅速增加,增加范围为0.55～1.73 g·kg-1.与未施菌剂还田相比,还田35 d后番茄秸秆添加酵素全量还田处理的土壤全氮、碱解氮和速效钾含量分别增加了14.49％、9.30％和5.61％,甘蓝叶残体添加酵素全量还田处理的有效磷含量增幅最大,达到34.98％.在还田处理期间,番茄秸秆在第21 d的土壤水溶性物质含量达到最大,而甘蓝叶残体还田处理则是在第7 d上升到最大值,并且甘蓝叶残体各还田处理的土壤水溶性物质含量整体比番茄秸秆还田处理高.蔬菜废弃物配施酵素全量还田能够有效促进土壤腐殖质和胡敏酸含量增加,且两种蔬菜废弃物还田处理的土壤腐殖化程度均在还田第7d达到最大.综合比较而言,蔬菜废弃物配施酵素全量还田在提高秸秆资源化利用效率、降低还田成本方面效果最佳,更适宜推广应用.     

3个草莓品种在广西南宁市露地种植表现及品质特性

为筛选出适宜广西南宁地区露地栽培的草莓良种,引进‘京藏香’、‘京桃香’、‘红颜’3个草莓品种并进行试种和调查分析。结果表明,‘京藏香’、‘京桃香’、‘红颜’在露地栽培条件下物候期与‘甜查理’较接近,果实可溶性固形物含量都在10.5%以上,果实大小适中,平均单株产量在0.211 kg以上,平均单位面积产量在18990 kg/hm²以上。这些草莓品种产量较高,果实品质优良,抗性中等或偏弱,在做好水肥管理和病虫害综合防治的情况下可作为优良品种进行推广。     

木薯农艺性状及品质对不同海拔梯度的响应

为了探究木薯农艺性状及块根品质对不同海拔梯度的响应,进而明确海拔梯度变化对木薯生长的影响。以木薯品种‘SC205’、‘GR4’为材料,于800~1600 m的海拔上种植。同海拔木薯的株高、茎粗、主茎高和落叶高度随时间不断增加而增加,但同时间段,随海拔升高呈降低趋势,2个品种在8—10月生长最快,11月生长相对缓慢,到12月生长基本停止;随海拔梯度升高,同一木薯品种块根品质呈上升趋势,除粗纤维含量外,其他均差异达极显著;同海拔不同木薯品种间,除粗纤维含量外差异显著;块根品质含量最高多出现在海拔1400 m,最低在海拔1000 m或800 m。不同海拔下,海拔800 m、1000 m木薯生长旺盛,海拔1400 m块根品质相对较好,生产上应根据用途选择适宜的木薯种植海拔。     

西北地区提升农产品供给质量制约因素研究

本研究基于西北地区农产品供给质量评价指标体系,采用指标达标率、偏离度、制约度等变量对西北地区农产品供给质量提升的制约因子进行诊断。数据表明,西北五省区23个基础指标均存在不达标情况,宁夏、青海农产品供给质量有接近一半的指标达标率低于50%。深入研究制约因子发现,主体指标按制约度从高到低排序依次为营销、加工、种植和流通,基础指标制约因子主要分为3类,制约度由高到低依次为收入、供给主体和创新能力。据此,本研究针对性提出对策建议,以期为探索西北地区农产品供给质量提升路径提供借鉴。     

施镁量对土壤供镁及烤烟生长发育和产质量的影响

为明确福建‘翠碧一号’烤烟适宜的施镁量以及施镁对烟田土壤供镁的影响,采用田间试验研究不同施镁量对烟田不同时期土壤供镁、烟株物质积累和烤后烟叶产质量的影响。结果表明,随施镁量的增加,土壤交换性镁浓度上升,不同时期土壤供镁能力与施镁量表现为显著的直线线性相关关系。终采时烟株不同部位叶片镁含量和积累量也均与施镁量存在显著的直线线性相关关系。施镁处理的均价、产值、上等烟比例和上中等烟比例分别比不施镁处理提高了6.39%~11.67%、6.13%~14.63%、18.43%~31.46%和5.36%~8.96%。随施镁量的增加烤后烟叶总钾含量呈下降趋势。综合烤后不同部位烟叶感官评吸质量以施镁（以MgO计）量在19.5 kg/hm²处理最好,其次为39 kg/hm²处理;产值以施镁58.5 kg/hm²处理最高。施镁量对烟株生物量积累和烤后烟叶产量的影响规律性不明显。综合福建植烟土壤交换性镁含量的实际情况,以及土壤供镁、烟株物质积累和烤后烟叶质量,认为福建‘翠碧一号’烤烟生产中,施镁（以MgO计）量以19.5~39 kg/hm²为宜,既能保证土壤正常供镁和镁营养的相对平衡,又能满足烟株对镁营养的需求,提高烤后烟叶质量。     

生物有机肥配施硅钙钾镁肥对西瓜产量、品质及土壤养分的影响

为科学减少化肥用量,改善土壤结构和环境,研究生物有机肥和硅钙钾镁肥对作物生长和改善土壤养分方面的作用,以‘L600’小果型西瓜为研究对象,设置生物有机肥配施硅钙钾镁肥并减少底肥化肥用量等4个处理,以常规施肥作为对照,研究上述肥料对西瓜产量、品质及土壤养分的影响。结果表明：生物有机肥配施硅钙钾镁肥与常规施肥相比,产量提高8.05%,心糖含量提高13.08%,边糖含量提高5.77%,维生素C含量提高18.57% ,总酸含量降低31.25%、硝酸盐含量下降18.22%。两种肥料对改善土壤环境具有积极作用,土壤pH、有效磷、速效钾含量对比常规施肥明显升高。在此条件下减少底肥化肥施用,能够保证西瓜产量和品质,是一种有效的减量施肥方法。     

山东烟叶感官质量与物理化学指标相关性研究

为了分析山东烟叶感官质量与物理化学指标的相关性,解析烟叶品质的化学基础和物理标识,采集典型中部和上部烟叶样品,通过感官质量评价、理化检测和数理统计分析,并对叶位、地域分布差异进行了比较。结果表明,山东上中部烟叶物理指标总体适宜,化学成分总体相对协调,感官质量总体较好,地域分布差异显著。中部叶在适宜范围内指标的比例高于上部叶。感官质量评价指标与化学成分和物理指标进行典型相关分析,分别得到3对和两对显著性典型变量,对典型变量影响较大的感官质量评价指标为杂气、余味、香气质,影响较大的化学成分指标为还原糖、总糖、两糖比、氯、总氮和烟碱,物理指标为叶宽、单叶重、叶片厚度,叶面密度和叶长。其中,杂气指标与钾氯比呈显著正相关,与氯、半纤维素呈显著负相关;余味与钙、氮碱比、钾氯比、叶宽、含梗率呈显著正相关,与淀粉、烟碱、钠、硫、氯、两糖比、叶片厚度、叶面密度呈显著负相关;香气质与钙、钾氯比、叶宽、含梗率呈显著正相关,与总氮、烟碱、钠、氯、两糖比、叶片厚度、叶面密度呈显著负相关。今后可采取相关措施进行调控,为产区烟叶质量提升提供理论参考。