氮素分期优化管理对冬小麦产量和籽粒品质的影响

采用田间试验,对氮素分期优化管理方法对小麦籽粒品质的影响进行了研究,以期为高产、优质、资源高效、环境保护等多重目标并重的养分资源优化管理提供理论依据.结果表明:氮素供应量最优的处理(冬小麦返青期氮素供应量即0～60 cm土壤Nmin+肥料氮为90 kg/hm2,拔节期追氮量即施用肥料氮30 kg/hm2)的冬小麦籽粒产量和其他氮素供应量处理没有显著差异;氮素供应量最优的处理冬小麦籽粒的粗蛋白和面筋含量显著低于在返青期和拔节期供氮量都高的处理(冬小麦返青期氮素供应量即0～60 cm土壤Nmin+肥料氮为150kg/hm2、拔节期追氮量即施用肥料氮90kg/hm2),但与其他处理相比差异不显著;以高产、资源高效和环境保护为前提的冬小麦氮肥分期优化施用量获得了最高产量的同时兼具较好的小麦籽粒品质.     

引进水稻品种(系)的产量、品质及RVA特性

对引进的5个水稻品种(系)进行了产量、品质及RVA特性研究,并对稻米的直链淀粉含量、RVA特征值及食味特性进行了相关分析,结果表明,稻米的直链淀粉含量与最高粘度呈极显著负相关,与消减值呈显著正相关,相关系数分别为r=-0.927和r=0.710,最高粘度与食味值呈显著正相关,相关系数为r=0.689。综合5个引进品种(系)产量、品质及RVA特性分析的结果可以看出：津稻1007增产最多(增产约58%),但食味品质最差;津原E28增产较多,食味品质与对照品种相当;津原45和津原43增产较多,食味品质稍逊于对照品种;津川1号有一定程度减产,但食味品质与对照品种相当,可作为优质稻育种中间材料加以利用。     

新型农村社会养老保险制度模式及其前瞻性问题分析

随着我国农村老龄化问题日益突出,农村老年人口养老、贫困问题成为制约农村社会建设的重要因素,作为农村基本社会福利保障制度的新型农村社会养老保险制度在解决农村老年人养老,缓解农村老年人贫困方面起到基础性作用。通过对新型农村社会养老保险制度模式的梳理,分析一些前瞻性问题,以期为新型农村社会养老保险制度的顺利推广,有效实现其预定目标提出相关政策建议选择。     

花后灌水对小麦籽粒品质性状及产量的影响

在池栽防雨条件下,研究了小麦花后不同灌水时期、不同灌水次数对籽粒产量及品质性状的影响。结果表明,在花前限量灌水条件下（135 mm）,花后灌水（45～90 mm）可显著提高小麦籽粒产量及蛋白质产量;虽然多数品质性状在花后不灌水（CK）条件下获得最大值,但灌1水未引起品质性状的明显变化;随灌水次数增加,各品质性状变劣     

不同氮肥运筹模式对冬小麦籽粒产量品质和氮肥利用率的影响

在高肥力条件下,研究了不同氮肥运筹模式对冬小麦籽粒产量、品质、氮肥利用率和土壤中硝态氮累积量的影响。结果表明,在本试验条件下,施用氮肥对籽粒产量、籽粒蛋白质含量和湿面筋含量无显著影响,而作为籽粒蛋白质质量指标的沉淀值、面团形成时间和面团稳定时间均明显改善。与分次施用（50%作底肥,50%作追肥）比较,拔节     

水氮配合对春小麦产量和品质的影响

在盆栽条件下，研究不同土壤水分和施氮量对春小麦产量和品质的影响。结果表明，当土壤相对含水量低于45％时，增施氮肥加重土壤水分胁迫，使籽粒产量、蛋白质产量以及籽粒粗蛋白含量均降低，而籽粒淀粉含量增加；当土壤相对含水量介于45％～75％时，增施氮肥能够缓解土壤干旱的不利影响，从而增加籽粒产量、蛋白质产量和籽粒粗蛋白含量，但降低籽粒淀粉含量，随着土壤水分状况的改善肥效提高；当土壤相时含水量高于75％时，增施氮肥虽然能提高籽粒粗蛋白含量，但以适量施用氮肥的籽粒产量和蛋白质产量最高。     

冬小麦品种籽粒物理品质性状及面粉品质性状的研究

以13个冬小麦品种(系)为材料，对其籽粒物理品质性状(包括千粒重、容重)和面粉品质性状(包括沉淀值、干、湿面筋含量)进行测定，并对各性状指标进行了相关分析和聚类分析，结果表明：容重与千粒重之间呈极显著正相关；干面筋与湿面筋间呈极显著正相关；沉淀值与干面筋呈极显著负相关；其他各指标间均无相关性。供试品种(系)大多数属于高容重、中千粒重、高沉淀值、中等面筋含量的品种。旨在为今后有计划的进行冬小麦品质改良提供信息和依据。     

氮素水平对藁城8901和山农1391籽粒品质的调控效应

选用强筋小麦品种藁城8901（GC8901）和弱筋小麦品种山农1391（SN1391）,在池栽条件下,分别施纯氮12、24和36 g m^-2,研究了氮素水平对小麦籽粒品质的影响。结果表明,氮素水平对2个类型小麦品种籽粒淀粉、蛋白质性状和加工品质有较大影响。与12 g m^-2处理相比,24 g m^-2处理明显提高籽粒支链淀粉含量,降低直链淀粉含量和直支比,促进淀粉积累,改善淀粉的糊化特性。当氮素水平增加至36 g m^-2时,籽粒的支链淀粉含量降低,直链淀粉含量提高,淀粉积累量降低。随氮素水平提高,GC8901籽粒清蛋白、球蛋白、谷蛋白、总蛋白含量和蛋白质产量提高,而醇溶蛋白含量降低。SN1391以24 g m^-2处理的醇溶蛋白、谷蛋白和总蛋白含量最低;随氮素水平提高球蛋白含量提高,而清蛋白含量降低。适量施氮能提高籽粒硬度,但过量施氮则使其降低。籽粒容重随氮素水平提高而降低。增施氮肥能提高GC8901面粉白度,但SN1391以12 g m^-2处理最高,24 g m^-2处理最低。氮素水平从12 g m^-2增加到24 g m^-2,GC8901面筋含量、质量提高,面团形成时间、稳定时间、拉伸面积和延伸度增加,这有利于提高强筋专用品质;SN1391面团形成时间和稳定时间显著降低,筋力变弱,拉伸面积减小,弱筋专用品质得以改善。当氮素水平增加至36 g m^-2时,2个品种加工品质有变劣的趋势。研究表明,改变淀粉、蛋白质及其各组分含量,是氮素水平影响小麦加工品质的重要途径。     

不同形态氮素对基质培番茄生育、产量及品质的影响

采用盆栽的方法,研究了不同形态氮素及不同配比对基质培番茄的生理代谢、生长发育、产量形成以及品质的影响。结果表明：氨态氮或酰胺态氮比例达到50：50时,植株生长正常,不曩根系活力和光合作用,叶片含水量正常。在秋冬茬可明显提高产量;在春夏茬可增加早期产量,总产量和单果重正常,并可延长果实的保鲜期。当氨态氮或酰胺态氮占营养液总氮量的75％时,植株生长受抑制。随着氨态氮或酰胺态氮比例的提高,叶片中全氮、全磷含量增加,果实中硝酸盐含量下降,还原糖、Vc含量上升,总酸含量不受影响。     

主栽金针菇品种中病毒的快速检测和鉴定

为了探索一种成本低、速度快、易操作、特异性强的dsRNA提取方法来检测金针菇中的病毒,并对目前主栽金针菇品种进行病毒的快速检测和鉴定。以各地主栽的金针菇品种为主要研究材料,采用试剂盒法和Redzol法2种方法检测dsRNA,将这2种方法进行比较,并通过反转录PCR和测序确定病毒种类。结果表明,试剂盒法和Redzol法均在主栽金针菇品种F-4889和F-4891菌丝体中检测到FvBV的病毒组分。与试剂盒法相比,Redzol法检测时间短,样品需求量小,易操作,成本较低,不需要繁琐的前期准备工作,适于实验室和大中型食用菌生产企业使用。Redzol法能从金针菇菌丝体中准确提取dsRNA病毒组分,并在主栽品种F-4889和F-4891菌丝体中成功检测到FvBV的病毒组分,为栽培生产、优化市场种质资源、育种选材等提供了理论依据。     

Effect of waterlogging stress on grain nutritional quality and pod yield of peanut (Arachis hypogaea L.)

To investigate the effects of waterlogging stress on grain nutritional quality and pod yield, peanut plants were waterlogged for 3 and 6 days at 7, 14, 21, 28, 35, 42, 49, 56 and 63 days after gynophores touched the ground in 2019 and 2020. Results revealed that compared with the control treatment, the oil and starch content in grain increased, while crude protein and soluble sugar content decreased under waterlogging. Waterlogging stress increased the unsaturated fatty acids content but decreased the saturated fatty acids, essential amino acids, non-essential amino acids and total amino acids content. In addition, waterlogging stress decreased the total pod number per plant by 6.78%–49.33%, 100-pod weight by 1.11%–14.08% and 100-grain weight by 1.85%–16.41%, which caused a 34.33%–55.90% reduction in pod yield per plant. After the gynophore touched the ground for 7 days, waterlogging had a greater negative effect on grain nutritional quality, and longer waterlogging duration led to greater yield reduction. In summary, waterlogging stress caused peanut yield reduction and grain quality deterioration.     

Leaf carbohydrates assimilation and metabolism affect seed yield of rapeseed with different waterlogging tolerance under the interactive effects of nitrogen and waterlogging

Waterlogging is a main factor causing rapeseed (Brassica napus L.) yield loss, and reasonable nitrogen (N) applications can compensate for this loss. To investigate the effects of N rates on seed yield of waterlogged rapeseed, the waterlogging-tolerant rapeseed variety ZS 9 and sensitive variety GH01 were waterlogged for 0 and 10 days with five leaves at the seedling stage under four N rates (0, 90, 180 and 270 kg/ha). Waterlogging significantly decreased seed yield, while N application can alleviate the yield loss. The yield decrease rate of waterlogged GH01 was greater than that of ZS 9 under the same N rate. During the seedling and bolting stage, the leaf photosynthetic rate (Pn) and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity increased, while activities of adenosine diphosphate glucose pyrophosphorylase (AGPase), sucrose synthase (SuSy) and sucrose phosphate synthase (SPS) decreased with more N under the same watering conditions. Compared to the plants without waterlogging, the leaf Pn and Rubisco activity, starch and sucrose contents of waterlogged rapeseed decreased at the two stages; activities of AGPase, SuSy and SPS of waterlogged rapeseed decreased at the seedling while increased at the bolting stage for both the two varieties. At the flowering stage, the Pn, the activities of Rubisco, AGPase, SuSy, SPS and contents of sucrose, starch increased with more N application for both ZS 9 and GH01. Compared to the plants without waterlogging, the Pn and Rubisco activity for waterlogged plants of the two varieties increased; the waterlogged plants of tolerant variety had higher activities of AGPase, SuSy and SPS, while those of sensitive variety was significantly lower. However, the decreased starch and sucrose content were found in both tolerant and sensitive varieties. The activities of AGPase, SuSy and SPS at flowering were highly positively correlated with yield under the interactive effects of N and waterlogging. These results suggested that the flowering stage is the most important stage that N had the positive regulation on waterlogged rapeseed growth. The carbohydrates translocation from leaves to seeds of the tolerant variety were enhanced after waterlogging, while that of the sensitive variety was still inhibited. This was the main reason for the difference in yield between the two waterlogged varieties.     

镉污染条件下不同形态氮肥对苋菜品质的影响

通过盆栽试验,研究了在镉污染的情况下不同种类的氮肥（硝酸铵、乙酸铵、尿素、硫酸铵、碳酸氢铵、氯化铵）对苋菜品质的影响,结果表明：在镉污染的蔬菜土壤上,Vc含量：硝酸铵〉尿素〉乙酸铵〉碳铵〉硫酸铵〉氯化铵;叶绿素含量：除硫酸铵稍差外,其他几个处理没有差异;可溶性糖的含量：硫酸铵〉乙酸铵〉尿素〉氯化铵〉硝酸铵〉碳铵;可溶性蛋白质的含量：尿素〉氯化铵,其他的比不施氮肥要差;粗纤维的含量：与对照基本没有差异;灰分的含量：施硝酸铵效果最好,其次是乙酸铵、尿素、碳铵。以各蔬菜品质含量为标准,施用碳酸氢铵、乙酸铵、尿素的效果比其他几种肥料要好。     

Crop yield and grain quality of emmer populations grown in central Italy, as affected by nitrogen fertilization

The increasing demand for traditional and natural foods has renewed the interest in hulled wheat species. Among these, Triticum dicoccum Schübler has survived in Italy only in a few hilly and mountainous areas of central and southern Italy. As a rule, emmer is cultivated in marginal areas with organic farming procedures that use very low N inputs, since this wild species is characterised by low yield, long and weak culms that easily lodge under windy conditions. Unfortunately, there is a lack of information on crop productivity and N effect for this crop. Research was carried out to study the effect of cultivation year (2004 and 2005), plant origin (Garfagnana, Leonessa and Molise) and N dressing (N₀, N₃₀, N₆₀ and N₉₀ kg ha⁻¹) on crop yield and grain quality of emmer grown in south-central Italy. Fertilizer was split at seeding, tillering and stem elongation. Tested parameters were highly influenced either by crop origin or N application (biomass, hulled and threshed grain yield, spikes m⁻², spikelets per spike, kernel weight, plant height, lodging, kernel ash and proteins). Several parameters augmented as fertilization rate increased (hulled and unhulled grain yield, biomass accumulation, spikes m⁻², kernels m⁻², protein content); 1000-kernel weight showed an opposite trend and in some cases no differences were noticed among fertilized treatments (plant height and spikelets per spike). Molise was the most productive population, closely followed by Garfagnana. The present research rejected some common belief that emmer has to be grown without N dressing, and crop undergoes lodging in marginal mountainous areas. Besides, grain yield of N₉₀ and N₆₀ treated emmer was only 6 and 18% lower compared to the five most important durum wheat varieties cultivated in the same area, suggesting emmer as a possible alternative crop to durum wheat in marginal areas of Mediterranean-type agro-ecosystems.     

Rice dry matter and nitrogen accumulation,soil mineral N around root and N leaching,with increasing application rates of fertilizer

Rice morphology and N leaching, together with mineral N in the soil and soil solution around root, were determined at different growth stages in a 3-year experiment located in the Taihu Lake region, China. The results showed that the N application rates had little impact on the soil mineral N around root, but increased the dry matter and N accumulation aboveground in the high fertility soil (55.3 mg kg⁻¹ of soil mineral N before rice season in 2008). However, no significant difference in grain yield was observed in all N treatments in these 3 years. Path analysis showed that spikelet per panicle made the greatest direct contribution (0.781) and total contribution (0.309) to grain yield compared to other yield components. And a higher panicle per m² and dry matter accumulation resulted in yield decline later in the season due to a decline in the percentage of filled grains.No significant increases in plant N uptake, regardless of N application rates, were observed at the seedling stage, which indicated that lower N application rates could suffice during the rice early growing stages. Nitrate contents, in spite of high N rates input, in the percolation water were all below 1.0 mg L⁻¹ throughout the rice growing season. The increased N rates showed an increment of total N leaching through the percolation water, but not significant. The cumulative total N leaching only accounted for 1.86–4.96% of N fertilizer input, which suggested the N leaching should not be considered as main pollution resources in paddy filed in summer rice season. However, the evaluation of N leaching in different stages indicated that N leaching at seedling stage was larger in dominant (averaged 39.8% of total N leaching) than other stages. For the lower absorbing ability of rice seedling and more N leaching risk, suggestions on N fertilizer reduction should be made at rice early growing stage in this region.     

不同氮效率玉米基因型苗期对光和氮响应的研究

对氮效率表现差异显著的三个玉米自交系幼苗采用不同光强和氮浓度处理,比较根冠比、生物产量、硝酸还原酶和谷氨酰胺合成酶的响应差异。结果表明：不同氮效率自交系对不同氮浓度与光照强度处理的响应存在显著差异;氮低效材料在低光低氮条件下的生物产量表现比氮高效材料好,在高光高氮条件下时生物产量表现比氮高效差;氮高效材料随着氮浓度增加比氮低效材料更能保持根的发达性,表明根系是氮高效的保证。不同氮效率自交系生物产量和硝酸还原酶光氮最佳耦合点值不同,氮低效自交系出现光氮最佳耦合点时所需要的氮浓度（或光强）要比氮高效自交系低。因此,玉米基因型氮效率的发挥不但需要适宜的供氮水平,还需要合适的光照强度。     

不同耐低氮性玉米品种的花后碳氮积累与转运特征

为了探明不同耐低氮性玉米品种生育后期碳、氮物质积累与转运特性及其对氮肥响应的差异,以期为品种高效施氮技术的制定提供理论依据。以耐低氮品种‘正红311’(Zhenghong311,ZH311)和低氮敏感品种‘先玉508’(Xianyu 508, XY508)为材料,设置4个氮肥用量(0、150、300和450 kg hm–2),于2017—2019年研究氮肥水平对不同耐低氮性玉米品种生育后期物质,包括干物质、全氮和非结构性碳水化合物(non-structural carbohydrate, NSC)积累和转运的影响。结果表明,供氮不足时,玉米通过增加花前贮存碳、氮物质对籽粒的转运以保证产量。增施氮肥能够提高玉米花后干物质和碳水化合物生产及其对籽粒质量的贡献率。与低氮敏感品种先玉508相比,在低氮条件下,耐低氮品种正红311在花前、花后均保持较高的植株干物质、NSC和氮素量,花后物质积累量及其对籽粒质量的贡献率更高,从而拥有更高的籽粒产量;品种间花前物质转运率及其对籽粒质量的贡献率差异不大。面对低氮胁迫,正红311既保证了花前贮存物质充分向籽粒运输,同时维持着较高的同化物积累能力来影响其产量形成。     

不同比例氮肥施用对稻田蟹生长及营养价值的影响

采用稻田围隔法,系统地研究了一次性施肥技术中不同有机和无机氮肥比例施用量在稻田养蟹条件下对河蟹（中华绒螯蟹）的生长状况、营养状况及产量的影响。结果表明：与传统施肥方式（FP）和测土推荐施肥方式（OPT）相比,A1配方施肥对河蟹的生长及产量、品质均有较好的效果,河蟹收获时蟹肉可食部分中蛋白质、脂肪、水分含量分别为20.3%、6.3%和72.0%;同时水稻产量也较高,达到10530.5kg/hm2,A1处理的成活率也较高,为 66.7%,能够满足实际生产的需要。而OPT处理只对水稻产量反应较好,对河蟹生长有一定的影响。     

玉米不同氮素水平下产量与zmAspAT基因表达分析

研究不同氮素水平下导入系L18和Y478产量及相关性状的差异以及与zmAspAT基因表达模式的关系。考察L18和Y478在低氮和正常供氮条件下的产量及相关性状,利用实时定量PCR技术分析zmAspAT基因的表达变化。在正常供氮条件下L18的单穗产量比Y478高17.21%,显著增加,行粒数极显著增加,百粒重显著减小;低氮条件下,L18单穗粒重比轮回亲本Y478显著减少,达到20.64%,行粒数显著增加,百粒重极显著减小。在低氮胁迫条件下,zmAspAT基因在L18中下调表达,在Y478则上调表达,表达模式不同。L18是氮低效的导入系,由于zmAspAT基因在L18与Y478表达模式不同,导致了L18较低的氮素利用效率和产量,zmAspAT是重要的玉米氮利用效率基因。