烯效唑和硼肥对杂交小麦制种产量的影响

用种量大,制种产量低是限制杂交小麦大面积推广的关键问题之一。以烯效唑、Openall、硼肥3种化学物质处理小麦不育系,旨在选择提高杂交小麦制种产量的化学物质组合。结果发现,每公顷喷施烯效唑5%粉剂112.5 g和硼砂2 505 g,制种产量可提高22.2%,异交结实率提高6.6个百分点,开颖角度明显增加。     

Excessive nitrogen application decreases grain yield and increases nitrogen loss in a wheat–soil system

Abstract

Excessive use of nitrogen (N) fertilizers in wheat fields has led to elevated NO₃-N concentrations in groundwater and reduced N use efficiency. Three-year field and ¹⁵N tracing experiments were conducted to investigate the effects of N application rates on N uptake from basal and topdressing ¹⁵N, N use efficiency, and grain yield in winter wheat plants; and determine the dynamics of N derived from both basal and topdressing ¹⁵N in soil in high-yielding fields. The results showed that 69.5–84.5% of N accumulated in wheat plants derived from soil, while 6.0–12.5%and 9.2–18.1% derived from basal ¹⁵N and top ¹⁵N fertilizer, respectively. The basal N fertilizer recovery averaged 33.9% in plants, residual averaged 59.2% in 0–200 cm depth soil; the topdressing N fertilizer recovery averaged 50.5% in plants, residual averaged 48.2% in 0–200 cm soil. More top ¹⁵N was accumulated in plants and more remained in 0–100 cm soil rather than in 100–200 cm soil at maturity, compared with the basal ¹⁵N. However, during the period from pre-sowing to pre-wintering, the soil nitrate moved down to deeper layers, and most accumulated in the layers below 140 cm. With an increase of N fertilizer rate, the proportion of the N derived from soil in plants decreased, but that derived from basal and topdressing fertilizer increased; the proportion of basal and top ¹⁵N recovery in plants decreased, and that of residual in soil increased. A moderate application rate of 96–168 kg N ha^?1 led to increases in nitrate content in 0–60 cm soil layer, N uptake amount, grain yield and apparent recovery fraction of applied fertilizer N in wheat. Applying above 240 kg N ha^?1 promoted the downward movement of basal and top ¹⁵N and soil nitrate, but had no significant effect on N uptake amount; the excessive N application also obviously decreased the grain yield, N uptake efficiency, apparent recovery fraction of applied fertilizer N, physiological efficiency and internal N use efficiency. It is suggested that the appropriate application rate of nitrogen on a high-yielding wheat field was 96–168 kg N ha^?1.     

春伐桑树不同伐条部位与桑叶产量的关系

通过春伐桑树不同伐条部位对产叶量影响的初步试验表明,在其它桑园管理措施一致的前提下,采取距离一年生枝条基部4～6 cm处（留芽2～3芽）伐条的剪伐方式,可显著提高芽条生长量和春叶产量,极显著提高秋叶产量,同时影响桑树生长发育.     

周宁县春种马铃薯新品种比较试验

马铃薯新品种中薯3号、紫花851、福克76和福克212在福建周宁试种。从品种的特征特性、晚疫病抗性及鲜薯产量综合分析,4个品种的鲜薯产量均比对照品种克新3号高,对晚疫病抗性均表现高抗或抗病,除了福克76裂薯较多外,其余3个品种的综合性状均表现较好。计划进一步加大对中薯3号、紫花851和福克212的引进力度,加快周宁县马铃薯老品种的更新换代步伐。同时继续引进新品种进行试种,增加农户对新品种的可选择性。     

农户田块尺度冬小麦不同产量水平土壤细菌群落差异

为了明确土壤细菌群落对小麦产量的影响，以河南省济源市冬小麦种植户田块为研究对象，通过采集扬花期麦田土壤样品，利用Illumina高通量测序技术测定细菌16S rRNA V3+V4区序列，分析冬小麦不同产量水平土壤的细菌群落差异。结果表明，高产组土壤铵态氮含量显著高于低产组(P<0.05),土壤有机质含量、速效钾含量、有效磷含量、硝态氮含量、pH值在组间均无显著差异，土壤酸性磷酸酶、碱性磷酸酶、脲酶和过氧化氢酶活性在组间也均无显著差异。酸杆菌门(Acidobacteria)和变形菌门(Proteobacteria)是土壤细菌群落的主导菌门。门水平上，小麦产量与芽单胞菌门(Gemmatimonadetes)、装甲菌门(Armatimonadetes)、纤维杆菌门(Fibrobacteres)、Latescibacteria、Dadabacteria相对丰度显著相关。属水平上，Bryobacter、黄杆菌属(Flavisolibacter)、芽单胞菌属(Gemmatimonas)、丰佑菌属(Opitutus)、黏液杆菌属(Mucilaginibacter)、Dongia、Chryseo...     

Contributing traits for nitrogen use efficiency in selected wheat genotypes and corollary between screening methodologies

ABSTRACT

Nitrogen uptake being part of nitrogen use efficiency (NUE) is largely decided by root traits. Root traits variability has hardly been explored by breeders mainly because of difficulties in scoring. The hydroponic system requiring lesser space for precise phenotyping of large numbers of genotypes independently of the growing season can be a suitable alternative. However, the effectiveness of hydroponic screening methods needs to be verified under the soil condition of the field or pot. In the present study, root traits and NUE were investigated in 19 genotypes under two conditions (hydroponic and pipe filled with soil). Both environments revealed large variability for root traits and NUE under high and low N conditions establishing the absence of any direct selection for these traits in the past. Under both sets of experimentation, NUpE was largely responsible for improved nitrogen efficiency mainly because of higher root biomass. The significant association between the two screening methods i.e. hydroponic and pot filled with soil under both low and high N condition support large scale screening for root traits under hydroponic condition.     

小麦醇溶蛋白组分的遗传研究

选取杂交组合(晋麦13×晋农190)通过A-PAGE技术并结合统计分析,分析了单个醇溶蛋白谱带在杂交后代中的遗传规律。醇溶蛋白谱带遗传在F2代表现为:6条谱带的分离(出现/缺失的比率)符合一对基因的分离规律,它们分别是13.9、23.2、26.0、40.2、50.0和71.5;5条谱带的分离符合两对有互补作用的基因的分离规律,它们分别是12.9、15.7、17.8、32.2、76.8,另外有2条谱带的分离符合两对独立基因的分离规律,它们分别是16.5、19.1。     

豫北地区强筋小麦育种技术体系的哲学思考

以马克思辩证唯物主义理论和科学发展观为基础,针对豫北地区强筋小麦育种面临的问题,探讨了强筋小麦育种技术体系。新麦系列优质强筋高产高效小麦品种的育种实践表明,新品种与栽培技术、产业加工的有机结合能够适应当前豫北地区的农业发展需要,值得借鉴和学习。     

Effect of Dietary Supplementation with Hydrolyzed Wheat Gluten on Growth Performance,Cell Immunity and Serum Biochemical Indices of Weaned Piglets （Sus scrofa）

To investigate the effects of dietary supplementation with hydrolyzed wheat gluten (HWG) on growth performance, cell immunity and serum biochemical indices of weaned piglets, 160 crossed (Large White×Landrace) and weaned piglets were randomly divided into 4 treatments with 4 replicates of 10 piglets each. The piglets in each treatment were fed an experimental diet containing either 0 g kg-1 HWG (control group), 30 g kg-1 HWG (3% HWG group), 50 g kg-1 HWG (5% HWG group), or 2.5 g kg-1 glycyl-L-glutamine (0.25% Gly-Gln group). The results showed that the diarrhea rates in 3% HWG and 5% HWG groups were significantly lower than in control group from d 1 to 14 (P＜0.05), while the average daily gain (ADG) in each of two groups was increased (P＞0.05). When compared with control group, dietary supplementation with 3% HWG increased the ratio of CD4+:CD8+ and the ratio of serum albumin and globulin concentrations (A:G) on d 14 and 28, as well as the proliferation of T- and B-lymphocytes (P＞0.05) on d 28. In addition, on d 14 and 28, the A:G ratio in 5% HWG group was significantly higher than in control group (P＜0.05), while the ratio of CD4+:CD8+ increased slightly (P＞0.05). Interestingly, 0.25% Gly-Gln group had higher proportion of CD3+ (P＞0.05) and CD4+ (P＜0.05) on d 14 than control group, but growth performances of 0.25% Gly-Gln group were negatively affected at all experiment stages. These results suggested that HWG might improve the growth performance of piglets by strengthening cell immunity and decreasing the occurrence of diarrhea during the prophase after weaning.