Kernel number determination differs among maize hybrids in response to nitrogen

In maize, the effects of nitrogen (N) deficiencies on the determination of kernel number per plant (KNP) have been described only by changes in plant growth rate during the critical period for kernel set (PGRcp). We hypothesize that N availability affects KNP also through variations in biomass allocation to the ear, which determines a stable N concentration in this organ. Six maize hybrids of different breeding origin were evaluated in field experiments at two N levels (0 and 400 kg N ha⁻¹ applied). Traits included were KNP and per apical ear (KN_E1), and the allometric estimation of PGRcp, ear growth rate during the critical period (EGRcp), and N content and N concentration in different plant organs. We demonstrated that (i) N availability promoted differences among genotypes (G) in the response of EGRcp and KNP to PGRcp, (ii) variations in KN_E1 were explained by EGRcp (r² = 0.64) and by ear N content at silking + 12 d (r² = 0.64), and (iii) ear N concentration was a highly conservative trait (range between 10.47 and 15.98 mg N g biomass⁻¹) as compared to N concentration in vegetative tissues (range between 4.94 and 18.04 mg N g biomass⁻¹). Three response patterns were detected among hybrids, one for which the relationship between EGRcp and PGRcp did not vary between N levels and experiments, a second one for which N availability affected this relationship, and a third one for which the response was affected by the year (Y) effect. These results, together with the high correlation between EGRcp and ear N content (r² = 0.88), evidenced the importance of both photo-assimilate and N availability on EGRcp and KNP determination. Values of 1.5–2.3 g ear⁻¹ d⁻¹ during the critical period and 0.49–0.70 g of N ear⁻¹ at silking + 12 d were determined as thresholds for maximizing KN_E1, and both could be easily estimated by means of allometric models.     

欧李仁植物蛋白饮料的研制及其营养特性分析

以欧李仁为原料制备植物蛋白饮料,并评价其营养特性。在单因素试验的基础上,采用正交试验确定欧李仁植物蛋白饮料的最佳配方为：料液比1∶20（g/mL）,蔗糖添加量4%,蔗糖脂肪酸酯添加量0.06%,黄原胶添加量0.10%。采用该配方制作的饮料中含14种氨基酸,总量为0.955 mg/mL,其中6种为人体必需氨基酸（苏氨酸、缬氨酸、异亮氨酸、亮氨酸、苯丙氨酸、赖氨酸）,总量为0.336 mg/mL,占氨基酸总量的35.18%。同时,含有亚油酸、油酸、棕榈酸、二十碳五烯酸（EPA）、硬脂酸、十三烷酸、二十二碳二烯酸7种脂肪酸,其中油酸和亚油酸含量较高,分别为59.80 mg/100 g和66.40 mg/100 g。采用上述配方研制的饮料产品呈乳白色,香味浓郁,稳定性好,具有较高的营养价值和保健功能。     

湖北省湿地植物多样性调查与生态修复策略研究

以湿地植物多样性调查为切入点,在研究区域科学合理布设调查样点,基于ArcGIS核密度分析法探究湿地分布规律,基于多样性指数计算法对临港湿地浮游植物做出评价,基于物种多样性和谱系多样性,以PSV和PSE指数计算湖北省湿地植物多样性特征。对湖北省湿地面积分布特征、湿地植物群落特征、湿地植物多样性以及湿地植物生活型及生态型进行分析,结果表明,湖北省湿地具有较明显的空间集聚分布特征以及植物多样性差距。提出科学规划植物分布,全方位进行清淤截污,合理控制水位变化等生态修复策略。     

玉米种子内部机械裂纹检测与机理研究

为深入研究因脱粒造成的玉米种子内部机械裂纹机理及其对发芽与出苗的影响,构建玉米种子内部机械损伤计算机识别系统,改进玉米种子脱粒原理和脱粒部件参数,研究了盛单216等3个品种玉米种子的籽粒外观特征,并借助体视显微技术分析了内部机械裂纹损伤特征、分布状况与形成规律等,探讨了玉米种子内部机械裂纹的成因。研究结果表明：玉米种子籽粒外形和内部机械裂纹状况差异显著;3种玉米种子普遍存在内部机械裂纹,长裂纹损伤率平均为39.8%;果穗喂入时籽粒冠部受到脱粒部件的冲击是裂纹形成的主要原因,在玉米籽粒冠部形成冲击区并产生裂纹,裂纹向胚部扩展;内部裂纹信息应从籽粒冠部和背面提取。     

Growth performance and feeding utilization of alternative feed for adult horseshoe crabs Carcinoscorpius rotundicauda kept in captivity

The aquafeed development has been initiated for horseshoe crabs in captivity. However, much of the attentions were to the juveniles for their widely used in research. Until recently, the research had incorporated the adult horseshoe crabs. This study aims to 1) determine the best alternative feeds for adult males of Carcinoscorpius rotundicauda, 2) measure the acceptance rate of feed, and 3) feeding utilization. Three semi‐moist pellets were either developed or purchased: fish (Decapterus russeli) and cockle (Anadara granosa) pellets (A), fish pellets (B) and keropok pellets (C). Natural feeds act as control: cockle, Anadara granosa (D) and fish, D. russeli (E). The horseshoe crabs were fed daily for 5 weeks and were analysed on their feed percentage consumption, body weight changes, feeding rate (FR), absorption efficiency (AE), feeding conversion ratio (FCR) and specific growth rate (SGR). Feed A was consumed the most (56.21%) with the highest FR (1.88%). It was influenced by the pellet's hardness, where horseshoe crabs favoured softer pellets. Body weight changes, FCR and SGR also showed a similar trend of favouring alternative feed over natural feed. Alternative feeds served a better feed than the natural feed and can be an option for future natural feed replacement for adult horseshoe crabs in captivity. Alternative feed served a better diet than the natural feed and Feed B served the best feed among the three alternative feeds with good C. rotundicauda growth performance and the feed itself is cost‐wise.     

Study of corn kernel breakage susceptibility as a function of its moisture content by using a laboratory grinding method

The rate of corn kernel breakage in the grain combine harvesters is a crucial factor affecting the quality of the grain shelled in the field. The objective of the present study was to determine the susceptibility of corn kernels to breakage based on the kernel moisture content in order to determine the moisture content that corresponds to the lowest rate of breakage.In addition, we evaluated the resistance to breakage of various corn cultivars. A total of 17 different corn cultivars were planted...     

普通小麦Soru#1×Naxos群体代谢物的QTL定位

以Soru#1×Naxos构建的RIL群体为材料,对成熟籽粒进行代谢组学测定。结果显示:所检测到的478种已知代谢物含量具有较高遗传力和不同程度的含量变异,这些代谢物中处于同一代谢通路的结构相似的物质具有相似的含量分布规律。对这些代谢物含量数据进行QTL定位,共获得236种代谢物对应的385个mQTL位点,其中5个位点为被5种以上代谢物共定位的热点区域,分别位于5A(2个热点区域)、5B(1个)、6A(1个)和6B(1个)染色体。这些热点中有3个由Naxos提供,2个由Soru#1提供。     

野生大麦和栽培大麦籽粒性状及蛋白质含量的多样性分析

为了加强种质资源开发与利用,改良大麦籽粒性状,选用来自国内外214份大麦材料,按照其地理来源、棱型、皮裸性进行分类;并对其9个籽粒表型性状和籽粒蛋白质含量(grain protein content, GPC)进行多样性比较分析。结果显示:按遗传进化关系划分,野生大麦的GPC(10.89%)、粒长(11.36 mm)与籽粒直径(5.57 mm)均显著高于栽培大麦的GPC(9.06%)、粒长(8.97 mm)与籽粒直径(5.10 mm);而野生大麦的粒宽(2.99 mm)和籽粒圆度(0.26)显著低于栽培大麦粒宽(3.12 mm)和籽粒圆度(0.34);栽培大麦和野生大麦之间千粒重差异不显著。按地理来源划分,中亚野生大麦和西南亚野生大麦各籽粒性状均无显著差异,所有地区中西藏野生大麦表现出最高千粒重(36.25 g)和最低GPC(6.85%)。6个地区栽培大麦的GPC由于长期的人工选育已经趋于大致相同水平。按其棱型划分,野生二棱大麦的GPC(11.26%)显著高于野生六棱大麦(7.30%),而其千粒重(30.77 g)却显著低于六棱野生大麦(34.66 g);相反,栽培二棱大麦的GPC(8...     

澳洲坚果果仁氨基酸含量的差异性分析

为了进一步了解澳洲坚果果仁的营养品质,为澳洲坚果良种选育提供参考依据,对5个品种澳洲坚果果仁氨基酸的种类、含量进行了测定与分析。结果表明:澳洲坚果果仁富含17种氨基酸,其中含有人体必需氨基酸7种,必需氨基酸占氨基酸总量的27.86%,并且比例稳定,变异系数仅为2.2%;澳洲坚果果仁氨基酸的种类以脂肪族氨基酸为主,芳香族和杂环族氨基酸也占有较大的比例。