在高等植物中，茎尖分生组织以规则的间隔（叶序）和时间（叶间期）生成侧生器官。对叶序和叶间期相关突变体分析将加深对植物茎尖结构发育机制的理解。本研究中，扬农啤5号EMS诱变获得一个出叶速率变快、节间数目增多和矮化突变体，命名为mnd8^ynp5。利用图位克隆的方法，mnd8基因定位于5H染色体长臂6.7kb的基因组区间。序列分析表明，HORVU5Hr1G118820在第一个外显子953位发生了C到T单核苷酸突变，导致编码蛋白第318位氨基酸由丙氨酸（Ala）变为缬氨酸（Val）。HORVU5Hr1G118820作为MND8基因的候选基因，编码514个氨基酸，包含两个多药和有毒化合物挤压结构域（MATE），与玉米Bige1高度同源，具有通过控制叶片起始速率来调控植物发育的保守功能。现代大麦品种单倍型分析表明，Hap-1是被全世界大麦育种中应用的主要单倍型。总之，mnd8^ynp5作为HORVU5Hr1G118820基因的新等位基因，调控了大麦叶间期和矮秆多节表型。

B-box（BBX）基因家族编码的蛋白是由包含锌指结构的转录因子组成，其N端有一个或两个高度保守的B-box基序。BBX蛋白在植物生长发育的各个方面起着至关重要的作用，包括幼苗的光形态发生、避荫、开花时间以及生物和非生物胁迫响应。目前,各国的研究者已经从几种植物中鉴定了BBX的家族成员，然而玉米中的BBX家族成员还知之甚少。通过对玉米BBX家族基因的全基因组鉴定、表达和互作的综合分析，可为了解其功能提供有用信息。本研究共鉴定出36个玉米BBX家族成员，进化分析显示其分布于三个主要分支。在每个主分支中ZmBBXs都具有相似的结构域、基序和基因组结构。基因重复分析表明，玉米BBX蛋白家族的扩张主要是通过片段重复来完成的。利用实时荧光定量PCR技术，本研究分析了ZmBBXs在不同器官组织和不同非生物胁迫条件下的表达。利用生物信息学工具，本研究建立了ZmBBXs蛋白的相互作用网络，并通过双分子荧光互补（BiFC）试验进行了验证。本研究的发现有助于理解ZmBBX家族的复杂性，并为揭示ZmBBX蛋白的生物学功能提供新的线索。

打顶是棉花栽培广泛应用的农艺措施由于其无限生长的习性。在不同的打顶方法中，人工打顶似然费时费力，但在黄河流域应用较为普遍。本研究旨在研究不同打顶处理对棉花发育、产量和品质的影响。本研究为两年（2015-2016）大田实验，设置三种打顶方式：人工打顶（MT），化学打顶（CT）（缩节铵），不打顶（NT）处理。我们发现CT处理的株高、果枝数及上部果枝长度要显著低于NT处理。CT处理的叶绿素含量与NT处理相比无显著差异，在生育后期要高于MT处理。CT处理通过降低赤霉素和脱落酸含量来促进棉株发育，并且抑制了主茎的顶端发育。和MT处理相比，CT处理显著增加了营养器官的生物量。最重要的是，CT和MT处理间的产量和品质并无显著差异。上述结果表明，化学打顶是一种简便、有效的打顶方法，可在我国黄河流域代替人工打顶。

氮素是水稻取得高产的重要因素之一。除高产外，优质已成为当前水稻生产的又一迫切要求。灌浆期是水稻产量和品质形成的关键时期。而氮素对籼稻籽粒灌浆特性的影响及其与稻米品质的关系仍不清楚。通过大田栽培试验，研究了施氮条件下籽粒灌浆的关键特性与稻米研磨品质、外观品质和蒸煮食味品质的变化。结果表明，施氮延长了强、弱势粒灌浆的持续时间。弱势粒的平均灌浆速率（G_mean）和最大灌浆速率（G_max）与垩白粒率、垩白度和直链淀粉含量呈正相关关系。弱势粒达到最大灌浆速率的时间（T_max G）与糙米率、精米率和整精米率呈正相关关系。垩白粒率、垩白度与最高黏度、崩解值呈负相关关系。2016年和2017年两优培九和Y两优2号两个品种均在施氮后出现直链淀粉含量下降，粗蛋白含量增加。相关性分析说明，直链淀粉含量较低的Y两优2号蒸煮食味品质较好，可能是其弱势粒的最大灌浆速率（G_max）和平均灌浆速率（G_mean）高于两优培九所引起的。施氮后弱势籽粒灌浆时间的延长和达到最大灌浆速率时粒重的增加可以提高中籼稻的碾磨品质、外观品质和蒸煮食味品质。

    In this study, the proximate composition, mineral content and amino acid composition of starch processing residues from 10 cultivars of sweet potato and 10 cultivars of potato were determined, and the nutritional and health-related values of these residues were investigated.  The residual flours contained 20.63–31.48 g and 17.14–28.57 g rich dietary fiber per 100 g dry weight for sweet potato and potato, respectively, as well as mineral elements, including potassium, ferrum, zinc and copper.  The highest limiting amino acid score (AAS) of the almost balanced amino acid composition were observed to be 71.07 and 57.96 for sweet potato and potato residues, respectively.  A grey relational analysis showed that the nutritional values of Jishu 4 at 0.7519 and LT-5 at 0.7281 were the highest among the sweet potato and potato residues, respectively.  The evaluation of the sweet potato/potato residues, the by-products of the starch industry, based on recommended daily intake (RDI) standards, indicated that the residues have potential nutritional and health-related food values. 

We carried out a pool culture experiment to determine the optimal water treatment depth in loam and clay soils during the late growth stage of super rice.  Three controlled water depth treatments of 0–5, 0–10 and 0–15 cm below the soil surface were established using alternate wetting and drying irrigation, and the soil water potential (0 to –25 kPa) was measured at 5, 10 and 15 cm.  A 2-cm water layer was used as the control.  We measured soil enzyme activities, root antioxidant enzyme activities, chlorophyll fluorescence parameters, and rice yield.  The results showed that the 0–5-cm water depth treatment significantly increased root antioxidant enzyme activities in loam soil compared with the control, whereas soil enzyme activities, chlorophyll fluorescence parameters and yield did not differ from those of the control.  The 0–10- and 0–15-cm water depth treatments also increased root antioxidant enzyme activities, whereas soil enzyme activities, chlorophyll fluorescence parameters and yield decreased.  In clay soil, the soil enzyme activities, root antioxidant enzyme activities, chlorophyll fluorescence parameters, and yield did not change with the 0–5-cm water treatment, whereas the 0–10- and 0–15-cm water treatments improved these parameters.  Therefore, the appropriate depths for soil water during the late growth period of rice with a 0 to –25 kPa water potential were 5 cm in loam and 15 cm in clay soil.

H9 subtype avian influenza virus (AIV) and infectious bronchitis virus (IBV) are major pathogens circulating in poultry and have resulted in great economic losses due to respiratory disease and reduced egg production. As similar symptoms are elicited by the two pathogens, it is difficult for their differential diagnosis. So far, no reverse transcription-polymerase chain reaction (RT-PCR) assay has been found to differentiate between H9 AIV and IBV in one reaction. Therefore, developing a sensitive and specific method is of importance to simultaneously detect and differentiate H9 AIV and IBV. In this study, a duplex RT-PCR (dRT-PCR) was established. Two primer sets target the hemagglutinin (HA) gene of H9 AIV and the nucleocapsid (N) gene of IBV, respectively. Specific PCR products were obtained from all tested H9 AIVs and IBVs belonging to the major clades circulating in China, but not from AIVs of other subtypes or other in·fectious avian viruses. The sensitivity of the dRT-PCR assay corresponding to H9 AIV, IBV and mixture of H9 AIV and IBV were at a concentration of 1×10¹, 1.5×10¹ and 1.5×10¹ 50% egg infective doses (EID50) mL^–1, respectively. The concordance rates between the dRT-PCR and virus isolation were 99.1 and 98.2%, respectively, for detection of samples from H9N2 AIV or IBV infected chickens, while the concordance rate was 99.1% for detection of samples from H9N2 AIV and IBV co-infected chickens. Thus, the dRT-PCR assay reported herein is specific and sensitive, and suitable for the differential diagnosis of clinical infections and surveillance of H9 AIVs and IBVs.

    In the dominant winter wheat (WW)-summer maize (SM) double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to realize high crop productivity. Using the vast water resources of the saline upper aquifer for irrigation during WW jointing stage, may help to bridge the peak of dry season and relieve the tight water situation in the region. A field experiment was conducted during 2009–2012 to investigate the effects of saline irrigation during WW jointing stage on soil salt accumulation and productivity of WW and SM. The experiment treatments comprised no irrigation (T1), fresh water irrigation (T2), slightly saline water irrigation (T3: 2.8 dS m^–1), and strongly saline water irrigation (T4: 8.2 dS m^–1) at WW jointing stage. With regard to WW yields and aggregated annual WW-SM yields, clear benefits of saline water irrigation (T3 & T4) compared to no irrigation (T1), as well as insignificant yield losses compared to fresh water irrigation (T2) occurred in all three experiment years. However, the increased soil salinity in early SM season in consequence of saline irrigation exerted a negative effect on SM photosynthesis and final yield in two of three experiment years. To avoid the negative aftereffects of saline irrigation, sufficient fresh water irrigation during SM sowing phase (i.e., increase from 60 to 90 mm) is recommended to guarantee good growth conditions during the sensitive early growing period of SM. The risk of long-term accumulation of salts as a result of saline irrigation during the peak of dry season is considered low, due to deep leaching of salts during regularly occurring wet years, as demonstrated in the 2012 experiment year. Thus, applying saline water irrigation at jointing stage of WW and fresh water at sowing of SM is most promising to realize high yield and fresh irrigation water saving.

    It is a novel idea to make steamed bread by adding potato flour into wheat flour considering the production and nutritional factors of potato. In this study, the influence of potato flour (0–35%) on dough rheology and quality of steamed bread were investigated. Potato flour addition significantly influenced the dough rheological properties and steamed bread quality, such as increased water absorption, the maximum gaseous release height, total volume of CO₂ and hardness, while decreased dough stability and specific volume of steamed bread. Moreover, correlation analysis suggested that dough height at the maximum development time, dough stability, water absorption and the phase tangent can be used for predicting the technological quality of steamed bread. Potato-wheat steamed bread had higher dietary fibre, ash content and antioxidant activity than those of wheat steamed bread. The estimated glycemic index decreased from 73.63 (0%) to 60.01 (35%). Considering the sensory evaluation, the steamed bread with 20% potato flour is acceptable. In conclusion, adding appropriate quantity of potato flour to wheat flour for steamed bread production will not only maintain the technological quality, but also can improve the nutritional value of the steamed bread.

    Swine influenza A virus (swine IAV) circulates worldwide in pigs and poses a serious public health threat, as evidenced by the 2009 H1N1 influenza pandemic. Among multiple subtypes/lineages of swine influenza A viruses, European avian-like (EA) H1N1 swine IAV has been dominant since 2005 in China and caused infections in humans in 2010. Highly sensitive and specific methods of detection are required to differentiate EA H1N1 swine IAVs from viruses belonging to other lineages and subtypes. In this study, a nested reverse transcription (RT)-PCR assay was developed to detect EA H1 swine IAVs. Two primer sets (outer and inner) were designed specifically to target the viral hemagglutinin genes. Specific PCR products were obtained from all tested EA H1N1 swine IAV isolates, but not from other lineages of H1 swine IAVs, other subtypes of swine IAVs, or other infectious swine viruses. The sensitivity of the nested RT-PCR was improved to 1 plaque forming unit (PFU) mL^–1 which was over 104 PFU mL^–1 for a previously established multiplex RT-PCR method. The nested RT-PCR results obtained from screening 365 clinical samples were consistent with those obtained using conventional virus isolation methods combined with sequencing. Thus, the nested RT-PCR assay reported herein is more sensitive and suitable for the diagnosis of clinical infections and surveillance of EA H1 swine IAVs in pigs and humans.

The rapidly growing demand for food, feed and fuel requires further improvements of land and water management, crop productivity and resource-use efficiencies. Combined field experimentation and crop growth modelling during the past five decades made a great leap forward in the understanding of factors that determine actual and potential yields of monocrops. The research field of production ecology developed concepts to integrate biological and biophysical processes with the aim to explore crop growth potential in contrasting environments. To understand the potential of more complex systems (multi-cropping and intercropping) we need an agro-ecosystem approach that integrates knowledge derived from various disciplines: agronomy, crop physiology, crop ecology, and environmental sciences (soil, water and climate). Adaptation of cropping systems to climate change and a better tolerance to biotic and abiotic stresses by genetic improvement and by managing diverse cropping systems in a sustainable way will be of key importance in food security. To accelerate sustainable intensification of agricultural production, it is required to develop intercropping systems that are highly productive and stable under conditions with abiotic constraints (water, nutrients and weather). Strategies to achieve sustainable intensification include developing tools to evaluate crop growth potential under more extreme climatic conditions and introducing new crops and cropping systems that are more productive and robust under conditions with abiotic stress. This paper presents some examples of sustainable intensification management of intercropping systems that proved to be tolerant to extreme climate conditions.

Rice panicles are composed of many branches with two types of extreme grains, the superior and the inferior. Traditionally, it has been well accepted that earlier flowers result in superior grains and late flowers generate inferior grains. However, these correlations have never been strictly examined in practice. In order to determine the accurate relationship between superior and inferior grains and the flowering order, we localized all the seeds in a panicle in four distinct rice species and systematically documented the rice flowering order, flower locations and the final grain weight for their relationships. Our results demonstrated that the grain weight is more heavily determined by the position of the seeds than by the flowering order. Despite earlier flowering has a positive correlation with the grain weight in general, grains from flowers blooming on the second day after anthesis generally gained the highest weight. This suggests earlier flowers may not result in superior grains. Therefore, we concluded that superior and inferior grains, commonly determined by grain weight, are not fully correlated with the flowering order in rice. Following the order of the grain weight, the superior grains are generally localized at the middle parts of the primary branches, whereas inferior grains were mainly on the last two secondary branches of the lower half part of the panicle. In addition, the weight of inferior grains were affected by spikelet thinning and spraying with exogenous plant growth regulators, indicating that physiological incompetence might be the major reason for the occurrence of the inferior grains.

In order to monitor plant chlorophyll content in real-time, a new vehicle-mounted detection system was developed to measure crop canopy spectral characteristics. It was designed to work as a wireless sensor network with one control unit and one measuring unit. The control unit included a personal digital assistant (PDA) device with a ZigBee wireless network coordinator. As the coordinator of the whole wireless network, the control unit was used to receive, display and store all the data sent from sensor nodes. The measuring unit consisted of several optical sensor nodes. All the sensor nodes were mounted on an on-board mechanical structure so that the measuring unit could collect the canopy spectral data while moving. Each sensor node contained four optical channels to measure the light radiation at the wavebands of 550, 650, 766, and 850 nm. The calibration tests verified a good performance in terms of the wireless transmission ability and the sensor measurement precision. Both stationary and moving field experiments were also conducted in a winter wheat experimental field. There was a high correlation between chlorophyll content and vegetation index, and several estimation models of the chlorophyll content were established. The highest R2 of the estimation models was 0.718. The results showed that the vehicle-mounted crop detection system has potential for field application.