目前，倒伏仍是持续提升小麦产量的关键限制因素，因为在高产栽培的群体中，低光照胁迫会降低茎秆的机械强度。茎秆机械性能由节间木质素决定，其受群体光环境影响。能否通过群体分布改善光照条件抑制茎秆倒伏，迄今了解甚少。为此，本试验以小麦品种“西农979”为试验材料，设置低密度均质分布处理（LD）、高密度均质分布处理（HD）和高密度异质分布处理（HD-h），研究群体分布对小麦茎秆抗倒伏性能的调控效应与作用机制。结果显示，相比于LD处理，HD处理下，冠层中下层透光率、植株中下部叶净光合速率、茎秆木质素积累量、茎秆抗折断力均显著降低，倒伏指数显著上升，而发生倒伏，2020–2021年倒伏率为67.5%，2021–2022年为59.3%。HD-h处理下，冠层中下层透光率等指标则较HD处理明显提高，而倒伏指数降低，且无倒伏现象。在茎秆形成的关键时期，与LD相比，HD条件下茎秆中PAL（苯丙氨酸转氨酶）、4CL（4-香豆酸:辅酶A连接酶）、COMT（咖啡酸3氧甲基转移酶）、CAD（肉桂醇脱氢酶）在木质素合成途径中的活性显著降低，TaPAL, Ta4CL, TaCOMT, 和TaCAD的相对表达量显著下调。然而，与HD相比，HD-h下木质素合成相关酶的活性及其基因表达量显著提高。进一步通过PLS路径分析显示，群体冠层光环境、植株中下部叶光合性能、木质素合成与积累、茎秆抗倒伏性能之间均为显著的正效应。结果表明，在传统高密度种植模式下，小麦倒伏风险增高。在此基础上，通过群体异质性分布调优冠层光环境，提高植株中下部叶光合性能，促进茎秆木质素积累，进而增强小麦抗倒伏性能。这些发现解释了小麦高产栽培条件下茎秆机械强度降低的机理，为小麦抗倒伏技术途径提供思路与理论依据。

Annual loss of crop yields due to agricultural insect pests are approximately 10%.  Effective and safe management of insect pests would reduce the loss of crop production.  Insects live in an environment where they need to deal with biological and non-biological factors that impact their physiological and developmental activities to survive and expand their population.  These environmental factors include, but not limited to, phytochemicals in the host plants they feed on, toxic compounds, such as insecticides sprayed by human, parasitoid, microbes, temperature and drought stress.  In the long-term evolution, insects have developed sophisticated strategies to adapt the harmful factors against them.  For example, to feed on different host plants, insects develop effective and comprehensive olfactory and gustatory receptor systems and detoxification enzyme systems to deal with the secondary toxic phytochemicals.  These olfactory and gustatory receptor and detoxification enzyme systems contain multiple superfamilies of proteins and enzymes, such as cytochrome P450s, glutathione S-transferases (GSTs) and esterases, together to form multiple preventive and protection barriers along with the regulation and function of the endocrine systems, which synthesize and secrete hormones and neuropeptides circulating to the different target tissues and organs to guarantee the normal growth and development.  On the other hand, insects also adjust their feeding behaviors and metabolism pathways, as well as even the nutrient components in the host plants by changing the expression patterns of related genes to promote the nutrient intake and utilization.  Insects and their host plants ultimately establish a cooperative and antagonistic relationship during evolution. 
Insect development is coordinated by various hormones and neuropeptides.  The steroid hormone 20-hydroxyecdysone (20E) activates molting and metamorphosis, while juvenile hormone (JH) maintains larval status (Riddiford 1996; Riddiford et al. 2003).  These two hormones are the most critical hormones that regulate and balance the processes of growth, development and maturation of insects depending on their titers.  They often counteract each other in most of physiological events, but sometimes they also cooperate to regulate some activities, such as reproductive maturation.  20E and JH also involve in insect behavior, for example, feeding behavior, in which high level of 20E suppresses feeding, whereas high level of JH enhances feeding.  Insulin, along with JH, promotes larval growth by feeding more food and 20E opposes insulin and JH functions to initiate metamorphosis (Pan et al. 2018).  These three signal transduction pathways work together to maintain the growth and development on the right track.  Any interference on the intermediate steps in these pathways may result in arrest of the insect growth and development. 
Neuropeptides are a group of small protein molecules, usually synthesized and secreted from nervous systems to cells of the target tissues and organs, where they bind specific membrane receptors, for example, the G-protein-coupled receptors and initiate second-message cascades and then the distinct molecular responses.  It has been found that insect neuropeptides play crucial roles in feeding behavior, growth regulation, locomotor activity and sleep, ethanol sensitivity, learning and memory, aggression, courtship and reproduction, phase switch, osmotic and metabolic stress and hormone release (Nässel and Wegener 2011).
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Perennial waterlogged soil (PWS) is induced by the high level of groundwater, and has a persistent impact on natural ecosystems and agricultural production. Traditionally, distribution information regarding PWS is mainly collected from in situ measurements through groundwater level surveys and physicochemical property analyses. However, in situ measurements of PWS are costly and time-consuming, only rough estimates of PWS areas are available in some regions. In this paper, we developed a method to monitor the perennial waterlogged cropland using time-series moderate resolution imaging spectroradiometer (MODIS) data. The Jianghan Plain, a floodplain located in the middle reaches of the Yangtze River, was selected as the study area. Temporal variations of the enhanced vegetation index (EVI), night land surface temperature (LST), diurnal LST differences (ΔLST), albedo, and the apparent thermal inertia (ATI) were used to analyze the ecological and thermodynamic characteristics of the waterlogged croplands. To obtain pure remote sensing signatures of the waterlogged cropland from mixed pixels, the croplands were classified into different types according to soil and land cover types in this paper, and a linear mixing model was developed by fitting the signatures using the multiple linear regression approach. Afterwards, another linear spectral mixing model was used to get the proportions of waterlogged croplands in each 1 km×1 km pixel. The result showed an acceptable accuracy with a root-mean-square error of 0.093. As a tentative method, the procedure described in this paper works efficiently as a method to monitor the spatial patterns of perennial sub-surface waterlogged croplands at a wide scale.