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1.
【目的】为了探讨施钾对苜蓿上牛角花齿蓟马Odontothrips loti的产卵选择、生长发育、成虫寿命和繁殖力的影响,明确施钾苜蓿叶片营养物含量与牛角花齿蓟马生命参数的关系。【方法】在不同钾量(40, 60, 80和100 mg/kg)处理下(以不施钾作为对照),观察记录牛角花齿蓟马在紫花苜蓿品种甘农3号Medicago sativa cv. Gannong No. 3叶片上的产卵量,幼期各龄期发育历期和存活率以及二代成虫的寿命和繁殖力,同时测定不同施钾量下苜蓿叶片的可溶性糖、游离氨基酸及钾含量。【结果】随着施钾量的增加,牛角花齿蓟马在苜蓿叶片上的产卵量(粒/复叶)先降低后升高,在60 mg/kg钾处理降幅最大,较对照降低了45.58%;卵孵化率和1-2龄若虫的存活率变化不显著,但3-4龄若虫的存活率和幼期总存活率显著下降,分别在100 mg/kg 和80 mg/kg钾处理下降幅最大,较对照分别下降了54.36%和48.48%。不同施钾量下苜蓿叶片上牛角花齿蓟马卵和1-2龄若虫发育历期无显著变化,3-4龄若虫及幼期总发育历期均延长;牛角花齿蓟马二代成虫的繁殖力均显著下降,成虫寿命显著缩短(40 mg/kg钾处理除外)。施钾后,苜蓿叶片可溶性糖含量、钾含量和糖氮比增大,游离氨基酸含量减少。相关关系分析表明,苜蓿叶片钾含量与牛角花齿蓟马幼期总存活率和成虫繁殖力无显著相关性,而苜蓿叶片可溶性糖含量和糖氮比均与3-4龄若虫存活率和繁殖力极显著负相关,与幼期总存活率呈显著负相关。【结论】施钾苜蓿对牛角花齿蓟马成虫产卵产生显著的排趋性;施钾提高了苜蓿叶片的可溶性糖含量及糖氮比,不利于若虫的生长发育,并使成虫寿命缩短、繁殖力下降,对牛角花齿蓟马产生了显著的抗生作用。  相似文献   
2.
石坚  王原  梁佳  杜娟  赵章武 《昆虫学报》2021,64(9):1080-1091
【目的】神经肽F(neuropeptide F, NPF)是无脊椎动物特有的一类神经肽,因其C末端是苯丙氨酸(F)而命名,参与昆虫的取食、生物节律、学习记忆等多种生理功能的调控。本研究旨在明确NPF对亚洲玉米螟Ostrinia furnacalis生长发育的影响,为害虫防治提供重要依据。【方法】采用一种基于工程菌高效合成靶向昆虫基因的dsRNA的方法经济有效地敲降npf,用低浓度(0.01%)和高浓度(0.02%)dsNPF和dsGFP(对照)分别饲喂亚洲玉米螟1龄初、3龄初和5龄初幼虫直至化蛹,检测5龄幼虫平均取食量、体重、体长、存活率和化蛹率,蛹羽化率和成虫产卵量,以及幼虫各龄期、蛹发育历期和成虫寿命。【结果】从亚洲玉米螟1, 3和5龄初幼虫开始饲喂0.01%和0.02% dsNPF时,与饲喂相应浓度dsGFP的对照相比,除个别点外,5龄幼虫的取食量、体重、体长、存活率和化蛹率,蛹羽化率和成虫单雌产卵量均显著降低,幼虫各龄期、蛹发育历期均显著延长,成虫寿命显著缩短。且dsNPF处理幼虫的龄期越早对发育的影响越大。其中0.01% dsNPF处理的1龄幼虫和0.02% dsNPF处理的3龄幼虫有90%的个体在蛹期死亡,而0.02%dsNPF处理的1龄幼虫有90%的个体在幼虫期死亡。【结论】结果提示NPF对亚洲玉米螟的发育和取食具有调控作用,这为探索新型绿色的害虫防治提供了依据。  相似文献   
3.
为探索遮光处理对草珊瑚光合特性及叶片解剖结构的影响,为草珊瑚的科学栽培提供理论依据。该研究以2年生草珊瑚为材料,设置全光照(L_0)及50%(L_(50))、70%(L_(70))和90%(L_(90))遮光处理,测定分析其光合特性和叶片解剖结构以及植株生长的变化。结果表明:(1)随着遮光率的增加,草珊瑚叶面光合有效辐射(PAR)、气孔导度(G_s)和蒸腾速率(T_r)逐渐减小,胞间二氧化碳浓度(C_i)先减少后增加,净光合速率(P_n)先增加后减少,并在L_(50)和L_(70)处理下具有较低的PAR、G_s、T_r和C_i,光合‘午休’现象得到有效缓解,表现出更高的P_n。(2)随着遮光率的增加,草珊瑚光补偿点(LCP)逐渐下降,光饱和点(LSP)、暗呼吸速率(R_d)先升高后下降,表观量子效率(AQE)逐渐上升,叶片最大净光合速率(P_(nmax))先升高后下降,并在L_(50)和L_(70)处理下具有较低的LCP,较高的LSP和AQE,以及更高的最大净光合速率。(3)随着遮光率的增加,草珊瑚叶片、表皮细胞、栅栏组织和海绵组织的厚度明显增加,角质层厚度逐渐变薄;在L_(50)和L_(70)处理下,草珊瑚叶片栅栏组织和海绵组织发达,栅栏组织细胞长度变短,海绵组织厚度显著增加,细胞排列疏松,叶绿体数量显著增加;叶肉细胞和叶绿体结构完整,基粒类囊体和基质类囊体片层结构发达,叶片捕获光能力增强。(4)随着遮光率的增加,草珊瑚株高、地径、总叶面积数及单株生物量先增加后减少,并在L_(70)处理下均达到峰值,分别为58.58 cm、5.09 mm、1 038.53 cm~2和15.50 g。研究认为,草珊瑚具有一定的弱光耐受力和光可塑性,50%~70%遮光处理有利于草珊瑚生长,在实际生产中可根据该光照范围选择合适的间套作林分或进行适当的遮光处理。  相似文献   
4.
间作植物和茬口对连作党参生长和品质产量的影响   总被引:1,自引:0,他引:1  
选择两种茬口(轮作茬、连作茬)和6种植物材料(党参、大蒜、玉米、黄芪、苦参、向日葵),组成党参单作和间作6种种植模式,设置茬口和间作模式两因素田间随机区组试验,通过监测不同生长时期党参的生长指标(蔓长、主根长、主根直径、地下部分鲜干重)、根部产量及品质指标(根部多糖含量、炔苷含量、醇溶性浸出物含量和灰分含量)的变化衡量不同茬口和间作植物对党参连作障碍的缓解效应。结果表明:(1)轮作茬口下党参单作及各间作处理对党参生长、品质和产量的改善效果都较连作茬口下明显,且两茬口下各间作处理的改善效果都较党参单作明显。(2)与向日葵、大蒜和玉米间作处理对两茬口党参的主根长、主根直径、地下部分鲜干重的提升效果比党参单作和其余间作处理(与黄芪、苦参间作)更显著。(3)大蒜和向日葵间作处理能够显著提高两茬口党参根部产量,尤其大蒜表现最优,与其间作的轮作茬和连作茬党参分别较各自对照增产49.92%和22.55%。(4)与大蒜间作能有效提升两茬口党参根部多糖含量、炔苷含量和醇溶性浸出物的含量,党参单作和其余间作处理对两茬口连作党参的品质提升效果不及大蒜间作处理理想。研究发现,从党参长势及根部产量和品质综合分析,两茬口下党参与大蒜间作最有利于党参植株生长,能有效缓解党参连作障碍,并显著提高其药用部位的产量和品质,且轮作茬口下的提高效应更明显。  相似文献   
5.
Strigolactones play crucial roles in regulating plant architecture and development, as endogenous hormones, and orchestrating symbiotic interactions with fungi and parasitic plants, as components of root exudates. rac-GR24 is currently the most widely used strigolactone analog and serves as a reference compound in investigating the action of strigolactones. In this study, we evaluated a suite of debranones and found that 2-nitrodebranone (2NOD) exhibited higher biological activity than rac-GR24 in various aspects of plant growth and development in Arabidopsis, including hypocotyl elongation inhibition, root hair promotion and senescence acceleration. The enhanced activity of 2NOD in promoting AtD14–SMXL7 and AtD14–MAX2 interactions indicates that the molecular structure of 2NOD is a better match for the ligand perception site pocket of D14. Moreover, 2NOD showed lower activity than rac-GR24 in promoting Orobanche cumana seed germination, suggesting its higher ability to control plant architecture than parasitic interactions. In combination with the improved stability of 2NOD, these results demonstrate that 2NOD is a strigolactone analog that can specifically mimic the activity of strigolactones and that 2NOD exhibits strong potential as a tool for studying the strigolactone signaling pathway in plants.  相似文献   
6.
Mass spectrometry is the predominant analytical tool used in the field of plant lipidomics. However, there are many challenges associated with the mass spectrometric detection and identification of lipids because of the highly complex nature of plant lipids. Studies into lipid biosynthetic pathways, gene functions in lipid metabolism, lipid changes during plant growth and development, and the holistic examination of the role of plant lipids in environmental stress responses are often hindered. Here, we leveraged a robust pipeline that we previously established to extract and analyze lipid profiles of different tissues and developmental stages from the model plant Arabidopsis thaliana. We analyzed seven tissues at several different developmental stages and identified more than 200 lipids from each tissue analyzed. The data were used to create a web-accessible in silico lipid map that has been integrated into an electronic Fluorescent Pictograph (eFP) browser. This in silico library of Arabidopsis lipids allows the visualization and exploration of the distribution and changes of lipid levels across selected developmental stages. Furthermore, it provides information on the characteristic fragments of lipids and adducts observed in the mass spectrometer and their retention times, which can be used for lipid identification. The Arabidopsis tissue lipid map can be accessed at http://bar.utoronto.ca/efp_arabidopsis_lipid/cgi-bin/efpWeb.cgi .  相似文献   
7.
Despite the importance of understanding plant growth, the mechanisms underlying how plant and fruit growth declines during drought remain poorly understood. Specifically, it remains unresolved whether carbon or water factors are responsible for limiting growth as drought progresses. We examine questions regarding the relative importance of water and carbon to fruit growth depending on the water deficit level and the fruit growth stage by measuring fruit diameter, leaf photosynthesis, and a proxy of cell turgor in olive (Olea europaea). Flow cytometry was also applied to determine the fruit cell division stage. We found that photosynthesis and turgor were related to fruit growth; specifically, the relative importance of photosynthesis was higher during periods of more intense cell division, while turgor had higher relative importance in periods where cell division comes close to ceasing and fruit growth is dependent mainly on cell expansion. This pattern was found regardless of the water deficit level, although turgor and growth ceased at more similar values of leaf water potential than photosynthesis. Cell division occurred even when fruit growth seemed to stop under water deficit conditions, which likely helped fruits to grow disproportionately when trees were hydrated again, compensating for periods with low turgor. As a result, the final fruit size was not severely penalized. We conclude that carbon and water processes are able to explain fruit growth, with importance placed on the combination of cell division and expansion. However, the major limitation to growth is turgor, which adds evidence to the sink limitation hypothesis.  相似文献   
8.
Plants resist infection through an innate immune response, which is usually associated with slowing of growth. The molecular mechanisms underlying the trade-off between plant growth and defense remain unclear. The present study reveals that growth/defense trade-offs mediated by gibberellin (GA) and salicylic acid (SA) signaling pathways are uncoupled during constitutive overexpression of transgenic AtRAN1 and AtRAN1Q72L (active, GTP-locked form) Arabidopsis plants. It is well known that the small GTP-binding protein Ran (a Ras-related nuclear protein) functions in the nucleus–cytoplasmic transport of proteins. Although there is considerable evidence indicating that nuclear–cytoplasmic partitioning of specific proteins can participate in hormone signaling, the role of Ran-dependent nuclear transport in hormone signaling is not yet fully understood. In this report, we used a combination of genetic and molecular methods to reveal whether AtRAN1 is involved in both GA and SA signaling pathways. Constitutively overexpressed AtRAN1 promoted both elongation growth and the disease resistance response, whereas overexpression of AtRAN1Q72L in the atran2atran3 double mutant background clearly inhibited elongation growth and the defense response. Furthermore, we found that AtRAN1 coordinated plant growth and defense by promoting the stability of the DELLA protein RGA in the nucleus and by modulating NPR1 nuclear localization. Interestingly, genetically modified rice (Oryza sativa) overexpressing AtRAN1 exhibited increased plant height and yield per plant. Altogether, the ability to achieve growth/defense trade-offs through AtRAN1 overexpression provides an approach to maximizing crop yield to meet rising global food demands.  相似文献   
9.
10.
Zinc (Zn) is an essential micronutrient required to enhance crop growth and yield. In the arid – semiarid region, Zn deficiency is expected due to alkaline calcareous soil. Contrarily, Zn toxicity is also becoming an environmental concern due to increasing anthropogenic activities (metal smelting, copper industry, etc.). Therefore, balanced Zn application is necessary to save resources and achieve optimum crop growth and yield. Most scientists suggest biological approaches to overcome the problem of Zn toxicity and deficiency. These biological approaches are mostly environment-friendly and cost-effective. In these biological approaches, the use of arbuscular mycorrhizae fungi (AMF) symbiosis is becoming popular. It can provide tolerance to the host plant against Zn-induced stress. Inoculation of AMF helps in balance uptake of Zn and enhances the growth and yield of crops. On the other hand, maize (Zea mays L.) is an important cereal crop due to its multifarious uses. As maize is an effective host for mycorrhizae symbiosis, that’s why this review was written to elaborate on the beneficial role of arbuscular mycorrhizal fungi (AMF). The review aimed to glance at the recent advances in the use of AMF to enhance nutrient uptake, especially Zn. It was also aimed to discuss the mechanism of AMF to overcome the toxic effect of Zn. We have also discussed the detailed mechanism and physiological improvement in the maize plant. In conclusion, AMF can play an imperative role in improving maize growth, yield, and balance uptake of Zn by alleviating Zn stress and mitigating its toxicity.  相似文献   
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