Deletion of a 1,049 bp sequence from the 5′UTR upstream of the SiHEC3 gene induces a seed non-shattering mutation in sesame

Sesame is a labor intensive crop with limited mechanized harvesting mainly due to the seed shattering(SS)trait.In this study,we performed a genetic analysis of the seed-shattering resistance(SR)trait with a SR sesame mutant 12M07.Unlike the SS type,the parenchyma cells in the abscission zone of the 12M07 mutant are arranged loosely but adhere to the seed coat.Inheritance analysis of six generations derived from 12M07(SR)×Xiangcheng Dazibai(SS)showed that the SR trait is recessive and controlled by a single gene pair.Association mapping of the F2population with 888,619 variants(single-nucleotide polymorphisms(SNPs)and insertion-deletion(InDels))and 31,884 structural variations(SVs)determined that only SV12002 in the 5′upstream region of gene Sindi0765000(named SiHEC3)in Chr.3 was significantly associated with the SR trait.SiHEC3 encodes the bHLH transcription factor.A 1,049 bp deletion occurred in the 5′UTR of Sihec3 in 12M07.SiHEC3 is mainly expressed in developing placental tissues,with the expression peaking in capsules at 45 days after pollination.A dual-luciferase reporter assay in tobacco confirmed that the promoter activity of Sihec3 was reduced because of the deletion of the 1,049 bp promoter sequence.Protein–protein interaction network analysis showed that HEC3 is co-expressed with nine key proteins,such as SHATTERPROOF1(SHP1)and SEEDSTICK(STK)which participate in the secondary wall biosynthesis of the abscission layer in plants.The findings of this study show the important function of Sihec3corresponding with the SR trait and supply the genetic information for breeding new varieties that are amenable to mechanized harvesting in sesame and other crops.

Phenotypical and gene co-expression network analyses of seed shattering in divergent sorghum(Sorghum spp.)

Sorghum[Sorghum bicolor(L.)Moench],a multipurpose C4 crop,is also a model species of the Poaceae family for plant research.During the process of domestication,the modification of seed dispersal mode is considered a key event,as the loss of seed shattering caused a significant increase in yield.In order to understand the seed shattering process in sorghum,we further studied eight previously identified divergent sorghum germplasm with different shattering degrees.We described their phenotypes in great detail,analyzed the histology of abscission zone,and conducted a gene co-expression analysis.We observed that the abscission layer of the most strong-shattering varieties began to differentiate before the 5-10 cm panicles development stage and was completely formed at flag leaf unfolding.The protective cells on the pedicels were also fully lignified by flowering.Through the weighted gene correlation network analysis(WGCNA),we mined for candidate genes involved in the abscission process at the heading stage.We found that these genes were mainly associated with such biological processes as hormone signal transmission(SORBI_3003G361300,SORBI_3006G216500,SORBI_3009G027800,SORBI_3007G077200),cell wall modification and degradation(SORBI_3002G205500,SORBI_3004G013800,SORBI_3010G022400,SORBI_3003G251800,SORBI_3003G254700,SORBI_3003G410800,SORBI_3009G162700,SORBI_3001G406700,SORBI_3004G042700,SORBI_3004G244600,SORBI_3001G099100),and lignin synthesis(SORBI_3004G220700,SORBI_3004G062500,SORBI_3010G214900,SORBI_3009G181800).Our study has provided candidate genes required for shedding for further study.We believe that function characterization of these genes may provide insight into our understanding of seed shattering process.

35kV输电线路玻璃绝缘子串中残锤的危害分析

针对35 kV输电线路玻璃绝缘子零值自爆后的残锤,分析残锤的外绝缘、内绝缘特性,并结合两个实例分析在大风大雨作用下35 kV输电线路玻璃绝缘子串中残锤的危害,还针对残锤的危害提出了反措。结果表明:雨水可通过残锤的外绝缘渗浸内绝缘;运行中若未能及时发现和更换残锤,大风大雨将有可能引发存在残锤的35 kV输电线路玻璃绝缘子串发生单相接地闪络故障。其中,在残锤的内绝缘没有被雨水渗浸前,其内绝缘水平高于外绝缘水平,闪络电弧从残锤的外绝缘直接拉弧导通,将有可能导致单相接地闪络故障延时跳闸的35 kV输电线路发生烧断导线故障;在残锤的内绝缘被雨水渗浸后,其内绝缘水平低于外绝缘水平,闪络电弧从被雨水渗浸的残锤内绝缘导通,将有可能发生35 kV输电线路掉串故障。

基于压裂力筛选油菜抗裂角优异种质资源

油菜成熟后角果易开裂,导致收获损失率高,限制了产业的高质量发展。筛选抗裂角优异种质资源,对于培育抗裂角宜机收的油菜新品种具有重要意义。为了提高油菜抗裂角资源的筛选效率,本研究基于200份变异丰富的甘蓝型油菜种质资源,系统比较压裂法与随机碰撞法的鉴定结果,提出了一种基于压裂力的抗裂角高效鉴定方法。研究发现,基于随机碰撞法的抗裂角指数与基于压裂法的裂角力之间显著正相关,且压裂法比随机碰撞法重复性更好、效率更高、稳定性更强。基于抗裂角指数和裂角力之间的相关关系,制定了基于压裂力的抗性分级标准,最终基于压裂力筛选出5份高抗裂角的甘蓝型油菜优异种质资源。相关结果为进一步培育优质的油菜抗裂种质资源提供了高效的鉴定方法和重要的基因资源。

九寨沟强震区熊猫海—五花海段震裂山体发育特征及崩塌动力学分析

位于九寨沟世界遗产保护区内的熊猫海—五花海段危岩区,历经“5·12”汶川地震和“8·8”九寨沟强烈地震,崩塌落石频发,成为了控制性特大地质灾害点。该文通过现场调查、无人机测绘,查明了震后震裂山体(危岩)空间分布位置和崩塌落石堆积特征,并结合RocPro3D数值模拟,探讨了高位震裂山体(危岩)崩塌落石运动特征和危害程度。结果显示,熊猫海—五花海段震裂山体落石灾害频发,影响景区道路总长度约1045 m,且在长期差异性风化作用下,崩塌落石灾害危险性有逐渐增大的趋势。危岩Ⅳ区落石模拟结果得到,崩塌落石冲击能量和运动速度整体上呈现先增大后减小的特点,落石达到景区道路的最大冲击能量、弹跳高度和运动速度分别为8673kJ、11.63 m和53.8 m/s,其中WYD3到达块石数量占比最大,达到68.6%,落石直接到达日则沟的块石数量占比小,但平均能量达到1770kJ。基于震裂山体(危岩)分布高位陡坡、成灾动力学强、危害性大,提出以景区道路改为隧道方案,以确保景区运行安全。

中国环流三号多发破碎弹丸注入器初步工程设计

多发破碎弹丸系统是中国环流三号(HL-3)托卡马克装置开展破裂缓解实验研究的必备系统。依据HL-3装置的运行参数及物理需求开展了多发破碎弹丸注入器的初步工程设计。重点开展了弹丸基本参数的设计以及发射、破碎方式等选型,结合多发破碎弹丸注入器的系统设计及工艺布局,通过热力学分析对初步工程设计方案进行了确认。弹丸注入器的制备系统采用原位冷凝和气动加速的方式分别制备和发射共计三颗弹丸,弹丸尺寸分别为一颗Φ7 mm、两颗Φ5.5 mm,长径比为1.3,设计发射速度为200~300 m/s。

汶川强震区震裂山体分布特征与成灾模式研究

为研究2008年汶川8.0级地震强震区震裂山体灾害的分布特征及其成灾模式,首先基于植被退化趋势法和全球地表类型覆盖图等多源数据融合方法对研究区震裂山体进行识别,建立了124处典型震裂山体灾害点数据集。分析表明:震裂山体分布特征与地震的峰值加速度(PGA)等值线和断层距呈现高度正相关性,受高程放大效应和地形影响,85.48%的灾害点发育于泥石流沟域内,同时94.35%的震裂山体来源于同震滑坡后缘的持续变形;震裂山体主要成灾模式包括高位震裂山体高速崩滑碎屑流、高位震裂山体崩滑铲刮侵蚀型泥石流和高位震裂山体多点崩滑堵溃型泥石流三种灾害链。研究结果对强震区震裂山体灾害的全面识别和综合防治及强震区工程规划具有一定参考价值。

Study on Negative Effect Analysis of Mechanized Shattering and Returning for Sugarcane Leaf and its Control Technology

Soil structure and nutrient ingredient before and after shattering and returning sugarcane leaf as well as its technologies and methods were comparatively analyzed in this study to discuss the main reasons primarily,while the controlling technologies were proposed by combining cultivation,management and technical measures.

裸燕麦小花形态表型鉴定方法与落粒的形态学机制研究

落粒性是影响裸燕麦产量与品质的关键性状。本研究对228份具有代表性的裸燕麦材料的落粒性及小花的形态等15个性状进行田间多点鉴定,并建立了裸燕麦小花形态表型的鉴定方法。结果表明,15个性状在3个试验地点之间均表现出了不同程度的差异;裸燕麦的落粒性同内稃宽度(相关系数r=-0.36)、内稃面积(r=-0.30)、外稃宽度(r=-0.26)等9个性状呈显著或极显著负相关,与种子同内稃宽度的比值(r=0.37)及种子同外稃宽度的比值(r=0.20)呈极显著正相关,说明内外稃的宽度影响小花中种子的包裹程度,外稃厚度影响小花抵抗外力的能力,从而影响裸燕麦的落粒性。K-means聚类分析将参试材料分为两大类,Ⅰ类占整个群体的48%(110个),内稃和外稃整体上更加窄小,落粒性较高;Ⅱ类占群体的52%(118个),内稃和外稃整体上更加宽大,落粒性较低。对3个地点参试材料落粒性的密度分布进行了分析,提出了裸燕麦落粒性评价的等级划分标准:0~0.03为低落粒性,0.03~0.08为中落粒性,0.08~0.16为较高落粒性,0.16~0.23为高落粒性,大于0.23为极高落粒性。

童年期情感虐待与青少年网络攻击性行为的关系研究

为了探讨童年期情感虐待对青少年网络攻击性行为的影响,检验破碎世界假设在二者间的中介作用以及感知网络匿名性的调节效应,采用童年期情感虐待量表、破碎世界假设量表、感知网络匿名性量表和青少年网络攻击性行为量表对1230名青少年进行施测。研究结果表明:童年期情感虐待显著正向预测青少年网络攻击性行为;破碎世界假设在童年期情感虐待和青少年网络攻击性行为间起部分中介作用;感知网络匿名性在中介路径后半段“破碎世界假设→网络攻击性行为”中起调节作用,感知网络匿名性在直接路径“童年期情感虐待→网络攻击性行为”中起调节作用。建议通过降低青少年童年期情感虐待、加强家庭情感温暖建设和降低感知网络匿名性,帮助青少年树立积极的世界假设来减少其网络攻击性行为,促进其健全人格的建立,提高其心理健康水平。

隧道洞渣加工混凝土在其结构工程中的应用

为研究石灰岩洞渣作为骨料应用于混凝土中是否具有应用价值,以青峰岭隧道为依托工程,通过分析隧道地层岩性,以岩石单轴饱和抗压强度为依据,确定隧道洞渣具备加工的可行性,并选取合适的洞渣强度快速评价标准与适配的加工工艺生产出质量优良的集料,并成功应用于隧道结构实体。通过隧道洞渣加工混凝土,隧道共产出约8万t集料,资源利用化率达到30%,为后续的洞渣利用提供了一定的借鉴经验。

After Effects中Shatter(碎片)滤镜的使用方法与实践

在影视作品包装中,破碎效果这个特效非常重要,也是非常常用。制作爆炸的软件有很多,本文利用在After Effects中自带滤镜Shatter制作出相对真实的爆炸效果,来了解Shatter的基本功能。

Combining Ability and Breeding Potential of Rapeseed Elite Lines for Pod Shatter Resistance

Pod shatter resistance of rapeseed is of great importance for modem farming practice. In order to determine the combining ability of elite inbred lines and the breeding potential of rapeseed hybrids in terms of pod shatter resistance, analysis of a 6×6 incomplete diallel cross was conducted at two locations. Results showed that a significant variation existed among breeding lines and their F1 hybrids for pod shatter resistant index （SRI）, pod length and width. Pod shatter resistance was significantly positively correlated with pod length. The general combining ability （GCA） effects （GCA=l.58） played a more important role than specific combining ability （SCA） effects （SCA=0.20） for pod shatter trait. The elite lines R1, 1019B and 1055B displayed significant positive GCA effects for pod shatter resistance. Four crosses （1019B×R1, 1015B×R1, 6098B×R1, and 8908B×R1） with high mean performance and positive SCA effects were recommended for developing new hybrids for mechanical harvest in the middle reaches of the Yangtze River.

Effects of paclobutrazol on biomass production in relation to resistance to lodging and pod shattering in Brassica napus L.

Paclobutrazol was sprayed at 0, 150, and 300 mg L-1 during the closed canopy stage and the early bud stage with two high-yielding cultivars of rapeseed, Yangguang 2009 and Fengyou 520. The impact of paclobutrazol on the accumulation and distribution of biomass and its relationship with yield, resistance to lodging and pod shattering were determined. All the treatments increased the resistance as well as yield. The maximum yield was obtained when paclobutrazol was applied during the closed canopy stage at 150 mg L-1. The plant＇s resistance to both lodging and pod shattering was the maximum when paclobutrazol was applied during the early bud stage at 300 mg L-1. Paclobutrazol also delayed senescence, with the higher concentration or later spraying leading to more obvious effects; improved the net assimilation rate before the early bud stage; and promoted the relative growth rate of the main growth organ at each stage of growth and maximized the rate and quantities of biomass accumulation. However, at the higher concentration and later spraying, the increments were smaller. The spraying also increased the rates of biomass allocation to roots, leaves, and pods, but the rate of allocation to stems decreased as the plants grew shorter. The higher allocation to roots and the lower allocation to stems favoured resistance to both lodging and pod shattering whereas higher allocation to leaves and pods favoured yield. The higher concentration or late spraying led to excessive biomass being allocated to roots, which decreased leaf biomass during the bud stage, leading to greater resistance but lower yields.

A lignified-layer bridge controlled by a single recessive gene is associated with high pod-shatter resistance in Brassica napus L.

Pod shattering causes severe yield loss in rapeseed(Brassica napus L.)under modern agricultural practice.Identification of highly shatter-resistant germplasm is desirable for the development of rapeseed cultivars for mechanical harvesting.In the present study,an elite line OR88 with strong shatter resistance and a lignified-layer bridge(LLB)structure was identified.The LLB structure was unique to OR88 and co-segregated with high pod-shatter resistance.The LLB structure is differentiated at stage 12 of gynoecium development without any gynoecium defects.Genetic analysis showed that LLB is controlled by a single recessive gene.By BSA-Seq and map-based cloning,the resistance gene location was delimited to a0.688 Mb region on chromosome C09.Transcriptome analysis suggested Bn TCP8.C09 as the gene responsible for LLB.The expression of Bn TCP.C09 was strongly downregulated in OR88,suppressing cell proliferation in the pod valve margin.KASP markers linked to the candidate gene were developed.This pod shatter-resistant line could be used in rapeseed breeding programs by direct transfer of the gene with the assistance of the DNA markers.

Effects of Planting and Maturity Dates on Shattering Patterns under Early Soybean Production System

Seed shattering is a common problem in early soybean production system (ESPS) in the Midsouth, which mainly uses maturity group (MG) IV soybeans. Many studies have been conducted on the genetics of soybean shattering resistance for individual varieties;however, information on the physiology of soybean shattering pattern under specific environmental conditions, which is often critical to soybean growers, is very limited. Field experiments were conducted at Stoneville MS from 2007 to 2009 to investigate the shattering patterns of 80-132 MG IV soybean varieties each year. Results from 2007 and 2008 indicated that, when April-planted MG IV soybeans matured in mid- to late August, pods of most soybean varieties did not shatter within the first three weeks after maturity (WAM) and there was no significant shattering effect on final yields. However, differences in pod shattering among the varieties became apparent in the fourth WAM. Late-planted MG IV soybeans, which matured in early September, had a low shattering rate and could hold seeds up to 6 WAM before reaching a critical shattering point. Most soybean varieties planted in April 2009 did not show significant pod shattering by the end of the fourth WAM. The critical point of shattering was not reached until 6 - 7 WAM. Relatively lower temperatures and abundant rainfall during the late growing season in 2009 may be the main reasons causing delayed shattering in April-planted MG IV soybeans. Results from the May-planting of 2007 and the April-planting of 2009 indicated that soybeans maturing after September have much less problematic shattering. Different weather patterns, especially temperature and rainfall in each year could be essential factors affecting seed shattering patterns.

Formation Mechanism and Occurrence Law of Pod Shattering in Soybean:A Review

Seed shattering refers to the phenomenon in which the pods split along the abdominal and back sutures before the crop is received,so that the seeds are spread.Seed shattering is vital to the reproduction of their offspring in wild plants,but it is also the main cause of crop yield loss reason.Pod-explosion resistance is a complex process of physical and physiological and biochemical reactions.Soybean seed shattering phenomenon is widespread,which severely restricts the development of soybean industry.Seed shattering(pod cracking or fruit dropping)is essential for the reproduction of its offspring in wild plants,but it is also the main cause of crop yield loss.This article analyzes the morphology and structure of pods related to seed shattering from the morphology of pods.On the basis of the regularity of the occurrence of seed shattering and the summary of phenotypic index identification methods,physiologically introduced the regulation mechanism of key enzymes and endogenous hormones on seed shattering.The localization,labeling and cloning of seed shattering genes are introduced in molecular biology.The study focused on reviewing the latest advances in the research on soybean seed shattering characteristics,and discussed with the research results of related crops.Finally,the research and application of soybean seed shattering resistance were prospected for several aspects.

Use of A Shatter Test Vessel to Assess Propellant Safety

At low temperatures,gun propellant grains may become brittle and this can lead to fracture or shatter of the grains during gun firing.Should this event occur then it will result in an increase in the burning surface of the propellant and will give rise to a change in ballistic performance.Also,if the resultant over pressure is sufficient,a breech failure may result.Understanding the propensity of a grain to fracture or shatter is therefore important in determining its safety in use.This document describes a test that may be used to derive knowledge and to quantify the physical behaviour of a gun propellant grain at the low temperatures at which fracture or shatter is most likely to occur.

Mutagenic Improvement of Shattering Characteristic of the Restorer Line of a Hybrid Rice“Xieyou 9308”

The newly developed hybrid rice combination 'Xieyou 9308' (Xieqingzao A/T9308) has been regarded as a super-high-yielding rice variety, of which the yield potential reached as high as 12 t/ha. However, its high shattering characteristic (as high as 60%) has limited its wider application. In the current experiment, a non-shattering mutant line, M9308, was developed from T9308 by gamma irradiation. Comparisons were made but no marked differences were found between T9308 and M9308 as well as between their F1 hybrids crossed to Xieqingzao A for major agronomic and grain quality characters as well as resistance to diseases. Genetic analysis indicated that the non-shattering character of M9308 was governed by a single recessive gene.

Identification and validation of stable and novel quantitative trait loci for pod shattering in soybean[Glycine max(L.)Merr.]

Pod shattering is an important domesticated trait which can cause great economic loss of crop yield in cultivated soybean.In this study,we utilized two recombinant inbred line populations(RILs,CY,Huachun 2×Wayao;GB,Guizao 1×B13)to identify quantitative trait loci(QTLs)associated with pod shattering in soybean across multiple environments.A total of 14 QTLs for pod shattering were identified in the two RIL populations,which had LOD scores ranging from 2.64 to 44.33 with phenotypic variance explanation(PVE)ranging from 1.33 to 50.85%.One QTL qPS16-1,located on chromosome 16,included a well-known functional gene Pod dehiscence 1(Pdh1)that was reported previously.Ten new putative QTLs were validated in two RIL populations,and their LOD scores were between 2.55 and 4.24,explaining 1.33 to 2.60%of the phenotypic variation.Of which four novel QTLs(qPS01-1,qPS03-2,qPS05-1,and qPS07-1)could be detected in two environments where nine genes had specific changes in gene expression.Although the nine genes may have significant effects on pod shattering of soybean,their detailed functions still need to be further explored in the future.The results of this study will facilitate a better understanding of the genetic basis of the pod shattering-resistant trait and benefit soybean molecular breeding for improving pod shattering resistance.