Ethephon Effect on Peanut Seed Dormancy Release

Dormancy is undesirable character for the peanut seed(Arachis hypogeae).KK 84-7 and KK 6 varieties are characterized to the Virginia type and its dormant period has been one to two months after harvest.The recommendation for breaking peanut seed dormancy by the International Seed Testing Association(ISTA)rules is preheat at 40°C up to 168 h.The total germination test is 17 d,if breaking dormant seed is required.Effect of ethephon on peanut seed dormancy release was studied in this experiment to reduce the analysis time compared to preheat method.Both varieties of peanut seeds were directly mixed with 0.96%ethephon and preheated at 40°C for 168 h.Standard germinations were conducted for all treated and untreated seeds.Ethephon was the most beneficial to release dormant seed at fresh harvest that achieved 86%and 84%normal seedlings for KK 84-7 and KK 6,respectively.The normal seedlings of preheat treatment showed 75%for KK 84-7,and 66%for KK 6.Only 6%normal seedlings were observed in untreated seeds of KK 84-7 and 56%of KK 6.After storage at 20°C for 28 d,KK 84-7 had over 90%normal seedlings with both ethephon and preheat methods,but only 42%germination was observed in untreated seeds.In KK 6,the highest germination by 90%was found in ethephon,followed by untreated and preheated seeds that were 87%and 83%,respectively.The paired t test of normal seedlings between ethephon and preheat treatments demonstrated that the greater average germination was found in ethephon method for both varieties.This research suggests that ethephon is the advantageous method for breaking peanut seed dormancy.The germination test duration is more rapid,only 10 d,since preheat for 168 h is not necessary.

Use of Unmanned Aerial System (UAS) Phenotyping to Predict Pod and Seed Yield in Organic Peanuts

Peanut (Arachis hypogaea L.) is a highly nutritious food that is an excellent source of protein and is associated with increased coronary health, lower risk of type-2 diabetes, lower risk of breast cancer and a healthy profile of inflammatory biomarkers. The domestic demand for organic peanuts has significantly increased, requiring new breeding efforts to develop peanut varieties adapted to the organic farming system. The use of unmanned aerial system (UAS) has gained scientific attention because of the ability to generate high-throughput phenotypic data. However, it has not been fully investigated for phenotyping agronomic traits of organic peanuts. Peanuts are beneficial for cardio system protection and are widely used. Within the U.S., peanuts are grown in 11 states on roughly 600,000 hectares and averaging 4500 kg/ha. This study’s objective was to test the accuracy of UAS data in the phenotyping pod and seed yield of organic peanuts. UAS data was collected from a field plot with 20 Spanish peanut breeding lines on July 07, 2021 and September 27, 2021. The study was a randomized complete block design (RCBD) with 3 blocks. Twenty-five vegetation indices (VIs) were calculated. The analysis of variance showed significant genotypic effects on all 25 vegetation indices for both flights (p < 0.05). The vegetation index Red edge (RE) from the first flight was the most significantly correlated with both pod (r = 0.44) and seed yield (r = 0.64). These results can be used to further advance organic peanut breeding efforts with high-throughput data collection.

Effect of Trace Elements in Seed Coating Agent on Peanut Growth

[Objective] This study aimed to investigate the effect of trace elements in peanut seed coating agent. [Method] Different concentrations of trace elements Fe and B were added into peanut coating agent, then the germination rate and plant height of the seeds treated by different agents were measured to decide the best formula. [Result] The germination rate and plant height of the seeds treated with seed coating agent was obviously increased. Adding trace elements Fe and B could increase the peanut yield, and 1.5% Fe and 1% B gave the best result. [Conclusion] This study will provide reference for modifying the seed coating agent formula.

DOF transcription factors in developing peanut (<i>Arachis hypogaea</i>) seeds

DNA binding with one finger (DOF) transcription factors play important roles in storage material accumulation and morphogenesis of developing seeds. Oil and protein contents varied in different cultivars in important oil crop peanut. DOF proteins have not been studied in this crop. In this paper, we analyzed all the DOF genes expressed in developing seeds from a cDNA library with 20,000 transcripts, cloned and compared similar genes of GW391729 from eight peanut cultivars, and analyzed similar genes expressed in root and leave with control and inoculated with Ralstonia solanacearum. The results indicate that total eight types of DOF genes were expressed in developing seeds of cultivar 063103. Most of DOF transcription factors expressed involved in developmental process in a complicated way. Among them, GW391729 is possible related to the seed number in fruit, and also is possible related to leafspot resistance. Detailed function of these DOF proteins need to be further studied.

Identification of major QTL for seed number per pod on chromosome A05 of tetraploid peanut(Arachis hypogaea L.)

The inheritance of pod-and seed-number traits(PSNT) in peanut(Arachis hypogaea L.) is poorly understood. In the present study, a recombinant inbred line(RIL) population of 188 lines was used to map quantitative trait loci(QTL) for number of seeds per pod(NSP),number of pods per plant(NPP), and numbers of one-, two-, and three-seeded pods per plant(N1 PP, N2 PP, and N3 PP) in four environments. A total of 28 consensus QTL and 14 single QTL were identified, including 11 major and stable QTL. Four major and stable QTL including qN3 PPA5.2, q N3 PPA5.4, qN3 PPA5.5, and qN3 PPA5.7 each explained 12.3%–33.0% of phenotype variation. By use of another integrated linkage map for the A5 group(hereafter referred to as INT A5 group), QTL for PSNT were located in seven intervals of 0.73–9.68 Mb in length on chromosome A05, and candidate genes underlying N3 PP were suggested. These findings shed light on the genetic basis of PSNT. Major QTL for N3 PP could be used as candidates for further positional cloning.

Simple and Efficient Cultivation Technology for the Peanut under the Standardization Mode of Single-seed Sowing

Single-seed sowing is a new,simple and efficient cultivation mode for peanut that realized from cultivation of healthy individual and construction of high-yielding population. The cultivation mode has the obvious advantages in uniform seedling,strong sprouting,seed saving and cost saving,thus it is considered as one of the effective ways for high-yield and high-efficient peanut cultivation in China in the future.Through integrating with other high-efficiency and simple cultivation measures,the single-seed sowing technology system has made conforming to China's national standardization cultivations of peanut and the technology was already applied in the main producing areas of peanut and gained the significant efficiency and abroad application prospects. Based on many years of researches in single-seed sowing technology,high-efficiency fertilization and scientific chemical control in the research team,by combining with the latest research results in plant protection and machinery,this paper described the key points and matters needing attentions from variety selection,planting mode,rational fertilization,planting specifications and field management.

Research of Seed Testa Structure and Storage Material of Peanut Germplasm with Different Resistance to A. flavus

There was an obvious relationship between seed testa structure, storage material and resistance to A. flavus of peanut. Results showed that seed testa of peanut germplasm with high resistance （HR） to A. flavus infection had thicker wax layer, integrated and tight epidermis layer, regular vascular tissue range. However, the seed testa of peanut germplasm with high sensitivity （HS） to A. flavus had the reverse results, and results of those with medium resistance （MR） to A. flavus lay in between, but changes of testa thickness were not significant among different resistance kinds. Results also showed that some seed storage materials were closely related with resistance potential to A. flavus. It seemed that varieties with higher resistance to A. flavus had higher oleic acid and protein content, lower linoleic acid and fat content. Content of palm acid, total sugar and VE did not show positive relationship with the resistance to A. flavus.

栽培花生籽仁面积和周长性状的QTL定位分析

籽仁面积和周长是影响花生籽仁大小和外观的重要性状。本研究以‘鲁花11号’ב06B16’构建的重组自交系(recombinant inbred line,RIL)群体为试验材料,对花生籽仁面积和籽仁周长在4个环境进行性状考察及QTL定位分析。基于表型数据和高密度遗传图谱信息,在A04和B06染色体上定位到15个与籽仁面积和籽仁周长性状相关的QTL,其中8个与籽仁面积相关,7个与籽仁周长相关。控制籽仁面积和周长的主效位点qSAB06.1d和qSPB06a在多个不同环境均能检测到,表型贡献率为9.52%~33.78%,其增效等位基因均来自鲁花11号,共定位在B06染色体138.53~140.76 Mb区域内。对主效位点qSAB06.1d/qSPB06a进行功能注释,鉴定到3个编码转运蛋白、1个编码ABA受体PYL和1个编码钙调磷酸酶的基因,它们可能是调控花生籽仁面积和周长的候选基因。本研究将为花生产量和外观性状的精细定位和遗传改良奠定理论基础。

不同密度单粒精播对花生开花动态及结实特性的影响

为探讨不同密度单粒精播对花生开花动态及结实特性的影响,以普通大花生品种花育25为材料,在行距相同的条件下设置4个处理,包括单粒播分别为株距9 cm、12 cm和15 cm,折合播种密度分别为27.8万株·hm^(-2)(S9)、20.8万株·hm^(-2)(S12)和16.7万株hm-2(S15)3个处理,和双粒播27.8万株·hm^(-2)(D18,穴距18 cm)1个处理,研究不同密度单粒精播对花生开花习性、果针形成、荚果发育动态、结实范围及产量的影响。结果表明,与双粒播相比,不同密度单粒播均可不同程度地促进花生早开花、多开花,增加有效果针数,促进荚果发育,低密度条件下,效果最为显著;从群体指标看,20.8万株·hm^(-2)的单粒精播模式下,花生开花数、有效果针数、结果数最多,荚果体积最大,荚果饱满度高,产量水平最高。不同密度单粒精播改变了花生的结实范围和荚果空间分布,密度降低,结实范围增加,但不同处理荚果干重(95%以上)仍主要分布在半径6.0 cm以内的空间范围内,密度20.8万株·hm^(-2)(株距12.0 cm)的单粒精播条件下,结实范围与半株距接近,更有利于群体间荚果的均匀分布。

花生高产攻关实收单产12982 kg/hm^(2)技术分析

为进一步挖掘花生高产潜力,示范带动大面积单产提升,自2013年开始山东省农业科学院花生栽培与生理生态创新团队连续组织高产攻关,产量相继突破实收单产11250 kg/hm^(2)、11700 kg/hm^(2)、12000 kg/hm^(2),其中2023年最高产达到12982 kg/hm^(2)。本文从栽培技术、气候条件、产量构成等方面分析了高产纪录产生原因,并对投入、产出进行了比较。栽培技术方面,集成应用了单粒精播、全程可控施肥、生物菌剂耦合、三防三促调控的高产栽培技术体系,通过充分发挥单株生产潜力、构建高质量群体来实现高产,为下一步单产突破13500 kg/hm^(2)提供技术支撑。

种衣剂处理对低温胁迫下花生种子萌发及幼苗生长和生理特性的影响

花生播种期易受低温胁迫,为明确种衣剂处理对低温胁迫下花生种子萌发、幼苗生长和生理特性的影响,以常温(25℃)处理为对照(CK),设8℃和10℃两个低温胁迫处理,各温度下设种衣剂包衣和清水浸润对照两种处理方式,研究种衣剂处理对低温胁迫下花生种子活力、幼苗干物质积累、根系形态特征和光合生理的影响。结果表明,相对于常温处理,8℃低温胁迫处理显著降低了花生种子发芽势(5.9%)、发芽率(7.7%)、发芽指数(11.0%)、种子活力指数(6.9%)和幼苗叶片SPAD值(11.4%),同时对幼苗根系生长产生抑制作用,其根长、根表面积和根体积较25℃常温和10℃低温胁迫处理分别显著降低50.0%~50.2%、44.9%~48.1%、48.2%~48.5%,但8℃低温胁迫处理对花生幼苗地上部和地下部干物质积累、最大光化学效率及胞间二氧化碳浓度、气孔导度、净光合速率和蒸腾速率等光合参数均无显著影响;种衣剂处理显著提高了8℃低温胁迫下花生种子的发芽势(8.2%)、活力指数(10.9%)和花生幼苗根长(45.1%)及根表面积(38.4%),但对10℃低温胁迫和常温处理均无显著影响,同时,种衣剂处理还显著提高了常温处理下花生幼苗干物质积累、最大光化学效率和功能叶片光合特性以及10℃低温下地上部干物质积累和最大光化学效率,但对8℃低温胁迫无显著作用。综上,花生种子萌发和幼苗根系生长对低温胁迫的响应更加显著,而种衣剂处理可以通过改善上述指标缓解低温胁迫,改善轻度低温胁迫和常温处理下花生幼苗生长的干物质积累和光合生理。

单粒精播对花生干物质累积及根冠结构的影响

为明确花生单粒精播增产机理,大田条件下,以花育22为供试花生品种,以双粒穴播(DS)为对照,研究了单粒精播(SS)对花生干物质积累、叶面积系数、冠层结构和根系特征的影响。结果表明,花生生育前期单株和群体干物质重单粒精播和双粒穴播差异不显著,而生育中后期显著高于双粒穴播,结荚期叶面积系数单粒精播显著高于双粒穴播。从结荚期不同冠层结构来看,冠层上、中、下层叶面积系数单粒精播分别比双粒穴播高23.03%、9.34%、86.43%,单株和群体冠层叶片和茎干重单粒精播均显著高于双粒穴播,从冠层不同部位叶片和茎干重占总干重的比例来看,单粒精播冠层下部叶片和茎干重比例高;单株和群体总根干重、根长、根表面积和根体积高于双粒穴播,且中下层根系占比高。相关性分析结果表明,根干重与中下层的叶片干重、下层的茎干重呈显著正相关。综上所述,与双粒播相比,单粒精播花生植株冠层中下部发育健壮且根系大分布深是其增产的重要原因。单粒精播促根扩冠,是花生节本增产的一种有效途径。

花生小区播种施肥机设计与试验研究

我国花生育种小区机械化程度低,播种收获等关键环节仍以人工作业为主,劳动强度大,效率低,且易出现混种问题。为此,结合我国花生育种小区种植的农艺要求,设计了多功能花生小区播种施肥机,适宜垄作覆膜的种植模式。其在传统窝眼轮式排种器上加设净种装置,能够清除窝眼轮内剩余的种子,保证了育种小区试验的科学性;创新设计了起垄装置与覆膜装置,能够一次性完成开沟、施肥、起垄、播种及覆膜等多项作业,提高了播种机的效率。试验结果表明:机具作业后花生双粒率为99.16%,漏播率为0.6%,穴距偏差率为12.03%,重播率为0.91%,种子覆土深度合格率为90.32%,排种器清种率为100%,种子出苗率为80.90%,作业质量符合我国花生小区种植的农艺要求。该播种机的使用,提高了花生育种小区种植作业效率,为小区后续作业实施机械化提供了便利,可为育种小区机械的研发提供参考。

锰肥和锌肥种子包衣对花生的降镉效果

花生对土壤中的镉(Cd)具有较强的富集能力,我国花生Cd超标现象局部地区较为严重,Mn、Zn离子可通过拮抗作用降低作物对Cd的吸收,本研究探究Mn肥、Zn肥种子包衣处理对花生Cd吸收转运的影响,以期为花生产地土壤Cd污染风险管控与修复提供技术支撑。首先通过种子萌发试验筛选出3个锰(Mn)和锌(Zn)较适宜的包衣剂浓度,再进一步通过盆栽试验筛选出降镉效果最优的Mn和Zn包衣剂浓度,并探究了Mn肥和Zn肥种子包衣对Cd污染土壤上花生富集转运Cd的影响。种子萌发试验结果表明,中低浓度的Mn肥、Zn肥种子包衣处理不会影响种子发芽率且可以促进根生长,浓度过高则会明显抑制种子萌发。盆栽试验结果表明,Mn肥和Zn肥种子包衣剂中,3%锰肥包衣剂(Mn3)和2%锌肥包衣剂(Zn2)包衣处理籽粒降镉效果最显著,降镉率分别达到19.0%和24.1%,其中Zn2降镉效果更优。与对照相比,Mn3和Zn2处理根系Cd富集系数均显著降低,根向茎叶Cd转运能力明显增加,茎叶向籽粒Cd转运系数呈下降趋势,根系向籽粒Cd转运系数则无明显变化。Mn3和Zn2处理花生植株总Cd吸收量相比对照分别下降了9.18%和13.6%,花生籽粒及根系Cd含量均与根系中Mn、Zn元素含量呈显著负相关关系。综上,利用Mn、Zn种子包衣处理可通过抑制根系对Cd的吸收以及影响Cd在花生体内的转运来降低花生籽粒Cd含量。本研究提出了利用种子包衣来降低花生Cd含量的技术,为花生产地镉污染风险管控提供了新方法。

外源褪黑素对旱胁迫下花生种子萌发及抗性的影响

本研究旨在探索外源褪黑素对干旱胁迫下花生种子萌发及抗性的影响。以干旱敏感型花生品种‘冀花5号’为试验材料,通过筛选种子萌发其适宜的PEG和褪黑素浓度,并设置空白水浸种(CK),褪黑素浸种(T_(1)),10%PEG-6000处理(T_(2))和褪黑素浸种加10%PEG-6000处理(T_(3))等4种处理,于种子萌发后进行抗氧化生理生化指标的测定。研究结果显示,模拟干旱的PEG-6000浓度为10%时,可以模拟干旱环境。同时,100µmol/L的褪黑素浓度是促进花生种子萌发的最佳选择。进一步分析各处理花生种子胚根长度与粗度和抗氧化生理生化指标,发现干旱胁迫下施用100µmol/L的褪黑素处理显著增强胚根生长势,并显著提高种子内SOD、POD和Pro的含量,且有效降低种子内MDA和H_(2)O_(2)的含量。综上所述,本研究表明外源褪黑素可以有效提高干旱胁迫下花生种子的萌发,为进一步探究干旱胁迫下褪黑素促进花生种子萌发的调控机制提供了理论依据。

不同类型花生浸种过程物理特性变化及内部水分迁移规律

探究高油酸、高蛋白和普通花生在不同温度(25℃和31℃)和浸泡时间(0、3、6、9、12 h)下的浸种特性,利用低场核磁共振成像技术动态监测种子水分相态和迁移,明确不同类型花生种子浸种过程的物理特性变化和吸水动态,旨在探寻不同类型花生适宜的浸种时间和温度,降低花生萌发时种皮破损率。结果表明,不同温度和浸泡时间处理下,3种类型花生种子的质量增加率、体积增加率、含水率增加率及总信号幅值等与花生浸泡时间和温度呈显著正相关(P<0.05)。高蛋白花生YH9326的蛋白质与高蛋白标准比值(P/P标)最高(1.37),在25℃浸种12 h后质量增加率最高(58.91%),与31℃处理无显著差异;25℃下浸种3、6 h含水率增加率较31℃分别下降22%、6%;2种温度下非结合水信号幅值增加率在浸种12 h显著高于浸种9 h,显示出种子持续吸水状态;与31℃浸种相比,25℃下浸种3 h总水和结合水信号幅值增加率分别提高42%和10.0倍。普通花生HY38的油酸与亚油酸比值(OA/LA)最低(1.30),31℃浸种3、6、9 h后,其体积增加率显著提高,分别较25℃浸种时提高8%、17%、25%;浸种9 h后含水率增加率比25℃提高20%;浸种3、6 h,其结合水信号幅值增加率较25℃分别下降35%和29%,但非结合水信号幅值增加率显著提高99%和55%;在31℃浸种6、9 h,非结合水信号幅值增加率无显著差异。高油酸花生YH37的油酸与亚油酸比值(OA/LA)最高(11.1),在25℃下浸种3 h体积增加率(46.13%)高于YH9326和HY38,相较于31℃浸种3、6 h后,其非结合水信号幅值增加率分别降低13%、9%,结合水信号幅值增加率显著提高3.5倍和1.3倍。在25℃浸种,高油酸花生YH37和高蛋白花生YH9326的非结合水信号幅值增加率虽表现持续吸水到浸种12 h,但在浸种6、9 h无显著差异。高蛋白花生YH9326及高油酸花生YH37适宜在25℃浸种6 h,可完成初始快速吸胀吸水;普通花生种子HY38适宜31℃浸种6 h,基本完成初始快速吸胀吸水。

LEC1等转录因子基因在花生小种子突变体种子发育过程中的表达分析

花生突变体ssm1与其对照亲本鲁花11号(LH11)相比,种子皱缩变小,百仁重、单株生产力和含油量显著降低。为了探究导致该突变体种子变小且含油量降低的原因,本试验研究了种子发育关键转录因子基因LCE1等在突变体ssm1及其对照LH11合子受精及种子发育不同阶段的表达情况。结果表明,AhLEC1在花生未受精子房(DBP0)时期表达量较低,且在ssm1和对照LH11中无明显差异,在受精后的子房(DBP1)和入土10 d(DAP10)和20 d(DAP20)种子中表达量上调,并且在LH11中的表达量极显著高于突变体ssm1;转录因子基因AhFUS3、AhABI3、AhAGL15和AhWRI1在ssm1中表达均有不同程度下调。其中,与脂肪酸合成和糖酵解关系密切的AhWRI1基因在ssm1中的表达量显著下调。因此推测,ssm1中AhLEC1基因的表达量显著下调,影响AhFUS3、AhABI3和AhWRI1等基因的表达,进而导致ssm1种子胚胎发育和油脂积累的异常。

1979—2019年中国5种主要油料作物的时空分布变化

旨在为挖掘油料作物增产潜力、提升油料产能、保障国内食用植物油供给安全等政策制定提供参考,通过集中度和比较优势分析,研究了1979—2019年我国5种主要油料作物(花生、油菜、向日葵、芝麻和胡麻)的时空分布变化。结果显示:1979—2019年花生种植集中度呈减小趋势,油菜和胡麻集中度升高,向日葵和芝麻集中度则先降低后升高;2019年河南、山东、广东、辽宁、河北5省花生综合优势指数大于1,其中河南为我国花生第一生产大省,综合优势指数从0.80增加至1.93;湖南、四川、湖北、贵州、安徽5省具有稳定的油菜生产综合优势,2019年川渝地区(四川和重庆)、湖北、湖南油菜籽产量居前三位;1979—2019年内蒙古和新疆向日葵综合优势指数分别为2.14~3.38和1.64~3.06,且在2019年它们分别是我国葵花籽生产第一、第二大主产地;河南、湖北两省一直是我国芝麻生产核心区域,综合优势指数分别为1.50~2.13和2.17~2.39;甘肃、宁夏、山西、内蒙古具有胡麻生产综合优势,2019年甘肃、内蒙古和宁夏胡麻籽产量居前三位。综上,当前河南、川渝地区、内蒙古、甘肃分别是我国花生(和芝麻)、油菜籽、葵花籽、胡麻籽等核心油料生产区域。

幼苗期不同花生品种的耐渍性评价

为研究我国常栽花生品种耐渍性差异,在幼苗期通过盆栽试验,以正常水分为对照,设置48 h渍水胁迫处理,测定不同品种的SPAD值、根长、株高、根生物量等相关指标,明确不同花生品种间苗期的耐渍差异,从而筛选出耐渍性差异显著的花生品种。结果表明:渍水胁迫对花生幼苗期的形态建成有不同程度的抑制效应。与对照组相比,渍水条件下的花生根系鲜质量、地上部鲜质量、根系生物量、地上部生物量、植株生物量分别下降52.24%、45.43%、54.22%、37.84%、41.81%;地上部各项形态指标的平均变异系数为32.48,而根部各形态指标的平均变异系数达38.62;以根系鲜质量、植株鲜质量、根长、株高、SPAD值等指标的相对值作为花生耐渍性评价的指标进行聚类分析,将本研究的16个花生品种分为较强耐渍性、较弱耐渍性两类。研究结果为深入研究花生品种的耐渍机制及培育耐渍品种提供理论依据。

气力辅助充种式花生精量排种器设计与试验

针对花生播种向精准、高速方向发展过程中高速作业状态下花生种子充种效果差的问题,设计了一种气力辅助充种式花生精量排种器,重点设计了排种器排种盘结构和气力辅助充种结构。针对颗粒尺寸大、质量大的花生种子,通过对花生种子在排种器中堆积现象与充种时间进行分析,得出花生高速排种充种过程需增强充种性能,从而提高充种效率。通过对花生种子进行充种原理分析,阐明花生种子充种过程中种子与排种器的运动关系与受力关系,分析充种过程影响因素。通过设计带有导种槽的排种盘和带有辅助吹种型孔的辅助充种结构,分析计算排种盘吸种孔、导种槽的关键结构参数以及辅助吹种型孔参数与排列方式。以充种合格率和充种漏充率为指标,进行三因素三水平组合试验,对试验结果进行多元回归分析,以最优目标进行优化,确定排种盘最佳参数组合为排种器吸种负压5.156 kPa、花生高速播种机前进速度8.007 km/h、扰动吹种正压1.149 kPa,此时,花生充种合格率为95.84%、漏充率为4.06%,能够实现花生种子有效充种。