Construction of Genetic Linkage Map Based on SSR Markers in Peanut(Arachis hypogaea L.)

Molecular genetic maps of crop species can be used in a variety of ways in breeding and genomic research such as identification and mapping of genes and quantitative trait loci （QTLs） for morphological, physiological and economic traits of crop species. However, a comprehensive genetic linkage map for cultivated peanut has not yet been developed due to the extremely low frequency of DNA polymorphism in cultivated peanut. In this study, 142 recombinant inbred lines （RILs） derived from a cross between Yueyou 13 and Zhenzhuhei were used as mapping population in peanut （Arachis hypogaea L.）. A total 652 pairs of genomic-SSR primer and 392 pairs of EST-SSR primer were used to detect the polymorphisms between the two parents. 141 SSR primer pairs, 127 genomic-SSR and 14 EST-SSR ones, which can be used to detect polymorphisms between the two parents, were selected to analyze the RILs population. Thus, a linkage genetic map which consists of 131 SSR loci in 20 linkage groups, with a coverage of 679 cM and an average of 6.12 cM of inter-maker distance was constructed. The putative functions of 12 EST-SSR markers located on the map were analyzed. Eleven showed homology to gene sequences deposited in GenBank. This is the first report of construction of a comprehensive genetic map with SSR markers in peanut （Arachis hypogaea L.）. The map presented here will provide a genetic framework for mapping the qualitative and quantitative trait in peanut.

Functional Analysis of the Phosphoenolpyruvate Carboxylase on the Lipid Accumulation of Peanut(Arachis hypogaea L.) Seeds

Phosphoenolpyruvate carboxylase（PEPC;EC 4.1.1.31） catalyses phosphoenolpyruvate（PEP） to yield oxaloacetate,which is involved in protein biosynthesis.Pyruvate kinase（PK;EC 2.7.1.40） catalyzes PEP to yield pyruvate,which is involved in fatty acid synthesis.In this study,five PEPC genes（AhPEPC1,AhPEPC2,AhPEPC3,AhPEPC4,and AhPEPC5） from peanut have been cloned.Using a quantitative real-time RT-PCR approach,the expression pattern of each gene was monitored during the seed development of four peanut varieties（E11,Hebeigaoyou,Naihan 1,and Huayu 26）.It was found that these five genes shared similar expression behaviors over the developmental stages of E11 with high expression levels at 30 and 40 d after pegging（DAP）;whereas these five genes showed irregular expression patterns during the seed development of Hebeigaoyou.In Naihan 1 and Huayu 26,the expression levels of the five genes remained relatively high in the first stage.The PEPC activity was monitored during the seed development of four peanut varieties and seed oil content was also characterized during whole period of seed development.The PEPC activity followed the oil accumulation pattern during the early stages of development but they showed a significantly negative correlation thereafter.These results suggested that PEPC may play an important role in lipid accumulation during the seed development of four peanut varieties tested.

Drought-induced responses of organic osmolytes and proline metabolism during pre-flowering stage in leaves of peanut (Arachis hypogaea L.)

Peanut （Arachis hypogaea L.）, an improtant oil crop, usually encounters drought stress in the process of growth and development, especially at pre-flowering stage. In order to gain insight into the drought tolerance potentials based on osmolyte accumulation and metabolism of proline aspects of peanut, pot experiments were conducted with a split-plot design in Tai＇an, Shangdong Province, China in 2013 and 2014. Pre-flowering drought （PFD） stress and optinum irrigation （control, CK） were served as the main plots and the two peanut cultivars Shanhua 11 and Hua 17 served as sub-plots. Shanhua 11 was drought-tolerant cultivar and Hua 17 was drought-sensitive. The content of soluble sugars, soluble protein, free proline and other free amino acids, the activities of enzymes involved in proline metabolism, and malondialdehyde （MDA） content and ion leakage were all investigated in the two cultivars at pre-flowering stage. Results showed that PFD stress significantly increased the levels of soluble protein, free proline and free amino acid, and increased Al-pyrroline-5-car- boxylate synthetase （P-5-CS, EC 2.7.2.11） activity in the leaves of drought-tolerant and drought-sensitive cultivars. The activity of proline dehydrogenase （proDH） （EC 1.5.99.8） decreased under PFD stress in both cultivars. The leaves of the tolerant cultivar maintained higher increments of osmolyte levels, lower increments of MDA content and ion leakage, as well as a higher increased proportion of P-5-CS activity and higher inhibited proportion of proDH activity under water stress compared with the drought-sensitive cultivar. The study suggests that proline accumulation in peanut leaves under PFD can be explained by the higher enhanced activities of P-5-CS and higher inhibition of proDH. The results will provide useful information for genetic improvement of peanut under drought tolerance.

Identification of main effect and epistatic QTLs controlling initial flowering date in cultivated peanut(Arachis hypogaea L.)

Initial flowering date(IFD)is closely related to mature period of peanut pods.In present study,a population of recombinant inbred lines(RIL)derived from the cross between Silihong(female parent)and Jinonghei 3(male parent)was used to map QTLs associated with IFD.The RIL population and its two parental cultivars were planted in two locations of Hebei Province,China from 2015 to 2018(eight environments).Based on a high-density genetic linkage map(including 2996 SNP and 330 SSR markers)previously constructed in our laboratory,QTLs were analyzed using phenotypic data and the best linear unbiased prediction(BLUP)value of initial flowering date by inclusive composite interval mapping(ICIM)method.Interaction effects between every two QTLs and between individual QTL and environment were also analyzed.In cultivated peanut,IFD was affected by genotypic factor and environments simultaneously,and its broad sense heritability(h2)was estimated as 86.8%。Using the IFD phenotypic data from the eight environments,a total of 19 QTLs for IFD were detected,and the phenotypic variation explained(PVE)by each QTL ranged from 1.15 to 21.82%.Especially,five of them were also detected by the BLUP value of IFD.In addition,12 additive QTLs and 35 pairs of epistatic QTLs(62 loci involved)were identifed by the joint analysis of IFD across eight environments.Three QTLs(qIFDB04.1,qIFDB07.1 and qIFDB08.1)located on chromosome B04,B07 and B08 were identified as main-effect QTL for IFD,which had the most potential to be used in peanut breeding.This study would be helpful for the early-maturity and adaptability breeding in cultivated peanut.

Cloning, Expression Pattern Analysis and Subcellular Localization of Resveratrol Synthase Gene in Peanut (<i>Arachis hypogaea</i>L.)

Resveratrol synthase (RS) is a key enzyme that plays a critical role in the resveratrol synthesis pathway. In this study, six RS genes were isolated and characterized from peanut variety “Zhenzhu Hong” by silico cloning and RT-PCR. Bioinformatics analysis showed that deduced amino acid sequences of the six cloned RS genes were highly conserved with a similarity from 95% to 99% when compared to the RS genes which had been deposited at the GenBank. The results of amino acid sequences analysis showed six RS proteins contained the Chal_Sti_Synt_N and ACP_Syn_III_C domains and can be classified to same family but with different evolutionary distance. Expression pattern analysis by QRT-PCR provided evidence indicating that the mRNA of six RS genes were primarily expressed in the peanut shell at different developmental stages with different expression levels, but only lower levels of them were evident in the peanut kernel. The subcellular localization of RS protein in onion epidermal cell was performed by Agrobacterium tumefaciens-mediated transformation and the green fluorescent was monitored by confocal fluorescence microscopy. The results indicated that, RS1 and RS5 were located in the nucleus and plasma membrane respectively, while the RS2, RS3, RS4 and RS6 were located in both nucleus inner membrane and plasma membrane. The data will provide basic information for elucidating the regulatory mechanisms and enzyme kinetics underlying the RS genes in the resveratrol synthase pathway.

Gomparative analysis of DGAT3（diacylglycerol acyltraiisferase 3） gene from different peanut （Arachis hypogaea L.） varieties

Cultivated peanut is one of the primary sources of vegetable oil and protein in developing countries. DG〉A73 family in peanut cotyledons has no membrane-bound regions suggesting that cytosol is one of the sites for triacylglycerol （TAG） biosynthesis in oilseeds. According to functional annotation and classification of 5 cDNA libraries, 12 unigenes were found with relation of peanut DGAT3 in different organs. Three clones of unigenes, OCP- contig168t OCPcontig12101-3 and OCPcontigl2388-1 were selected for sequencing. Full length sequence of DGAT3 was obtained, showing over 98% sequence similarity with peanut DGAT3 gene AY875644 or EU183333. Upon cluster analysis, DGAT3 of 40 culti- vars were divided into 3 types, namely AhDGATS-1, AhDGAT3-2 and AhDGAT3-3. Coding regions are 1023, 1038 and 1026 base pairs which encoded proteins with 340-, 345- and 341-amino acids, respectively. DGAT3-3 might be a novel gene type among the DGAT3 family which provides great help for studying DGAT3 gene evolution in peanut.

Advances in Photosynthetic Characteristics of Peanut

Peanut is an important oil crop and economic crop in China. In this pa- per, the status and advances of the factors affecting peanut photosynthesis, such as light intensity, temperature, carbon dioxide concentration, water deficit and fertility situation, the relationship between peanut photosynthetic rate and different cultivation system, and the relationship between peanut photosynthetic rate and varieties yield potential, were deeply reviewed, expecting to provide references for peanut variety breeding with high photosynthetic efficiency and high yield potential.

不同土壤类型对花生(Arachis hypogaea L.)籽实镉积累特性的影响

为了在不同土壤环境下选育出低镉(Cd)积累型花生品种以提高花生品质,以‘白沙1016号’品种花生(Arachis hypogaea L.)为供试作物,棕壤和潮土为供试土壤,采用盆栽试验的方法,研究了2种类型土壤对花生籽实Cd积累特性的影响。结果表明:2种类型土壤条件下的花生籽实生物量差异显著(P<0.05);在供试土壤Cd处理范围内(≤10.0 mg/kg),籽实生物量均随2种土壤Cd处理浓度增加呈"低促高抑"现象。花生籽实对土壤Cd的生物富集系数均随2种土壤Cd处理增加呈显著降低趋势(P<0.05),且土壤类型间差异不显著。花生籽实Cd含量和Cd生物富集量均随2种土壤Cd处理的增加而显著增加(P<0.05),但两者在棕壤介质中均显著大于潮土(P<0.05)。土壤类型对花生籽实Cd积累差异的影响主要体现在籽实Cd含量和生物富集量方面。而土壤pH、氧化还原电位(Eh)等均是影响籽实对Cd积累差异的重要因素。

Antioxidant activity,total phenolic,and resveratrol content in five cultivars of peanut sprouts

Objective: To investigate the change in total phenolic compounds, antioxidant activity,and resveratrol content of five different germinated peanut cultivars.Methods: The germinated sprouts of five peanut cultivars(Kalasin1, Kalasin2, Konkaen,Konkaen4, and Tainan9) were extracted with 80% ethanol and collected as crude extract.The antioxidant capacities were determined with 2,2-diphenyl-1-picrylhydrazyl and ferric ion reducing antioxidant power method.The total phenolic compound was measured using the Folin–Ciocalteau assay.The qualification and quantification of resveratrol was performed by high performance liquid chromatography method.Results: Among the five cultivars, a three-day germination of Kalasin1 showed the highest phenolic content [(40.67 ± 2.62) mg gallic acid/g dry weight], expressed the highest 2,2-diphenyl-1-picrylhydrazyl antioxidant value [(80.51 ± 1.47) mmol/L Trolox/g dry weight], and ferric ion reducing antioxidant power antioxidant value [(171.33 ± 8.59)mmol/L ascorbic acid/g dry weight].However, the high performance liquid chromatography result of Kalasin2 significantly increased to the highest resveratrol content of(6.44 ± 1.26) mg/g dry weight on the second day of germination.Conclusions: The variation of phytochemical content in the peanut sprout is due to the effect of the peanut cultivar and the germination period.

Phenolic compounds from Peanut testa

Phytochemical investigation of peanut testa(the seed coat of Arachis hypogaea L.)led to the isolation of eight phenolic compounds,including caffeic acid(1),methyl caffeate(2),ethyl caffeate(3),methyl protocatechuate(4),ethyl protocatechuate(5),butyl protocatechuate(6),(E)-p-hydroxycinnamic acid methyl ester(7),and resveratrol(8).The structures of the compounds were elucidated through spectroscopic data analysis and comparison with the previously reported literature.Among them,compounds 2,3,5,and 6 were obtained from Arachis hypogaea L.for the first time.

Interaction of Seedling Germination, Planting Date, and Flumioxazin on Peanut Physiology under Irrigated Conditions

Diclosulam and flumioxazin applied preemergent (PRE) results in direct peanut exposure to these herbicides prior to seedling emergence. Flumioxazin has been reported to induce injury in adverse weather (i.e. cool-wet soil conditions) at crop emergence. Research at Ty Ty and Plains, Georgia evaluated the physiological effects of PRE herbicides to emerging peanut in 2018 and 2019. Peanut seed with variable germination and different planting dates were evaluated as additional factors. Peanut plant physiological measurements included electron transport (ETR), net assimilation rate (Anet), quantum yield of PSII (ΦPSII), and stomatal conductance to water vapor (GSW). Data were obtained from V3 to R1 peanut growth stages using a LiCOR 6800, along with stand counts and plant width measures. In 2018, diclosulam reduced peanut ETR when measured across multiple growing degree days (GDD) after planting, compared to the nontreated control (NTC). Flumioxazin reduced peanut ETR compared to the NTC, at several sample timings for each planting date. In 2018 and 2019 at both locations, flumioxazin impacted Anet less than ETR, but was consistently similar to/or greater than the NTC. Peanut ΦPSII responded similarly as Anet at each location and yr. GSW was variable in both years;however flumioxazin treated plants had higher GSW rates than other treated plants. Peanut stand counts, plant widths, and pod yields noted few differences compared to the physiological measures. Though some peanut plant physiological differences were noted when measured at varying GDD’s after planting with the different PRE treatments, planting date, and seed vigor, no specific trends were observed. Growers will often observe peanut injury from flumioxazin early in the season. However, it is transient and does not affect yield.

Molecular characterization of a peanut variety and its derivatives based on SSR and COP analysis

Despite the economic importance of the peanut, no studies have been carried out to deter-mine the correlation between genetic distances based on molecular markers and on coefficient of parentage （COP） data. In this study, simple sequence repeat （SSR） and pedigree data were used to assess the ge-netic distance between the Fuhuasheng variety and its derivative cultivars. A total of 39 SSR polymor-phism primers were used, and 151 bands were obtained, with an average of 2. 04 bands in each primer. The genetic SSR - based distance （GD） values ranged from 0. 02 to 0. 81, while the COP - based GD ranged from 0. 25 to 0. 98. Certain Fuhuasheng loci displayed higher transmission rates. These loci or nearby chromosomal regions might be associated with desirable traits in Fuhuasheng variety, thus being frequently selected in breeding programs. Therefore, it can be suggested that COP analysis should be the preferred method for estimating genetic diversity invarieties with available complete pedigree information and parents. In this case, marker analysis would provide the best estimations.

花生含油量全基因组选择及近红外光谱筛选的育种技术探究

花生含油量对单位面积产油量至关重要。该性状受多个微效基因控制,但可用的紧密连锁标记十分有限,传统的分子标记辅助选择育种准确性不高。全基因组选择作为一种新的育种方法,可实现对数量性状的早期预测;近红外光谱分析可对作物品质性状(如含油量等)进行无损检测。通过两者优势互补,建立花生含油量全基因组选择和近红外光谱筛选联合的育种技术,探讨影响花生含油量全基因组选择预测准确性的因素,为花生分子育种奠定理论基础。本研究以216个重组自交系为材料构建训练群体;分别以139、464和505株F_(2)、F_(3)和F_(4)为材料构建育种群体;利用自主开发的“PeanutGBTS40K”液相芯片进行基因分型,开展含油量全基因组选择育种模型分析;通过联合全基因组选择和近红外光谱筛选技术,开展花生含油量性状的育种应用,并评价其育种效果。结果显示,对训练群体进行基因分型后,总共获得30,355个高质量SNPs,并用于11个全基因组预测的模型选择分析。含油量预测准确性最高的模型为rrBLUP,其次是randomforest和svmrbf。以重组自交系为预测群体,F_(2)、F_(3)和F_(4)各世代含油量的预测准确性分别为0.116、0.128和0.119;以重组自交系叠加上一轮的育种群体为预测群体,各世代含油量的预测准确性分别为0.116、0.131和0.160。全基因组选择联合近红外筛选要比单独的全基因组选择对各世代的含油量选择效果提高1.8%、2.7%和3.4%;与单独的近红外筛选相比,差异不显著(0.10%、0.06%和0.07%);而近红外筛选与全基因组选择相比,含油量可显著提高1.7%、2.6%和3.3%。通过联合全基因组选择和近红外光谱筛选育种,F_(3)和F_(4)分别比F_(2)的含油量提高1.2%和1.0%。F_(4)总共获得16个入选改良株系,有10个株系含油量≥55.0%,其中2个株系(SF_(4)_201和SF_(4)_379)的理论产量分别比对照增产7.0%和11.1%。本研究通过建立花生含油量性状的全基因组选择-近红外光谱筛选联合育种技术,可有效实现花生含油量性状的遗传改良。

盐胁迫下氮素对花生种子萌发和种子际细菌菌群结构的调控

【目的】盐胁迫影响花生种子萌发和植株生长,阐明盐胁迫下适量施肥提高种子萌发率和花生产量的内在调控机制,并解析该过程与种子际土壤细菌菌群结构的关系,为通过改良种子际土壤微生物环境,提高花生出苗健苗率、耐盐抗逆性和花生生产能力提供理论和技术依据。【方法】以耐盐花生品种(花育25号,HY25)为试验材料,设置3个氮素水平0、90和180 kg/hm^(2),采用盆栽试验和高通量测序技术,阐明氮肥施用对盐胁迫下花生种子际微生物菌群结构、花生发芽出苗和产量的影响。【结果】施加氮肥可有效提高花生种子在盐胁迫下的发芽率和最终产量,并以施氮量90 kg/hm^(2)最适。16S rRNA测序分析显示,种子际的土壤细菌以变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)、酸杆菌门(Acidobacteria)、拟杆菌门(Bacteroidetes)、绿弯菌门(Chloroflexi)及芽孢杆菌门(Gemmatimonadetes)等为优势菌门。在属水平上,盐胁迫虽然提高了有益菌属拟杆菌属(Bacteroides)的相对丰度,但同时导致有害的链球菌属(Streptococcus)增多,最终降低了有益菌属芽孢杆菌属(Bacillus)、鞘脂单胞菌属(Sphingomonas)和溶杆菌属(Lysobacter)的相对丰度。盐胁迫下施氮可以显著改善种子际的土壤微环境,提高有益菌属拟杆菌属、芽孢杆菌属、鞘脂单胞菌属的相对丰度,对土壤修复和地力提升有一定的帮助,同时还能增强花生抗逆性。【结论】盐胁迫下适量施氮可提高种子际有益菌属的相对丰度,从而提高花生种子的发芽率和耐盐性,最终促进盐胁迫下的花生增产。

ARC-BBBE在长江流域花生产区试验示范效果

我国长江流域花生生产易遭受黄曲霉菌侵染及黄曲霉毒素污染。在团队前期研制了微生物菌剂ARCBBBE,2022年在长江流域花生产区(湖北、湖南、江西、四川)四省开展ARC-BBBE花生生产示范技术应用,研究结果显示:在长江流域花生产区,施用ARC-BBBE对土壤中黄曲霉菌丰度的抑制率范围为36.87%~94.70%,平均抑制率为63.02%;同时,ARC-BBBE可增强花生的固氮酶活性,增加花生根瘤的数量以及重量,增加花生植株的生物量,花生增产率范围为7.23%~53.85%,平均增产率为20.58%。综合示范结果表明:花生施用ARC-BBBE可作为一项增加花生单产、提升花生产能、保障花生产业健康发展的栽培技术。

花生分子标记辅助育种研究进展与展望

花生是重要的食用植物油和植物蛋白来源,高产优质抗病是花生新品种选育的主要目标。目前生产上大面积推广的优良品种主要以传统杂交育种技术选育而成,育种周期长、效率低、成本高。分子标记辅助选择可显著提高育种的精准性和效率。高密度的基因型数据是花生产量、品质、抗病性状QTL定位和开发分子标记的基础。2019年我国花生骨干亲本狮头企和伏花生以及美国匍匐型花生品种Tifrunner的基因组序列相继公布,极大推动了花生重要农艺性状的分子标记开发和应用。近年来,花生籽仁油酸含量、脂肪含量等品质性状,根结线虫病、锈病、叶斑病、青枯病等抗病性状,以及荚果、籽仁大小等产量组成性状的分子标记相继被开发。利用分子标记辅助育种,成功选育出了高油酸且高含油量、高油酸且抗病花生新品种或新种质。未来花生分子标记的开发利用需要重视优异野生种质资源的表型精准鉴定,建立高通量表型及基因型检测平台,以及全基因组选择技术策略的应用。

不同播种方式下高油酸花生生长性状及产量的表现

以高油酸花生(Arachis hypogaea L.)品种中花215、中花28和中花34为试验材料,采用小区试验对比的方法研究不同播种方式(单粒播种、双粒播种、单双粒间播)对高油酸花生生长性状及产量的影响。结果表明,不同播种方式对高油酸花生生长性状及产量均产生一定影响,单粒播种更有利于花生单株生长发育,相比其他两种播种方式,能显著提高叶片SPAD值、单株结果数、单株生产力和干果产量;单双粒间播和双粒播种的干果产量无显著差异;3个高油酸品种单粒播种的经济效益最高,单双粒间播次之,双粒播种最低;相同播种方式下,中花215的产量和经济效益最高,中花34次之,中花28最低。

花生ASR基因家族特性及其对干旱和盐胁迫的响应

【目的】探究花生ASR基因家族特性及其在干旱和盐胁迫响应中的作用,为培育花生抗旱抗盐新品种提供潜在基因位点。【方法】通过生物信息学方法在全基因组水平鉴定花生ASR家族并分析其基本特性,借助转录组数据分析其在200 mmol/L NaCl及模拟干旱PEG处理后的表达变化。【结果】(1)鉴定到7个花生ASR基因,pI为5.34~6.98,蛋白脂肪系数为23.77~56.84,GRAVY值均为负值,表明这7个蛋白均是亲水性蛋白;(2)AhASR3与AhASR7基因表达模式相似,转录水平较高,基因结构及蛋白结构域和保守基序的位置和数量较相似,motif 5、6、9仅存在于AhASR3与AhASR7蛋白中;(3)AhASR1、AhASR5及AhASR2的启动子区域有干旱诱导MYB转录因子的结合位点,发现AhASR1、AhASR2及AhASR4的启动子区有ABA响应元件;(4)AhASR2、AhASR3及AhASR7在200 mmol/L NaCl处理后根部出现较明显转录上调;(5)AhASR1、AhASR3、AhASR4及AhASR7分别在PEG处理4 h和8 h后,转录水平出现2倍以上上调。【结论】花生ASR家族蛋白均为亲水性蛋白,各成员之间既有保守结构域也有特异性序列,大部分成员启动子区都具有干旱响应相关元件,并受到盐处理以及模拟干旱处理的诱导表达,可作为耐盐耐旱花生品种培育的重要候选基因。

花生黄曲霉侵染抗性的AFLP标记

本研究利用抗、感黄曲霉侵染的花生品种为亲本配制杂交组合“中花5号×J11”,以其F2分离群体为研究材料,采用AFLP技术和BSA分析方法,获得了与花生黄曲霉菌侵染抗性连锁的2个分子标记,标记与抗性间的遗传距离分别为8.8 cM和6.6 cM;利用获得的分子标记对抗、感黄曲霉的花生种质资源进行了分子鉴定,试验结果表明,分子标记与抗性鉴定结果具有较高的一致性,证实了两标记应用于研究群体之外的育种潜力。该抗侵染分子标记的建立为开展花生抗黄曲霉侵染辅助选择育种提供了有效的筛选技术。

不同抗旱性花生品种的根系形态发育及其对干旱胁迫的响应

为明确不同抗旱性花生品种的根系形态发育特征,探讨其根系形态发育特征对不同土壤水分状况的响应机制,在防雨棚旱池内进行土柱栽培试验,研究抗旱型品种"花育22号"、"唐科8号"和干旱敏感型品种"花育23号"3个不同抗旱性花生品种根系形态发育特征及其对干旱胁迫的响应。结果表明:抗旱型品种根系较发达,具有较大的根系生物量、总根长、总根系表面积。干旱胁迫使抗旱型品种根系总表面积和体积增加,而干旱敏感型品种则相反。干旱胁迫显著增加抗旱型品种"花育22号"20 cm以下土层内根长密度分布比例及根系表面积和体积,但"唐科8号"相应根系性状仅在20—40 cm土层内增加;干旱胁迫使干旱敏感型品种"花育23号"40 cm以下土层内各根系性状升高,但未达显著水平且其深层土壤内各根系性状增加幅度小于"花育22号"。花生根系总长、总表面积及0—20 cm土层内根系性状与产量间呈显著或极显著正相关。土壤水分亏缺条件下,花生主要通过增加深层土壤内根长、根系表面积和体积等形态特性,优化空间分布构型,以调节植株对水分的利用。