Detection of Allelic Variation in Chinese Wheat (Triticum aestivum L.) Germplasm with Drought ToleranceUsing SSR Markers

Allelic variation in two domestic wheat landraces, Pingyaobaimai and Mazhamai, two cornerstone breeding materials and their derived cultivars with drought tolerance was detected by SSR (simple sequence repeat) markers. The clustering of 25 accessions showed that the similarity between Pingyaobaimai and Yandal817, the latter was developed from the former, was 0.71, the highest one of all accessions, but the similarities were very low between these two accessions and other accessions including their derived cultivars. A similar situation was revealed between Mazhamai and its derived cultivars. Pingyaobaimai and its three derived cultivars shared three alleles at loci Xgwm526, Xgwm538 and Xgwm126 on chromosome arms 2BL, 4BL and 5AL, respectively. There were six shared alleles in Mazhamai and its derived cultivars, in order of Xgwm157, Xgwm126, Xgwm212, Xgwm626, Xgwm471 and Xgwm44 on chromosome arms 2DL, 5AL, 5DL, 6BL, 7AS and 7DC, respectively. Only one shared allele was detected between the pedigrees of Pingyaobaimai and Mazhamai. The difference of shared alleles in two cornerstone breeding materials and their derived cultivars revealed the diversity in Chinese wheat germplasm with drought tolerance and the complication in genetic basis of drought tolerance in wheat.

Analysis of drought tolerance and genetic and epigenetic variations in a somatic hybrid between Ipomoea batatas (L.) Lam. and I. triloba L.

The somatic hybrid KT1 was previously obtained from protoplast fusion between sweetpotato （Ipomoea batatas （L.） Lam.） cv. Kokei No. 14 and its wild relative I. triloba L. However, its genetic and epigenetic variations have not been investigated. This study showed that KT1 exhibited significantly higher drought tolerance compared to the cultivated parent Kokei No. 14. The content of proline and activities of superoxide dismutase （SOD） and photosynthesis were significantly increased, while malonaldehyde （MDA） content was significantly decreased compared to Kokei No. 14 under drought stress. KT1 also showed higher expression level of well-known drought stress-responsive genes compared to Kokei No. 14 under drought stress. Amplified fragment length polymorphism （AFLP） and methylation-sensitive amplified polymorphism （MSAP） analyses indicated that KT1 had AFLP and MSAP band patterns consisting of both parent specific bands and changed bands. Fur- ther analysis demonstrated that in KT1. the proportions of Kokei No. 14 specific genome components and methylation sites were much greater than those of I. triloba. KT1 had the same chloroplast and mitochondrial genomes as Kokei No. 14. These results will aid in developing the useful genes ofI. triloba and understanding the evolution and phylogeny of the cultivated sweetpotato.

Mapping of QTL Associated with Drought Tolerance in a Semi-Automobile Rain Shelter in Maize (Zea mays L.)

Drought is a major constraint in maize production worldwide. We studied quantitative trait loci （QTL） underlying drought tolerance for maize plants grown in two different environments. Traits investigated included ASI, plant height, grain yield, ear height, and ear setting. A genetic linkage map was constructed with 120 simple sequence repeat （SSR） markers based on an F2 population derived from a cross between D5 （resistant parent） and 7924 （susceptible parent）. Correlation and heritability were calculated. QTLs of these traits were identified by composite interval mapping combined with a linkage map covering 1 790.3 cM. The markers were arranged in ten linkage groups. QTL mapping was made of the mean trait performance of the 180 F2：3 population. The results showed five, five, six, four, and five QTLs for ASI, plant height, grain yield, ear height, and ear setting under full irrigation condition, respectively, and four, seven, six, four, and four QTLs for ASI, plant height, grain yield, ear height, and ear setting under severe late stress conditions, respectively. Especially the four QTLs detected for five traits in 2008 and 2009. The universal QTLs information generated in this study will aid in undertaking an integrated breeding strategy for further genetic studies in drought tolerance improvement in maize.

QTL mapping of drought tolerance traits in soybean with SLAF sequencing

Drought stress is an important factor affecting soybean yield.Improving drought tolerance of soybean varieties can increase yield and yield stability when the stress occurs.Identifying QTL related to drought tolerance using molecular marker-assisted selection is able to facilitate the development of drought-tolerant soybean varieties.In this study,we used a high-yielding and drought-sensitive cultivar‘Zhonghuang 35’and a drought-tolerant cultivar‘Jindou 21’to establish F6:9 recombinant inbred lines.We constructed a highdensity genetic map using specific locus amplified fragment sequencing(SLAF-Seq)technology.The genetic map contained 8078 SLAF markers distributing across 20 soybean chromosomes with a total genetic distance of 3780.98 c M and an average genetic distance of0.59 c M between adjacent markers.Two treatments(irrigation and drought)were used in the field tests,the Additive-Inclusive Composite Interval Mapping(ICIM-ADD)was used to call QTL,and plant height and seed weight per plant were used as the indicators of drought tolerance.We identified a total of 23 QTL related to drought tolerance.Among them,seven QTL(q PH2,q PH6,q PH7,q PH17,q PH19-1,q PH19-2,and q PH19-3)on chromosomes 2,6,7,17,and 19 were related to plant height,and five QTL(q SWPP2,q SWPP6,q SWPP13,q SWPP17,and q SWPP19)on chromosomes 2,6,13,17,and 19 were related to seed weight and could be considered as the major QTL.In addition,three common QTL(q PH6/q SWPP6,q PH17/q SWPP17,and q PH19-3/q SWPP19)for both plant height and seed weight per plant were located in the same genomic regions on the same chromosomes.Three(q PH2,q PH17,and q PH19-2)and four novel QTL(q SWPP2,q SWPP13,q SWPP17,and q SWPP19)were identified for plant height and seed weight per plant,respectively.Two pairs of QTL(q PH2/q SWPP2 and q PH17/q SWPP17)were also common for both plant height and seed weight per plant.These QTL and closely linked SLAF markers could be used to accelerate breeding for drought tolerant cultivars via MAS.

Haplotypic Structure and Allelic Variation of rab17,an ABA-Responsive Gene,in a Mini Core Set of Chinese Diversified Maize Inbred Lines

Drought stress is one of the most important factors limiting maize production. Rab17 is an ABA-responsive gene and associated with drought tolerance. In order to identify haplotypic structure and mine allelic variants at tab17 locus, nucleotide diversity and linkage disequilibrium （LD） structure of rab17 were evaluated among a mini core set of Chinese diversified maize inbred lines. Totally, 19 SNP and 18 insertion/deletions （InDels） were identified, among which 81% were in non-coding regions and 19% in coding regions. The results showed that a high level of diversity appeared within 1 kb upstream of the rabl 7 locus, and declined quickly downstream of the gene region. Rapid decay of linkage disequilibrium of rabl 7 region with distance within 1 kb was detected. Functional markers which can be developed based on haplotype 14 are expected to have contribution to molecular breeding for drought tolerance.

A reference-grade genome of the xerophyte Ammopiptanthus mongolicus sheds light on its evolution history in legumes and droughttolerance mechanisms

Plants that grow in extreme environments represent unique sources of stress-resistance genes and mechanisms.Ammopiptanthus mongolicus(Leguminosae)is a xerophytic evergreen broadleaf shrub native to semi-arid and desert regions;however,its drought-tolerance mechanisms remain poorly understood.Here,we report the assembly of a reference-grade genome for A.mongolicus,describe its evolutionary history within the legume family,and examine its drought-tolerance mechanisms.The assembled genome is 843.07 Mb in length,with 98.7%of the sequences successfully anchored to the nine chromosomes of A.mongolicus.The genome is predicted to contain 47611 protein-coding genes,and 70.71%of the genome is composed of repetitive sequences;these are dominated by transposable elements,particularly longterminal-repeat retrotransposons.Evolutionary analyses revealed two whole-genome duplication(WGD)events at 130 and 58 million years ago(mya)that are shared by the genus Ammopiptanthus and other legumes,but no species-specific WGDs were found within this genus.Ancestral genome reconstruction revealed that the A.mongolicus genome has undergone fewer rearrangements than other genomes in the legume family,confirming its status as a"relict plant".Transcriptomic analyses demonstrated that genes involved in cuticular wax biosynthesis and transport are highly expressed,both under normal conditions and in response to polyethylene glycol-induced dehydration.Significant induction of genes related to ethylene biosynthesis and signaling was also observed in leaves under dehydration stress,suggesting that enhanced ethylene response and formation of thick waxy cuticles are two major mechanisms of drought tolerance in A.mongolicus.Ectopic expression of AmERF2,an ethylene response factor unique to A.mongolicus,can markedly increase the drought tolerance of transgenic Arabidopsis thaliana plants,demonstrating the potential for application of A.mongolicus genes in crop improvement.

Identification of Functional Genetic Variations Underlying Drought Tolerance in Maize Using SNP Markers

Single nucleotide polymorphism （SNP） is a common form of genetic variation and popularly exists in maize genome. An Illumina GoldenGate assay with 1 536 SNP markers was used to genotype maize inbred lines and identified the functional genetic variations underlying drought tolerance by association analysis. Across 80 lines, 1 006 polymorphic SNPs （65.5% of the total） in the assay with good call quality were used to estimate the pattern of genetic diversity, population structure, and familial relatedness. The analysis showed the best number of fixed subgroups was six, which was consistent with their original sources and results using only simple sequence repeat markers. Pairwise linkage disequilibrium （LD） and association mapping with phenotypic traits investigated under water-stressed and well-watered regimes showed rapid LD decline within 100–500 kb along the physical distance of each chromosome, and that 29 SNPs were associated with at least two phenotypic traits in one or more environments, which were related to drought-tolerant or drought-responsive genes. These drought-tolerant SNPs could be converted into functional markers and then used for maize improvement by marker-assisted selection.

Natural Variation in the Sequence of SNAC1 and Its Expression Level Polymorphism in Rice Germplasms under Drought Stress

Water is a major limiting factor for food production and many countries fail to produce sufficient food for their population due to severe water scarcity （Jury and Vaux, 2005）. Rice is the main staple food worldwide. More than 50% of rice in the world is rain-fed and drought causes severe reduction in rice grain yield in rain-fed environments （Venuprasad et al., 2007; Zhang, 2007; Sandhu et al., 2014）. Therefore, enhancing drought resistance （DR） of rice is important for food security. However, DR is a complex trait, which is controlled by a large number of loci with small effect and is also affected by different genetic background, genotype-by-environment interaction and other stresses such as heat （Hu and Xiong, 2014）.

Two gene clusters and their positive regulator SlMYB13 that have undergone domestication-associated negative selection control phenolamide accumulation and drought tolerance in tomato

Among plant metabolites,phenolamides,which are conjugates of hydroxycinnamic acid derivatives and polyamines,play important roles in plant adaptation to abiotic and biotic stresses.However,the molecular mechanisms underlying phenolamide metabolism and regulation as well as the effects of domestication and breeding on phenolamide diversity in tomato remain largely unclear.In this study,we performed a metabolite-based genome-wide association study and identified two biosynthetic gene clusters(BGC7 and BGC11)containing 12 genes involved in phenolamide metabolism,including four biosynthesis genes(two 4CL genes,one C3H gene,and one CPA gene),seven decoration genes(five AT genes and two UGT genes),and one transport protein gene(DTX29).Using gene co-expression network analysis we further discovered that SlMYB13 positively regulates the expression of two gene clusters,thereby promoting phenolamide accumulation.Genetic and physiological analyses showed that BGC7,BGC11 and SlMYB13 enhance drought tolerance by enhancing scavenging of reactive oxygen species and increasing abscisic acid content in tomato.Natural variation analysis suggested that BGC7,BGC11 and SlMYB13 were negatively selected during tomato domestication and improvement,leading to reduced phenolamide content and drought tolerance of cultivated tomato.Collectively,our study discovers a key mechanism of phenolamide biosynthesis and regulation in tomato and reveals that crop domestication and improvement shapes metabolic diversity to affect plant environmental adaptation.

假俭草抗旱变异体的筛选及其生理鉴定

通过长期继代(24个月)假俭草胚性愈伤组织,诱发体细胞无性系变异的发生,从再生植株中筛选抗旱变异体,获得了5个变异体植株。生理检测结果表明,干旱处理后所有植株叶片的相对含水量下降,相对电导率和丙二醛(MDA)含量升高,但抗旱变异体植株的相对含水量显著高于对照植株,相对电导率和MDA含量显著低于对照植株,表明变异体植株受干旱伤害程度较轻,提高了抗旱性。干旱处理前变异体植株与其对照植株间脯氨酸含量、SOD活性和CAT活性差异不大,干旱处理后所有植株的脯氨酸、SOD活性和CAT活性均升高,但变异体植株的脯氨酸含量低于对照植株,SOD和CAT活性高于对照植株。结果表明,变异体植株的抗旱性与在干旱条件下维持更高的SOD和CAT活性有关。

玉米耐旱功能标记辅助选择初探

干旱是影响玉米生产的主要因素之一,培育耐旱品种可以有效地保持其在干旱环境下的产量稳定性。随着生物信息学数据库的不断完善及基因组学技术的发展,耐旱通用QTL(Quantitative trait locus)的发掘为分子育种提供了新的机遇和方法。本研究在已发掘的耐旱通用QTL基础上,选取相关的18个连锁标记进行开发并且验证在不同种质背景下24份玉米自交系的耐旱性。结果表明,共检测出42个多态性位点,平均多态性信息量为0.4245;通过GGT32(Graphical GenoTypes)图示基因型软件分析SSR位点,得出umc2217、umc2029、phi099、umc1213和phi022这5个连锁标记可用来初步鉴定玉米耐旱性;利用卡方检验,得出phi022和umc2217均达到显著水平,其与耐旱密切相关。因此,这几个连锁标记不仅可被用于相应群体的耐旱分子标记辅助选择,而且为以后的标记辅助选择及抗旱性基因克隆的研究打下基础。

不同水分条件下两个树种木质部栓塞对P素添加的响应

在两种水分供给(干旱胁迫和适宜水分,土壤含水量分别为田间持水量的30%～40%和70%～80%)下,研究了耐旱树种元宝枫(Acer truncatum)和中生树种女贞(Ligustrum lucidum)木质部栓塞(以导水率(Percentage loss of hydraulic conductivity,PLC)损失程度衡量)对P素添加的响应。结果发现,两个树种PLC的日变化均呈现出先上升后降低的规律,表明木质部栓塞的形成与恢复是植物体的一种平常事件;除适宜水分条件的女贞外,P素可以显著提高元宝枫和遭受干旱胁迫时女贞的PLC;两种水分条件下,干旱胁迫时元宝枫木质部栓塞明显高于适宜水分供给时。女贞的PLC在两种水分状况下无显著差异;树种间,干旱胁迫促进了元宝枫木质部的栓塞形成,明显高于同等水分条件下的女贞。该研究结果证实了"木质部限流耐旱假设"。

大豆根系形态及苗期耐旱根系性状的研究

选取黄淮海地区大田大豆样本40份,在苗期和鼓粒期挖根观察根形态,同时在苗期采用盆栽对其耐旱性进行鉴定并测定了品种间根系形态和生理指标。结果表明,大豆品种根系表观形态在生长的不同时期以及在同一时期不同环境条件下不完全一致。大豆根系的主根长、根总长、根体积、根干重等形态指标和根系活力、根系总吸收面积、根系活跃吸收面积在品种之间、不同水分处理下均存在广泛的遗传变异,且干旱反应两极端类型品种根系各性状对干旱胁迫的反应具有显著差异,表明通过对根系性状的选择可以获得改良大豆地上部性状的根系指标,从而为大豆育种提供新的途径和方法。

小麦粒重基因TaGW2-6A编码区等位变异与抗旱性的关系

[目的]小麦籽粒大小及其在水、旱两种生态环境下的稳定性直接影响小麦的产量,研究小麦粒重与抗旱性的关系对品种高产稳产具有重要意义。探究粒重相关基因不同等位变异的抗旱性,进而确定抗旱高产的优异等位变异基因型,为利用该基因型进行小麦抗旱高产品种分子标记辅助选择及性状的遗传改良提供理论依据。[方法]以小麦粒重基因Ta GW2-6A编码区不同等位变异的中国春和兰考大粒(977 bp多一个"T"碱基插入)为亲本构建的含有325个株系的RIL群体为研究材料,依据序列"T"碱基插入设计引物,利用高分辨率熔解曲线分析技术(high resolution melting curve,HRM)鉴定RIL群体中Ta GW2-6A编码区不同等位变异基因型,并对其PCR产物进行测序分析。在水、旱两种生态环境下,测定小麦开花期、灌浆中期和乳熟期的叶绿素荧光参数、茎秆可溶性糖含量、抗旱指数等与抗旱紧密相关的指标,考察粒长、粒宽、千粒重等粒重相关性状,并研究这些抗旱相关指标及粒重相关性状与小麦粒重基因Ta GW2-6A编码区不同等位变异基因型之间的相关性。[结果]高分辨率熔解曲线分析技术可以准确地将小麦RIL群体按Ta GW2-6A编码区不同等位变异分为兰考大粒基因型(TT)、中国春基因型(tt)以及杂合基因型(Tt),且PCR产物测序结果显示高分辨率熔解曲线的差异是由"T"碱基插入引起的。水、旱两种生态环境下,RIL群体中TT、Tt基因型材料与tt基因型材料相比,粒长、粒宽、千粒重等粒重相关性状以及叶绿素荧光参数、茎秆可溶性糖相关性状、抗旱指数等抗旱相关指标的差异普遍达到显著或极显著水平。旱胁迫下,小麦RIL群体不同基因型材料的粒长、粒宽、千粒重等粒重相关性状、叶绿素荧光参数除初始荧光Fo外均有所降低,而茎秆可溶性糖含量则有所增加。但TT、Tt基因型材料的粒长、粒宽、千粒重及叶绿素荧光参数的下降幅度普遍比tt基因型材料小,而茎秆可溶性糖的增加幅度比tt基因型材料大。旱胁迫下,tt基因型的茎秆可溶性糖积累效率(accumulation efficiency of stem soluble sugar content,AESSC)和转运效率(remobilization efficiency of stem soluble sugar content,RESSC)有所降低,而TT、Tt基因型的茎秆可溶性糖积累效率和转运效率则有所提高。[结论]小麦粒重基因Ta GW2-6A编码区"T"碱基插入等位变异是大粒的优异等位变异,与此同时,该等位变异也是抗旱的优异等位变异,且抗旱能力与晋麦47相近。

玉米SNAC基因的遗传变异及耐旱性调控

以我国玉米育种中常用的16份自交系为材料,通过对SNAC(Stress-responsive NAM,ATAF1/2,CUC2)基因编码区及上游启动子区800 bp核苷酸序列进行测序,检测SNAC基因在不同杂种优势类群材料中的遗传变异。在12个SNAC基因中,其中有4个基因在上游800 bp区检测到遗传变异,有4个基因变异位点超过30个,多态性较高。虽然大多数SNAC基因变异以SNP(Single nucleotide polymorphism)为主,但在ZmNAC031467基因中检测到较多的插入缺失变异(In Del),达到基因总遗传变异的63.3%。通过PLACE软件对上游启动子有变异的4个基因进行3种耐逆结合元件的预测,结果显示4个基因均含有3种耐逆结合元件,但是基因突变对启动子结合元件的影响较小。再对检测到的遗传变异进行核苷酸多态性分析和中性检验,有7个SNAC基因核苷酸多态性较高,其中Zm NAC080308基因的多态性达到0.00962,推测这些基因在遗传漂移过程中受自然选择影响较大。利用t检验初步发现Zm NAC070395和Zm NAC080398基因的2个变异位点与耐旱相关性状关联,为进一步分析SNAC基因核苷酸变异与耐旱性状的关系提供一定的借鉴。

谷子耐旱性鉴定初探

在农用塑料薄膜搭制的旱棚内,严格控制供水量,依耐早系数为依据,对陕西省110份来自不同生态区的谷子品种资源的耐旱性进行鉴定,从中筛选出25个耐旱材料,列出了谷子在水分胁迫下其生态性状的耐旱性变差序列:千粒重>主茎节数>穗粗>株高>穗茎长>穗长>主茎直径>单株杆重>单株穗重>单株粒重。

耐旱与旱情敏感甘蔗品种根际土壤细菌群落组成及功能比较

【目的】比较耐旱性不同甘蔗品种根际土壤的细菌群落结构及功能,为筛选和开发利用有益功能细菌及构建新型甘蔗耐旱评价体系提供理论依据。【方法】选用耐旱甘蔗品种桂辐98-296和旱情敏感甘蔗品种桂糖36号,在设施内进行桶栽管理,以不种植甘蔗的盆土为空白对照(CK);采集其根际土壤及CK土壤样品,基于MiSeq高通量测序技术分析各土壤样品的细菌群落结构。【结果】桂辐98-296根际土壤的优势细菌数量在门、纲、目、科、属、种和可操作分类单元(OTU)7个分类水平上均高于CK;桂糖36号根际土壤优势细菌数量仅在目、属、种和OTU 4个分类水平上高于CK;在门分类水平,变形菌门(Proteobacteria)、放线菌门(Actinobacteriota)、酸杆菌门(Acidobacteriota)、厚壁菌门(Firmicutes)、绿弯菌门(Chloroflexi)、拟杆菌门(Bacteroidota)、芽单胞菌门(Gemmatimonadetes)和硝化螺旋菌门(Nitrospirae)细菌均是2个甘蔗品种根际土壤及CK土壤共有的优势细菌门类;桂辐98-296根际土壤还富集了绿弯菌门、放线菌门和芽单胞菌门等具有提升植物耐旱能力的细菌门类,其丰度占比均高于桂糖36号相应的细菌门类;在属分类水平,马杜拉菌属(Actinomadura)、norank_c_Actinobacteria、unclassified_o_Frankiales和norank_o_JG30-KF-CM45是2个甘蔗品种根际土壤的优势菌属;与桂糖36号相比,norank_f_Nitrosomonadaceae和norank_c_Actinobacteria是桂辐98-296根际土壤特有的优势细菌属。【结论】与旱情敏感甘蔗品种桂糖36号相比,耐旱甘蔗品种桂辐98-296根际土壤中富集了丰度高占比、且具有提高植物抗逆功能的绿弯菌门、放线菌门和芽单胞菌门等优势细菌门类;同时还富集了未分类的放线菌属和金霉素链霉菌属等特有优势细菌属,并拥有更丰富的信号分子与相互作用功能。桂辐98-296根际土壤中富集的特有优势细菌属norank_f_Nitrosomonadaceae和norank_c_Actinobacteria有望作为提高甘蔗耐旱能力的备选功能菌属开发利用。

Precipitation and seasonality affect grazing impacts on herbage nutritive values in alpine meadows on the Qinghai-Tibet Plateau

Aims Grasslands used for animal husbandry are chosen depending on the nutritive values of dominant herbage species.However,the influence of grazing in combination with precipitation and growing season on the nutritive values of dominant species has not been explicated.Methods To unveil the influence of the different grazing intensities on the nutritional values,an ecological study was formulated,namely fencing(G0),light grazing(G1),moderate grazing(G2)and high grazing(G3).This ambitious study was undertaken on the nutritive values of the four dominant species of herbage in an alpine meadow on the Qinghai-Tibet Plateau(QTP)during growing season(June–September)for two successive years,namely 2015(rainy year)and 2016(droughty year).Important Findings We found that(i)the nutritive value of Kobresia capillifolia,Polygonum viviparum and Caragana sinica was noticeably increased by grazing,but negligible effect on Potentilla fruticosa nutritive value was recorded.(ii)During the rainy year(2015),compared with G0,Polygonum viviparum and Potentilla fruticosa displayed 5.4 and 1.5%increases in the crude protein(CP)content and 8.5 and 2.4%increases in vitro true digestibility(IVTD),respectively,while the neutral detergent fibre(NDF)decreased by 13.5 and 0.9%,respectively.During the droughty year(2016),compared with G0,C.sinica and Potentilla fruticosa showed increases in the CP content by 4.3 and 1.3%and increases in the IVTD by 10.7 and 0.4%,respectively,during G3,while the NDF decreased by 6.0 and 1.0%,respectively.(iii)The nutritive values of all species were higher in the years when the rains were good.However,the nutritive values suffered heavily during drought conditions.Besides,the highest and lowest values of nutrition were detected in June and in September,respectively.The inter-seasonal and the inter-annual changes in the nutritional values of species were higher for K.capillifolia and Polygonum viviparum than for Potentilla fruticosa and C.sinica,suggesting that Potentilla fruticosa and C.sinica had higher water-use efficiency.(iv)Grazing clearly reduced the drought tolerance of three species and showed no effects on Potentilla fruticosa.(v)Grazing clearly increased the inter-month variation in the nutritional value of K.capillifolia and Polygonum viviparum but showed no effects on Potentilla fruticosa or C.sinica.Evidently,the grazing effects impacting the nutritional value of the dominant species of herbage exhibited conspicuous inter-annual and seasonal variations with species-specific influences and responses.Our findings are expected to have far-reaching implications enabling the authorities to arrive at strategic decisions and designing of relevant policies for the efficient management of the ecosystems ensuring the speed restoration of the QTP under severe grazing and extreme climatic circumstances.