Independent and combined drought and heat stress negatively affect wheat yield and physiology. The present study was aimed to quantify effects of Drought [D], heat [H] and combined heat and drought [HD] during reproductive stage on wheat yield and to identify physio-biochemical traits which were strongly associated with improved yield and tolerance of wheat under stressful conditions. One hundred and eight elite diverse wheat genotypes were exposed to [H], [D] and [HD] treatments from heading till maturity. Grain yield was reduced by 56.47%, 53.05% and 44.66% under [HD], [H] and [D] treatment, respectively. The [HD] treatment affects the grain yield by reducing metabolism and mobilization of reserves to developing grains and leaves. Disintegration of membrane structure, chlorophyll and protein molecules was higher under [H] stress than [D] stress while water status of genotypes and sink strength was more affected by [D] than [H] stress. Multivariate analysis showed a strong correlation of chlorophyll content before and after anthesis, water-soluble carbohydrates (WSC), proline content (PC) and all other studies agronomic and physiological traits with grain yield while days to anthesis (DTA) and days to maturity (DTM) were negatively associated with grain yield under stress showing advantage of early maturity during stress. Traits having a major contribution in the first two principal components under different stress treatments may lead to improved varieties with heat and drought stress tolerance. To best of over knowledge, the present study is the first detailed study which used physiological and biochemical traits to explain the variation in grain yield and related traits in diverse wheat germplasm.

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Most investigations to date aiming to identify the genetic basis of the stress response of wheat (Triticum aestivum L.) have focused on the response to single stress agents such as high temperature or drought, even though in the natural situation, these stresses tend often to occur together. Here, a panel of 108 spring type bread wheat cultivars was phenotyped for 15 yield and yield related traits for two years (2014/15 and 2015/16) under non-stressed conditions, under high temperature stress, under drought and under a combined high temperature and drought regime. The mean loss in grain yield caused by all stress regimes was 51.33%. Analysis of variance (ANOVA) of yield trait showed significant differences among genotypes environments and their interactions (G×E). All the studied traits had higher heritability values which ranged from 0.35–0.94 under [C], 0.58–0.95 under [D], 0.62–0.93 under [H] and 0.60–0.95 under [HD]. GWAS was performed by using 9,646 informative SNP markers and based on these polymorphic SNPs population structure analysis divided whole germplasm into five major sub-populations. Mixed model association analysis detected 503 marker-trait associations (MTAs) at P ≤0.001 while 329 MTAs crossed FDR ≤ 0.05 for all traits with phenotypic variances (R2) ranged from 24.83% to 12.51%. Seven new pleiotropic SNPs on chromosome 7D and IAAV8258 (86.91cM) and wsnp_Ex_c7168_12311649 (57.93cM) on chromosome 5A were most stable association in present study. Furthermore, candidate genes Psy and Sr25 (TG0040) were also significant in present study, these genes were previously mapped on 7A and 7D. The region on 7D was assiociated with 7DL.7Ag translocation from Lophopyrum carring rust resistance Yr16 and many other genes. Similarly region on chromosome 7A which was associated with Psy gene was linked with grain yellow pigment content QTLs. Favourable alleles controlling grain yield were of vital importance and incorporation of these alleles after validation through marker assisted selection and fine mapping could be helpful in wheat yield improvement stress and non-stress conditions.

There are 300 known Saussurea species. Among them, Saussurea lappa (S. lappa) is a representative perennial herb, globally distributed across Himalaya region. S. lappa has been traditionally used in medicines without obvious adverse effects. Despite significant progress in phytochemical and biological analyses of S. lappa over the past few years, inclusive and critical reviews of this plant are anachronistic or quite limited in scope. The present review aims to summarize up-to-date information on the active constituents, pharmacology, traditional uses, trade and challenges in conservation and sustainable use of S. lappa from the literature. In addition to botanical studies and records of the traditional use of S. lappa in over 43 diseases, scientific studies investigating the latent medicinal uses of this species and its constituent phytochemicals for a range of disorders are presented and discussed. The structure, bioactivity, and likely mechanisms of action of S. lappa and its phytochemicals are highlighted. Although some progress has been made, further scrupulous efforts are required to investigate the individual compounds isolated from S. lappa to validate and understand its traditional uses and develop clinical applications. The present review offers preliminary information and gives direction for further basic and clinical research into this plant.

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