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Key message: SSR-based characterization revealed a high genetic diversity, negligible genetic differentiation, insignificant inbreeding, and subtle genetic structure in Myrica esculenta populations of Western Himalayas, indicating a high adaptive and evolutionary potential. Myrica esculenta is a high-valued wild edible fruit-bearing tree of sub-Himalayan region experiencing noticeable deterioration in its stand structure. This study aimed to unveil the gene diversity and spatial genetic structure of M. esculenta populations in the Western Himalayas under the state of Uttarakhand (India) using nuclear simple sequence repeat (SSR) markers. By investigating 23 populations at 8 SSR loci, high genetic diversity (expected heterozygosity, He = 0.90; allelic richness, Ar = 13.65) was recorded with little genetic differentiation (fixation index, FST = 0. 025). Bayesian analysis revealed a weak genetic structure with no discrete genetic lineages from which ancestry can be inferred. Furthermore, genetic clustering among populations was conspicuous but not in accordance with their spatial distribution. Geographically separated populations are genetically well connected due to long-distance gene flow via pollen as well as seed. Hence, the meta-population in the Western Himalayas demonstrated a subtle spatial genetic structure with negligible genetic divergence, where genetic admixing is not modulated by geographical constraints. Viewing the substantial anthropogenic pressure over wild populations, conservation strategies must be adopted synergistically based on scientific knowledge. As center of diversity is centered toward the Kumaon region capturing higher allelic richness, we recommend the populations of this region to be prioritized for in situ conservation. Further, it will be important to harvest seeds from genetically diverse populations for raising plantations or ex situ field gene banks. As its fruits are mostly harvested from wild, local communities need to be sensitized and encouraged to establish private plantations or orchards. [ABSTRACT FROM AUTHOR]

Indian Mahogany (Toona ciliata, Family: Meliaceae) is a fast-growing and multi-purpose timber species. The species is well adapted to sub-tropical climates and generally grows in moisture-prone areas. It is frequently naturalized throughout the western sub-Himalayan tract, valleys of the outer Himalayas, and Eastern and Western Ghats and also cultivated on a fairly large scale in the plains of India, but no information about SSR-based genetic diversity and population structuring of T. ciliata in the Indian context has been available till now. Notably, population genetic analysis of T. ciliata is important for its long-term conservation, management, and genetic improvement programs. Thus, the present study was conducted to characterize natural populations of T. ciliata using simple sequence repeat (SSR) markers. In total, 444 individuals collected from 15 distant geographical locations in the western Himalayas were analyzed with 10 SSR loci. A total of 71 alleles were generated, with a mean of seven alleles, which ranged from 4 to 12 alleles for individual marker loci. Overall, a low level of genetic diversity (mean He = 0.315, range = 0.251–0.366) and high genetic differentiation (FST = 0.338) were recorded for the analyzed populations. Genetic clustering and STRUCTURE analysis revealed a strong genetic structure where most analyzed populations were grouped into two major clusters, indicating the existence of two gene pools. Further, the partitioning of genetic variance was significant (p ≤ 0.001) which revealed 34% of genetic variance among the populations. The Mantel test was used to estimate the genetic distance in relation to horizontal and altitudinal geographical distance, but a non-significant correlation was obtained. The results indicated that genetic distance between populations is not influenced by horizontal and altitudinal geographical distance. Overall, the study on population genetic analysis of T. ciliata will be of paramount importance to the researchers, foresters, and policymakers for guiding future conservation decisions. [ABSTRACT FROM AUTHOR]

Forests are considered as one of the most complex terrestrial ecosystems due to their high level of biodiversity, including genetic diversity. Understanding the genetic diversity of keystone species at a population level is vital to forest managers and policymakers for the conservation and sustainable utilization of forest genetic resources. Quercus semecarpifolia, commonly known as brown oak, is a keystone species of climax community thriving in the alpine zone of the Himalayas, which is presently experiencing population decline and range shift under the changing climate. In the present study, a landscape genetic approach was employed for deciphering the population genetic structure of Q. semecarpifolia in the western Himalayas using nuclear simple sequence repeat (SSR) markers. By analysing 718 individuals of 24 populations at 10 SSR loci, a high gene diversity (expected heterozygosity, He = 0.72; Allelic richness, Ar = 8.37) was recorded with a moderate genetic differentiation (FST = 0.16; P < 0.001). Genetic clustering and STRUCTURE analysis have displayed two major gene pools which appear to be primarily differentiated by the landscape and ecological constraints rather than the linear geographical distances. The hierarchical AMOVA analysis further supports the regional genetic divergence with a substantial proportion of genetic variation detected among the regions. Diversity maps generated by spatial interpolation elucidated the distribution pattern of genetic diversity and structure across the range, and aid in the demarcation of the diversity hotspots for conservation implications. To the best of our knowledge, this is the first comprehensive genetic study carried out in any Himalayan oaks, and the information generated herein is novel and of paramount importance in guiding conservation decisions. [ABSTRACT FROM AUTHOR]

The Grevillea robusta belonging to the family Proteaceae is proven to be a valuable and economically important timber species across its exotic distribution range in the world. The present research work aimed to establish the potential of regionally grown G. robusta as an alternative source of the wood-based industry. The wood quality standard tests and genetic evaluation of anatomical and physicochemical traits were conducted in the wood samples of G. robusta in northern India. The results on fiber length (FLmean = 1434.15 ± 7.58 µm) and fiber diameter (FDmean = 21.93 ± 0.18 µm) indicated that the species fall under the class II category of timber, though moderate heritability (H2 = 0.48) coupled with genetic advance (GA%of mean = 19.01%) was observed for the FD. The Runkle ratio (RR) showed moderate H2 (= 0.36) and high (GA%of mean = 31.77%) with a range varied from 0.40–0.82 (RRmean = 0.63 ± 0.01), which showed that the trait is probably governed by the genic action with the low influence of environment and thus, could be used in pulp and paper industries. Further, specific gravity (SG) varied from 0.41–0.61 with a mean of 0.53 ± 0.01 showing that the species was categorized under moderately heavy class (teak class), which is useful in veneer and furniture making. Also, moderate H2 (= 0.32) and GA%of mean(= 10.69%) were noted and selection could be effective for the trait SG. In addition to this, the low moisture content (MC = ~ 17%), moderate level of lignin content (LC = ~ 25%) and high holocellulose content (HC = ~ 75%) reveals that wood can be used for manufacturing kraft paper. Further, the genetic evaluation showed high heritability (0.82) both for LC and HC emphasizing that the tree improvement programme through selection could be applicable for G. robusta in the long-run for wood and timber of industrial applications. [ABSTRACT FROM AUTHOR]

Himalayacalamus falconeri is a socio-economically important temperate woody bamboo of north-western Himalayas, which has been investigated for genetic diversity and population genetic structure across distribution range in western Himalayas using genomic STMS markers. The calculated diversity measures have indicated a high gene diversity in H. falconeri at population level (Ho = 0.637; He = 0.714; Ar = 5.05). Despite the larger proportion of genetic variation (88%) confined within the populations, a moderate level of genetic differentiation (FST = 0.121) was detected with relatively lower gene flow (Nm = 1.891). Furthermore, clustering and STRUCTURE analysis displayed high genetic heterogeneity in a metapopulation, where populations in both the spatially disconnected regions of the Uttarakhand state, Garhwal and Kumaon, were clustered in different groups. Whereas, nested sub clustering and between-population genetic admixing were not correlated to their physical proximity. Also, the Mantel test supports the isolation by distance model showing a significant correlation between genetic and horizontal geographic distances. For conservation implications, diverse hotspots with high allelic richness were also identified in both the geographical regions of Uttarakhand state. To the best of our knowledge, it is a pioneer study presenting in depth knowledge of metapopulation in any Indian temperate bamboo, which will be of paramount importance to the researchers, foresters, and policymakers for guiding future conservation decisions of H. falconeri in the Indian Himalayan Regions (IHRs). [ABSTRACT FROM AUTHOR]

The present study was conducted to understand the key ecological and biological questions of conservation importance in Drepanostachyum falcatum which aimed to map potential distribution in the western Himalayas and decipher spatial genetic structure. Eco-distribution maps were generated through ecological niche modelling using the Maximum Entropy (MaxEnt) algorithm implemented with 228 geocoordinates of species presence and 12 bioclimatic variables. Concomitantly, 26 natural populations in the western Himalayas were genetically analysed using ten genomic sequence-tagged microsatellite (STMS) markers. Model-derived distribution was adequately supported with appropriate statistical measures, such as area under the 'receiver operating characteristics (ROC)' curve (AUC; 0.917 ± 0.034)", Kappa (K; 0.418), normalized mutual information (NMI; 0.673) and true skill statistic (TSS; 0.715). Further, Jackknife test and response curves showed that the precipitation (pre- and post-monsoon) and temperature (average throughout the year and pre-monsoon) maximize the probabilistic distribution of D. falcatum. We recorded a wide and abundant (4096.86 km2) distribution of D. falcatum in the western Himalayas with maximum occurrence at 1500 to 2500 m asl. Furthermore, marker analysis exemplified high gene diversity with low genetic differentiation in D. falcatum. Relatively, the populations of Uttarakhand are more genetically diverse than Himachal Pradesh, whereas within the Uttarakhand, the Garhwal region captured a higher allelic diversity than Kumaon. Clustering and structure analysis indicated two major gene pools, where genetic admixing appeared to be controlled by long-distance gene flow, horizontal geographical distance, aspect, and precipitation. Both the species distribution map and population genetic structure derived herein may serve as valuable resources for conservation and management of Himalayan hill bamboos. [ABSTRACT FROM AUTHOR]

Bamboo is an important genetic resource in India, supporting rural livelihood and industries. Unfortunately, most Indian bamboo taxa are devoid of basic genomic or marker information required to comprehend the genetic processes for further conservation and management. In this study, we perform genome survey sequencing for development of de novo genomic SSRs in Dendrocalamus longispathus, a socioeconomically important bamboo species of northeast India. Using Illumina platform, 69.49 million raw reads were generated and assembled into 1,145,321 contig with GC content 43% and N50 1228 bp. In total, 46,984 microsatellite repeats were mined-out wherein di-nucleotide repeats were most abundant (54.71%) followed by mono- (31.91%) and tri-repeats (9.85%). Overall, AT-rich repeats were predominant in the genome, but GC-rich motifs were more frequent in tri-repeats. Afterwards, 21,596 SSR loci were successfully tagged with the primer pairs, and a subset of 50 were validated through polymerase chain reaction amplification. Of these, 36 SSR loci were successfully amplified, and 16 demonstrated polymorphism. Using 13 polymorphic SSRs, a moderate level of gene diversity (He = 0.480; Ar = 3.52) was recorded in the analysed populations of D. longispathus. Despite the high gene flow (Nm = 4.928) and low genetic differentiation (FST = 0.119), severe inbreeding (FIS = 0.407) was detected. Further, genetic clustering and STRUCTURE analysis revealed that the entire genetic variability is captured under two major gene pools. Conclusively, we present a comprehensive set of novel SSR markers in D. longispathus as well as other taxa of tropical woody bamboos. [ABSTRACT FROM AUTHOR]

Tropical rainforests in Southeast Asia are enriched by multifarious biota dominated by Dipterocarpaceae. In this family, Shorea robusta is an ecologically sensitive and economically important timber species whose genomic diversity and phylogeny remain understudied due to lack of datasets on genetic resources. Smattering availability of molecular markers impedes population genetic studies indicating a necessity to develop genomic databases and species-specific markers in S. robusta. Accordingly, the present study focused on fostering de novo low-depth genome sequencing, identification of reliable microsatellites markers, and their validation in various populations of S. robusta in Uttarakhand Himalayas. With 69.88 million raw reads assembled into 1,97,489 contigs (read mapped to 93.2%) and a genome size of 357.11 Mb (29 × coverage), Illumina paired-end sequencing technology arranged a library of sequence data of ~ 10 gigabases (Gb). From 57,702 microsatellite repeats, a total of 35,049 simple sequence repeat (SSR) primer pairs were developed. Afterward, among randomly selected 60 primer pairs, 50 showed successful amplification and 24 were found as polymorphic. Out of which, nine polymorphic loci were further used for genetic analysis in 16 genotypes each from three different geographical locations of Uttarakhand (India). Prominently, the average number of alleles per locus (Na), observed heterozygosity (Ho), expected heterozygosity (He), and the polymorphism information content (PIC) were recorded as 2.44, 0.324, 0.277 and 0.252, respectively. The accessibility of sequence information and novel SSR markers potentially enriches the current knowledge of the genomic background for S. robusta and to be utilized in various genetic studies in species under tribe Shoreae. [ABSTRACT FROM AUTHOR]

Eucalyptus species are globally recognized and extensively planted hardwood trees whose flexibility, growth and diversity make them popular renewable sources of fibre and energy. Across the globe, the interest to create ways to develop significant hardwoods, like eucalypts, is rapidly growing. Although micropropagation offers a means to clonally propagate the desirable cultivars, the technique is often variety-specific for eucalypts. The present study aimed to expand our understanding of root initiation through macro-and-micropropagation in difficult to propagate superior full-sib matured hybrid (7-years-old trees) of eucalypts. Analysis of Variance (ANOVA) revealed that hormonal treatment of IBA (2,000–4,000 ppm) supplemented with Enterobacter sp. (106 cfu ml-1) significantly increased (p < 0.05) hybrid rooting through macropropagation. Notably, root initiation with maximum root development of 10.00% ± 0.91 and 3.75% ± 0.48 was observed at 3,000 ppm of IBA for hybrid genotypes FRI-PH3 (Corymbia torelliana × C. citriodora; 2A) and FRI-PH4 (E. pellita × E. urophylla; 1D), respectively. In the case of micropropagation studies, genotype FRI-4s (coppice shoots of E. tereticornis × E. camaldulensis, 10O) showed significant differences (p < 0.01) with various hormonal combinations (BAP, Kn and TDZ); and maximum number of shoot (4.0 ± 0.82) proliferation with average shoot length of 2.5 ± 0.15 cm was recorded in 0.5 mg L-1 BAP, ½ MS medium and 0.5 mg L-1 Kn in accordance to Duncan Multiple Range Test (DMRT). Afterward, for in vitro rooting, ¼ MS medium fortified with 1.0 mg L-1 IBA was proved to be the optimal medium for root induction, the maximum number of roots per explant (5.0 ± 0.91) with an average root length of 3.10 ± 0.15 cm was observed. Overall, the study signifies successful macro-and-micropropagation of mature eucalyptus hybrids through branch cuttings and nodal segments. [ABSTRACT FROM AUTHOR]

The Himalayan region is not only threatened by rapid anthropogenic activities but also by the effects of global climate change. Given the uncertainties in magnitude and characteristics of climate change, it is of crucial importance to accumulate prior knowledge of existing and the adaptive future change in the distribution pattern of tree species, especially in the Himalayas which are pronounced with highly heterogeneous ecology. Quercus semecarpifolia, a high-altitude Oak, ranges up to timberline in the Himalayan region. This species forms the climax community on the southern aspect of the mountainside, and is considered to be one of the oldest trees belonging to the Himalayan region. Due to climate-influenced phenomena like masting and inherently slow growth rate, this dominant species is under severe decline. Hence, the present study aimed to delineate and predict the potential distribution range of Q. semecarpifolia in the Uttarakhand region of northwestern Himalayas in relation to associated species, land use land cover, wind, edaphic and bioclimatic variables. Furthermore, potential spatio-temporal variations within the purview of climate change were also predicted through MaxEnt modelling. In total, 589 geo-coordinates were recorded during field surveys (2016–2021) that cover a wide-range of slope, aspect and elevation. Over the WorldClim dataset, ~ 70% well-distributed geo-coordinates were used for training the model and the remaining for validation. The model performance was supported by statistically significant and high AUC value of 0.943 ± 0.059; whereas, the Jackknife test showed that bioclimatic variables, namely annual temperature range (Bio 7), precipitation of the driest month (Bio 14), minimum temperature of the coldest month (Bio 6), and mean temperature of the coldest quarter (Bio 11) contributed significantly in predicting the current distribution of Q. semecarpifolia. The species is majorly distributed in a total of 29 sites belonging to nine districts (dominated in Pithoragarh, Chamoli and Uttarkashi) with altitude ranging from 2249 (Ghes) to 3652 m (Karandam Bugyal). The distribution was further overlaid on KGCC map, which showed maximum occurrence in Cwb (C = warm temperate, w = winter dry, and b = warm summer), i.e., subtropical highland oceanic climate of middle and upper Himalayas constituted by the northwestern Bageshwar, southern Chamoli, small stretch of northeastern Pauri, southeastern Rudraprayag, northern Tehri and Uttarkashi. In the study area, Q. semecarpifolia has been observed to be associated with 19 tree species, where the highest density ratio was recorded with Rhododendron arboreum. The MaxEnt model-based prediction revealed an area of ~ 832 km2 with the loss of ~ 79 km2 (RCP 8.5_2050) and ~ 168 km2 (RCP 8.5_2070), in advancing upslope of the northwestern Himalayas. Geological analysis indicated that tectonic uplift, an important control to the altitudinal shift modelled for the distribution of Q. semecarpifolia due to time scale divergence. Bedrock composition variations, however, might control distribution by means of influencing soil acidity. This study predicts an upslope movement of Q. semecarpifolia in response to climate change where topography and climatic factors could play a significant role. [ABSTRACT FROM AUTHOR]

Proteaceae, a largely southern hemisphere family consisting of 80 genera distributed in Australia and southern Africa as its centres of greatest diversity, also extends well in northern and southern America. Under this family, Grevillea robusta is a fast-growing species got popularity in farm and avenue plantations. Despite the ecological and economic importance, the species has not yet been investigated for its genetic improvement and genome-based studies. Only a few molecular markers are available for the species or its close relatives, which hinders genomic and population genetics studies. Genetic markers have been intensively applied for the main strategies in breeding programs, especially for the economically important traits. Hence, it is of utmost priority to develop genomic database resources and species-specific markers for studying quantitative genetics in G. robusta. Given this, the present study aimed to develop de novo genome sequencing, robust microsatellites markers, sequence annotation and their validation in different stands of G. robusta in northern India. Library preparation and sequencing were carried out using Illumina paired-end sequencing technology. Approximately, ten gigabases (Gb) sequence data with 70.87 million raw reads assembled into 425,923 contigs (read mapped to 76.48%) comprising 455 Mb genome size (23 × coverage) generated through genome skimming approach. In total, 9421 simple sequence repeat (SSR) primer pairs were successfully designed from 13,335 microsatellite repeats. Afterward, a subset of 161 primer pairs was randomly selected, synthesized and validated. All the tested primers showed successful amplification but only 13 showed polymorphisms. The polymorphic SSRs were further used to estimate the measures of genetic diversity in 12 genotypes each from the states of Punjab, Haryana, Himachal Pradesh and Uttarakhand. Importantly, the average number of alleles (Na), observed heterozygosity (Ho), expected heterozygosity (He), and the polymorphism information content (PIC) were recorded as 2.69, 0.356, 0.557 and 0.388, respectively. The availability of sequence information and newly developed SSR markers could potentially be used in various genetic analyses and improvements through molecular breeding strategies for G. robusta. [ABSTRACT FROM AUTHOR]

Salvadora oleoides is a keystone and economically important species in the desert biome of the Indian subcontinent. However, species decline has been observed during field surveys (2016–2019) conducted in the Indian states of Punjab, Haryana, Rajasthan and Gujarat. For species distribution mapping, geospatial data of 683 trees were recorded, out of which 70.28% were used for training and the rest to validate the MaxEnt model. The statistically significant AUC value ranged from 0.92 ± 0.02 (LGM) to 0.93 ± 0.01 (RCP 2.6_70) with an average of 0.92 ± 0.00. The bioclimatic variables, namely precipitation of warmest quarter (Bio 18), annual precipitation (Bio 12), altitude (Alt), precipitation of wettest month (Bio 13), precipitation of coldest quarter (Bio 19) and maximum temperature of warmest month (Bio 5), contributed significantly for predicting the species distribution, which ranged from 60.3% (Last Glacial Maximum, LGM) to 85.5% (Current) with an average of 75.82%. For the climate change scenario (2050s and 2070s), a sharp decline in the species distribution area was observed for all RCPs (when compared with the current estimate of 8638.01 km2), which ranged from 2102.90 (RCP 2.6_70) to 5494.23 km2 (RCP 8.5_70). The model output revealed that the distribution is in accordance with the Köppen-Geiger climate classification system and the geological map of northwestern India. In relation to the geological variables, distribution of S. oleoides occurrence is conditioned to the presence of calcium-rich bedrock, which is used as a mechanism of compensation for the high salinity of desert soils. Overall, the study provides an eco-geo-distribution map and the potential use of MaxEnt in prediction modelling of the species. Furthermore, the research led to insights for suitable conservation and management plans for S. oleoides in arid zones of south Asian sub-continental climatic conditions. [ABSTRACT FROM AUTHOR]

Drepanostachyum falcatum (Nees) Keng f. is one of the most widely distributed shrubby bamboo species in the temperate region of northwest (NW) Himalayas. Along with the other three temperate bamboo species, namely Yushania anceps, Thamnocalamus spathiflorus and Himalayacalamus falconeri, commonly called as 'ringal', and utilized for making various articles of household and commercial purpose by local artisans. Despite huge ecological and socio-economic importance, they are least studied and lacks baseline genetic information. In this study, ~10 Gb genome sequence data with 70.68 million reads were generated for D. falcatum, through genome skimming approach based on high throughput next-generation sequencing technology with Illumina protocol. The high-quality reads were de novo assembled into 31,997 contigs, which comprised 1943 microsatellite repeats. The dinucleotide and trinucleotide repeats were most abundantly distributed in the genome with 52.95 and 41.17%, respectively. Depending on the sufficient flanking sequence, only 1123 repeats were successfully tagged with primer pairs and these sites were designated as sequence-tagged microsatellite (STMS) markers. Further, a subset of 106 STMS markers were validated through PCR amplification; 77 marker loci were successfully amplified, and 48 of these showed polymorphism. Same set of marker loci were also tested for their cross-amplification in other three temperate bamboo species of the NW Himalayas, which revealed good level of transferability (27-48%) but lesser polymorphism (4-12%). In addition, the genomewide in silico cross-amplification revealed poor cross-transferability in other bamboo taxa representing four different phylogenetic lineages, namely Phyllostachys edulis (10.2%), Bonia amplexicaulis (3.03%), Guadua angustifolia (1.60%), Olyra latifolia (0.89%) and Raddia guianensis (0.36%). Ten polymorphic markers were further used to estimate the measures of genetic diversity in two natural populations, which revealed high genetic diversity (polymorphic information content, PIC = 0.889; expected heterozygosity, He = 0.756) and low genetic differentiation (FST=0.061; Nm = 5.445). To the best of our knowledge, this is one of the pioneer studies carried out for the development of genomic STMS markers through genome skimming approach in Indian bamboo species. The marker information generated here is novel and of paramount importance for future genetic studies in D. falcatum as well as other temperate bamboo species through cross-transferability. [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the discriminatory potential of selected chloroplast-based DNA barcode regions for identifying and resolving phylogeny of the Indian bamboos. Among 11 chloroplast markers screened, only four, namely matK, rbcL, psbK-I and rps16-trnQ showed successful amplification in 88 genotypes of 30 Indian bamboo taxa under Bambuseae and Arundinarieae tribes. A total of 244 sequences were generated for the four chloroplast regions. Tree-based analysis demonstrated that none of the tested regions successfully discriminated the taxa under Bambuseae tribe. Importantly, our highly concerned Himalayan temperate bamboo species under Arundinarieae tribe, were successfully discriminated by matK locus with high bootstrap support (>60%). Sequence comparisons revealed that the discriminatory power demonstrated by matK region actually lies in the few unique fixed nucleotides (UFNs) despite the overall DNA polymorphism. Although, rps16-trnQ region was found to be the most polymorphic and revealed high genetic divergence among different taxonomic levels, it could not successfully discriminated the taxa with strong statistical support. In a taxonomically difficult plant group like bamboos, whose genome is relatively more complex and has a slow rate of molecular evolution, it is difficult to get a universal marker. Further, highly variable barcode regions utilized in other species may not be informative, and thus, the development of DNA barcodes for different taxonomic levels, such as lineages or tribes could be a viable approach. [ABSTRACT FROM AUTHOR]

Populus deltoides is a fast-growing woody species possessing plethora of industrial applications. This species evolutionarily developed unisexual male and female catkin inflorescence on separate trees. Flowering usually occurs during early spring before the development of foliage, where buds appear near axils or at the extending shoots. In 2019, surveys were undertaken to study the flowering pattern of P. deltoides in the states of Punjab, Haryana, Uttar Pradesh and Uttarakhand in northern India. Interestingly, an anomalous flowering behaviour (appearance of off-season male catkins during autumn, i.e. October) was observed in a plantation trial at Kapurthala, Punjab. The male catkins were 2.7–3.1 ± 0.07 cm long and 0.3–0.5 ± 0.03 cm wide, which is significant for flowering and liberation of pollen grains. Preliminary results suggested that climatic factors, such as episodes of high or low temperature and the precipitation variation forcing the tree species to behave differently. Unearthing the climate-driven off-season flowering in other tree species alluded the stimulation of phytohormones, such as gibberellic and salicylic acid concentrations influencing the flowering time, therefore, needs further investigation in case of P. deltoides. Overall, this work provides early clues of changing climatic scenario altering the flowering pattern of a tropical forestry tree species. [ABSTRACT FROM AUTHOR]

Salvadoraceae constitutes ecologically imperative desert families of 3 genera—Azima, Dobera and Salvadora. Under genus Salvadora of this family, S. oleoides is a keystone species of socio-economic and medicinal value. This species naturally grows in the arid zones but currently experiencing severe fragmentation due to land use change and reduced regeneration, which may have resulted in the depletion of genetic diversity. Hence, it is up-most important to develop genomic resources for studying the population genetics in S. oleoides. This study aims to develop robust microsatellites markers, which were not yet reported in genus Salvodora due to lack of genome sequence information. We developed novel microsatellites markers in S. oleoides using Illumina paired-end sequencing technology. In total, 14,552 simple sequence repeat (SSR) markers were successfully designed from 21,055 microsatellite repeats detected in the 13 Gb raw sequence data. Afterwards, a subset of 101 SSRs were randomly selected and validated, 94 primers were successfully amplified and 34 showed polymorphisms. These SSRs were used to estimate the measures of genetic diversity in three natural populations of state Rajasthan and Gujarat. Importantly, average number of alleles (Na), observed heterozygosity (Ho), expected heterozygosity (He), and polymorphism information content (PIC) were recorded as 2.4, 0.529, 0.357, and 0.326, respectively. Furthermore, 15 primers were evaluated in S. persica for cross-transferability, and all were successfully amplified but only eight showed polymorphisms. This study has been conducted first time for S. oleoides and pioneer among the native species of arid-zone in India. [ABSTRACT FROM AUTHOR]

In the middle Himalayas, Rhododendron arboreum is shrinking due to low seed viability, poor regeneration, habitat degradation and fragmentation, habitat distortion, and species invasion. Further, developmental activities, the encroachment of forestland for agriculture, urbanization, and industrial expansion put additional burdens on its natural distribution. The present work focused on the prediction of R. arboreum distribution in Uttarakhand Himalayas using the Maxent model. In total, 1077 geospatial data were recorded, 300 well-distributed geo-coordinates were used to predict and estimate the distribution, while the rest were used to validate the model. The Maxent model generated AUC curve with an accurate and significant value of 0.886 ± 0.023. Bioclimatic variables such as temperature seasonality (Bio 4), annual temperature range (Bio 7), altitude (Alt), annual precipitation (Bio 12), and precipitation seasonality (Bio 15) contributed significantly to predict the distribution, as revealed by the Jackknife test. Within the total geographical area of 617.48 km2 under R. arboreum distribution as shown over Landsat 8 generated map, 167.48 km2 was found to be very dense, 320.75 km2 was moderately dense, and 129.25 km2 was open. The estimated distributed area was 2733.08 km2. The satellite-based mapping and model-based prediction of R. arboreum are of paramount importance to the foresters and researchers for species conservation, management, and utilization in a sustainable manner. [ABSTRACT FROM AUTHOR]

Sawadaea, Powdery mildew, Phylogenetic analysis, Pathogen, Aesculus Keywords: Sawadaea; Powdery mildew; Phylogenetic analysis; Aesculus; Pathogen EN Sawadaea Powdery mildew Phylogenetic analysis Aesculus Pathogen 1179 1179 1 09/15/23 20230801 NES 230801 Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s42161-023-01382-5. [Extracted from the article]

Keywords: Oxalis debilis; Puccinia oxalidis; Rust; New host EN Oxalis debilis Puccinia oxalidis Rust New host 453 453 1 02/24/22 20220201 NES 220201 Supplementary information The online version contains supplementary material available at https://doi.org/10.1007/s42161-021-01013-x. ( I O. corniculata i , I O. corymbosa i , I O. dehradunensis i and I O. latifolia i ) are well-known host for I P. oxalidis i (Farr and Rossman [1]; Verma et al. [3]). [Extracted from the article]

In this study, Calonectria eucalyptorum sp. nov. is described from the blighted leaves of Eucalyptus in India using morphological and multi-locus phylogenetic analyses. The new species belongs to the Calonectria cylindrospora species complex, and its unique microscopic features and DNA sequence information enable clear separation from the 12 currently accepted species in this complex. Conidia of the new taxon are slightly longer than those of its phylogenetic neighbors. Additionally, this species produces central as well as lateral stipe extensions, which is a feature not known for the other members of the C. cylindrospora species complex. Analyses of the combined partial calmodulin, histone, translation elongation factor-1α, and β-tubulin gene regions revealed a distinct phylogenetic position for C. eucalyptorum. Recombination analysis provided additional support for the new species hypothesis. Koch's postulates for the new taxon as a foliar pathogen of Eucalyptus were fulfilled. The discovery of novel and pathogenic Calonectria species is important because it sheds light on species diversity, potential threats, and disease control., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)