Economic Plants Research Articles

Distribution of Charcoal Rot of Soybean, its Influencing Factors and Pathogenic Variabilities in Different Regions of Madhya Pradesh

Background: Macrophomina phaseolina (Tassi) Goid is a necrotrophic soil-inhabiting fungus that causes disease in several economic plants worldwide and has now become a serious threat to soybean cultivation in central India. Methods: The random surveys were done during 2018 and 2019 to determine the present status of charcoal rot (M. phaseolina) in key soybean growing districts of Madhya Pradesh. Sixteen isolates of pathogen were characterized based on morpho-cultural and pathogenic variability by using cut stem inoculation techniques at J.N.K.V.V., Jabalpur. Result: Charcoal rot was prevalent in all surveyed sixteen districts of Madhya Pradesh. Out of six, Kymore plateau and Satpura hills (44.5%), Satpura plateau (42.5%), Central Narmada Valley (42.0%) and Vindhyan plateau agroclimatic zones (35.0%) were identified as favouable zones for charcoal rot. Malwa plateau (16.25%) and Northern hill region (24.5%) had low incidences of charcoal rot. Among varieties, JS 95-60, JS 93-05 and JS 20-29 were highly affected, whereas, JS 20-34, JS 20-98 and JS 20-69 were least affected. Incidence of charcoal rot was comparatively higher in the fields that had Maize-Chickpea (26.32%), Maize-Wheat, Soybean- Pea and Soybean - Chickpea cropping patterns in the previous year and lowest in Rice-Chickpea (12.00%) and Rice - Wheat (12.45%) cropping patterns. The incidence of charcoal rot was partially higher in the fields with light soil (21.3%) than in heavy soil (19.0%). Isolates investigation revealed that isolates from Jabalpur, Hoshangabad, Chhindwara and Sagar were fast-growing variables and highly aggressive in developing necrotic lesions on the cut stem of soybean. This investigation could be instrumental in forewarning sensitive areas of charcoal rot, varietal options and crop rotation to be followed to minimize the incidence of charcoal rot. Moreover, identified variable aggressive isolates could be utilized in genotype resistance screening programs.

Ektaphelenchoides factum n. sp. in Pinus taeda from the USA and E. pini in Pinus koraiensis from China

Summary The genus Ektaphelenchoides is a diverse group of nematodes; they are either inhabitants of trees or present in the rhizosphere of economical plants. Members of the genus have ecological relevance in terms of being associated with insects and predators of other nematodes. In the present study, a new Ektaphelenchoides species, E. factum n. sp., is described and illustrated. The new species was isolated from a log sample of Pinus taeda imported from the USA. It is characterised by the lateral field with three incisures, stylet distinctly tripartite. Females having a vulval flap, the anus and rectum indistinct, and the tail (posterior part of body) filiform. Males having arcuate and 21.5 (19.4-22.9) μm long spicules, the lamina of the spicule is smoothly curved to distal end, condylus well developed with a broadly rounded tip, rostrum triangular with finely rounded tip and cucullus absent, tail arcuate and conical with terminus bearing a sharply pointed mucron. The new species is different from other Ektaphelenchoides species in having a vulval flap. Molecular characterisation and phylogenetic studies also supported its unique status. In addition, a Chinese native population of E. pini, detected in Pinus koraiensis branches from Liaoning province, P.R. China, is described.

Cultivating the Hills and the Sands: A Comparative Archaeobotanical Investigation of Early Islamic Agriculture in Palestine

ABSTRACT This article investigates how agricultural choices were driven by political, social and environmental conditions in Palestine during the Early Islamic period (c. 636–1099 CE) through the analysis of charred archaeobotanical assemblages from three archaeological sites in the southern Levant. These sites – the coastal urban centres of Ashkelon and Caesarea Maritima, and the large inland village of Neby Zakaria – are situated in different environmental settings and had distinct socioeconomic functions. Data on categories of economic plants (cereals, chaff, pulses, fruits and nuts) are aggregated from all time periods represented at each site to understand general patterns of crop presence and are examined diachronically. These data show that the production and consumption of plant resources were affected more by a settlement’s socioeconomic function than by its environmental setting; in this case, urban centres specialised in perennial arboriculture and viticulture, and villages specialised in annual cultivation of cereals and pulses. Furthermore, these data suggest that there is no clear divide between cities as consumers or conduits of trade and villages as producers of agricultural products in this part of Palestine in the Early Islamic period, but this pattern needs to be tested with archaeobotanical investigations of additional sites.

Analysis of Pollen in Stingless bee (Meliponula ferruginae [ Moure]) Honey, an Indicator of Deforestation Levels at University of Ilorin and its Environs

Pollen analysis of the honey of stingless bees was conducted to ascertain the levels of deforestation in the campus of the University of Ilorin, North Central Nigeria. Thirteen honey samples from the nests of Meliponula ferruginae in four different localities, with varied deforestation levels, in the University of Ilorin Agro-Ecological areas were analysed. Pollen grains were identified and counted under high power light microscope. Species diversity assessed using Shannon diversity index, species richness and dominance of the floral origin of the pollen were calculated using PAST Software. A total of 43 pollen types belonging to 26 families, and a fungal spore, Lasiodiplodia theobromae, were recovered. Twenty-four pollen types were recovered from samples from Bolounduro and Oyun, both slightly disturbed agro-ecological areas; 14 pollen types were from the Senior Staff Quarters, a slightly disturbed agro-ecological area bordered with date palm plantation and twenty-six pollen types were from Jalala, a highly disturbed agro-ecological area. The most dominant pollen types namely Hymenocardia acida, Lannea sp., Elaeis guineensis, Alchornea sp., Vitellaria paradoxa, Entada abyssinica and Parkia biglobosa indicated that the study area was Guinea savanna. The honey samples from the slightly disturbed localities yielded pollen of open/secondary forest while those from the highly disturbed locality yielded an array of the pollen of economic plants and herbs characteristic of anthropogenic disturbance. The honey samples from all the sites showed high diversity of pollen types. Polyflora honey with high Shannon-Weiner Diversity index and monoflora with low Shannon-Weiner Diversity index were observed in all the sites except at Bolounduro where monoflora with high Shannon-Weiner Diversity index was observed.

Genome-wide analysis and functional validation reveal the role of late embryogenesis abundant genes in strawberry (Fragaria × ananassa) fruit ripening

BackgroundLate embryogenesis abundant (LEA) proteins play important roles in plant growth and development, as well as stresses responsiveness. Nowadays, it has been found that LEAs also have function in fruit ripening. However, the comprehensive analysis on a genome-wide basis of LEA family remains limited, and the role of LEA in fruit ripening has not been fully explored yet, especially in strawberry, an economic important plant and ideal material for studying fruit ripening.ResultsIn this study, a total of 266 putative LEA proteins were identified and characterized in strawberry genome. Subcellular localization prediction indicated that they were mostly localized in chloroplast, cytoplasm and nucleus. Duplication events detection revealed that whole genome duplication or segmental was the main driver for the expansion of LEA family in strawberry. The phylogenetic analysis suggested that FaLEAs were classified into eight groups, among which, LEA2 was the largest subgroup with 179 members, followed by LEA3, dehydrin (DHN), LEA4 and SMP (seed maturation protein). The LEA1 and DHN groups were speculated to play dominant roles in strawberry fruit development and ripening, according to their larger proportion of members detected as differentially expressed genes during such process. Notably, the expression of FaLEA167 belonging to LEA1 group was altered by strawberry maturation, and inhibited by overexpression of negative regulators of ripening (a cytosolic/plastid glyceraldehyde-3-phosphate dehydrogenase, FaGAPC2 and a cytosolic pyruvate kinase, FaPKc2.2). Subsequently, overexpression of FaLEA167 significantly increased the percentage of fruit at green stage, while reduced the full red fruit proportion. In consistent, the anthocyanins content and the fruit skin color variable reflecting a range from greenness to redness (a* value) were significantly reduced. Whereas, FaLEA167 overexpression apparently up-regulated citric acid, soluble protein and malondialdehyde content, but had no obvious effects on total soluble solids, sugar, flavonoids, phenolics content and antioxidant capacity.ConclusionsThese findings not only provided basic information of FaLEA family for further functional research, but also revealed the involvement of FaLEA167 in negatively regulating strawberry fruit ripening, giving new insights into understanding of FaLEA functions.

A Phylogenetic and Taxonomic Revision of Discula theae-sinensis, the Causal Agents of Anthracnose on Camellia sinensis.

Tea (Camellia sinensis (L.) Kuntze) is one of the most important economic plants in China, and has many benefits for human health. Anthracnose is one of the most serious diseases of tea in China, and control of the fungus is important since most Chinese cultivars are susceptible to it. The agent of tea anthracnose was initially described as Gloeosporium theae-sinensis I. Miyake in Japan, which was later transferred to Discula, but this taxonomic position remains problematic. To shed light on these taxonomic and phylogenetic issues, the tea anthracnose pathogens were re-studied. Combining the morphological characteristics and a multigene phylogenetic analysis of nrITS, nrLSU, rpb2, and tef1 sequence data, a new genus Sinodiscula was proposed to accommodate the causal fungi of tea anthracnose, including a new species Sinodiscula camellicola and a new combination Sinodiscula theae-sinensis. Furthermore, the pathogenicity of the pathogens was determined according to Koch's postulates. This study thoroughly resolves the long-standing taxonomic and phylogenetic problems of the tea anthracnose pathogens.

Studies of the Indigenous Edible Wild Fruits of Etche Local Government Area, Rivers State, Nigeria

In the past, Indigenous Edible Wild Fruits (IEWFs) were vital source of food and nutrition in Etche Local Government Area. These plant species were highly nutritious and assisted in poverty alleviation and enhanced food security in Etche. Presently, due to the teeming population and the anthropogenic activities in the area especially the farming practice of the local people, the availability and rate of consumption of the IEWFs have been negatively impacted. Information about these economic plant species that are domiciled in Etche has not been properly documented. This investigation seeks to fill the gap. IEWFs were identified in ten (10) study area communities. Scientific names, common names, local names, families, habits, habitat and locality of the plants were documented. It was observed that 36 plant species drawn from 29 genera, representing 23 families were Indigenous Edible Wild Fruits consumed regularly by Etche people. The study revealed that the fruit plants were 39% trees, 42% shrubs, 8% herbs and 11% climbers. In addition, most of the edible plant species in the area were exclusively found in the wild while a few were domesticated and some of them served as a source of income for some households. The study observed a decline in the diversity of species due to depletion of forest resources through bush burning, deforestation and exploitation of flora by the rural dwellers for other purposes.

Comprehensive analysis of WOX transcription factors provide insight into genes related to the regulation of unisexual flowers development in Akebia trifoliata

Akebia trifoliata is a fascinating economic and medicinal plant that produces functionally unisexual flowers due to stamen/pistil abortion during flower development, and the genetic regulation pathway of this process remain completely unknown. Here, 10 AktWOXs were identified for the first time, all contained a highly conserved homeodomain. AktWOXs were divided into three clades, each with the same or similar intron, exon, and motifs distribution. Many cis-elements related to stress response, growth and development, and hormone response were found in the AktWOXs promoter region. In addition, four candidate genes AktWOX8, AktWOX11, AktWOX13.2 and AktWUS that might be involved in unisexual flowers development were screened, all of which were located in the nucleus and showed transcriptional activation activity. Yeast one-hybrid showed that both AktKNU and AktAG1, the potential core transcription factors in the activity termination pathway of flower meristem stem cells, could bind to the promoter region of AktWUS. Dual-luciferase assay further confirmed that only AktKNU inhibited the expression of AktWUS. Collectively, this study revealed the mechanism of AktWUS that might affect the formation of unisexual flowers by regulating the timely termination of flower meristem in A. trifoliata.

The impact of nitrogen fertilization on the alkaloid content and growth traits of Datura (Datura stramonium L.)

D. stramonium is a wild plant species belonging to the nightshade family Solanaceae and grows on the edges of cotton fields, empty lands and roadsides. The plant is one of the most important economic weed plants that contain both toxic and medicinal properties. Studies have shown that the plant contains toxic tropane alkaloids such as atropine, hyoscyamine, and scopolamine. It is known that cultivation techniques have a great influence on the quality and quantity of secondary metabolites. For this reason, it is important to determine the optimal values of the agronomic factors that influence plant growth and production. This study was conducted in the experimental area of the Agricultural Faculty of Dicle University in the 2010 and 2011 growing seasons so as to evaluate the impact of nitrogen fertilizer rates (0, 50, 100 and 200 kg ha-1) on some agronomical characteristics such as fresh and dry herb yield and total alkaloid content of Datura (Datura stramonium L.). The results revealed that significant (P?0.05) differences were observed between nitrogen doses in the 2010 and 2011 growing seasons in terms of seed yield, fresh and dry herb yield and total alkaloid yield of seeds. However, seed yield changed between 545 kg ha-1 and 625 kg ha-1, fresh herb yield between 8000 and 24483 kg ha-1, dry herb yield between 2190 kg ha-1 and 5083 kg ha-1 and alkaloid content between 0.259% and 0.366%, respectively. The results showed that fresh and dry herb yields increased with increasing nitrogen doses.

Effect of different pretreatments of Aquilaria malaccensis seeds for enhancement of germination rate

A few plant species of the Thymelaeceae family are highly valuable and demanding because they contain resinous oil in their stems, branches, and roots. From this plant, resinous oil is extracted through the distillation process. Traditionally and from the religious point of view, the oil has a higher potential in the manufacturing of perfume, incense sticks, smoke, and many other medicinal and religious purposes. It is a highly economic plant, so its conservation is very important. Aquilaria plants are propagated through seeds and the seeds are recalcitrant, i.e., they are chilling sensitive and also cannot be stored at room temperature because of their high moisture content. They are also called desiccation sensitive. Below a certain level of moisture content, their embryos become death or inviable. Conservation of germplasm in the case of recalcitrant seeds is a major issue to be solved in the current situation. Our main focus was to enhance the germination of the Aquilaria malaccensis seeds for the early development of the seedlings within a short time. Here we are applying different pretreatments of Aquilaria seeds, such as Acetone for 1 min, 2 min, and 3 min, likewise Methanol, Ethanol, hot water, acetic acid, etc for enhancing seeds germination and it was found that highest germination percentage in the treatment where seeds are soaked in 1 min acetone (70%) in comparison to the control, which shows only a 56.7% germination rate. Their germination rate was determined by regular observation for up to 2 months, and the growth curve was also prepared by calculating the weight of the seeds. The findings of the current study will help to develop a protocol for early germination as well as mass propagation within a short period of time. The results of the Aquilaria species are significantly different from each other.

The RNA landscape of Dunaliella salina in response to short-term salt stress.

Using the halotolerant green microalgae Dunaliella salina as a model organism has special merits, such as a wide range of salt tolerance, unicellular organism, and simple life cycle and growth conditions. These unique characteristics make it suitable for salt stress study. In order to provide an overview of the response of Dunaliella salina to salt stress and hopefully to reveal evolutionarily conserved mechanisms of photosynthetic organisms in response to salt stress, the transcriptomes and the genome of the algae were sequenced by the second and the third-generation sequencing technologies, then the transcriptomes under salt stress were compared to the transcriptomes under non-salt stress with the newly sequenced genome as the reference genome. The major cellular biological processes that being regulated in response to salt stress, include transcription, protein synthesis, protein degradation, protein folding, protein modification, protein transport, cellular component organization, cell redox homeostasis, DNA repair, glycerol synthesis, energy metabolism, lipid metabolism, and ion homeostasis. This study gives a comprehensive overview of how Dunaliella salina responses to salt stress at transcriptomic level, especially characterized by the nearly ubiquitous up-regulation of the genes involving in protein folding, DNA repair, and cell redox homeostasis, which may confer the algae important mechanisms to survive under salt stress. The three fundamental biological processes, which face huge challenges under salt stress, are ignored by most scientists and are worth further deep study to provide useful information for breeding economic important plants competent in tolerating salt stress, other than only depending on the commonly acknowledged osmotic balance and ion homeostasis.

Effect of electrolyte additives derived from natural plant extracts - Hibiscus Sabdariffa &Bidens Pilosa, on electrochemical performance of a lead-acid battery

Lead-Acid Batteries (LABs) remain a popular choice for energy storage due to their wide availability and reasonably low cost, but they exhibit a shorter cycle life and are non-eco-friendly. The objective of this study was to evaluate the discharge capacity of a flooded lead-acid battery using an electrolyte modifiedwith additives from natural plant extracts -Hibiscus Sabdariffa (H–S) and Bidens Pilosa (B–P) plants. The study utilized commercial LABs with electrolyte solutions of 100% sulfuric acid and varying volumes of plant extract solutions at concentration of 10% (w/v), 15.86% (w/v), 30% (w/v) and 44.14% (w/v). The effect of the additives was assessed by comparing the charge-discharge cycle times, coulombic efficiency and energy efficiency. The results show the longest measured discharge time of 4.63 h at 15.86% (w/v) of H–S additive-electrolyte solution, 0.13 h longer than for the standard electrolyte. The highest coulombic efficiency (CE) was 97.3% at 44.14% (w/v) of H–S additive electrolyte solution, 10% above the standard electrolyte. The highest value for energy efficiency (EF) was 83.8% achieved in the battery with 44.14% (w/v) H–S additive electrolyte solution. The best recorded performance with B–P additive electrolyte solution was, CE of 94.6% and EF of 81.3%, obtained at 15.86% (w/v) additive concentration. It is evident from the results that bio-active compounds present in the additive solution of plant extracts influenced the electrochemical performance of the battery. The novelty of this work lies in the choice of candidate plants named, H–S and B–P for green extracts and the methodology of extraction, which is low-cost, eco-friendly and sustainable. This study contributes to fundamental understanding and strategies towards economical and eco-friendly plant electrolyte batteries.

Unprecedented yet gradual nature of first millennium CE intercontinental crop plant dispersal revealed in ancient Negev desert refuse.

Global agro-biodiversity has resulted from processes of plant migration and agricultural adoption. Although critically affecting current diversity, crop diffusion from Classical antiquity to the Middle Ages is poorly researched, overshadowed by studies on that of prehistoric periods. A new archaeobotanical dataset from three Negev Highland desert sites demonstrates the first millennium CE's significance for long-term agricultural change in Southwest Asia. This enables evaluation of the 'Islamic Green Revolution (IGR)' thesis compared to 'Roman Agricultural Diffusion (RAD)', and both versus crop diffusion during and since the Neolithic. Among the findings, some of the earliest aubergine (Solanum melongena) seeds in the Levant represent the proposed IGR. Several other identified economic plants, including two unprecedented in Levantine archaeobotany-jujube (Ziziphus jujuba/mauritiana) and white lupine (Lupinus albus)-implicate RAD as the greater force for crop migrations. Altogether the evidence supports a gradualist model for Holocene-wide crop diffusion, within which the first millennium CE contributed more to global agricultural diversity than any earlier period.

Improvement of Culture Conditions and Plant Growth Regulators for In Vitro Callus Induction and Plant Regeneration in Paeonia lactiflora Pall.

Owing to its high ornamental, medicinal and horticultural values, herbaceous peony (Paeonia lactiflora Pall.) has been widely used as a landscaping and economical plant around the world. However, the lack of an efficient and stable regeneration system in P. lactiflora restricts its rapid propagation and large-scale production. By testing the key factors affecting callus formation, proliferation, adventitious bud induction and rooting, here, we developed an in vitro system for callus induction and regeneration in P. lactiflora. Our results show that callus formation was affected by explant types, culture environment, basal medium and plant growth regulators. Using cotyledons as explants, we established good conditions for P. lactiflora callus induction and callus proliferation. We effectively obtained adventitious buds differentiated from callus in Murashige and Skoog (MS) medium containing kinetin (KT) and thidiazuron (TDZ). Adventitious bud growth can be further promoted by adding gibberellin 3 (GA3), 1-naphthaleneacetic acid (NAA) and 6-benzyleaminopurine (6-BA) into the MS medium. A high percentage of rooting can be achieved by adding indolebutyric acid (IBA) and activated carbon (AC) to ½ MS medium. Overall, our system promotes callus induction and adventitious bud regeneration for P. lactiflora through improved culture conditions and plant growth regulators in the culture media, and lays a foundation for subsequent genetic engineering research.

Assessment of Wave Energy Converters Based on Historical Data from a Given Point in the Sea

The assessment of wave energy converters is a key issue for planning and managing the economic feasibility wave power plants. However, obtaining reliable assessments is a difficult goal due to the strong stochastic component of wave behaviour. This paper proposes a simple and straightforward assessment method based on empirical data to estimate not only the expected values of converted power, but also their confidence limits. The method combines Gaussian mixed models with the Monte Carlo method. The proposed approach was validated by assessing five converters with data obtained from two different buoys. The daily converted power values agree with the measured wave parameter patterns. Furthermore, all the observed values of monthly generated energy in the three years after the evaluation fell within the forecast intervals, supporting the validity of the proposed approach.

Characterisation of conjugate forced convection in a wavy solar power plant: The role of porous metallic blocks

The current study employs porous metallic blocks to quantitatively explore the characteristics of conjugate heat transport within the wavy solar power plant. Modelling of the flow field within the porous block is done using the Darcy-Brinkman-Forchheimer framework. By employing the boundary conditions, which are consistent with the practical applications, the governing equations are numerically solved for the transport variables. The current work highlights variations in the average Nusselt number, performance factor, temperature field, and conductive heat flux for a window of Reynolds and Darcy numbers. It is anticipated that the intensity of the conductive heat flow will significantly decrease with an increase in Reynolds numbers in its smaller range. The percentage increase in the average Nusselt number when using porous metallic blocks, compared to a porous blockless channel, is estimated to be in the range of 3.3 % to 83.95 % for the examined range of Reynolds numbers. Additionally, the average Nusselt number is underestimated, ranging from 874.17 % to 181.9 %, when considering channels with wall thicknesses half of the channel inlet height within the examined Reynolds number range. As can be shown, the performance factor rises monotonically with the Reynolds number and exceeds unity for increasing Darcy number beyond a critical Reynolds number. Additionally, for lower and higher Reynolds number values, the different influence of wall thickness and its thermal conductivity on performance factor has been predicted. The conclusions drawn from this work seem to be useful for the construction of economical solar plant largely used in many industrial applications as well as for the design of other devices used for effective thermal management of heat.

Induction of tetraploids in Paper Mulberry (Broussonetia papyrifera (L.) L’Hér. ex Vent.) by colchicine

BackgroundBroussonetia papyrifera (L.) L’Hér. ex Vent. has the characteristics of strong stress resistance, high crude protein content, and pruning tolerance. It is an ecological, economic, and medicinal plant. Polyploid plants usually perform better than their corresponding diploid plants in terms of nutrients, active substances, and stress resistance.ResultsIn this study, the leaves, calli, and seeds of diploid B. papyrifera were used for tetraploid induction by colchicine. The induction effect of colchicine on B. papyrifera was summarized through the early morphology, chromosome count and flow cytometry. It was concluded that the best induction effect (18.6%) was obtained when the leaves of B. papyrifera were treated in liquid MS (Murashige and Skoog) medium containing 450 mg·L-1 colchicine for 3 d. The comparative analysis of the growth characteristics of diploid and tetraploid B. papyrifera showed that tetraploid B. papyrifera has larger ground diameter, larger stomata, thicker palisade tissue and thicker sponge tissue than diploid B. papyrifera. In addition, the measurement of photosynthetic features also showed that tetraploids had higher chlorophyll content and higher photosynthetic rates.ConclusionThis study showed that tetraploid B. papyrifera could be obtained by treating leaves, callus and seeds with liquid and solid colchicine, but the induction efficiency was different. Moreover, there were differences in stomata, leaf cell structure and photosynthetic features between tetraploid B. papyrifera and its corresponding diploid. The induced tetraploid B. papyrifera can provide a technical basis and breeding material for the creation of B. papyrifera germplasm resources in the future.

The Effects of Potassium Fertilizer on the Active Constituents and Metabolites of Bulbs from Lilium davidii var. unicolor

Lilium davidii var. unicolor (Lanzhou lily) is rich in nutrients, making it an important economic plant widely used in the fields of food and medicine. In this study, potted lily bulbs were treated with nutrient solutions containing K+ and nutrient solutions without K+ (CK and KT). The contents of nutrients in lily bulbs at different stages after treatment were compared. It was found that the application of potassium fertilizers increased the content of total phenols, flavonoids, and flavanols in lily bulbs and the antioxidant activity in the bulbs. Simultaneously, the study observed that potassium fertilizers could impact the accumulation of polysaccharides and saponins. Furthermore, employing non-targeted metabolomics, the secondary metabolites of mature Lanzhou lily bulbs were scrutinized both with and without potassium fertilization (KT and CK). A total of 607 metabolites were identified, including 573 in positive ion mode and 34 in negative ion mode. These metabolites were classified into 13 categories at the superclass level, with lipids and lipid molecules (37.93%), organic acids and their derivatives (16.52%), organic oxygen compounds (14.88%), and phenylpropanoids and polyketides (13.61%) being the most prominent. Differential metabolite enrichment analysis between the experimental and control groups showed that the differential metabolites were mainly concentrated in metabolic pathways related to amino acid biosynthesis, such as arginine and proline metabolism, beta-alanine metabolism, alanine, aspartate, and glutamate metabolism. Additionally, it was found that the application of potassium fertilizer increased the accumulation of amino acids in Lanzhou lily bulbs. Overall, this study provides a theoretical reference for the development of nutrients and efficient cultivation techniques for L. davidii var. unicolor bulbs.

Genome-wide characterization of tobacco B-BOX gene family identified two close members play contrast roles under cold stress

Cold stress influences the growth and geographical distribution of plants. Tobacco (Nicotiana tabacum L.), a model in plant biology studies and a world-widely cultivated economic plant from tropical America, exhibits extreme sensitivity to low temperatures. The conserved B-BOX (BBX) transcription factors play vital roles in plant photomorphogenesis and flowering regulation, and their functions in abiotic stresses, including cold stress, have been uncovered recently. However, few studies on tobacco BBX genes have been conducted to date. In this study, 49 non-redundant BBX genes have been identified in the reference tobacco genome. Gene structure, phylogenetic relationship, prediction of cis-regulatory elements in promoters, tissue-specific expression patterns, and response to cold stress were conducted on these BBX gene members. The expression of NtBBX9 and NtBBX11, two close members in the amplified group II, was up-regulated under cold treatments. Overexpression of NtBBX11 embedded the cold tolerance of transgenic plants, while the NtBBX9 overexpressors were susceptible to cold. The NtBBX9 functions as a negative regulator of tobacco response to cold stress, which was confirmed by the phenotype of NtBBX9 RNA-silenced lines. Furthermore, we demonstrated that NtBBX9 and NtBBX11 regulated the cold stress response by alternating the expression of critical cold-regulated genes such as CBFs, LEA14, and LTI65 and reactive oxygen species (ROS) production. The combination of NtBBX9 and NtBBX11 could facilitate tobacco’s rapid response to and recovery from transient cold stress and regulate plant cold-responsive growth in tropical regions.

Construction of the core germplasm of yellowhorn (Xanthoceras sorbifolium Bunge) using physiological traits and SSR markers

Yellowhorn (Xanthoceras sorbifolium Bunge) is an important ecological, economic, and ornamental plant species native to China. However, the physiological diversity, genetic variation, and core germplasms have not been revealed, which hindered the breeding process of yellowhorn. Here, we evaluated the genetic diversity of 155 yellowhorn germplasms using five physiological traits. The content of flavonoids varied significantly in different germplasms, and it was positively correlated with soluble sugar content (P < 0.01). A total of 253, 336 candidate SSR were identified from the whole genome of yellowhorn. A moderate genetic diversity was found in yellowhorn based on the mean values of the number of effective alleles (Ne = 2.307), expected heterozygosity (He = 0.527), and observed heterozygosity (Ho = 0.317) with 30 pairs of polymorphic SSR markers. Population structure, Neighbor-Joining phylogeny, and principal coordinates analyses divided all genotypes into two major groups with few admixtures. Meanwhile, we extracted 34 (21.94 %) core yellowhorn germplasms based on the variation in physiological traits (14 germplasms) and genetic diversity (23 germplasms). After multiple different analyses including genetic diversity parameters, coincidence rate of range, variance difference percentage, and coefficient of variation rate of change, there was no obvious difference between core and original germplasm, which indicated that the core germplasm could represent the original germplasm well. Our study will lay a solid foundation for future conservation and management of yellowhorn germplasms and the core collection will be valuable in molecular breeding programs.