Stomatal Characteristics Research Articles

Effects of ploidy level on leaf morphology, stomata, and anatomical structure of Hibiscus syriacus L.

BackgroundHibiscus syriacus L. is a deciduous shrub with a strong environmental resistance and wide application prospects. The genetic background and ploidy levels of Hibiscus cultivars are complex, and polyploid breeding has long been an important method for developing new Hibiscus cultivars. However, the relationship of ploidy levels with leaf morphology, stomatal characteristics, and leaf anatomy remains unclear.ResultsThis study analyzed three ploidy levels (triploid, tetraploid, and hexaploid) of Hibiscus syriacus. Flow cytometry confirmed the ploidy levels, and morphological traits were evaluated. Leaf length, leaf width, and petiole length decreased with increasing ploidy. Stomatal length, stomatal width, guard cell length, and guard cell width increased and stomatal number and density decreased with increasing ploidy. The hexaploids exhibited the highest midrib diameter and palisade tissue thickness values. Correlation analyses revealed that stomatal morphology served as a reliable marker for determining ploidy levels.ConclusionThis study highlights the impact of varying ploidy levels on the leaf and stomatal morphologies and leaf anatomy of Hibiscus syriacus. These findings can provide theoretical guidance for improving Hibiscus cultivars in terms of stress resistance, adaptability, and ornamental traits, and for developing new cultivars with enhanced characteristics. Future research should focus on utilizing these morphological markers to optimize breeding strategies for Hibiscus cultivars.

Comparative analysis of stomatal characteristics and Erysiphe necator (Schw.) Burrill resistance in diverse Vitis sp.

Powdery mildew caused by Erysiphe necator poses a major challenge for grapevine cultivation. This study investigates how stomatal and structural traits influence resistance to this pathogen across diverse Vitis genotypes. Microscopic analysis revealed significant variations in stomatal characteristics. The sunken stomata were observed in V. parviflora, V. jacquemontii, V. rupestris x V. berlandieri (110 Richter) and V. rupestris (St. George) with lower stomatal density. Genotypes with raised stomata had larger stomatal complex areas. Following inoculation with E. necator (accession No. 52218), the Vitis genotypes showed a distinct resistance response. Susceptible V. vinifera genotypes had high pathogen penetration rates, with 71 % of infection attempts forming haustoria. In contrast, V. parviflora, V. jacquemontii, and hybrids such as V. rupestris x V. berlandieri and V. riparia x V. cinerea exhibited programmed cell death (PCD)-mediated resistance, arresting up to 55 per cent of penetration attempts limiting hyphal growth. Cryo-SEM images further indicated sparse fungal growth on the resistant genotypes. The genotype V. parviflora possessed dense trichomes and long wax stripes along the epidermal cells covering leaf veins on the adaxial leaf surface, thus causing a physical barrier against the pathogen. Comparative analyses showed that callose deposition and epicuticular wax significantly contributed to early-stage pathogen defence, while reactive oxygen species and rapid PCD activation triggered hypersensitive responses, enhancing wax deposition and active PCD responses are critical for Vitis sp. resistance to powdery mildew, offering valuable insights for breeding programmes.

Exogenous allyl isothiocyanate mitigates the drought stress by regulating the stomatal characteristic, antioxidant capacity, and glucosinolate metabolism in pakchoi

Drought is a global issue that has increasingly garnered worldwide attention. Glucosinolates (GSLs) are significant sulfur-containing compounds in cruciferous plants such as pakchoi (Brassica rapa L. ssp. chinensis), and their primary biological functions are exerted through their hydrolysis products. Allyl isothiocyanate (AITC), which is one of the degradation products of GSL, plays a crucial role in plants' response to environmental stresses. To date, the drought-resistant mechanism of AITC has not been fully explored. This study investigated the effects of spraying different concentrations of AITC solutions (1 mM and 10 mM) on the growth parameters, stomatal characteristics, antioxidant indices, and glucosinolate metabolism of pakchoi under drought stress, compared to a control group treated with distilled water. The results showed that under drought stress, AITC treatment significantly improved water retention and restored their growth by promoting stomatal closure and improving photosynthetic capacity in pakchoi; mitigated oxidative stress damage and augmenting the plant's water absorption by increasing the activities of antioxidant enzymes and the concentrations of osmoregulatory substances in pakchoi; the application of AITC restored the glucosinolate metabolism in pakchoi, inhibiting the downregulation of genes associated with GSL synthesis and the upregulation of genes related to degradation that is induced by drought stress, thereby maintaining the balance between GSLs and ITCs. In conclusion, AITC application alleviated the inhibition of pakchoi growth under drought stress by fostering stomatal closure, bolstering antioxidant defenses, and modulating glucosinolate metabolism.

Exploring the adaptive mechanisms and strategies of various populations of Sporobolus ioclados in response to arid conditions in Cholistan desert

This study explored the drought resistance mechanisms of different populations of Sporobolus ioclados (Poaceae), locally known as “Sawri,” “Drabhri” and “Dhrbholi” native to Africa and the Indian Subcontinent. These populations were grown in conventional nursery practices at Khawaja Fareed Government College in Rahim Yar Khan, Pakistan, and subsequently subjected to four distinct levels of drought within carefully monitored experimental settings. The experiment was conducted in a two-factorial design involving populations and drought treatments and was repeated three times. The physiological and morphological responses of S. ioclados, including plant height, number of roots, root length, flag leaf area, stomatal features, proline concentration and nitrogen content, displayed significant variability in response to the imposed drought stress. Drought resulted in increases in proline concentration and nitrogen content. The number of roots decreased, while the length and width of the stomata increased in various populations. A combination of advanced statistical techniques, such as ANOVA, PCA, HCA, and DFA, provided a comprehensive understanding of the mechanism of plant adaptation and the extent of population diversity within the species. The Yazman and Nwab Wala populations exhibited the highest rates of photosynthesis and stomatal conductance, while S. ioclados demonstrated notable drought tolerance at the T4 level of drought stress. A negative correlation was found between proline levels, nitrogen contents, and photosynthesis, suggesting that proline has a protective role in drought. The diverse adaptation strategies indicated by S. ioclados populations have revealed the potential of this species for afforestation and climate change mitigation in dry environments.

Vegetation Growth and Physiological Adaptation of Pioneer Plants on Mobile Sand Dunes

The Hunshandake Sandy Land is one of the largest sandy areas in China and the closest source of sand dust to the Beijing and Tianjing areas. Sand fixation by vegetation is considered the most efficient strategy for sand control and sustainable development, so clarifying the vegetation coverage and plant adaptation characteristics in the Hunshandake Sandy Land is helpful in guiding restoration and improving local sustainability. Here, we investigated the vegetation growth on the mobile sand dunes in the Hunshandake Sandy Land and specified the photosynthesis and stomatal characteristics of the pioneer plants for sand fixation. The vegetation survey showed that the windward slopes of the mobile sand dunes had far lower plant coverage (6.3%) and plant biodiversity (two species m−2) than the leeward ones (41.0% and eight species m−2, respectively). Elymus sibiricus L. and Agriophyllum squarrosum (L.) Moq. were the only two sand-fixing pioneer plants that grew on both the windward and leeward slopes of the mobile sand dunes and had higher plant heights, greater abundance, and more biomass than other plants. Physiological measurements revealed that Elymus sibiricus L. and Agriophyllum squarrosum (L.) Moq. also had higher photosynthetic rates, transpiration rates, and water use efficiency. In addition, the stomata density (151–197 number mm−2), length (18–29 μm), and area index (13–19%) of these two pioneer species were smaller than those of the common grassland species in Inner Mongolia, suggesting that they were better adapted to the dry habitat of the mobile sand dunes. These findings not only help in understanding the adaptive strategies of pioneer plants on mobile sand dunes, but also provide practical guidance for sand dune restoration and the sustainable development of local areas. Pioneer sand-fixing plant species that are well adapted to sand dunes can be used for sowing or aerial seeding in sand fixation during ecosystem restoration.

Foliar epidermal micro-morphology of selected brinjal varieties: A study on leaf surface characteristics

Studies on the leaf epidermal morphological characteristics were conducted on the three varieties of brinjal (Solanum melongena L.) belonging to the family Solanaceae. The varieties used in the study were Bhavani Gold, Purple Round and Haritha. Fresh mature brinjal leaves were randomly selected from the three experimental genotypes, and the foliar epidermal features were studied by using light microscopy and SEM imaging. Measurements were taken with an ocular and stage micrometer using 10X and 40X magnifications. The photographs were taken from mounted slides. The stomatal count and each measurement represent the average of ten readings. The upper and lower epidermal surfaces of leaf were studied for stomatal features including, stomatal distribution, stomatal type, stomatal index, stomatal pore length, stomatal pore width, guard cell length, guard cell width, subsidiary cell length and width, epidermal cell type, epidermal cell length and width, trichome type, trichome length and width. Amphistomatous, anisocytic, and with more stomata on the lower epidermal surface than the upper epidermal surface were present in all leaf varieties. On the leaves, the abaxial stomatal index ranged from 68.19 mm-2 (Bhavani Gold) to 56.67 mm-2 (Purple Round) to 58.8 mm-2 (Haritha). While on the adaxial surface, it varied from 59.67 mm-2 (Bhavani Gold), 53.46 mm-2 (Purple Round) and 56.67 mm-2 (Haritha). The three varieties of this study exhibited similarities in the pattern of epidermal cell on the adaxial and abaxial surfaces and were irregular in shape. Among the three varieties epidermal cell become irregular in outline and trichomes were present on both leaf surfaces. It becomes stellate, non-glandular, glandular and 8-12 in number. The highest trichome length was obtained in Bhavani Gold (63 μm) followed by Haritha (57.5 μm) and Purple Round (43 μm) on the upper epidermis. On the lower epidermal region maximum length was obtained in Bhavani Gold (65.5 μm) followed by Haritha (53 μm) and Purple Round (44 μm).

Lack of trichomes and variation in stomata properties influence the quantum efficiency of photosynthesis in Arabidopsis

This study investigates how the absence of trichomes and variations in stomatal properties affect the quantum efficiency of photosynthesis in Arabidopsis thaliana during drought stress. We analyzed three genotypes: Col-8 (with trichomes and lower stomatal density), epf1epf2 (with higher stomatal density), and tmm-1 (lacking trichomes and altered stomatal characteristics) to determine the influence of these anatomical traits on photosynthetic performance. Under well-watered conditions, epf1epf2 and tmm-1 exhibited higher photosynthetic efficiency (Fv´/Fm´) compared to Col-8. During drought stress, Col-8 maintained stable Fv´/Fm´, while epf1epf2 and tmm-1 experienced significant reductions. Our findings indicate that the presence of trichomes and higher stomatal density positively impacts photosynthetic efficiency under optimal watering while the presence of trichomes becomes less crucial under drought stress. Efficient adjustment of stomatal density and size under drought conditions plays a more significant role. These insights emphasize the importance of considering anatomical traits in breeding programs to enhance drought resistance and photosynthetic performance in plants.

Rapid morphological change in UK populations of Impatiens glandulifera

The highly invasive Impatiens glandulifera (Himalayan balsam) is one of the most prolific and widespread invasive plants in the British Isles. Introduced in the early nineteenth century, it has now been reported in almost every vice county across the UK and is a fierce competitor that has adverse effects on the local community structure. Despite the negative impacts that invaders like I. glandulifera have on local communities, there have been very few studies which address the morphological changes that invasive plant populations have undergone since their initial introduction. This is the first study of its kind to investigate the morphological changes that have occurred in I. glandulifera. 315 herbarium specimens dating from 1865 to 2017 were used to measure changes in morphological traits such as leaf size, flower length and stomatal characteristics. We found that since 1865, there has been a significant reduction in overall leaf size, a significant reduction in stomatal density and a significant increase in the overall flower length. These results highlight the importance of monitoring the evolutionary change in prolific alien species over the course of their invasion, providing useful insights into changes in competitive ability which may prove useful in managing dispersal and providing options for potential management.

Decoding stomatal characteristics regulating water use efficiency at leaf and plant scales in rice genotypes.

Stomatal traits in rice genotypes affect water use efficiency. Low-frequency small-size stomata correlate with whole plant efficiency, while low-frequency large-size stomata show intrinsic efficiency and responsiveness to vapour pressure deficit. Leaf surface and the patterning of the epidermal layer play a vital role in determining plant growth. While the surface helps in determining radiation interception, epidermal pattern of stomatal factors strongly regulate gas exchange and water use efficiency (WUE). This study focuses on identifying distinct stomatal traits among rice genotypes to comprehend their influence on WUE. Stomatal frequency ranged from 353 to 687 per mm2 and the size varied between 128.31 and 339.01 μm2 among 150 rice germplasm with significant variability in abaxial and adaxial surfaces. The cumulative water transpired and WUE determined at the outdoor phenomics platform, over the entire crop growth period as well as during specific hours of a 24h-day did not correlate with stomatal frequency nor size. However, genotypes with low-frequency and large-size stomata recorded higher intrinsic water use efficiency (67.04μmol CO2 mol-1 H2O) and showed a quicker response to varying vapour pressure deficit that diurnally ranged between 0.03 and 2.17kPa. The study demonstrated the role of stomatal factors in determining physiological subcomponents of WUE both at single leaf and whole plant levels. Differential expression patterns of stomatal regulatory genes among the contrasting groups explained variations in the epidermal patterning. Increased expression of ERECTA, TMM and YODA genes appear to contribute to decreased stomatal frequency in low stomatal frequency genotypes. These findings underscore the significance of stomatal traits in breeding programs and strongly support the importance of these genes that govern variability in stomatal architecture in future crop improvement programs.

Understanding mechanistic variability in physiological and biochemical responses of pea cultivars (Pisum sativum L.) to ozone exposure

Increasing concentration of ground level O3 and its negative impacts on agricultural output is well documented, however, the response of leguminous crop plants is still sparsely cited. Given their nutritional richness, legume seeds are widely esteemed as a crucial dietary staple worldwide, prized for their abundance of oil, protein, dietary fiber, and low-fat characteristics. Termed as the “poor man's meat” due to their high-quality protein, they hold immense economic value. Acknowledging the significance of legumes, a field experiment was conducted to understand the physiological and antioxidant responses, stomatal characteristics, and yield response in three cultivars of Pisum sativum L. (K Agaiti, K Uday and K Damini), exposed to elevated ozone (O3). In the present study, Pisum sativum cultivars were subjected to ambient (control) and elevated (+15 ppb) concentrations of O3, using separate sets of OTCs. Elevated O3 stimulated the activity of the enzymes of Halliwell Asada pathway, which were responsible for the differential response of the three experimental cultivars. While K Agaiti and K Uday focused on upregulating their antioxidant defense, K Damini followed the strategy of biomass allocation. Test weight showed that K Damini was most efficient in succoring the yield losses under elevated O3. Under elevated O3, test weight reduced by 8.91%, 7.52%, and 5.1%, respectively, in K Agaiti, followed by K Uday and K Damini, rendering K Agaiti most sensitive to O3 stress. The present study not only helps us to elucidate the O3 sensitivity of the selected experimental cultivars, it also helps us in screening O3 tolerant cultivars for future agricultural practices.

PHYSIO-ANATOMICAL EVALUATION OF SOME TREE SPECIES FOR AFFORESTATION IN DRY REGION OF KOGI STATE, NIGERIA

The stomatal features of plant species have ability to release water vapour into the air. Hence, correlations between the stomatal features and transpiration rate of five tree species namely Danielli oliveri, Delonix regia, Piliostigma thonningii, Azadirachta indica and Tectona grandis was studied to evaluate their capacity for afforestation. The leaf epidermal layers were isolated using nail polish; they were observed under the light microscope to examine their stomatal features. The transpiratiom rate was evaluated using the cobalt chloride method. The results revealed that Delonix regia and Piliostigma thonningii are amphistomatic; while the remaining three species are hypostomatic. The stomatal complex types observed are anomocytic, brachyparacytic and paracytic, The stomatal density ranged from 14.41 mm-2 to 93.61 mm-2; the stomatal index ranged from 7.15% to 28.23%; while the stomatal size ranged from 11.19 µm2 to 29.36 µm2. The study revealed that stomatal traits such as hypostomatic leaf nature, stomatal complex types (i.e. paracytic, brachyparacytic), low stomatal index, small stomatal size possessed by the plant species may be responsible for their lower rate of transpiration; which in turn might be suitable for their afforestation in dry areas. Therefore, Tectona grandis which released the lowest amount of water (2.49 × 10-6 mol m-2s-1) into the atmosphere might be the most suitable for afforestation, followed by Piliostigma thonningii, Daniellia oliveri, Delonix regia and lastly Azadirachta indica (2.97 × 10-6 mol. m-2s-1). Conclusively, the stomatal features showed positive correlations with transpiration rates; thereby enhancing the potentials of the studied species for afforestation in dry region.

Analysis of Intra- Cultivar Heterogeneity in Dashehari Mango (Mangifera Indica L.) by Using Scanning Electron Microscopy

The present study aimed at estimating intra-cultivar heterogeneity in Dashehari cultivar of mango (Mangifera indica L.) by using Scanning Electron Microscopy (SEM). Forty-five trees of 25-30 years old, from 15 orchards in Malihabad and Mall blocks of district Lucknow, Uttar Pradesh were selected for study which revealed a significant variation in all stomatal characteristics. Phenotypic and Genotypic coefficient of variation (PCV and GCV, respectively) values for these parameters were very close, indicating that they were controlled at genetic level and were independent of environmental effect. Highest phenotypic (41.59) and genotypic (38.27) coefficient of variation, and Genetic advance as percent of mean (GAM) (149.41 %) were recorded for stomatal pore size (width) while highest (97.50) heritability (h2) and genetic advance (20.86) were observed for stomatal density. Dendrogram clusters of the Dashehari population under study, prepared based on stomatal observations, divided into two main clusters which further divided into sub-clusters. The study on stomatal characters is fully facilitated by SEM and hence, it is suggested that SEM may be a useful tool for identification of intra-varietal variability of Dashehari mango for further crop improvement programme. Bangladesh J. Bot. 53(2): 391-399, 2024 (June)

Selenium Nanoparticles Boost the Drought Stress Response of Soybean by Enhancing Pigment Accumulation, Oxidative Stress Management and Ultrastructural Integrity

Drought is a persistent and devastating obstacle to crop production, affecting both humanity and livestock. The application of selenium (Se) effectively mitigates various types of abiotic stresses and enhances crop yield under unfavorable conditions. However, our understanding of how nano-Se (nSe) alleviates drought stress (DS) in soybeans is still limited. To address this gap, our study focused on assessing the effectiveness of foliar nSe application during the reproductive stage of soybeans. Three concentrations of nSe were applied to plants grown in pots filled with clay loam soil, simulating DS conditions. Our findings reveal that nSe spraying significantly promoted the accumulation of above-ground dry biomass and enhanced relative water content (RWC) and photosynthetic pigment over alone-DS treatment. Furthermore, nSe application boosted the activity and contents of protective enzymes and osmolytes, resulting in a dose-dependent reduction in electrolyte leakage (EL), reactive oxygen species (ROS) accumulation, and malondialdehyde (MDA) content. Additionally, nSe improved stomatal characteristics and mesophyll cell ultrastructure, further mitigating the adverse effects of drought stress. These findings suggest the potential of nSe as an effective strategy to enhance soybean tolerance and potentially improve crop yields under drought conditions.

Reponses of morphological and biochemical traits of bamboo trees under elevated atmospheric O3 enrichment

Dwarf bamboo (Indocalamus decorus) is an O3-tolerant plant species. To identify the possible mechanism and response of leaf morphological, antioxidant, and anatomical characteristics to elevated atmospheric O3 (EO3) concentrations, we exposed three-year-old I. decorus seedlings to three O3 levels (low O3-LO: ambient air; medium O3-MO: Ambient air+70 ppb high O3–HO: Ambient air+140 ppb O3) over a growing season using open-top chambers. Leaf shape and stomatal characteristics, and leaf microscopic structure of I. decorus were examined. The results indicated that 1) the stomata O3 flux (Fst) of HO decreased more rapidly under EO3 as the exposure time increased. The foliar O3 injury of HO and MO occurred when AOT40 was 26.62 ppm h and 33.20 ppm h, respectively, 2) under EO3, leaf number, leaf mass per area, leaf area, and stomata length/width all decreased, while leaf thickness, stomatal density, width, and area increased compared to the control, 3) MDA and total soluble protein contents all showed significantly increase under HO (36.57% and 32.77%) and MO(31.91% and 19.52%) while proline contents only increased under HO(33.27%). 4) MO and HO increased bulliform cells numbers in the leaves by 6.28% and 23.01%, respectively. HO reduced the transverse area of bulliform cells by 13.73%, while MO treatments had no effect, and 5) the number of fusoid cells interspace, the transverse area of fusoid cells interspace, and mesophyll thickness of HO significantly increased by 11.16%, 28.58%, and 13.42%, respectively. In conclusion, I. decorus exhibits strong O3 tolerance characteristics, which stem from adaptions in the leaf's morphological, structural, antioxidant, and anatomical features. One critical attribute was the enlargement of the bulliform cell transverse area and the transverse area of fusoid cells interspace that drove this resistance to O3. Local bamboo species with high resistance to O3 pollution thus need to be promoted for sustained productivity and ecosystem services in areas with high O3 pollution.

A Comparative Study Of Stomatal Characteristics of The Nine Pandanus Species From Nias Island, North Sumatra Province, Indonesia

AbstractThe identification of Pandanus species generally relies on morphological characteristics and requires confirmation from other identification features, such as stomata. A comparative study of stomatal characteristics among nine Pandan species originally from Nias Island, namely Pandanus atrocarpus, P. auranticus, P. labyrinthicus, P. militaris, P. odoratissimus, P. penangensis, P. tectorius, and P. utilis has been investigated. Anomocytic stomata without papillae on subsidiary cells were observed on both leaf surfaces, with significant interspecific differences in adaxial and abaxial stomatal frequencies. Pandanus tectorius exhibited the highest adaxial (30.71 ± 0.81) and abaxial (1.87 ± 0.12) stomatal frequencies. Pandanus labyrinthicus showed the highest stomatal index (adaxial 16.61 ± 2.51, abaxial 0.87 ± 0.11), while P. penangensis had the largest stomatal size (137.54 ± 6.66 µm). Overall, the stomatal parameters, including frequency, index, and size, were higher on the adaxial surface than the abaxial surface, emphasizing interspecific variations. These findings contribute valuable supportive data for the botanical systematics of Pandanus spp. in the region, enhancing our understanding of morphological characteristics crucial for species identification.AbstrakIdentifikasi jenis dari Pandanus cenderung menggunakan ciri morfologi dan memerlukan konfirmasi dari karakter lainnya, salah satunya stomata. Studi perbandingan stomata di antara sembilan spesies Pandan di Pulau Nias, Sumatera Utara telah dilakukan, yaitu Pandanus atrocarpus, P. auranticus, P. labirinthicus, P. militaris, P. odoratissimus, P. penangensis, P. tectorius, dan P. utilis. Hasil penelitian menunjukkan bahwa keseluruhan jenis Pandanus memiliki tipe stomata berupa anomositik pada kedua permukaan daun atau amfistomatous tanpa adanya papilosa pada sel tambahan. Frekuensi stomata adaksial dan abaksial memiliki perbedaan yang nyata secara statistik lintas jenis. Frekuensi stomata tertinggi pada daun adaksial/abaksial diamati berturut-turut dari P. tectorius (30,71 ± 0,81) dan P. tectorius (1,87 ± 0,12). Indeks stomata daun tertinggi diamati berturut-turut berasal dari P. labirinthicus (16,61 ± 2,51) untuk adaxial dan P. labirinthicus (0,87 ± 0,11) untuk abaxial. Ukuran stomata terbesar diamati berturut-turut berasal dari P. penangensis (137,54 ± 6,66 µm) dan P. odoratissimus (64,56 ± 3,96 µm). Secara umum, tipe stomata pada semua jenis adalah anomositik tanpa adanya papila pada sel penjaga. Parameter stomata lainnya, yaitu frekuensi, indeks, dan ukuran pada bagian adaksial cenderung lebih tinggi dibandingkan permukaan abaksial dengan variasi nilai secara interspesifik.

Assessment of Hexaconazole Fungicide's Impact on Root Growth and Stomatal Characteristics of Allium cepa L.

Assessment of Hexaconazole Fungicide's Impact on Root Growth and Stomatal Characteristics of Allium cepa L.

Intergenerational priming by Trichoderma alleviates drought stress in barley

The escalating global climate anomalies and disruption of ecological equilibrium pose profound threats to agroecosystems and crop productivity. Drought stress, a prominent consequence of climate change, exert detrimental effects on plant physiology, thereby reducing crop yield. This study explores the implementation of Trichoderma-mediated defence priming in barley under drought stress. Through a comprehensive evaluation of encompassing morphological, stomatal, biochemical, and yield parameters, Trichoderma- primed barley is compared with non-primed barley under drought stress conditions. Our results revealed that Trichoderma-primed barley exhibits heightened tolerance to drought stress in comparison to non-primed barley. The improved stomatal characteristics indicate that Trichoderma priming enables the plant to better adapt to drought conditions. Biochemical analysis showed enhanced photosynthetic pigments and reduced MDA in primed barley under drought, suggesting that primed barley experiences less oxidative stress compared to non-primed barley. Additionally, Trichoderma-primed plants displayed heightened levels of both non-enzymatic and enzymatic antioxidant activities, aiding in ROS detoxification. Stress responses are activated upon encountering a triggering stimulus (drought stress), but not after Trichoderma priming. This means there was no wasteful diversion of resources towards resistance mechanisms in the absence of stressful situations, leading to enhanced yield for primed barley compared to non-primed barley under stressful conditions. Furthermore, our investigation into the heritability of priming effects in the succeeding generation demonstrates that the progeny of primed barley retains enhanced protection akin to their primed parents. In contrast the progeny of non-primed barley exhibits greater vulnerability under water-deficit conditions. The expression of the epigenetic regulator gene HvDME was more enhanced in primed barley and its subsequent generations than in non-primed barley. This research emphasizes the potential of Trichoderma priming as a cost-effective strategy to enhance barley production amidst climate change challenges. The priming defense approach offers an intelligent plant health management solution devoid of adverse environmental or yield-related implications. This discovery holds significant promise, particularly in regions with limited water resources where crops are highly susceptible to drought stress. The findings contribute to the advancement of sustainable and climate-resilient agriculture, offering insights for practitioners and policymakers aiming to address the adverse impacts of climate change on crop production.

Performance of Convergent Breeding Wheat (Triticum aestivum L.) Lines in the Lowlands

The development of tropical wheat in Indonesia is currently confined to the availability of wheat’s optimal environments in the highlands. Wheat competes with major highland crops, such as vegetables, which also have high economic values. Despite this, the demand for wheat in Indonesia remains high, whether in the form of wheat flour, wheat meal, or oats. Wheat breeders are actively working to create various crossbreeds so that wheat can adapt and perform effectively in lowland areas. The convergent breeding method is one of the strategies employed to produce genotypes with superior performance. Convergent breeding enhances genetic diversity by incorporating superior traits from all parent plants. The breeding results expedite the emergence of genetic combinations between selected parents. This method involves combining several parent varieties with various traits, with the hope that their offspring will inherit all the characteristics of the crossed parents. Our study with wheat convergent breeding has reached the F6 generation, and in this current study we evaluated the performance of each observed trait in different environments, with the goal of determining the levels of homogeneity and homozygosity. The study utilized a randomized complete block design with three replications, and the crops were planted in various locations. The planting locations selected were those that are >1000 m above sea level (asl), and at a lowland of ± 250 m asl. Wheat performance based on stomatal characteristics showed a reduction in the lowland, which indicates a response to climatic conditions in a particular environment. The higher the environmental temperatures, the smaller the stomatal size, which reduces plant water loss. Noteworthy findings include the tallest plant in CBF-6. CAMN23(265), the highest number of tillers in CBF-6. CAMN233 and CBF-6.CAMN8(4), the largest flag leaf area in CBF-7.CAMN60, and the highest 100-seed weight, as well as overall yield in CBF-7.CAMN119. An analysis of the lowland sensitivity index identified ten moderate genotypes that could potentially adapt well and achieve optimal yields.

Determining Formaldehyde Phytoremediation Efficacy of Selected Ornamental Plants

In the recent past, deterioration of indoor air quality has become a serious concern due to the increased energy efficiency and reduced air exchange rate inside urban buildings. Volatile organic compounds (VOCs) are a major category of indoor air pollutants that can lead to adverse health outcomes such as headaches, allergies and asthma in those exposed for prolonged periods. Formaldehyde, the VOC used in the present study is a common contaminant of indoor air which originates from particle board, plywood, paper products, certain adhesives, tobacco smoke and other sources. The use of plants for the mitigation of indoor air pollution is viewed as a cost effective and eco-friendly method with untapped potential. The main objective of the present study was to determine the formaldehyde removal efficacy of selected plant species while investigating the mechanisms used by these plants in the removal process. The selected plant species were Zamioculcas zamiifolia, Hedera helix, Dracaena sanderiana and Ficus sp. Plants of the same age were used with three replicates from each species. Phytoremediation potential was assessed by exposing the plants for 24 hours to gaseous formaldehyde (2.0 μL L-1) in air tight chambers made of Plexiglass (an inert material for VOCs) with dimensions of 0.9 m height×0.58 m length×0.55 m width. Formaldehyde removal was measured using GC-MS and the result was expressed as removal percentages. Several leaf anatomical characters (cuticle thickness, epidermal thickness and mesophyll layer thickness), stomatal characters (stomatal density, stomatal index, guard cell length and potential conductance index) and physiological characters (stomatal conductance and photosynthetic rate) were measured to study the possible mechanisms involved in the formaldehyde removal process. The data were subjected to ANOVA and Pearson correlation test. According to the results obtained, Ficus sp. had the highest formaldehyde removal percentage (92.80%) while Hedera helix had the lowest (56.86%). The study further showed that stomatal density and stomatal conductance play a major role in formaldehyde removal by these plants while cuticle and epidermal thickness act as hindrances to this process. This conclusion was further confirmed by Pearson‘s correlation values in correlation analysis. The current study was carried out for 24 hours of exposure and it would be of interest to explore, the long term behavior of the plants through further studies. Overall, the results justify future studies on a cross-section of diverse plant species for formaldehyde removal efficiency to determine species with superior removal efficiencies for a better phytoremediation process. 
 Keywords: Phytoremediation, VOCs, Formaldehyde, GC-MS technology

Seasonal variation of stomatal characteristics of Ficus species grown in Zaria, North Western Nigeria

Foliar stomatal characteristics are among the commonly used characters for the identificationand delimitation of taxa. This study was carried out to determine variations in stomatalcharacteristics of some members in the Genus Ficus grown in Zaria, part of the Sudan Savanna zone of Nigeria. Eight different Ficus species grown in Zaria were used for the study. Microscopic observations of foliar stomatal characteristics were carried out following standard established protocols during both the dry and rainy seasons. Stomatal preparations were obtained using matured leaves by treating each leaf with sodium hypochlorite to clear the chlorophyll contents. Measurements of stomatal characters were made with the aid of an ocular micrometer and stage micrometer. Photomicrographs were taken. The data obtainedwere subjected to analysis of variance (ANOVA) with Duncan’s New Multiple Range Test used to separate significant means at 5 % level. The result obtained revealed significant difference (P≤0.05) in the stomatal characteristics of the Ficus species with season. Anomocytic stomata was detected in all the species. There were variations with abaxial stomata cell length ranging from 23.32-50.24 μm in dry season and in the rainy season, the abaxial cell length ranged between 26.78-46.43 μm. Also, the stomatal index in the dry season ranged from 1.30% to 27.16% while in the rainy season, it ranged from 15.29 % to 23.19 %.