Reduction In Dry Weight Research Articles

Genome-Wide Identification and Functional Validation of Actin Depolymerizing Factor (ADF) Gene Family in Gossypium hirsutum L.

The Actin Depolymerizing Factor (ADF) protein, highly conserved among eukaryotes, is essential for plant growth, development, and stress responses. Cotton, a vital economic crop with applications spanning oilseed, textiles, and military sectors, has seen a limited exploration of its ADF gene family. This research has identified 118 unique ADF sequences across four principal cotton species: Gossypium hirsutum L., Gossypium barbadense Linn, Gossypium raimondii, and Asiatic cotton. The study found that the structural domains and physicochemical properties of these proteins are largely uniform across species. The ADF genes were classified into four subfamilies with a notable expansion in groups III and IV due to tandem and chromosomal duplication events. A thorough analysis revealed a high degree of conservation in gene structure, including exon counts and the lengths of introns and exons, with the majority of genes containing three exons, aligning with the characteristics of the ADF family. RNA-seq analysis uncovered a spectrum of responses by GhADFs to various abiotic stresses with GhADF19 showing the most significant reaction. Virus-induced gene silencing (VIGS) experiments were conducted to assess the role of GhADF19 in plant growth under abiotic stress. The results demonstrated that plants with silenced GhADF19 exhibited significantly slower growth rates and lower dry weights when subjected to cold, salt, and drought stress compared to the control group. This marked reduction in growth and dry weight under stress conditions highlights the potential importance of GhADF19 in stress tolerance mechanisms.

Effects of cowpea aphid-borne mosaic virus infection on the growth and yield parameters of Sesamum indicum plants

The potyvirus cowpea aphid-borne mosaic virus (CABMV) is the main viral agent present in crops of Sesamum indicum in several regions of Paraguay. However, information about the effects of CABMV infection in S. indicum plants is scarce and the critical period for virus infection in S. indicum plants is unknown. This study aimed to evaluate the damage caused by CABMV on the development and yield of S. indicum plants experimentally infected at three phenological stages. Mechanical inoculations of CABMV were performed on S. indicum plants at the early vegetative stage, at the beginning of flowering, and during capsule and seed formation. An enzyme-linked immunosorbent Assay (ELISA) test was used to confirm virus infection on the inoculated plants using specific CABMV antisera. Plants inoculated 30 days after emergence (DAE) had severe systemic symptoms, but they were mild in mid and late-infected plants (60 and 90 DAE). Plant aerial dry weight was significantly affected by CABMV infection, reducing up to 71.6% compared to the control. Mid and late-infected plants experienced a lower level of damage, with an average aerial dry weight reduction of 17 and 14.2%, respectively. Furthermore, plants with early, mid, and late CABMV infections showed an average capsule per plant reduction of 97, 33.3, and 13.3%, compared to healthy plants. Seeds per capsule produced by CABMV-infected plants decreased by 93.5%, 21%, and zero, respectively. Viral infections also affected the 1000-seed weight in early infected plants, with a reduction of up to 93.3%. To prevent economic losses, it is crucial to have effective strategies for managing CABMV, particularly during the early stages of the crop.

Cover crop and herbicides can control purple nutsedge (Cyperus rotundus L.) and increase crop yields in conservation agriculture-based crop rotations

Adoption of conservation agriculture (CA) practices can lead to the dominance of perennial weeds including purple nutsedge (Cyperus rotundus L.) in different agroecologies over time. Without effective management of this weed, successful adoption of CA in smallholder farming systems is rather unlikely. Therefore, we aimed to develop an integrated strategy for managing C. rotundus in CA-based crop rotations. This study encompassed a two-year (during 2020–21 and 2021–22) field experimentation at Kanpur, India with a split-plot design with three replications. The treatments included purple nutsedge management practices in main plot and crop rotations in sub-plot under CA platform (no-tilled with added crop residues). Six management options were adopted in the summer season (during April to June) as main plots that were super-imposed with two crop rotations such as pigeonpea (Cajanus cajan (L.) Huth) – wheat (Triticum aestivum L.) and pearlmillet (Pennisetum glaucum (L.) R.Br) – chickpea (Cicer arietinum L.) as sub-plot. Growing of cover crop Sesbania (Sesbania aculeata (Willd.) Pers.) during the summer season for 45 days followed by knockdown with 2,4-D 500 g a.i. Ha−1 (cultural management; Sesbania+2,4-D) and/or summer irrigation followed by application of halosulfuron-methyl 70 g a.i. Ha−1 at 20 days after irrigation (chemical management; halosulfuron-methyl) reduced the C. rotundus density by 37–42% and 23–64% over years, respectively, than conventional practice (ploughing during summer followed by irrigation and glyphosate 1.5 kg a.e. Ha−1 application). Besides, these practices could decrease 25–27% total weed density (p < 0.05) than conventional practice (mean of years) in summer season. Importantly, these management practices had a carry-over effect on reduction in density of C. rotundus and total weeds of rainy and winter season crops. For instance, Sesbania +2,4-D and halosulfuron-methyl decreased 35% and 15% density of C. rotundus, respectively, during rainy season than conventional practice. Irrespective of crop rotations, Sesbania +2,4-D and halosulfuron-methyl decreased 30–40% density of C. rotundus (mean of years) in winter season than conventional practice (p < 0.05). A significant reduction in dry weight of C. rotundus was recorded under Sesbania +2,4-D and halosulfuron-methyl in summer season by 13–23%, rainy season by 23–29%, and winter season by 55–72% than conventional practice. Pearlmillet-chickpea rotation had a 10–35% lower infestation of C. rotundus than pigeonpea-wheat (p < 0.05). Management practices such as Sesbania +2,4-D and halosulfuron-methyl had higher system productivity by 15–19% in 2020–21 (p < 0.05), 5–7% in 2021–22 (p > 0.05), and 10–12% in average (p > 0.05) than conventional practice. Summer mungbean cultivation increased 45.2% and 10.1% density of C. rotundus in rainy season over Sesbania +2,4-D and halosulfuron-methyl in CA system, respectively (p < 0.05). Furthermore, the density of this weed was significantly higher under pigeonpea crop during rainy season by 41.4% than under pearlmillet crop (mean of years). Therefore, system-based approaches such as growing of cover crop Sesbania followed by knockdown with 2,4-D (Sesbania +2,4-D) and/or herbicide-based management through halosulfuron-methyl during summer season and subsequently recommended weed management practices in cropping systems (pearlmillet – chickpea and pigeonpea – wheat) can reduce the infestation of C. rotundus and total weeds in CA than conventional practice.

Enhancing salinity stress tolerance in corn salad (Valerianella locusta L.) through melatonin or salicylic acid-functionalized chitosan seed priming: A smart delivery approach

Soil salinity represents a significant environmental stressor that impairs crop production and yield. A wide range of treatments have been used to reduce the effects of salinity in plants. Among the treatments used, functionalized nanoparticles (NPs) have shown great results. In light of recently demonstrated beneficial effects of chitosan-melatonin nanoparticles (CTS-Mel NPs) and chitosan-salicylic acid nanoparticles (CTS-SA NPs) in mitigating the deleterious consequences of major stress factors and boosting secondary metabolite biosynthesis, the current study aimed to investigate their potential as seed priming coatings to enhance plant performance under both control and salinity stress conditions. For this purpose, CTS (0.1% w/v), Mel (50 µM), SA (0.5 mM), CTS-Mel NPs and CTS-SA NPs were applied as seed priming agents on corn salad (Valerianella locusta) seeds, and subsequently key morphophysiological and biochemical properties were assayed under salinity conditions (0, 30 and 60 mM NaCl). Accordingly, salinity stress caused significant reduction in fresh and dry weights (FW and DW) of leaves, chl a, total chl, SPAD and enhancement in content of proline, phenolics, MDA, as well as protein content, and activities of SOD and CAT antioxidant enzymes. Concerning the phenolic compounds analyzed, salinity stress did not affect the dominant phenolic constituents with the exception of naringine. Regarding the protective effects of the various priming treatments, the adverse effects of salinity stress were ameliorated with the application of most of the applied treatments, and with CTS-Mel NPs in particular, by enhancing biomass, pigments, total phenols, protein, SOD and CAT antioxidant enzymatic activities, as well as the content of some dominant constituents of phenolic profile. CTS-Mel NPs enhanced chlorogenic acid, naringine, o-coumaric acid and catechin hydrate under both control and salinity conditions. Overall, CTS-Mel NPs outperformed CTS-SA NPs as a seed priming coating and could potentially be widely introduced as an innovative, sustainable approach to mitigate the effects of salinity and other abiotic stress conditions in crop plants.

Advanced Dehydration Techniques Standardized for Flowers of Gomphrena globosa L.

The present experiment was conducted on standardizing dehydration technique for Gomphrena globose flower by using embedding drying methods in room temperature and hot air oven at 55°C was done. The experiment consisted of 10 treatments with 3 replications designed in completely randomized design. Treatments used were as; T1-Boric acid (room temperature), T2-Silica gel (room temperature), T3-Sand (room temperature), T4-Sawdust (room temperature), T5-Cocopeat (room temperature), T6-Boric acid (hot air oven at 55 °C), T7-Silica gel (hot air oven at 55 °C), T8-Sand (hot air oven at 55 °C), T9-Sawdust (hot air oven at 55 °C), T10-Cocopeat (hot air oven at 55 °C). The most reduction in flower fresh and dry weight, measuring 2.36 and 2.12 g, was observed in Treatment T7 (Silica gel with hot air oven at 55°C), where silica gel was employed as the desiccant. The least reduction in flower fresh and dry diameter, measuring 1.92 and 1.81 g, was observed in Treatment T7 (Silica gel with hot air oven at 55°C), where silica gel was employed as the desiccant. The highest drying duration for gomphrena in T3 (Sand) and T4 (Sawdust) treatments was 234.21 and 210.40 hrs at room temperature. The boric acid and silica gel demonstrated outstanding performance in terms of quality parameters, including texture, color, and overall appearance. Among all treatment, embedding drying with silica with hot air oven dehydration at 55°C was found to be best in term of reduction in weight, diameter and overall colour, appearance and texture of Gomphrena globose flowers.

Selenium improved arsenic toxicity tolerance in two bell pepper (Capsicum annuum L.) varieties by modulating growth, ion uptake, photosynthesis, and antioxidant profile

Bell pepper (Capsicum annuum L.); an important spice crop of the region is a rich source of vitamins and antioxidants having many health benefits. Many biotic and abiotic factors contribute towards growth and yield losses of this crop. Arsenic (As) toxicity is a global issue, but it is particularly critical in developing countries. The current study was designed to evaluate the efficacy of selenium (Se) in mitigating the toxic effects of As in two varieties (HSP-181 A and PS09979325) of Capsicum annuum L. Different concentrations of As (0, 50, and 100 µM) and Se (0, 5, and 10 µM) were tested using 14 days old seedlings of C. annuum L. The As stress caused a significant (P ≤ 0.001) reduction in growth, uptake of nutrients, and eco-physiological attributes in both varieties however, the response was specific. While the overproduction of osmo-protectants and antioxidants intensified the symptoms of oxidative stress. The maximum reduction in shoot length (45%), fresh weight (29%), and dry weight (36%) was observed in under 100 µM As stress. The organic acids exudation from the roots of both cultivars were significantly increased with the increase in As toxicity. The Se treatment significantly (p ≤ 0.001) improved growth, nutrient uptake, gas exchange attributes, antioxidant production, while decreased oxidative stress indicators, and As uptake in the roots and shoots of all the subjects under investigation. It is concluded from the results of this study that Se application increased photosynthetic efficiency and antioxidant activity while decreasing As levels, organic acid exudation, and oxidative stress indicators in plants. Overall, the var. PS09979325 performed better and may be a good candidate for future pepper breeding program.

Effects of Plant Growth-promoting Microorganisms on the Early Growth of Kentucky Bluegrass under Drought and Salinity

Drought and salinity affect turfgrass growth and development adversely. Plant growth-promoting microorganisms (PGPMs) have been shown to have the capability of improving resistance to biotic stressors in plants. The objective of this research was to determine the efficacy of six commercial PGPMs on enhancing the drought and salinity resistance of kentucky bluegrass (Poa pratensis). The six PGPMs evaluated were Beauveria bassiana (strain GHA), Bacillus subtilis (strain GB03), Azadirachtin, Bacillus firmus (strain 1-582), Trichoderma harzianum Rifai (strain T-22) combined with Trichoderma virens (strain G-41), and Bacillus subtilis (strain QST713). Three cultivars—Kenblue, Moonlight, and Waterworks—were seeded in the greenhouse. Two-week seedlings were exposed to saline (sodium chloride at 6 dS⋅m–1 three times per week) or drought (tap water once per week) conditions, and no stress (irrigated with tap water three times per week) for 4 weeks. Results show that drought and salinity inhibited turf growth, with the greatest reduction in root dry weight (50.3% in drought conditions and 31.4% in saline conditions). ‘Kenblue’ performed better than ‘Waterworks’ and ‘Moonlight’ in all growth indices except for root length. Beauveria bassiana and B. subtilis had a similar or better result in enhancing turfgrass growth and development compared with the untreated turf under stress. Our results suggest that certain PGPMs have the potential to improve abiotic stress resistance in turfgrass.

Inhibition of Pre-Emergent Herbicide on Weedy Rice under Flooded and Saturated Soil Conditions in Rice

Weedy rice poses a formidable challenge in rice cultivation due to its genetic similarity to cultivated rice, making selective herbicides less effective in controlling it without causing harm to the cultivated rice. The potential use of pre-emergent herbicides before rice sowing to inhibit emergence and growth of weedy rice seedlings in the soil remain unknown. Thus, this study aimed to evaluate the responses of weedy rice towards selected pre-emergent herbicides under different soil water conditions and to identify the optimal timing for rice seed sowing following the application of pre-emergent herbicide to the soil under glasshouse conditions. The results showed that oxadiazon and pretilachlor at 500 g ai ha-1 exhibited higher reductions in weedy rice density and dry weight compared to those given by pendimethalin. Under saturated soil conditions, oxadiazon demonstrated 79 and 80% reductions whereas pretilachlor gave 50 and 59% reductions in weedy rice density and dry weight, respectively. By contrast, under flooded soil conditions both oxadiazon and pretilachlor resulted in complete inhibition of weedy rice. The study showed that delaying rice seed sowing for at least six days after application of pretilachlor or oxadiazon effectively minimized phytotoxic effects on rice. These findings provide valuable insights on the impact of soil water conditions when applying pretilachlor and oxadiazon for effective weedy rice control in direct-seeded rice systems.

Potassium silica nanostructure improved growth and nutrient uptake of sorghum plants subjected to drought stress.

Recent advancements in nanotechnology present promising opportunities for enhancing crop resilience in adverse environmental conditions. In this study, we conducted a factorial experiment to investigate the influence of potassium nanosilicate (PNS) on sorghum plants exposed to varying degrees of drought stress A randomized complete block design with three replications was employed to subject the sorghum plants to different drought conditions. The three levels of stress were designated as non-stress (NS at -0.03 MPa), moderate stress (MD at -0.6 MPa), and severe stress (SD at -1.2 MPa). The plants were administered PNS at concentrations of 0 mM (control), 3.6 mM Si, and 7.2 mM Si. As drought stress intensified, we observed significant reductions in multiple plant parameters, including height, fresh weight, dry weight, leaf number, stem diameter, cluster length, seed weight, and nutrient uptake, with the most pronounced effects observed under SD conditions. Interestingly, nitrogen (N) and potassium (K) levels exhibited an increase under drought stress and PNS application, peaking at MD, alongside Si concentrations. Notably, PNS application facilitated enhanced nutrient uptake, particularly evident in the significant increase in nitrogen concentration observed at 3.6 mM PNS. Furthermore, the application of PNS significantly enhanced the fresh weight and nutrient concentrations (notably K and Si) in sorghum seeds under drought stress, despite varying statistical significance for other nutrients. These findings shed light on the mechanisms through which PNS exerts beneficial effects on plant performance under drought stress. By elucidating the complex interactions between PNS application, drought stress, and plant physiology, this study contributes significantly to the development of sustainable agricultural practices aimed at bolstering crop resilience and productivity in water-limited environments.

Dynamic physiological response of tef to contrasting water availabilities.

Global climate change is leading to increased frequency of extreme climatic events, higher temperatures and water scarcity. Tef (Eragrostis tef (Zucc.) Trotter) is an underutilized C4 cereal crop that harbors a rich gene pool for stress resilience and nutritional quality. Despite gaining increasing attention as an "opportunity" crop, physiological responses and adaptive mechanisms of tef to drought stress have not been sufficiently investigated. This study was aimed to characterize the dynamic physiological responses of tef to drought. Six selected tef genotypes were subjected to high-throughput whole-plant functional phenotyping to assess multiple physiological responses to contrasting water regimes. Drought stress led to a substantial reduction in total, shoot and root dry weights, by 59%, 62% and 44%, respectively (averaged across genotypes), and an increase of 50% in the root-to-shoot ratio, relative to control treatment. Drought treatment induced also significant reductions in stomatal conductance, transpiration, osmotic potential and water-use efficiency, increased chlorophyll content and delayed heading. Tef genotypes exhibited diverse water-use strategies under drought: water-conserving (isohydric) or non-conserving (anisohydric), or an intermediate strategy, as well as variation in drought-recovery rate. Genotype RTC-290b exhibited outstanding multifaceted drought-adaptive performance, including high water-use efficiency coupled with high productivity under drought and control treatments, high chlorophyll and transpiration under drought, and faster drought recovery rate. This study provides a first insight into the dynamic functional physiological responses of tef to water deficiency and the variation between genotypes in drought-adaptive strategies. These results may serve as a baseline for further studies and for the development of drought-resistant tef varieties.

Determining Critical Weed Competition at Different Weed Free Periods in Linseed in Holeta District Central Ethiopia

A substantial proportion of linseed yield is lost due to weeds in the Holeta area of Central Ethiopia. The weeds infest the crop fields during the early growth stage and consume growth resources. To protect the crops from weeds, farmers manage their fields using cultural practices. However, there is a knowledge gap between farmers on critical weed removal time for the management of the weeds from the crop. Therefore, it is assumed that determining the weed-free period after the sowing of linseed to control the weeds is necessary. The experiment was designed to determine the suitable weed-free period for the control of weeds and increasing linseed production. The trial was treated with different weed-free periods before 20, 30, 40, 50, and 60 days of sowing; and after 20, 30, 40, 40, and 60 days of sowing, twice hand weeding, weed-free, and control. The treatments were organized in a Randomized Complete Block Design (RCBD) replicated three times. It was found that Galinsogapulviflora was the most dominant weed, contributing to 18% of the total weeds present in the fields. Plots treated with weed-free after 20 days of sowing produced superior results in terms of reduction of weed dry weight by 100%, increased number of bolls per plant by 3.08 folds, stand count by 245%, and grain yield by 11 folds as compared to untreated check respectively. Hence, making weed free of linseed after 20 days of sowing is recommended for the management of various weeds in linseed.

Biodegradable glycine betaine encapsulated chitosan nanoparticles induce the expression of antioxidant enzyme genes to improve drought tolerance in maize

Drought is one of the main abiotic stresses that affect the growth and development of maize crop, thus causing food crises across the world. Nanoparticles are considered an effective tool for improving crop yield by upgrading the plant tolerance mechanism under abiotic stress. In this study, we investigated the role of foliar application of glycine betaine-encapsulated chitosan loaded nanoparticles (LNPs) and unloaded chitosan nanoparticles (NPs) in improving morphological, physiological, biochemical and molecular attributes in two maize varieties, HNG and CZP, grown under drought stress. Petri plates experiment was performed to screen different levels of drought (5 % and 20 %) and nanoparticle concentrations (10, 20 and 40 μg NPs). In the pot experiment, 20 % drought stress along with 20 μg LNPs and 20 μg NPs were used to examine the morphological, physiological and biochemical attributes of maize plants. Drought stress led to a significant reduction in fresh and dry weight, relative water content, root and shoot lengths, photosynthetic pigments, and antioxidant enzyme activities, including catalase, superoxide dismutase, ascorbate peroxidase, and proline content compared to control plants. However, foliar application of LNPs resulted in increased photosynthetic pigments, enhanced antioxidant enzyme activity, and elevated proline content under both control and drought-stressed conditions. Conversely, malondialdehyde (MDA) content decreased significantly with the application of LNPs and NPs alone under stress conditions. Moreover, nanoparticles also enhanced the relative expression levels of antioxidant genes, ZmAPX, ZmCAT, and ZmSOD. These findings highlight the potential of LNPs as an ecofriendly which helps in ameliorating drought stress in maize, and other plants.

Pomegranate (Punica granatum L.) growth and biochemical alterations in response to meloidogyne incognita infection, minerals, and nano-fertilizers

The effects of four inoculum levels (500, 1,000, 2,000, or 4,000 second-stage juveniles (J2) per plant) of the root-knot nematode, Meloidogyne incognita, on two pomegranate cultivars (‘Manfalouty’ and ‘Wonderful’) were investigated under greenhouse conditions in response to plant inorganic and organic chemical concentrations. Furthermore, the effects of six commercial chemical fertilizers (inorganic fertilizers and nano-fertilizers) on plant growth and nematode reproduction were also studied. Both cultivars recorded the highest gall formation, embedded stages, and final nematode population at the inoculum dosage of 2,000 J2/plant. The highest reproductive rate was achieved with 500 J2/plant, while the lowest rate was observed with 4,000 J2/plant on both cultivars. ‘Wonderful’, at all M. incognita inoculum levels, was more sensitive to nematode infestation than ‘Manfalouty’. ‘Wonderful’ showed a greater reduction in fresh and dry plant weights than ‘Manfalouty’ at 2,000 and 4,000 J2/plant. In both cultivars, the concentrations of N, P, and K decreased with increasing nematode inoculum levels. This decline was more pronounced in ‘Manfalouty’ than in ‘Wonderful’. The nano-fertilizers, Hyper Feed®, and Hyper Feed Solo® reduced all nematode parameters but only in ‘Wonderful’. Treatment with Hyper Feed® resulted in the highest percentage increases in all plant growth parameters in ‘Wonderful’. Total carbohydrate concentration was increased in ‘Manfalouty’ treated with the nano-fertilizers, especially with Hyper Feed®. Also, concentrations of total phenols and tannins increased in ‘Wonderful’ when treated with either nano-fertilizer. Generally, both nano-fertilizers showed an increase in plant N levels. We recommend using nano-fertilizers in integrated pest management (IPM) programs on pomegranate where they improved plant growth parameters and reduced nematode multiplication parameters more markedly than inorganic fertilizers.

Amelioration of chromium toxicity in wheat plants through exogenous application of nano silicon

Chromium (Cr) contamination in agricultural soils poses a risk to crop productivity and quality. Emerging nano-enabled strategies show great promise in remediating soils contaminated with heavy metals and enhancing crop production. The present study was aimed to investigate the efficacy of nano silicon (nSi) in promoting wheat growth and mitigating adverse effects of Cr-induced toxicity. Wheat seedlings exposed to Cr (K2Cr2O7) at a concentration of 100 mg kg−1 showed significant reductions in plant height (29.56%), fresh weight (35.60%), and dry weight (38.92%) along with enhanced Cr accumulation in roots and shoots as compared to the control plants. However, the application of nSi at a concentration of 150 mg kg−1 showcased substantial mitigation of Cr toxicity, leading to a decrease in Cr accumulation by 27.30% in roots and 35.46% in shoots of wheat seedlings. Moreover, nSi exhibited the capability to scavenge oxidative stressors, such as hydrogen peroxide (H2O2), and malondialdehyde (MDA) and electrolyte leakage, while significantly enhancing gas exchange parameters, total chlorophyll content, and antioxidant activities (enzymatic and nonenzymatic) in plants grown in Cr-contaminated soil. This study further found that the reduced Cr uptake by nSi application was due to downregulating the expression of HMs transporter genes (TaHMA2 and TaHMA3), alongwith upregulating the expression of antioxidant-responsive genes (TaSOD and TaSOD). The findings of this investigation highlight the remarkable potential of nSi in ameliorating Cr toxicity. This enhanced efficacy could be ascribed to the distinctive size and structure of nSi, which augment its ability to counteract Cr stress. Thus, the application of nSi could serve as a viable solution for production of crops in metal contaminated soils, offering an effective alternative to time-consuming and costly remediation techniques.

Chemical Characterization and Effect of a Lactobacilli-Postbiotic on Streptococcus mutans Biofilm In Vitro.

Postbiotic is the term used to define the soluble factors, metabolic products, or byproducts released by live probiotic bacteria or after its lysis. The objective of this study was to carry out the chemical characterization of the postbiotic of Lacticaseibacillus rhamnosus LR-32 and to evaluate its in vitro effect on the development of the Streptococcus mutans biofilm. After the cultivation of the probiotic strain, the postbiotic was extracted by centrifuging the culture and filtering the supernatant. This postbiotic was characterized by using gas chromatography coupled with mass spectrometry (GC-MS), and then it was used to determine the growth inhibition of S. mutans in its planktonic form; additionally, its effects on the following parameters in 48 h biofilm were evaluated: viable bacteria, dry weight, and gene expression of glucosyltransferases and VicR gene. The control group consisted of the biofilm without any treatment. A paired t-test was performed for statistical analysis, with the p-value set at 5%. Seventeen compounds of various chemical classes were identified in the postbiotic, including sugars, amino acids, vitamins, and acids. The treatment with the postbiotic led to an inhibition of the growth of S. mutans in its planktonic form, as well as a decrease in the number of viable bacteria, reduction in dry weight, and a negative regulation of the gene expression of gtfB, gtfC, gtfD, and vicR in its biofilm state, compared with the nontreated group (p < 0.05). The postbiotic of L. rhamnosus impaired the development of S. mutans biofilm.

Behavior of Several Peanut Genotypes Under Sunlight and Water Deficit Condition

Drought and shade stress often occur together in peanut plants. Sunlight and water are the main factors that determine the growth of peanut plants. This study aimed to determine the behavior of several peanut genotypes under conditions of sunlight and water deficit. This research was conducted using a Completely Randomized Design-Split Plot Design with three replications. The treatments to be tested were double stresses (sun light and water deficit) and no stress (control) factors as the main plot and peanut genotype factors, namely Takar-1, Domba, Bison, G2T5, and G19-UI as subplots. The results showed that the peanut genotypes had different behaviors under double stresses (sunlight and water deficit). Peanut plants under double stress caused a reduction in pod dry weight, number of pods, root dry weight, and chlorophyll-a levels compared to those without stress. Peanut genotype G19-UI resulted in the lowest percentage reduction in pod dry weight and number of pods per plant, namely 58.79% and 43.75% under double stresses, respectively

Influence of Drought Stress and Foliar Application of Salicylic Acid on Early Vegetative Stage of Cacao

Cacao (Theobroma cacao L.) is noted to have a low tolerance to drought and is, therefore, not resilient to prolonged dry periods. The study sought to evaluate the morpho-anatomical and physiological responses of two clonal seedlings of cacao BR25 and K9 under drought stress and to explore the potential alleviating effects of salicylic acid (SA) at concentrations of 0.5 and 1.0 mM on the early vegetative stage. Eleven-month-old BR25 and K9 cacao were pre-treated with foliar application of 0.5 and 1.0-mM SA for 2 wk before the onset of drought conditions. Well-watered and drought seedlings with no pre-treatments served as the control. Water was withheld for 20 d, after which rewatering resumed for 3 mo. Results revealed that after 20 d of drought, both clonal varieties experienced a significant decline in relative water content (RWC) and increased ascorbate peroxidase (APX) and catalase activity. Changes in stem diameter were observed after a rewatering period of 3 mo. K9 exhibited a noticeable reduction in root and shoot dry weight and stomatal aperture after 20 d of drought, whereas BR25 showed a decrease in total chlorophyll content and chlorophylls a and b. Furthermore, the results of the study suggest that 0.5-mM SA has the potential to mitigate the drastic effects during drought in BR25 and K9 cacao by improving RWC, stomatal length, and width. On the other hand, 1.0- mM SA has the potential to alleviate the effects of drought experienced earlier on by improving root dry weight and APX activities of the seedlings.

Mechanism of salt tolerance in the endangered semi-mangrove plant Barringtonia racemosa: anatomical structure and photosynthetic and fluorescence characteristics.

To elucidate the mechanisms governing the salt tolerance of the endangered semi-mangrove plant Barringtonia racemosa, the biomass, photosynthetic and fluorescent characteristics, and anatomical structure of B. racemosa were studied under low, medium and high salt stress. The results showed that the stem dry weight, net photosynthetic rate, intercellular CO2 concentration, Fv/Fm, and ΦPSI of B. racemosa decreased under high salt stress, which led to a significant reduction in total dry weight. Stem dry weight was significantly positively correlated with the thickness of palisade tissue and significantly negatively correlated with the thickness of the epidermis of roots and xylem of stems. Therefore, a stable net photosynthetic rate and intercellular CO2 concentration, an increase in Fv/Fm and ΦPSI, an increase in or stable palisade tissue and spongy mesophyll of leaves and an increase in xylem thickness of the stem and epidermis, outer cortex, and stele diameter of roots could contribute to the salt tolerance of B. racemosa.

Melatonin mitigation of herbicide-induced injury to guar crop improves nodulation

The guar plant, or cluster bean, forms a weak symbiosis with rhizobia, and it is sensitive to herbicides. We hypothesized that application of melatonin to guar seeds, leaves, or both protect against metabolic injury from eight herbicides, and strengthening the symbiosis. Imazethapyr and 2,4-DB did not injure guar and its rhizobium partner. Root nodulation was severely damaged with pendimethalin and less with bentazon. A reduction in guar's total dry weight, which ranged from 14% with bentazon to 28% with bromoxynil, was observed, indicating metabolic stress. When no herbicide was applied, seeds coated with melatonin had no effect. When herbicides were applied, it partially mitigated herbicide-induced injury. Foliar application of melatonin protected guar completely against bentazon, bromoxynil, and oxyfluorfen, protected nodulation.

N-terminal truncation of PhaCBP-M-CPF4 and its effect on PHA production

BackgroundAmong the polyhydroxyalkanoate (PHA), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] is reported to closely resemble polypropylene and low-density polyethylene. Studies have shown that PHA synthase (PhaC) from mangrove soil (PhaCBP-M-CPF4) is an efficient PhaC for P(3HB-co-3HHx) production and N-termini of PhaCs influence its substrate specificity, dimerization, granule morphology, and molecular weights of PHA produced. This study aims to further improve PhaCBP-M-CPF4 through N-terminal truncation.ResultsThe N-terminal truncated mutants of PhaCBP-M-CPF4 were constructed based on the information of the predicted secondary and tertiary structures using PSIPRED server and AlphaFold2 program, respectively. The N-terminal truncated PhaCBP-M-CPF4 mutants were evaluated in C. necator mutant PHB−4 based on the cell dry weight, PHA content, 3HHx molar composition, molecular weights, and granule morphology of the PHA granules. The results showed that most transformants harbouring the N-terminal truncated PhaCBP-M-CPF4 showed a reduction in PHA content and cell dry weight except for PhaCBP-M-CPF4 G8. PhaCBP-M-CPF4 G8 and A27 showed an improved weight-average molecular weight (Mw) of PHA produced due to lower expression of the truncated PhaCBP-M-CPF4. Transformants harbouring PhaCBP-M-CPF4 G8, A27, and T74 showed a reduction in the number of granules. PhaCBP-M-CPF4 G8 produced higher Mw PHA in mostly single larger PHA granules with comparable production as the full-length PhaCBP-M-CPF4.ConclusionThis research showed that N-terminal truncation had effects on PHA accumulation, substrate specificity, Mw, and granule morphology. This study also showed that N-terminal truncation of the amino acids that did not adopt any secondary structure can be an alternative to improve PhaCs for the production of PHA with higher Mw in mostly single larger granules.