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Heavy metal cadmium (Cd) is toxic to organisms. Mulberry (Morus alba L.) is a fast-growing perennial that is also an economical Cd phytoremediation material with large biomass. However, the molecular mechanisms underlying its Cd tolerance remain unclear. Here, we reveal the physiological and molecular mechanisms underlying Cd toxicity under varying calcium (Ca) treatments. First, under low-Ca treatment (0.1 mM Ca), mulberry growth was severely inhibited and the root surface structure was damaged by Cd stress. Second, electrophysiological data demonstrated that 0.1 mM Ca induced an increased Cd 2+ influx, leading to its accumulation in the entire root and root cell walls. Third, high-Ca treatment (10 mM Ca) largely alleviated growth inhibition, activated antioxidant enzymes, increased Ca content, decreased Cd 2+ flux, and inhibited Cd uptake by roots. Finally, 0.1 mM Ca resulted in the activation of metal transporters and the disruption of Ca signaling-related gene expression, which facilitated Cd accumulation in the roots, aggravating oxidative stress. These adverse effects were reversed by treatment with 10 mM Ca. This study preliminarily revealed the mechanism by which varying Ca levels regulate Cd uptake and accumulation in mulberry roots, provided an insight into the interrelationships between Ca and Cd in the ecological and economic tree mulberry and offered a theoretical basis for Ca application in managing Cd pollution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The mulberry fruit is prized for its superior nutrition value and abundant color due to its high flavone content. To enhance comprehension of flavone biogenesis induced by external hormones, we sprayed exogenous ethylene (ETH), indoleacetic acid (IAA) and spermine (SPM) on mulberry fruit (Hongguo 2) during its color-changed period. The levels of anthocyanin, titratable acid, soluble sugar and endogenous hormones were determined after hormone treatment, integrated transcriptome and metabolome analysis were performed for mechanism exploration. Our results indicated that exogenous ETH, SPM, and IAA play important roles in mulberry ripening, including acid reduction, sugar increase and flavonoid synthesis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Upon a sudden transition from low to high light, electrons transported from photosystem II (PSII) to PSI should be rapidly consumed by downstream sinks to avoid the over-reduction of PSI. However, the over-reduction of PSI under fluctuating light might be accelerated if primary metabolism is restricted by low stomatal conductance. To test this hypothesis, we measured the effect of diurnal changes in stomatal conductance on photosynthetic regulation under fluctuating light in tomato ( Solanum lycopersicum ) and common mulberry ( Morus alba ). Under conditions of high stomatal conductance, we observed PSI over-reduction within the first 10 s after transition from low to high light. Lower stomatal conductance limited the activity of the Calvin-Benson-Bassham cycle and aggravated PSI over-reduction within 10 s after the light transition. We also observed PSI over-reduction after transition from low to high light for 30 s at the low stomatal conductance typical of the late afternoon, indicating that low stomatal conductance extends the period of PSI over-reduction under fluctuating light. Therefore, diurnal changes in stomatal conductance significantly affect the PSI redox state under fluctuating light. Moreover, our analysis revealed an unexpected inhibition of cyclic electron flow by the severe over-reduction of PSI seen at low stomatal conductance. In conclusion, stomatal conductance can have a large effect on thylakoid reactions under fluctuating light.

Root-knot nematodes cause damage to several crops and the importance of each species can vary according with the crop and the agricultural region. In Brazil, Meloidogyne javanica is one of the most important nematode species parasitizing mulberry. To define management strategies, it is important to know if the crop species is damaged by the parasitism of the nematode and the best choices for control, as the use of nematicides. Biological nematicides have been extensively used in Brazil, but no information regarding its efficiency to control M. javanica in mulberry is available. Besides, it is not known if biological nematicides could improve the quality of leaves or if they alter the nutrient composition of leaves, which could interfere in the development of the silkworms that are feed with these leaves or in the quality of the silk produced. With the aim to address these questions, we propose a study that will start in the phenotyping of the main Brazilian mulberry cultivars to Meloidogyne species, passing through the test of efficiency of biological nematicides in the control of M. javanica in mulberry cultivar Miura, evaluation of the amount and quality of leaves produced and, using these leaves to feed silkworms, in the analyzes of the impact of these diet in the health of silkworms, and in the production and quality of the silk., Competing Interests: No authors have competing interests.

Mulberry (Morus atropurpurea) is an economically important woody tree and has great potential for the remediation of heavy metals. To investigate how cadmium accumulates and its detoxification in mulberry, we assessed the physiological and transcriptomic effects of cadmium contamination and as well as its chemical forms and subcellular distribution. Cadmium significantly inhibited mulberry plant growth and primarily accumulated in mulberry roots. Antioxidant enzymes were induced by cadmium in all tissues of mulberry. Subcellular fractionation analyses of cadmium indicated that the majority was compartmentalized in soluble fraction in roots while it mainly located in cell wall in leaves and stems. The greatest amount of the cadmium was integrated with proteins and pectates in all mulberry tissues. RNA-seq transcriptomic analyses of mulberry roots revealed that various metabolic pathways involved in cadmium stress response such as RNA regulation, hormone metabolism, and response to stress, secondary metabolism, as well as signaling, protein metabolism, transport, and cell-wall metabolism. These results will increase our understanding of the molecular mechanisms of cadmium detoxification in mulberry and provide new insights into engineering woody plants for phytoremediation., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In order to find out the response mechanism of nitrogen assimilation and glutamine/glutamine family of amino acids metabolism in mulberry ( Morus alba L.) leaves under NaCl and NaHCO 3 stress, and to reveal its role in salt alkali adaptation. The effects of the nitrogen metabolism of mulberry leaves were studied under 100 mmol L -1 NaCl and NaHCO 3 stress.The results showed that the activity of NR and the content of TN and SP did not change significantly, the expression of NiR, Fd-NiR, Fd-NiR gene and theactivity of NiR increased significantly under NaCl stress, but nitrogen assimilation was inhibited under NaHCO 3 stress. NaCl stress had no significant effect on the expression and activity of GS and GOGAT in mulberry leaves. Under NaHCO 3 stress, the expression of Fd-GOGAT, Fd-GOGAT2, Fd-GOGAT gene, and the activity of GS and GOGAT were significantly decreased. NaCl stress can promote the accumulation of Pro, Put and Spd in mulberry leaves. The accumulation of Pro under NaHCO 3 stress is greater than that under NaCl stress. NaCl stress also induced the up-regulation of GAD, GAD1 and GAD1 gene expression, so promoting the synthesis of GABA may be an adaptive mechanism for mulberry to cope with NaCl stress, but the expression of GAD did not change significantly and GAD gene expression lower than CK under NaHCO 3 stress. Although both NaCl and NaHCO 3 stress could promote the synthesis of GSH by up-regulation of GCLM expression, GSH under NaHCO 3 stress was significantly higher than that under NaCl stress, the content of H 2 O 2 was still significantly higher than that of NaCl stress, that means GSH may not play a key role in alleviating the oxidative damage in mulberry leaves caused by salt and alkali.

To explore the mechanism of how lead (Pb) and cadmium (Cd) stress affects photosynthesis of mulberry (Morus alba L.), we looked at the effects of different concentrations of Pb and Cd stress (at 100 and 200 μmol L -1 ), which are two heavy metal elements, on leaf chlorophyll (Chl), photosynthesis gas exchange, Chl fluorescence, and reactive oxygen species (ROS) metabolism in mulberry leaves. The results showed that higher concentrations of Pb and Cd reduced leaf Chl content, especially in Chl a where content was more sensitive than in Chl b. Under Pb and Cd stress, the photosynthetic carbon assimilation capacity of mulberry leaves was reduced, which was a consequence of combined limitations of stomatal and non-stomatal factors. The main non-stomatal factors were decreased photosystem II (PSII) and photosystem I (PSI) activity and carboxylation efficiency (CE). Damage to the donor side of the PSII reaction center was greater than the acceptor side. After being treated with 100 μmol L -1 of Pb and Cd, mulberry leaves continued to be able to dissipate excess excitation energy by starting non-photochemical quenching (NPQ), but when Pb and Cd concentrations were increased to 200 μmol L -1 , the protection mechanism that depends on NPQ was impaired. Excessive excitation energy from chloroplasts promoted a great increase of ROS, such as superoxide anion (O 2 •- ) and H 2 O 2 . Moreover, under high Pb and Cd stress, superoxide dismutase (SOD) and ascorbate peroxidase (APX) were also inhibited to some extent, and excessive ROS also resulted in a significantly higher degree of oxidative damage. Compared with Cd, the effect of Pb stress at the same concentration level displayed a significantly lower impact on Chl content, photosynthetic carbon assimilation, and stomatal conductance. Meanwhile, Pb stress mainly damaged activity of the oxygen-evolving complex (OEC) located on PSII donor side, but it reduced the electronic pressure on the PSII acceptor side and PSI. Furthermore, under Pb stress, the NPQ, SOD, and APX activity were all significantly higher than those under Cd stress. Thus under Pb stress, the degree of photoinhibition and oxidative damage of PSII and PSI in mulberry leaves were significantly lower than under Cd stress., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In this paper, the effects of 100 mM NaCl and NaHCO 3 stress on reactive oxygen species (ROS) and physiological and proteomic aspects of ROS metabolism in mulberry seedling leaves were studied. The results showed that NaCl stress had little effect on photosynthesis and respiration of mulberry seedling leaves. Superoxide dismutase (SOD) activity and the expression of related proteins in leaves increased by varying degrees, and accumulation of superoxide anion (O 2 · - ) not observed. Under NaHCO 3 stress, photosynthesis and respiration were significantly inhibited, while the rate of O 2 · - production rate and H 2 O 2 content increased. The activity of catalase (CAT) and the expression of CAT (W9RJ43) increased under NaCl stress. In response to NaHCO 3 stress, the activity and expression of CAT were significantly decreased, but the ability of H 2 O 2 scavenging of peroxidase (POD) was enhanced. The ascorbic acid-glutathione (AsA-GSH) cycle in mulberry seedling leaves was enhancement in both NaCl and NaHCO 3 stress. The expression of 2-Cys peroxiredoxin BAS1 (2-Cys Prx BAS1), together with thioredoxin F (TrxF), thioredoxin O1 (TrxO1), thioredoxin-like protein CITRX (Trx CITRX), and thioredoxin-like protein CDSP32 (Trx CDSP32) were significantly increased under NaCl stress. Under NaHCO 3 stress, the expression of the electron donor of ferredoxin-thioredoxin reductase (FTR), together with Trx-related proteins, such as thioredoxin M (TrxM), thioredoxin M4 (TrxM4), thioredoxin X (TrxX), TrxF, and Trx CSDP32 were significantly decreased, suggesting that the thioredoxin-peroxiredoxin (Trx-Prx) pathway's function of scavenging H 2 O 2 of in mulberry seedling leaves was inhibited. Taken together, under NaCl stress, excessive production of O 2 · - mulberry seedlings leaves was inhibited, and H 2 O 2 was effectively scavenged by CAT, AsA-GSH cycle and Trx-Prx pathway. Under NaHCO 3 stress, despite the enhanced functions of POD and AsA-GSH cycle, the scavenging of O 2 · - by SOD was not effective, and that of H 2 O 2 by CAT and Trx-Prx pathway were inhibited; and in turn, the oxidative damage to mulberry seedling leaves could not be reduced., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Chlorophyll (Chl) and effective photoprotective mechanism are important prerequisites to ensure the photosynthetic function of plants under stress. In this study, the effects of 100 mmol L -1 NaCl and NaHCO 3 stress on chlorophyll synthesis and photosynthetic function of mulberry seedlings were studied by physiological combined with proteomics technology. The results show that: NaCl stress had little effect on the expression of Chl synthesis related proteins, and there were no significant changes in Chl content and Chl a:b ratio. However, 13 of the 15 key proteins in the process of Chl synthesis were significantly decreased under NaHCO 3 stress, and the contents of Chl a and Chl b were significantly decreased (especially Chl a). Although stomatal conductance (G s ) decreased significantly under NaCl stress, net photosynthetic rate (P n ), PSII maximum photochemical efficiency (F v /F m ) and electron transfer rate (ETR) did not change significantly, but under NaHCO 3 stress, not only G s decreased significantly, PSII activity and photosynthetic carbon were the same. In the photoprotective mechanism under NaCl stress, NAD(P)H dehydrogenase (NDH)-dependent cyclic electron flow (CEF) enhanced, the expression of related proteins subunit, ndhH, ndhI, ndhK, and ndhM, the key enzyme of the xanthophyll cycle, violaxanthin de-epoxidase (VDE) were up-regulated, the ratio of (A + Z)/(V + A + Z) and non-photochemical quenching (NPQ) was increased. The expressions of proteins FTR and Fd-NiR were also significant up-regulated under NaCl stress, Fd-dependent ROS metabolism and nitrogen metabolism can effectively reduce the electronic pressure on Fd. Under NaHCO 3 stress, the expressions of NDH-dependent CEF related proteins subunit (ndhH, ndhI, ndhK, ndhM and ndhN), VDE, ZE, FTR, Fd-NiR and Fd-GOGAT, were significant down-regulated, and ZE, CP26, ndhK, ndhM, Fd-NiR, Fd-GOGAT and FTR genes expression also significantly decreased, the photoprotective mechanism, like the xanthophyll cycle，CEF and Fd-dependent ROS metabolism and nitrogen metabolism might be damaged, resulting in the inhibition of PSII electron transfer and carbon assimilation in mulberry leaves under NaHCO 3 stress., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Fast growing woody plants are proposed for potential application for phytoremediation of contaminated soil. In this study, the plant growth, physiological responses, mineral element uptake, and phytoremediation potential of the woody plant Morus alba L. were studied in different levels of Cd-contaminated soil through dynamic sampling (30, 60, 120, and 180 d). The results indicated that M. alba L. had strong physiological coordination, tolerance and detoxification capacity in response to Cd in contaminated soil. Compared with the control, the photosynthetic pigment content in M. alba L. leaves was significantly suppressed during initial cultivation (30-60 d) and the malonaldehyde (MDA) content and electrolyte leakage (EL) were increased from 30 to 120 d of cultivation. Furthermore, the uptake of Cu, Mn, and Zn in plant tissues was imbalanced throughout cultivation (30-180 d) under 55 mg·kg -1 Cd stress. However, the chlorophyll a, chlorophyll b, carotenoid, soluble protein, and soluble sugar contents and the peroxidase (POD) and ascorbate peroxidase (APX) activities in plant leaves, as well as the uptake of macronutrients (K, Ca, and Mg) in plant stems and leaves were maintained at normal levels. Furthermore, the catalase (CAT) activities in plant leaves and the Ca and Mg contents in plant roots were significantly (p < 0.05) enhanced in response to Cd stress after 180 d of cultivation. Furthermore, the biomass of M. alba L. was significantly increased with cultivation time in Cd-contaminated soil. Therefore, normal photosynthesis, antioxidant protection, and macronutrient regulation contribute to M. alba L. with high tolerance to Cd. Moreover, the uptake and total extraction amount of Cd in aboveground M. alba L. were significantly (p < 0.05) increased with both the plant growth period and soil Cd level, and the maximum amount of Cd reached up to 340.5 μg·plant -1 . Thus, M. alba L. can be regarded as a potential candidate for phytoremediation in Cd-contaminated sites., (Copyright © 2019 Elsevier Inc. All rights reserved.)

In order to explore the response and adaptation mechanisms of photosynthesis of the leaves of mulberry (Morus alba L.) seedlings to saline-alkali stress. Photosynthetic activity, and the response of related proteomics of M. alba seedling leaves under NaCl and NaHCO 3 stress were studied by using chlorophyll fluorescence and gas exchange technique combined with TMT proteomics. The results showed that NaCl stress had no significant effect on photosystem II (PSII) activity in M. alba seedling leaves. In addition, the expressions of proteins of the PSII oxygen-evolving complex (OEE3-1 and PPD4) and the LHCII antenna (CP24 10A, CP26, and CP29) were increased, and the photosystem I (PSI) activity in the leaves of M. alba seedlings was increased, as well as expressions of proteins, such as PsaF, PsaG, PsaH, PsaL, PsaN, and Ycf4. Under NaHCO 3 stress, the activity of PSII and PSI and the expression of their protein complexes and the electron transfer-related proteins significantly decreased. NaCl stress had little effect on RuBP regeneration during dark reaction in the leaves and the expressions of glucose synthesis related proteins and net photosynthetic rate (P n ) did not decrease significantly. The leaves could adapt to NaCl stress by reducing stomatal conductance (G s ) and increasing water use efficiency (WUE). Under NaHCO 3 stress, the expression of dark reaction-related proteins was mostly down-regulated, while G s was reduced, which indicated that non-stomatal factors can be responsible for inhibition of carbon assimilation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Mulberroside A, oxyresveratrol and resveratrol, commonly found in Morus alba L., are potent anti-aging phytostilbenes. In this study, the effect of the addition of 2-hydroxypropyl-β-cyclodextrin on the levels of phytostilbenes in M. alba callus cultures was investigated. Commercial cyclodextrin was used in the hydrolytic and culture processes of the M. alba callus cultures. The hydrolytic study indicated that 2-hydroxypropyl-β-cyclodextrin acted as a retardant for stilbenoid hydrolysis. It reduced mulberroside A deglycosylation and stabilised oxyresveratrol. The elicitation result showed that extracellular oxyresveratrol was increased by adding 2-hydroxypropyl-β-cyclodextrin to the culture media of both free and immobilised M. alba callus (>730-fold and >169-fold, respectively) compared with those of the control. However, the intracellular mulberroside A levels in the treatment groups did not increase compared with those of the control. The results show that the addition of 2-hydroxypropyl-β-cyclodextrin significantly changed the patterns and levels of the stilbenoids in M. alba callus cultures.

Efficient disposal of urban sewage sludge, material that typically contains high concentrations of heavy metals, has become a significant concern worldwide. The empirical purpose of the current study is to investigate physical and chemical parameters of composted sludge and garden waste at different ratios. Results reveal that nutrient content has significantly increased after the application of composts as compared to the controlled sample. Composting garden waste with sewage sludge at a 1:1 ratio promoted plant growth and gradually showed superiority in the later period. The maximum plant height, total biomass, and crown width of mulberry trees increased by 12.1, 33.5, and 45.7%, respectively, compared with the control treatment. The bound to organic matter of Hg, Cr, and Pb in the sewage sludge increased after composting with garden waste, and the mulberry exhibited a high ability to accumulate Ni and Cd from the soil. Conclusively, compared to using the two soil mediums separately, composting garden waste and sewage sludge together is beneficial for soil improvement and vegetation growth.

Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the most acute infectious diseases in silkworm, which has led to great economic loss in sericulture. Previous study showed that the content of secondary metabolites in mulberry leaves, particularly for moracin N, was increased after UV-B irradiation. In this study, the BmNPV resistance of silkworms reared on UV-B treated and moracin N spread mulberry leaves was improved. To uncover the mechanism of enhanced BmNPV resistance, silkworm midguts from UV-B treated mulberry leaves (BUM) and moracin N (BNM) groups were analyzed by SWATH-based proteomic technique. Of note, the abundance of ribosomal proteins in BUM and BNM groups was significantly changed to maintain the synthesis of total protein levels and cell survival. While, cytochrome c oxidase subunit II, calcium ATPase and programmed cell death 4 involved in apoptotic process were up-regulated in BNM group. Expressions of lipase-1, serine protease precursor, Rab1 protein, and histone genes were increased significantly in BNM group. These results suggest that moracin N might be the main active component in UV-B treated mulberry leaves which could improve the BmNPV-resistance of silkworm through promoting apoptotic cell death, enhancing the organism immunity, and regulating the intercellular environment of cells in silkworm. It also presents an innovative process to reduce the mortality rate of silkworms infected with BmNPV., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Abundance of CaCO3 rich soil dust is a typical feature of atmospheric environment in the Indian region. During prevailing dry weather conditions, dustfall is deposited onto the foliar surfaces of plant affecting their morphology, stomata and the levels of biochemical constituents. This study reports the chemical characteristics of dustfall, its effect on foliar morphology and biochemical constituents of a medicinal plant (Morus alba) at two sites which are differentiated on the basis of landuse pattern, viz., (i) residential, Jawaharlal Nehru University (JNU), and (ii) industrial, Sahibabad (SB), located in the National Capital Region (NCR) of Delhi. Dustfall was characterized for major anions (F(-), Cl(-), NO3 (-) and SO4 (--)) and cations (Na(+), NH4 (+), K(+), Mg(++) and Ca(++)). Biochemical parameters such as chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, proline and ascorbic acid were determined in foliar samples. The results showed that the dustfall fluxes of all the major ions were found to be higher at the industrial site (SB) as compared to the residential site (JNU). Foliar analysis revealed that the levels of biochemical parameters were more affected at SB site due to higher levels of dust SO4 (--) contributed by various anthropogenic sources resulting in more stressful conditions affecting the biochemistry of the plant. The possible entry pathways for dust SO4 (--) into foliar cells are also discussed in the paper. It was noticed that the deposition of urban dust was responsible for the damage of trichome, epidermis, cuticle and stomatal guard cells significantly affecting foliar morphology. SB exhibited more damage to these morphological parts suggesting that industrial dust is harmful to the plants.

Current study was undertaken to elucidate the responses of short rotation coppice (SRC) mulberry under elevated CO2 atmosphere (550μmolmol(-1)). Throughout the experimental period, elevated CO2 grown mulberry plants showed significant increase in light saturated photosynthetic rates (A') by increasing intercellular CO2 concentrations (Ci) despite reduced stomatal conductance (gs). Reduced gs was linked to decrease in transpiration (E) resulting in improved water use efficiency (WUE). There was a significant increase in carboxylation efficiency (CE) of Rubisco, apparent quantum efficiency (AQE), light and CO2 saturated photosynthetic rates (AMAX), photosynthetic nitrogen use efficiency (PNUE), chlorophyll a fluorescence characteristics (FV/FM and PIABS), starch and other carbohydrates in high CO2 grown plants which clearly demonstrate no photosynthetic acclimation in turn resulted marked increase in above and below ground biomass. Our results strongly suggest that short rotation forestry (<1year) with mulberry plantations should be effective to mitigate raising CO2 levels as well as for the production of renewable bio-energy., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Key Message: Group1 remorins may help the plants to optimize their growth under adverse conditions by their involvement in mediating osmotic stress responses in plants., Abstract: Mulberry (Morus indica), a deciduous woody tree, serves as the cardinal component of the sericulture industry. Genomic endeavors in sequencing of mulberry ESTs provided clues to stress-specific clones, but their functional relevance remains fragmentary. Therefore in this study, we assessed the functional significance of a remorin gene family member that was identified in leaf ESTs. Remorins represent a large, plant-specific multigene family gaining importance in recent times with respect to their role in plant-microbe interactions, although their role in response to environmental stresses remains speculative as in vivo functions of remorin genes are limited. Mulberry remorin (MiREM) localizes to plasma membrane and is ubiquitously present in all plant organs. Expression analysis of MiREM by northern analysis reveals that its transcript increases under different abiotic stress conditions especially during dehydration and salt stress, implicating it in regulation of stress signaling pathways. Concomitantly, transgenic Arabidopsis plants overexpressing heterologous remorin show tolerance to dehydration and salinity at the germination and seedling stages as revealed by percentage germination, root inhibition assays, fresh weight and activity of photosystem II. This study predicts the possible function of group 1 remorin gene in mediating osmotic stress thus bringing novel perspectives in understanding the function of remorins in plant abiotic stress responses.

Coping with different kinds of biotic and abiotic stresses is the foundation of sustainable agriculture. Although conventional breeding and marker-assisted selection are being employed in mulberry (Morus indica L.) to develop better varieties, nonetheless the longer time periods required for these approaches necessitates the use of precise biotechnological approaches for sustainable agriculture. In an attempt to improve stress tolerance of mulberry, an important plant of the sericulture industry, an encoding late embryogenesis abundant gene from barley (HVA1) was introduced into mulberry plants by Agrobacterium-mediated transformation. Transgenic mulberry with barley Hva1 under a constitutive promoter actin1 was shown to enhance drought and salinity tolerance. Here, we report that overexpression of barley Hva1 also confers cold tolerance in transgenic mulberry. Further, barley Hva1 gene under control of a stress-inducible promoter rd29A can effectively negate growth retardation under non-stress conditions and confer stress tolerance in transgenic mulberry. Transgenic lines display normal morphology to enhanced growth and an increased tolerance against drought, salt and cold conditions as measured by free proline, membrane stability index and PSII activity. Protein accumulation was detected under stress conditions confirming inductive expression of HVA1 in transgenics. Investigations to assess stress tolerance of these plants under field conditions revealed an overall better performance than the non-transgenic plants. Enhanced expression of stress responsive genes such as Mi dnaJ and Mi 2-cysperoxidin suggests that Hva1 can regulate downstream genes associated with providing abiotic stress tolerance. The investigation of transgenic lines presented here demonstrates the acquisition of tolerance against drought, salt and cold stress in plants overexpressing barley Hva1, indicating that Arabidopsis rd29A promoter can function in mulberry.

This study investigates the use of a natural polysaccharide isolated from mulberry leaves as a nonviral gene vector. Ethylenediamine is chemically grafted to the backbone of a polysaccharide from mulberry leaves (MPS) to acquire nucleic acid binding affinity. A particle-size observation indicates that the cationic mulberry leaf polysaccharide (CMPS) can efficiently combine with plasmid transforming growth factor β1 (TGF-β1) to form nanoscaled particles. In addition, the electrophoresis assay indicates a retarded plasmid migration when the CMPS/pTGF-β1 weight ratio is increased to 30:1. The in vitro cell transfection experiment is performed based on bone marrow mesenchymal stem cells (MSCs) derived from rat femurs and tibias, and the findings reveal that the complex with a CMPS/pTGF-β1 weight ratio of 50:1 exhibits the highest cell transfection effect, which is significantly higher than that of branched poly(ethyleneimine) (PEI) (25 kDa; p = 0.001, Student's t-test) and slightly higher than Lipofectamine 2000. Moreover, the cytotoxicity assay also demonstrates that all of these tested complexes and the plasmid TGF-β1 are nontoxic to mesenchymal stem cells (MSCs). The results of the living cell imaging confirm that more of the CMPS/plasmid TGF-β1 nanoparticles can be taken up and at a faster rate by the MSCs than by the positive control Lipofectamine 2000; these data are consistent with the transfection efficiency data. Together, these results suggest that the CMPS/pTGF-β1 nanoparticle can potentially be developed into a promising alternative for the transfer of therapeutic genes into cells., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Effects of aqueous chlorine dioxide (ClO(2)) treatment on nutritional components and shelf-life of mulberry fruit (Morus alba L.) were investigated. Mulberry fruit were immersed into 20, 60, and 80 mg/l ClO(2) solutions for 5, 10, and 15 min, respectively. Mulberries were then rinsed with potable tap water for 1 min and stored at -1°C for 14 d. ClO(2) treatment was effective in retention of flavonoid, ascorbic acid, reducing sugar, and titratable acid. ClO(2) concentration and treatment time were significant factors affecting ClO(2) treatment. The shelf-life of the samples treated by 60 mg/l ClO(2) for 15 min was extended to 14 d compared to 8 d for the control. No ClO(2), ClO(2)(-), or ClO(3)(-) residues were detected in samples treated by 60 mg/l ClO(2) for 15 min. These results indicated that ClO(2) treatment was a promising approach to preserve mulberry fruit with no significant risks of chemical residues., (Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Plants exhibit higher leaf-to-root ratios (L/R) and lower leaf nitrogen content (N(area)) in low-light than in high-light environments, but an ecological significance of this trait has not been explained from a whole-plant perspective. This study aimed to theoretically and experimentally demonstrate whether these observed L/R and N(area) are explained as optimal biomass allocation that maximize whole-plant relative growth rate (RGR). We developed a model which predicts optimal L/R and N(area) in response to nitrogen and light availability. In the model, net assimilation rate (NAR) was determined by light-photosynthesis curve, light availability measured during experiments, and leaf temperature affecting the photosynthesis and leaf dark respiration rate in high and low-light environments. Two pioneer trees, Morus bombycis and Acer buergerianum, were grown in various light and nitrogen availabilities in an experimental garden and used for parameterizing and testing the model predictions. They were grouped into four treatment groups (relative photosynthetic photon flux density, RPPFD 100% or 10%×nitrogen-rich or nitrogen-poor conditions) and grown in an experimental garden for 60 to 100 days. The model predicted that optimal L/R is higher and N(area) is lower in low-light than high-light environments when compared in the same soil nitrogen availability. Observed L/R and N(area) of the two pioneer trees were close to the predicted optimums. From the model predictions and pot experiments, we conclude that the pioneer trees, M. bombycis and A. buergerianum, regulated L/R and N(area) to maximize RGR in response to nitrogen and light availability.

Silk worm (Bombyx mori L.) larvae were fed on Mulberry leaves treated with Nux vomica mother tincture. The impact on larval, cocoon, shell and pupal weight, silk ratio, average filament length and denier, and number of breakages during reeling were investigated. The results were positive in all parameters under study except cocoon weight, pupal weight, and the average denier of the filament.

The aim of the study was to implicate the generation of reactive oxygen species (ROS) and altered cellular redox environment with the effects of Cu-deficiency or Cu-excess in mulberry (Morus alba L.) cv. Kanva 2 plants. A study of antioxidative responses, indicators of oxidative damage and cellular redox environment in Cu-deficient or Cu-excess mulberry plants was undertaken. While the young leaves of plants supplied with nil Cu showed chlorosis and necrotic scorching of laminae, the older and middle leaves of plants supplied with nil or 0.1 microM Cu showed purplish-brown pigmented interveinal areas that later turned necrotic along the apices and margins of leaves. The Cu-excess plants showed accelerated senescence of the older leaves. The Cu-deficient plants showed accumulation of hydrogen peroxide and superoxide anion radical. The accumulation of hydrogen peroxide was strikingly intense in the middle portion of trichomes on Cu-deficient leaves. Though the concentration of total ascorbate increased with the increasing supply of Cu, the ratio of the redox couple (DHA/ascorbic acid) increased in Cu-deficient or Cu-excess plants. The activities of superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), peroxidase (EC 1.11.1.7), ascorbate peroxidase (EC 1.11.1.11) and glutathione reductase (EC 1.6.4.2) increased in both Cu-deficient and Cu-excess plants. The results suggest that deficiency of Cu aggravates oxidative stress through enhanced generation of ROS and disturbed redox couple. Excess of Cu damaged roots, accelerated the rate of senescence in the older leaves, induced antioxidant responses and disturbed the cellular redox environment in the young leaves of mulberry plants.

An efficient in vitro screening method has been developed for mulberry ( Morus spp. ) to screen salinity-tolerant genotypes from a large population. Axillary buds from field-grown plants were cultured on MS medium containing five different concentrations (0.0%, 0.25%, 0.5%, 0.75% and 1.00%) of sodium chloride (NaCl) in order to study the shoot growth pattern. Rooting was also tested at four different concentrations of NaCl (0.0%, 0.1%, 0.2% and 0.3.%). NaCl has been found to inhibit the growth and development of mulberry shoots and roots in vitro. The survivability of the axillary buds of the genotypes tested was reduced from 83.7% for the controls to 6.1% in 1.0% NaCl. The average number of roots developed by the genotypes ranged from 11.9 (controls) to 0.2 (0.3% NaCl). Out of the 63 genotypes tested, only seven--Rotundiloba, English black, Kolitha-3, Berhampore-A, Kajli, BC(2)59 and C776--developed roots in 0.3% NaCl. Root growth was also reduced drastically from 1.8 cm for the controls to 0.1 cm in 0.3% NaCl. To test the reproducibility of the results in soil, five tolerant and two susceptible genotypes, identified in this in vitro study, were selected and tested under ex vitro conditions. The significant correlation coefficients obtained between the performances of these genotypes under both types of cultural conditions revealed that in vitro screening of mulberry through axillary bud culture is an easy and efficient method to identify salt-adapted genotypes within a limited space and time period.