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971.
972.
Deng Chen Muhammad Kamran Shen Chen Junjie Xing Zhiguang Qu Caiyun Liu Zhiyong Ren Xuan Cai Xiao-Lin Chen Jingbo Xu 《Molecular Plant Pathology》2023,24(4):374-390
Cell wall polysaccharides play key roles in fungal development, virulence, and resistance to the plant immune system, and are synthesized from many nucleotide sugars in the endoplasmic reticulum (ER)-Golgi secretory system. Nucleotide sugar transporters (NSTs) are responsible for transporting cytosolic-derived nucleotide sugars to the ER lumen for processing, but their roles in plant-pathogenic fungi remain to be revealed. Here, we identified two important NSTs, NST1 and NST2, in the rice blast fungus Magnaporthe oryzae. Both NSTs were localized in the ER, which was consistent with a function in transporting nucleotide sugar for processing in the ER. Sugar transport property analysis suggested that NST1 is involved in transportation of mannose and glucose, while NST2 is only responsible for mannose transportation. Accordingly, deletion of NSTs resulted in a significant decrease in corresponding soluble saccharides abundance and defect in sugar utilization. Moreover, both NSTs played important roles in cell wall integrity, were involved in asexual development, and were required for full virulence. The NST mutants exhibited decreasing external glycoproteins and exposure of inner chitin, which resulted in activation of the host defence response. Altogether, our results revealed that two sugar transporters are required for fungal cell wall polysaccharides accumulation and full virulence of M. oryzae. 相似文献
973.
Jameel M. Al-Khayri Salha M. Alshamrani Adel A. Rezk Wael F. Shehata Mustafa I. Almaghasla Tarek A. Shalaby Ahmed M. Saad Fatmah A. Safhi Muhammad N. Sattar Arafat A. Abdel Latef Mahmoud Z. Sitohy Abdallah A. Hassanin 《Phyton》2023,92(5):1493-1512
Appropriate knowledge of the parental cultivars is a pre-requisite for a successful breeding program. This study
characterized fruit yield, quality attributes, and molecular variations of ten tomato cultivars during three consecutive generations under greenhouse conditions. Peto 86, Castle Rock, and Red Star cultivars showed the highest
fruit yield (kg/plant), total phenolic compounds (TPC), and sap acidity. Principal component analysis categorized
the evaluated fruit yield into three groups based on their quality attributes. A robust positive correlation appeared
among traits inside each group. A positive correlation was likewise noticed between the first and the second
groups. However, a negative correlation was detected between the first, the second and the third group. Molecular
profiling, using seven inter-simple sequence repeat (ISSR) primers, produced 60 loci, including 49 polymorphic
loci. The molecular analysis also pinpointed the highest genetic similarity (0.92) between P73 and Moneymaker,
while the lowest genetic similarity (0.46) was observed between Castle Rock and Moneymaker. The cultivars
P73 and Moneymaker showed the lowest genetic distance (2.24), while the highest genetic distance (5.92) was
observed between Super Marmand and Peto86, on the one hand, and between Castle Rock and Moneymaker,
on the other hand. The chemical analysis of fruit sap indicated the highest levels of TPC, total flavonoids, anthocyanin, ascorbic acid and total soluble solids in Peto 86 and Castle Rock cultivars. Phylogeny analysis of tomato
cultivars based on morphological and molecular attributes indicated four distinct clades. Peto 86, Castle Rock, and Red star cultivars can be recommended for the tomato hybridization breeding programs in the future, with other
tomato cultivars as potentially high-yielding parents. 相似文献
974.
Talha Ali Chohan Tahir Ali Chohan Muhammad Zahid Mumtaz Muhammad Waqar Alam Salah ud Din Iqra Naseer Ayesha Riaz Tayyeba Naseem Areeba Iftikhar Dur E. Najaf Ali Mubashir Hassan Hayssam M. Ali 《Phyton》2023,92(7):1943-1954
Myzus persicae (M. persicae) is now considered a threat to agricultural crops due to economic losses. Numerous synthetic insecticides applied every year against M. persicae, are reported to be unsafe for environment, humans, and beneficial insects. Furthermore, several species of Myzus have been found to develop resistance due to over application of these insecticides. Therefore, it is required to find some novel insecticide that would be safe for the environment as well as for humans. In the current study, two major pure constituents α-pinene and β-caryophyllene were evaluated for their insecticidal potential against M. persicae using a fumigant toxicity assay. Furthermore, impact of α-pinene and β-caryophyllene on expression of five different genes, e.g., HSP 60, FPPS I, OSD, TOL and ANT responsible for reproduction, dispersion, and growth of M. persicae has also been investigated. To perform fumigant toxicity assay, five different concentrations (3.5, 4, 4.5, 5 and 6 μL L−1) of α-pinene and β-caryophyllene were prepared. Lethal concentration (LC) was calculated, and gene expression studies were executed through qRT PCR at LC30 of α-pinene and β-caryophyllene. Both constituents demonstrated excellent fumigant toxicity effects against M. persicae at all five concentrations. However, α-pinene shows significantly better results (98%) as compared to β-caryophyllene (80%) after 72 h at 6 μL L−1 of dose. The highest upregulation in expression was demonstrated at LC30 dose of α-pinene in five in three out of five genes understudy (TOL, ANT, and FPPS I). Conversely, two genes HSP 60 and OSD demonstrated downregulation at LC30 dose of β-caryophyllene. Conclusively, our results highlighted the promising insecticidal potential of both compounds α-pinene and β-caryophylleneby interfering with the reproduction and development related processes in M. persicae, allowing us to recommend the phytoconstituents under investigation as an ecofriendly alternative to synthetic insecticides. 相似文献
975.
Fazal Hina Akram Muhammad Ahmad Nisar Qaisar Muhammad Kanwal Farina Rehman Gohar Ullah Irfan 《Protoplasma》2023,260(2):557-570
Protoplasma - The Mentha species of family Lamiaceae are famous for their flavor and are commercially used in many food products worldwide. They are widely used to cure digestive problems as well... 相似文献
976.
Yurong Jiang Muhammad Yasir Yuefen Cao Lejia Hu Tongli Yan Shuijin Zhu Guoquan Lu 《Phyton》2023,92(2):399-410
Cultivating salt-tolerant crops is a feasible way to effectively utilize saline-alkali land and solve the problem of
underutilization of saline soils. Quinoa, a protein-comprehensive cereal in the plant kingdom, is an exceptional
crop in terms of salt stress tolerance level. It seems an excellent model for the exploration of salt-tolerance
mechanisms and cultivation of salt-tolerant germplasms. In this study, the seeds and seedlings of the quinoa cultivar Shelly were treated with different concentrations of NaCl solution. The physiological, biochemical characteristics and agronomic traits were investigated, and the response patterns of three salt stress-responsive genes
(SSRGs) in quinoa were determined by real-time PCR. The optimum level of stress tolerance of quinoa cultivar
Shelly was found in the range of 250–350 mM concentration of NaCl. Salt stress significantly induced expression
of superoxide dismutase (SOD), peroxidase (POD), and particularly betaine aldehyde dehydrogenase (BADH).
BADH was discovered to be more sensitive to salt stress and played an important role in the salt stress tolerance
of quinoa seedlings, particularly at high NaCl concentrations, as it displayed upregulation until 24 h under
100 mM salt treatment. Moreover, it showed upregulation until 12 h under 250 mM salt stress. Taken together,
these results suggest that BADH played an essential role in the salt-tolerance mechanism of quinoa. Based on the
expression level and prompt response induced by NaCl, we suggest that the BADH can be considered as a molecular marker for screening salt-tolerant quinoa germplasm at the early stages of crop development. Salt treatment
at different plant ontogeny or at different concentrations had a significant impact on quinoa growth. Therefore,
an appropriate treatment approach needs to be chosen rationally in the process of screening salt-tolerant quinoa
germplasm, which is useful to the utilization of saline soils. Our study provides a fundamental information to
deepen knowledge of the salt tolerance mechanism of quinoa for the development of salt-tolerant germplasm
in crop breeding programs. 相似文献
977.
Muhammad Asad Rashad Rasool Khan Ahmed B. Aljuboory Muhammad Haroon U. Rashid Uttam Kumar Inzamam Ul Haq Aqsa Hafeez Ahmed Noureldeen Khadiga Alharbi 《Phyton》2023,92(4):1161-1172
The beet armyworm (BAW), Spodoptera exigua (Lepidoptera: Noctuidae) is a highly destructive pest of vegetables and
field crops. Management of beet armyworm primarily relies on synthetic pesticides, which is threatening the beneficial
community and environment. Most importantly, the BAW developed resistance to synthetic pesticides with making it
difficult to manage. Therefore, alternative and environment-friendly pest management tactics are urgently required.
The use of pesticidal plant extracts provides an effective way for a sustainable pest management program. To evaluate
the use of pesticidal plant extracts against BAW, we selected six plant species (Lantana camara, Aloe vera, Azadirachta
indica, Cymbopogon citratus, Nicotianatabacum, and Ocimum basilicum) for initial screening experiment. Four out of
six plant species such as A. indica, N. tabacum, C. citratus and O. basilicum showed promising mortality of more than
50%. Therefore, we selected these four plant extracts for the subsequent experiments. Through contact bioassay, A.
indica showed high mortality 66.63%, followed by the N. tabacum 53.33%, at 10% w/v concentration. Similarly, N.
tabacum showed the highest mortality rate, 66% at 10% w/v concentration, followed by the A. indica 46% through
feeding bioassay. Furthermore, the feeding deterrence assay showed that C. citratus had a high antifeedant index
(−50) followed by A. indica (−39), and N. tabacum (−28). In living plant assay, the N. tabacum extract showed a
low mean damage score 3.6 on living cotton plant followed by C. citratus 4.5 and A. indica 5.5. Hence, extracts of
three plant species provided promising results against the BAW, which can minimize the use of synthetic chemicals,
particularly for small landholding farmers. Further studies are also required to evaluate the effects of these plant extract
against BAW on cotton plants under field conditions to optimize the further use. 相似文献
978.
Bovine pancreatic trypsin was crystallized, in-complex with Lima bean trypsin inhibitor (LBTI) (Phaseolus lunatus L.), in the form of a ternary complex. LBTI is a Bowman–Birk-type bifunctional serine protease inhibitor, which has two independent inhibitory loops. Both of the loops can inhibit trypsin, however, only the hydrophobic loop is specific for inhibiting chymotrypsin. The structure of trypsin incomplex with the LBTI has been solved and refined at 2.25 Å resolution, in the space group P41, with Rwork/Rfree values of 18.1/23.3. The two binding sites of LBTI differ in only two amino acids. Lysine and leucine are the key residues of the two different binding loops positioned at the P1, and involved in binding the S1 binding site of trypsin. The asymmetric unit cell contains two molecules of trypsin and one molecule of LBTI. The key interactions include hydrogen bonds between LBTI and active site residues of trypsin. The 3D structure of the enzyme–inhibitor complex provided details insight into the trypsin inhibition by LBTI. To the best of our knowledge, this is the first report on the structure of trypsin incomplex with LBTI. 相似文献
979.
Muhammad Arshad Altaf Hussain Muhammad Javed William T. Frankenberger Jr. 《Plant and Soil》1993,148(1):129-135
A pot experiment was conducted to evaluate the influence of an ethylene (C2H4) precursor, L-methionine (L-MET) added to soil on the growth, nodulation and chemical composition of a leguminous tree,Albizia lebbeck L. Benth (black ciris). L-Methionine (10-9 to 10-1 gkg-1 soil) was applied as a soil drench to established uniform seedlings ofAlbizia lebbeck L. L-MET treatments had significant effects on all the plant growth parameters monitored. Plants responded positively to low to medium L-MET concentrations (10-9 to 10-3 gkg-1 soil) while high levels of L-MET had either negative or no effects. An L-MET treatment of 10-6 gkg-1 soil was the most effective in increasing shoot height, plant girth, dry weights of shoot and roots, number and dry weight of nodules and total biomass. The chemical analysis of the plant material revealed that the highest N, P and K contents were present in plants exposed to 10-6 gL-MET kg-1 soil, while Ca and Mg contents were maximum with 10-5 g L-MET kg-1 soil. A similar trend was observed with the uptake of these elements by the plant. A significant quadratic dose-response relationship was found in all cases when each individual parameter was regressed against log [L-MET] excluding the control. Since, attempts were made to prevent any nutritional and water stress, the plant response to L-MET was most likely caused by substrate-dependent microbial production of ethylene in the rhizosphere. ei]A C Borstlap 相似文献
980.
Khair Un Nisa Attiq Ur Rehman Kakar Muhammad Asghar Samiullah Naqeebullah Niamatullah Arif Shah 《Luminescence》2023,38(5):647-661
A flow injection (FI) methodology using the acidic potassium permanganate (KMnO4)–rhodamine-B (Rh-B) reaction with chemiluminescence (CL) detection was established to determine acetochlor and cartap-HCl pesticides in freshwater samples. Experimental parameters were optimized, and Chelex-100 cationic exchanger mini column and solid-phase extraction (SPE) were used as phase separation techniques. Linear calibration curves were observed for the standard solutions of acetochlor and cartap-HCl over the ranges 0.005–2.0 mg L−1 [y = 1155.8x + 57.551, R2 = 0.9999 (n = 8)] and 0.005–1.0 mg L−1 [y = 979.76x + 14.491, R2 = 0.9998 (n = 8)] with LODs and LOQs of 7.5 × 10−4 and 8.0 × 10−4 mg L−1 (3σ blank) and 2.5 × 10−3 and 2.7 × 10−3 mg L−1 (10σ blank), respectively, with an injection throughput of 140 h−1. These methods were used to estimate acetochlor and cartap-HCl with or without the SPE procedure, respectively, in spiked freshwater samples. Results obtained were not significantly different at a 95% confidence level to those of other reported methods. Recoveries for acetochlor and cartap-HCl were obtained over the ranges 93–112% (RSD = 1.9–3.6%) and 98–109% (RSD = 1.7–3.8%), respectively. The most probable CL reaction mechanism was explored. 相似文献