Search Results (877)

Photosynthetic characteristics are critical for grape growth and development. Drought conditions in arid regions significantly affect these characteristics. To identify grape varieties better suited for cultivation in arid environments, this study evaluated the leaf phenotypes and photosynthetic characteristics of 27 table grape varieties in Hotan Prefecture, China. Results revealed significant variations in leaf phenotypes and chlorophyll content (SPAD) among varieties under Hotan’s drought conditions. ‘Kyoho’ exhibited the largest leaf area (254.34 cm²), while ‘Munage’ had the smallest (112.43 cm²), and ‘Manaizi’ showed the highest chlorophyll content (SPAD = 44.21). ‘Munage’ and ‘Flame Seedless’ recorded the highest net photosynthetic rates (P_Nmax = 16.24 and 16.23 μmol·m⁻²·s⁻¹, respectively), while ‘Thompson Seedless’ had the lowest respiratory loss (R_D = 1.15 μmol·m⁻²·s⁻¹) and light compensation point (I_c = 22.41 μmol·m⁻²·s⁻¹), with a highly significant positive correlation between R_D and I_c. ‘Crimson Seedless’ exhibited the highest light saturation point (I_sat = 2745.15 μmol·m⁻²·s⁻¹). Chlorophyll fluorescence analysis indicated that ‘Autumn Black’ had the highest PSII photochemical yield (F_v/F_m = 0.84), while ‘Zicuiwuhe’ showed high energy transfer indices (PI_abs = 1.78, PI_total = 1.66) and electron transfer efficiency (φ_Eo = 0.39). PIabs was significantly correlated with F_v/F_m, F_v/F_o, and energy flux parameters. ‘Molixiang’ demonstrated superior energy utilization, with the highest light absorption (ABS/CSm = 2440.8) and electron transfer flux (ETo/CSm = 874) and the lowest energy dissipation (DIo/CSm = 455.8), supported by a negative correlation between energy dissipation (DIo/CSm) and photochemical efficiency (φ_Eo). Principal component analysis revealed that ‘Molixiang’ had the highest comprehensive photosynthetic adaptability score (0.97), followed by ‘Zicuiwuhe’ (0.79) and ‘Hetianhong’ (0.73), under Hotan’s drought stress conditions. These findings provide valuable insights for selecting and breeding grape varieties adapted to arid environments and climate change. Full article

Phosphorus (P) is essential for sugarcane growth but often presents low agricultural use efficiency. This research evaluated the effects of Bacillus velezensis UFV 3918 (Bv), applied alone or with monoammonium phosphate (MAP), on sugarcane’s physiological, biochemical, and biomass variables. Six treatments were tested in a completely randomized design: absolute control (AC), commercial control (CC, full MAP dose), Bv alone, and Bv combined with 1/3, 2/3, or full MAP dose. B. velezensis (Bv) and Bv + 1/3 MAP increased soil P availability by 22%, correlating strongly with physiological, biochemical, and shoot biomass variables. These treatments boosted total chlorophyll content (11.4%), electron transport rate (28.5%), and photochemical quenching (16.9%), resulting in higher photosynthetic efficiency. Compared with CC, net CO₂ assimilation, stomatal conductance, and carboxylation efficiency increased by 49.0%, 35.4%, and 72.9%, respectively. Additionally, amino acid content and leaf acid phosphatase activity rose by 12.1% and 13.8%. Key traits associated with biomass production included stomatal density (abaxial face), chlorophyll content, electron transport rate, intercellular CO₂ concentration, and leaf acid phosphatase activity. The results highlight the potential of Bv UFV 3918, particularly with reduced MAP doses, to improve sugarcane photosynthesis and biomass accumulation, offering a sustainable and cost-effective fertilization strategy. Full article

Photosynthesis is an essential plant biological process. The performance of photosynthesis in grafted plants is affected by either the scion or the rootstock. However, the effect of the scion, rootstock and their interaction in the scion–rootstock combinations on photosynthesis of the grafted trees was not clear. In this research, the photosynthesis was analyzed within 21 citrus scion–rootstock combinations derived from three navel oranges (Citrus sinensis cv. ‘Banfield’, ‘Chislett’ and ‘Powell’) grafted on seven rootstocks [(Swingle citrumelo (C. paradisi × Poncirus trifoliata), Carrizo citrange (C. sinensis × P. trifoliata), X639 (C. reticulata × P. trifoliata), MXT (C. sinensis × P. trifoliata), Hongju (C. reticulata), Ziyang xiangcheng (C. junos) and Trifoliate orange (P. trifoliata)]. Results indicated that photosynthesis of these grafted citrus plants was significantly affected by all the scion, rootstock and their interaction. The rootstock and scion–rootstock interaction had more effect on both chlorophyll fluorescence and photosynthetic parameters with lower p values than the scion. All the scions grafted on Swingle showed the highest electron transport rate at 132.24, 158.39 and 154.59 µmol electrons m⁻² s⁻¹, and a higher net CO₂ assimilation rate at 11.22, 10.77 and 11.69 µmol m⁻² s⁻¹, respectively. The rootstock is the predominant factor affecting the content of photosynthetic pigments, and the combinations using Ziyang xiangcheng as the rootstock had the highest content at 19.83, 20.97 and 20.39 μmol s⁻¹ Kg⁻¹ FW. Electron transport rate is probably the predominant factor determining the final photosynthesis of the grafted citrus trees. This research is the first to reveal the respective effect of the scion, rootstock and their interaction on photosynthesis of citrus scion–rootstock combinations and is valuable in enhancing the understanding of the different performances in citrus scion–rootstock combinations, which aids in selecting optimal scion–rootstock combinations. Full article

Synergizing iron nutrition and rice quality is essential for the development of integrated high-quality rice. In this study, a two-year field experiment was conducted to investigate the influence of ferric oxide nanoparticles (Fe₂O₃ NPs) foliar spraying on rice yield, quality, and iron bioavailability, with spraying water as the control (CK). Our results demonstrate that Fe₂O₃ NPs foliar application increase grain yield by 1.22–3.97% for the improved filled grain rate and 1000-grain weight, essentially attributed to improved net photosynthetic rate and SPAD value after heading. In addition, Fe₂O₃ NPs application achieved a higher rate of brown rice, polished rice, and head rice, and decreased chalkiness grain rate and chalkiness degree. Rice taste value treated with Fe₂O₃ NPs application was notably increased by 2.75–9.43% compared to CK, respectively, which is also reflected in the superior breakdown value (5.85–15.18%) and inferior setback value (12.38–28.19%). Meanwhile, foliar spraying Fe₂O₃ NPs significantly increased the iron content (16.97–58.74% and 26.48–94.01%) and proportion (2.90–5.35% and 13.10–26.44%), while they decreased the molar ratio of phytate to Fe (19.70–33.67% and 31.55–45.77%) in brown rice and polished rice, increasing iron bioavailability. Our findings indicate that Fe₂O₃ NPs can be effectively applied as a foliar fertilizer to enhance rice yield, quality, and iron nutrition. Full article

Subsurface drip irrigation can improve crop water and fertilizer use efficiency, but it can cause soil hypoxia. We report on experiments performed in Aksu Prefecture, Xinjiang (41°17′ N latitude, 80°17′ E longitude), from April 2023 to October 2024 using oxygenated drip irrigation from the surface to 50 cm depth in an apple (Malus pumila Mill.) orchard, to examine the effects of drip irrigation on inter-root hypoxia, tree growth, fruit quality, and yield. Compared with surface oxygenated drip irrigation (CK), irrigating at 10 and 30 cm increased soil water content in the root system, elevated gibberellin, zeatin ribosides, and indoleacetic acid contents and reduced abscisic acid contents in new shoot tips. Compared with CK, branch and leaf nitrogen, phosphorus, and potassium contents were increased with irrigation at depths of 10 and 30 cm. The leaf nitrogen (N), phosphorus (P), and potassium (K) contents were increased by 18.03%, 22.42%, and 16.63%, respectively, in the treatment with a burial depth of 30 cm. Among treatments, irrigation at 30 cm produced the highest average daily plant water potential, and irrigation at 50 cm was the lowest. Maximum leaf soil–plant analysis development (SPAD) values occurred when irrigated at 30 cm, and minimum values occurred at 50 cm. For both years, the largest range of light flux utilization occurred when irrigated at 30 cm and the lowest when irrigated at 50 cm. Significant correlations between indoleacetic acid (IAA), total gibberellin (GA), zeatin riboside (ZRs), leaf N content, leaf K content, plant water potential (PWP), net photosynthetic rate (Pn), SPAD, and apple yield were determined by partial mantel analysis. A significant correlation was found between abscisic acid (ABA), IAA, GA, leaf P and K content, and apple quality. Principal component analysis revealed a burial depth of 30 cm had the highest principal component composite score, indicating that this burial depth, and oxygenation and fertilization regime most favored apple growth, yield, and quality. Full article

Climate change may soon impact popcorn productivity. The aim was to assess physiological and growth traits in two popcorn genotypes with different water use efficiency under water-deficit stress. The plants were grown in a greenhouse under either water stress (WS) or non-water stress (WW) conditions. Gas exchange, chlorophyll fluorescence, and leaf temperature were assessed every three days, for a total of nine measurements. At the end of the assessment period, growth traits and the SPAD index were evaluated. Our hypotheses were as follows: (a) plants of the P7 genotype (water-efficient agronomic genotype) would take longer than L65 plants (water-inefficient agronomic genotype) to reduce photosynthetic rates under water stress conditions; (b) after re-irrigation, P7 plants would recover photosynthetic capacity with values similar to the period without water stress; and (c) P7 plants would recover photosynthetic capacity faster than L65 plants when subjected to the same period of water stress. The P7 genotype (agronomic water-efficient genotype) absorbed water more quickly due to higher root biomass, root length, and root volume. Yet, at 14 days after suspending irrigation (DASI), the P7 genotype had the lowest net CO₂ assimilation rate (A_net), stomatal conductance (g_s), and transpiration rates (E) values. However, L65 (agronomic water-inefficient genotype) had the lowest A_net, g_s, and E values only at 17 DASI. As a consequence of stomatal closure in both genotypes, the E rates were reduced, and there was an increase in leaf temperature for WS plants, while L65 had higher leaf temperature at maximum water stress. No photochemical damage was detected, indicating that the reduced A_net in WS was likely due to stomatal limitations and biochemical disturbances in both genotypes. Photosynthetic recovery occurred gradually, with full restoration of rates in both genotypes at the end of the experiment. Although our initial hypothesis expected the P7 genotype to maintain photosynthesis longer under water stress, our findings showed an earlier decline in A_net compared to L65. This result is likely due to the large root system of P7 exhausting the limited soil water more rapidly in pot conditions, accelerating the onset of stress. Full article

Improving rice yield, eating quality, and zinc (Zn) nutrition is crucial to meet the growing demand for high-quality and nutritious food, while zinc itself plays a pivotal role in rice growth and quality formation. In this two-year field study, we investigated the effects of zinc oxide nanoparticles (ZnO NPs) one-time foliar application at 5, 10, and 20 mg L⁻¹ during the gestation stage on grain yield, rice quality, and zinc biofortification. Although some year-to-year variations and year × treatment interaction in the magnitude of these effects were observed, the positive responses to ZnO NPs were consistent across the two years. Results showed that ZnO NPs application increased grain yield by 1.40–4.62%, mainly supported by enhanced net photosynthetic rate and SPAD values after heading. Meanwhile, ZnO NPs significantly enhanced taste value (1.61–7.22%) and breakdown value (5.36–15.63%), while reducing chalkiness rate (5.73–18.62%), chalkiness degree (11.57–27.18%), amylose content (3.72–6.76%), and setback value (8.98–24.53%). Additionally, ZnO NPs markedly increased the zinc content (23.73–85.10% in brown rice; 29.07–103.07% in polished rice) and reduced the phytic acid to zinc molar ratio by 18.46–48.39%, improving zinc enrichment and bioavailability. These findings suggest that ZnO NPs foliar application is effective to simultaneously enhance grain productivity, rice quality, and zinc density. Full article

An appropriate drip irrigation amount and the straw return method are important ways to save water and achieve efficient maize production in semi-arid areas. A 2-year controlled field plot experiment was performed with two factors: straw return (straw removal, straw mulching) and differing drip irrigation amounts (200, 350, and 500 mm). Changes in growth, development, photosynthesis, yield, the components, and the water-use characteristics of maize under the intercropping conditions of drip irrigation amount and straw return were studied. The results showed that an increase in drip irrigation favored an increase in the net photosynthetic rate (P_n), stomatal conductance (G_s), and intercellular carbon dioxide concentration (C_i) of maize, and promoted an increase in maize plant height and leaf area index, which resulted in the accumulation of more dry matter and increased the maize yield. Compared with straw removal, straw mulching maintained a higher photosynthetic capacity at the later stages of maize growth and development under irrigations of 200 and 350 mm; the average increase in P_n over two years ranged from 4.06 to 19.19%; and good plant growth was maintained, thereby leading to the accumulation of more dry matter, with the average increase over two years ranging from 0.51 to 27.22%. Straw mulching also significantly improved water-use efficiency (WUE) at 350 mm of irrigation, with the average increase in yield over two years ranging from 4.58 to 4.83%. Overall, straw mulching had a positive impact on maize when irrigation was low, and when it was high, straw mulching did not adversely affect maize. Therefore, irrigation combined with straw mulching technology may be used to improve maize yield and WUE in semi-arid areas of Jilin Province. Full article

To explore the mechanisms by which water, fertilizers, and dissolved oxygen affect the physiological growth and yield quality of custard apple, this study aims to optimize water–fertilizer–oxygen coupling regulation schemes for custard apple in dry hot valley regions through a multi-level fuzzy evaluation method, thereby addressing issues such as soil compaction and reduced aeration caused by long-term water and fertilizer drip irrigation. The experiment was conducted on custard apple in a dry, hot valley area, employing orthogonal and quadratic regression-orthogonal designs. Three factors were set at multiple levels: irrigation amount (60–100% ETc), fertilization rate (1500–1900 kg·ha⁻¹), and dissolved oxygen concentration (6–10 mg·L⁻¹). Custard apple development, production, and attributes were assessed. The two-year trial from 2023 to 2024 demonstrated that the new shoots, leaf area, and net photosynthetic rate of plants treated with W3F2O1 (100% ETc, 1700 kg·ha⁻¹ fertilization rate, and high oxygen 6 mg·L⁻¹) and W3F3O2 (100% ETC, 1500 kg·ha⁻¹ fertilization rate, and high oxygen 8 mg·L⁻¹) were significantly superior to those of W1F1O1 (60% ETc, 1900 kg·ha⁻¹ fertilization rate, and high oxygen 6 mg·L⁻¹), with a single-plant yield of 10.31 kg, and increases in diameter and length of 31.6% and 27.6%, respectively (p < 0.05); quality indicators were also optimal under W3F3O2 (100% ETC, 1500 kg·ha⁻¹ fertilization rate, and high oxygen 8 mg·L⁻¹) treatment, with soluble sugar and vitamin C levels increasing by 17.3% and 29.9%, respectively, compared to the control. Using a multi-level fuzzy evaluation to comprehensively evaluate the water–fertilizer–oxygen coupling, the comprehensive productivity of custard apples was significantly improved by optimizing the root zone microenvironment. It is recommended that dry hot valleys adopt an optimized range of 82.5–100% ETc irrigation, 1650–1847.86 kg·ha⁻¹ fertilization, and 7.4–9.25 mg·L⁻¹ dissolved oxygen, providing a theoretical basis for precise irrigation and sustainable cultivation of tropical fruit trees. Full article

In recent years, high temperature and drought have severely impacted the growth and development of loquat [Eriobotrya japonica (Thunb.) Lindl.] plants. Although dopamine can improve the stress resistance of plants, its role in combined stress requires further exploration. This study investigated the alleviative effect and mechanism of exogenous dopamine on loquat seedlings subjected to the combined stress of high temperature and drought. The combined stress significantly reduced root viability, photosynthetic pigment content, and net photosynthetic rate (Pn) while markedly increasing reactive oxygen species (ROS) levels, thiobarbituric acid-reactive substances (TBARS) content, and electrolyte leakage (EL). The seedlings exhibited pronounced wilting symptoms, along with markedly reduced root surface area and volume. Dopamine treatment significantly alleviated combined stress-induced damage. This mitigation was manifested through substantially enhanced root viability, photosynthetic pigment content, Pn, antioxidant enzyme activities, and osmotic adjustment substances concomitantly with marked reductions in ROS, TBARS content, and EL. Dopamine significantly reduced seedling wilting severity and improved root morphological parameters. This study demonstrates that dopamine enhances loquat seedlings’ tolerance to combined stress through coordinated mechanisms: maintaining photosynthetic pigments and improving stomatal conductance to sustain photosynthetic efficiency, enhancing antioxidant enzyme activity and ROS scavenging capacity to mitigate oxidative damage, and promoting osmotic solute accumulation for osmotic potential regulation. Full article

Drought stress is one of the key abiotic stress factors limiting the growth and development, yield formation, and improvement in the quality of jackfruit (Artocarpus heterophyllus). However, systematic evaluations of drought tolerance in jackfruit germplasm resources remain limited. In this study, six jackfruit cultivars were used as materials. By systematically comparing 26 indicators, including leaf structural characteristics, chlorophyll concentration, and photosynthetic parameters, the primary evaluation indicators for jackfruit drought tolerance were identified, and clear microscopic structural images of leaves from different jackfruit cultivars were obtained. In this study, significant differences were observed among different jackfruit germplasm resources in terms of leaf structure, chlorophyll concentration, and photosynthetic characteristics. Comprehensive analysis identified A. ‘Changyou’ as the jackfruit cultivar with the highest drought tolerance score and A. ‘Siji’ as the variety with the lowest drought tolerance score. By establishing a systematic evaluation system for jackfruit drought tolerance, it was found that jackfruit cultivars with high drought tolerance had significantly thicker palisade parenchyma than other cultivars, a rougher leaf epidermis, and more densely distributed stomata on the leaves, while their chlorophyll concentration was significantly lower than that of cultivars with lower drought tolerance scores. Jackfruit cultivars with the lowest drought resistance scores had significantly lower net photosynthetic rates, transpiration rates, stomatal conductance, and light saturation points than other cultivars. This study’s results established a drought resistance evaluation system for jackfruit germplasm resources, providing theoretical support for the selection and breeding of high-drought-resistant superior jackfruit cultivars. Full article

Silicon plays a positive role in plant growth and physiological activities; however, silicon fertilizer application in bamboo remains limited. This study explored the silicon accumulation and photosynthetic capacity of Dendrocalamus brandisii in response to sodium silicate (SS) foliar application across vegetative phenological stages. The results showed that August (shooting stage) and May (branching and leafing stage) were the critical periods for silicon accumulation. SS significantly enhanced the net photosynthetic rate (Pn), chlorophyll content, and photosystem activity (Fv/Fm, Fv′/Fm′), particularly in August and May. Correlation analysis revealed that silicon content was significantly positively correlated with photosynthetic parameters (Pn, chlorophyll a/b) and photoassimilate accumulation (soluble sugar, starch), confirming that silicon optimized leaf light capture and carbon assimilation capacity by promoting phytolith formation. This research provides a theoretical foundation for the application of silicon fertilizers in bamboo forest cultivation. Full article

Liriope muscari is a medicinal and ornamental herbaceous plant with significant economic value, as its tuberous roots are used for medicinal purposes. However, the current production of medicinal plants is characterized by wasteful use of resources and ecological risks caused by the unreasonable application of nitrogen fertilizers. In this study, based on uniform application of phosphorus and potassium fertilizers, six nitrogen application levels were set in pot experiments (expressed as N): N0: 0 kg/ha, N1: 208.33 kg/ha, N2: 416.66 kg/ha, N3: 625 kg/ha, N4: 833.33 kg/ha, N5: 1041.66 kg/ha). The morphological characteristics, photosynthetic physiology, tuber yield and quality, and seven nitrogen fertilizer utilization indices of L. muscari were analyzed and measured. Correlation analysis and structural equation modeling (SEM) were employed to investigate the mechanism by which nitrogen influences its growth and development, photosynthetic characteristics, tuber yield and quality, and nitrogen fertilizer utilization efficiency. The results showed that (1) nitrogen significantly promoted plant height, crown width, tiller number, and chlorophyll synthesis, with the N3 treatment (625 kg/ha) reaching the peak value, and the crown width and tiller number increasing by 26.44% and 38.90% compared to N0; the total chlorophyll content and net photosynthetic rate increased by 39.67% and 77.04%, respectively, compared to N0; high nitrogen (N5) inhibited photosynthesis and increased intercellular CO₂ concentration; (2) Fresh weight of tuberous roots, polysaccharide content, and saponin C content peaked at N3 (34.67 g/plant, 39.89%, and 0.21%), respectively, representing increases of 128.69%, 28.37%, and 33.66% compared to N0; (3) Nitrogen uptake, nitrogen fertilizer utilization efficiency, agronomic utilization efficiency, and apparent utilization efficiency were optimal at N3, while high nitrogen (N4–N5) reduced nitrogen fertilizer efficiency by 40–60%; (4) SEM analysis indicated that tiller number and transpiration rate directly drive yield, while stomatal conductance regulates saponin C synthesis. Under the experimental conditions, 625 kg/ha is the optimal nitrogen application rate balancing yield, quality, and nitrogen efficiency. Excessive nitrogen application (>833 kg/ha) induces photosynthetic inhibition and “luxury absorption”, leading to source-sink imbalance and reduced accumulation of secondary metabolites. This study provides a theoretical basis and technical support for the precise management of nitrogen in Liriope-type medicinal plants. It is expected to alleviate the contradictions of “high input, low output, and heavy pollution” in traditional fertilization models. Full article

Tomato fruit (Solanum lycopersicum) is a valuable agricultural crop worldwide due to its nutritional value and culinary applications, making it one of the most widely consumed vegetables in the human diet. However, excessive solar UV-B radiation represents a significant factor in decreasing productivity, marketable yields, and fruit quality in tomato crops by causing damage to both DNA and the photosynthetic system, as well as chlorophyll degradation. The application of silicon nanoparticles has been shown to increase tolerance to abiotic stressors, including enhanced UV-B radiation. Therefore, this study aims to evaluate the protective effects of foliar silicon nanoparticle (SiNP) application on photosynthetic parameters, photosynthetic pigments, and secondary metabolites under enhanced UV-B stress in tomato plants. Photosynthetic parameters (stomatal conductance to water vapor, net CO₂ assimilation rate, transpiration rate, and intercellular CO₂ molar fraction), biogenic volatile organic compounds (BVOCs), chlorophylls, and carotenoids were evaluated. The application of SiNPs showed beneficial effects on plants grown under ambient UV-B conditions, increasing photosynthetic parameters while also enhancing chlorophyll and carotenoid levels. In plants exposed to enhanced UV-B radiation, SiNP treatment helped to maintain and even improve photosynthetic parameters and stomatal function in leaves while also promoting the accumulation of photosynthetic pigments. Additionally, the application of SiNPs also resulted in a slightly higher content of lycopene and total carotenoids in tomato fruits. Full article

Using multiple species in native plant communities may improve control efficiency compared with single-species use. We conducted field investigations to assess the effects of Artemisia argyi, Portulaca oleracea, and their mixtures on the growth and reproduction of Mikania micrantha, followed by a greenhouse de Wit replacement series to compare different combinations of M. micrantha, A. argyi, and P. oleracea in terms of multispecies competition, phytoallelopathy, and photosynthesis. Field investigation showed that compared with M. micrantha monoculture (Group D), aboveground biomass, total stem length, flower biomass, inflorescence biomass, seed biomass, and seed number of M. micrantha increased in the P. oleracea community (Group B), though only seed number was significantly higher (p < 0.05). In contrast, in the A. argyi community (Group A) and the mixed community of A. argyi and P. oleracea (Group C), all these indicators decreased significantly (p < 0.05), in the order: Group C < Group A < Group D < Group B. This indicates that the mixed community (Group C) most strongly suppressed M. micrantha growth and reproduction. The effects of A. argyi, P. oleracea, and their mixture on the growth of M. micrantha in the greenhouse experiments mirrored the trends observed in field investigations. Calculated indices (relative yield, relative yield total, competitive balance index, and change in contribution) of A. argyi, P. oleracea, and their mixed population on M. micrantha demonstrated a higher competitive ability and higher influence of the combination of the two species compared with either A. argyi or P. oleracea alone. The interspecific phytoallelopathy experiment demonstrated strong allelopathic potential of A. argyi versus M. micrantha (p < 0.05) but showed no significant effect on P. oleracea. The net photosynthetic rate (Pn) of M. micrantha was generally lower in communities with both competitors compared with single-species communities. Our results suggest that, compared with a single plant population, the mixed population of A. argyi and P. oleracea exhibited a markedly enhanced ecological control capability through increased relative competitive ability, strengthened allelopathic inhibition, and markedly reduced photosynthetic efficiency of M. micrantha. Full article