This study evaluated the morphological and physiological traits of 29 lanzones (Lansium domesticum) accessions from four varieties: ‘Longkong’, ‘Duku’, ‘Mindanao’, and ‘Paete’. Most accessions exhibited verticillate and irregular branching, except ‘Longkong 3’, ‘Longkong 4’, and ‘Mindanao 1’, which showed pyramidal forms. All accessions had elliptic leaflets with broadly acuminate tips and cuneate bases, though leaflet size and area varied due to environmental factors such as light, soil type, and water availability. ‘Longkong’ accessions had the highest chlorophyll content, indicating greater photosynthetic efficiency and growth potential. In fruit morphology, ‘Duku’ produced the heaviest bunches, while ‘Longkong’ had more compact clusters. Taste differences were also observed, with ‘Paete’ being sweet to sour while ‘Longkong’ and ‘Duku’ mainly sweet. Significant variation occurred in fruit size, weight, peel thickness, aril characteristics, seed number, and total soluble solids. These variations are influenced by both genetic and environmental factors, including parthenocarpy, apomixis, and natural hybridization. While vegetative traits were mostly similar, differences in physiological and fruit traits provide essential information for cultivar improvement and enhanced lanzones production.

ABSTRACT: Hops are grown mainly for the brewing market due to the rich chemical composition that gives beer aroma and bitterness. Brazil is one of the largest beer producers and consumers in the world and one of the largest hop importers. There is growing demand and interest in producing hops for domestic supply; however, as this crop originates from a temperate climate and the Northern Hemisphere, it is important to carry out research that describes the development of hops in a tropical climate to provide information on its cultivation in Brazil, as well as to determine its behavior in organic cultivation. A randomized block design was adopted, the treatments consisted of two cropping systems, conventional and organic, for Hallertau Mittelfrueh variety cultivation, with four blocks and three plants per plot. Gas exchange analyzes of plants under both cultivation systems were performed to obtain measurements of A, g s , Ci, E, WUE and A/Ci, morphometric and yield analyzes were also carried out. In comparison with the plants of the organic system, the plants of the conventional cultivation had greater photosynthetic efficiency; however, the practices adopted in the organic cultivation system provided the plants with greater productive capacity.

Abstract The objective of this review is to interpret the usage of alternative renewable systems that is imperative for future developments on a global industrial scale. Microalgae have appeared as the most realistic source for biofuel generation due to the accumulation of lipids in most of the strains with rapid biomass expansion and greater photosynthetic efficiency than land plants. Microalgal‐derived feedstocks have a broad range of commercial advantages and can be used as promising renewable fuel substitutes with zero net CO2 emission. Important facets of algal‐based biofuel production, growing and harvesting techniques, approaches to thermochemical conversion, synthesis of commodities with added value, and recent breakthroughs in the field of synthetic biology for fuel production are covered.

The apple rootstock Malus prunifolia (Willd.) Borkh. is widely used for apple production. Because polyploid plants are often more tolerant to abiotic stress than diploids, we wondered whether polyploidy induction in M. prunifolia might improve its stress tolerance, particularly to high salinity. We used a combination of colchicine and dimethyl sulfoxide (DMSO) to induce chromosome doubling in M. prunifolia and identified the resulting polyploids by stomatal observations and flow cytometry. We found the best way to induce polyploidy in M. prunifolia was to use 2% DMSO and 0.05% colchicine for 2days for leaves or 0.02% colchicine for stem segments. The results of hydroponic salt treatment showed that polyploid plants were more salt tolerant and had greater photosynthetic efficiency, thicker leaf epidermis and palisade tissues, and shorter but denser root systems than diploids. During salt stress, the polyploid leaves and roots accumulated less Na+, showed upregulated expression of three salt overly sensitive (SOS) pathway genes, and produced fewer reactive oxygen species. The polyploid plants also had considerably higher ABA and jasmonic acid levels than diploid plants under salt stress. Under normal growth conditions, gibberellins (GAs) levels were much lower in polyploid leaves than in diploid leaves; however, after salt treatment, polyploid leaves showed upregulation of essential GAs synthesis genes. In summary, we developed a system for the induction of polyploidy in M. prunifolia and response to salt stress of the resulting polyploids, as reflected in leaf and root morphology, changes in Na+ accumulation, antioxidant capacity and plant hormone levels.

Cotton productivity depends on solar radiation reaching to the ground. Therefore, the present laboratory and field experiments were conducted during 2018-2019 growing seasons at the experimental station of Tashkent State Agrarian University, Uzbekistan to study UVA supplementations on growth parameters of cotton indoor and open field cultivations. Cotton (Gossipium hirsutum L. cv. “S-6524”) seeds were exposed to different doses of UV-A radiation at 340-350 nm wavelengths under a constant irradiance of 1.6 W/m2. The highest germination value (86.3%) was observed in the UVA treatment for 10 minutes. In the field condition, 10 μmol/m2/s UVA radiation intensities were given to the seeds before planting and at the true leaf formation, budding, and flowering stages of cotton, coded as UVA-2 toUVA-5 treatments. The seed germination rate was increased by 15.5% in the UVA-2 treatmentcompared to the untreated control. Furthermore, the supplemental UV-A radiation increasedoverall biomass production by 6.3 (UVA-2); 8.9 (UVA-3) and 15.1% (UVA-4), which correlated with 3.7%; 5.6% and 7.4% greater photosynthetic efficiency than those in control. All these positive changes due to the UVA intensities reflected to the cotton yields as indicated by greater values up to 10.9%, 12.3% and 15.1% in the UVA-2, UVA-3 and UVA-4 treatments, respectively. Taken together, the tested UVA supplementations enhanced the seed germination of indoor cultivation and stimulated cotton development processes of in the field condition.

Under abiotic stress conditions, arbuscular mycorrhizal (AM) fungi help plants by improving nutrient and water uptake. Finger millet (Eleusine coracana L.) is an arid crop having soils with poor water holding capacity. Therefore, it is difficult for the plants to obtain water and mineral nutrients from such soil to sustain life. To understand the role of mycorrhizal symbiosis in water and mineral up-take from the soil, we studied the role of Rhizophagus intraradices colonization and its beneficial role for drought stress tolerance in finger millet seedlings. Under severe drought stress condition, AM inoculation led to the significant increase in plant growth (7 %), phosphorus and chlorophyll content (29 %). Also, under drought stress the level of osmolytes such as proline and soluble sugars were found to be increased in AM inoculated seedlings. Under water stress, the lipid peroxidation in leaves of mycorrhized seedlings was reduced by 29 %. The flavonoid content of roots in AM colonized seedlings was found 16 % higher compared to the control, whereas the leaves were accumulated more phenol. Compared to the control, ascorbate level was found to be 25 % higher in leaf tissue of AM inoculated seedlings. Moreover, glutathione (GSH) level was also increased in mycorrhiza inoculated seedlings with a maximum increment of 182 % under severe stress. The results demonstrated that AM provided drought tolerance to the finger millet seedlings through a stronger root system, greater photosynthetic efficiency, a more efficient antioxidant system and improved osmoregulation.

Leaf functional traits at home and abroad: A community perspective of sycamore maple invasion

A R2R3-MYB transcription factor gene, FtMYB13, from Tartary buckwheat improves salt/drought tolerance in Arabidopsis

Tissue and skeletal changes in the scleractinian coral Stylophora pistillata Esper 1797 under phosphate enrichment

The Brazilian National Program for Biofuel Production has been encouraging diversification of feedstock for biofuel production. One of the most promising alternatives is the use of microalgae biomass for biofuel production. The cultivation of microalgae is conducted in aquatic systems, therefore microalgae oil production does not compete with agricultural land. Microalgae have greater photosynthetic efficiency than higher plants and are efficient fixing CO2. The challenge is to reduce production costs, which can be minimized by increasing productivity and oil biomass. Aiming to increase the production of microalgae biomass, mixotrophic cultivation, with the addition of glycerol has been shown to be very promising. During the production of biodiesel from microalgae there is availability of glycerol as a side product of the transesterification reaction, which could be used as organic carbon source for microalgae mixotrophic growth, resulting in increased biomass productivity. In this paper, to study the effect of glycerol in experimental conditions, the batch culture of the diatom Phaeodactylum tricornutum was performed in a 2-liter flask in a temperature and light intensity controlled room. During 16 days of cultivation, the number of cells per ml was counted periodically in a Neubauer chamber. The calculation of dry biomass in the control experiment (without glycerol) was performed every two days by vacuum filtration. In the dry biomass mixotrophic experiment with glycerol concentration of 1.5 M, the number of cells was assessed similarly in the 10th and 14th days of cultivation. Through a volume element methodology, a mathematical model was written to calculate the microalgae growth rate. Was used an equation that describes the influence of irradiation and concentration of nutrients in the growth of microalgae. A simulation time of 16 days was used in the computations, with initial concentration of 0.1 g l-1. In order to compare simulation data with experimental data, we calculated the dry weight in 8 points in the course of sixteen days. In this way, it was possible to assess graphically biomass concentration versus time through the experiments and by numerical simulation. It was identified that the simulation results were consistent with the experiments and that the addition of glycerol greatly influenced the growth of microalgae. In the present analysis, the glycerol added increased 30% in biomass.

Global carbon cycle assessments of anthropogenic nitrogen (N) deposition influences on carbon sequestration often assume enhanced sequestration results. This assumption was evaluated at a Rocky Mountains spruce-fir forest. Forest canopy N uptake (CNU) of atmospheric N deposition was estimated by combining event wet and throughfall N fluxes with gradient measured HNO3 and NH3 as well as inferred (NOx and particulate N) dry fluxes. Approximately 80% of the growing-season 3 kgN ha.1 total deposition is retained in canopy foliage and branches. This CNU constitutes ~ 1/3 of canopy growing season new N supply at this conifer forest site.Daytime net ecosystem exchange (NEE) significantly (P = 0.006) and negatively (CO2 uptake) correlated with CNU. Multiple regression indicates ~20% of daytime NEE may be attributed to CNU (P >0.02); more than soil water content. A wet deposition N-amendment study (Tomaszewski and Sievering-part II), at canopy spruce branches, increased their growing-season CNU by 40-50% above ambient. Fluorometry and gas exchange results show N-amended spruce branches had greater photosynthetic efficiency and higher carboxylation rates than control and untreated branches. Namended branches had 25% less photoinhibition, with a 5-9% greater proportion of foliar-N-in-Rubisco. The combined results provide, partly, a mechanistic explanation for the NEE dependence on CNU.

Prokaryotic energy and nutrient cycling is critical to coral reef ecosystems. Living coral surfaces can harbour diverse but markedly different bacterial communities than other marine surfaces and, these communities may alter considerably following a disturbance. The consequences of these changes may include; alteration of fluxes and routes of organic and inorganic matter cycling, accelerated eutrophication and proliferation of algal blooms, all of which may ultimately lead to changes in trophic interactions. Coral reefs worldwide are experiencing a decline in health of a magnitude not seen in recorded history. In view of current trends and events over the last 30 years, it appears inevitable that we will lose a large percentage of living coral in the coming decades. It is therefore necessary to gain a greater understanding of the consequences associated with a substantial increase in the area of dead coral substratum. In particular the changes in the bacterial associates of coral surfaces following mortality may lead to dramatic changes in carbon and nutrient cycling, which may have implications throughout the ecosystem. This study investigated the primary colonization and early succession of bacteria on dead coral surfaces following mortality. This included an examination of the associated changes in production, carbon and nitrogen dynamics of the developing biofilms, and the consequent contributions to reef carbon and nutrient budgets. Inferences were made to the ecosystem changes that may be associated with a decrease in living coral and concomitant increase in bacterial mediated carbon and nutrient processes. Coral mortality via thermal stress resulted in the development of markedly different bacterial communities to those of live corals. Analysis of bacterial primary recruitment and early succession using Fluorescence in situ hybridisation (FISH) allowed direct visualization of bacteria and their spatial heterogeneity within and across samples. Members of the Cytophaga-Flavobacterium-Bacteriodes (CFB) and the gamma Proteobacteria dominated samples from dead corals, while members of the alpha Proteobacteria were apparent over time after coral mortality. Profiling of bacterial populations using Denaturing Gradient Gel Electrophoresis (DGGE) and Terminal- Restriction Fragment Length Polymorphism (T-RFLP) showed significant differences in surface bacterial populations between live and dead coral and that the bacteria on dead corals were dynamic over time post-mortem. In addition, T-RFLP allowed the identification of bacterial species that have previously been linked to nitrogen processes. The results of molecular analysis suggest that significant changes in surface biogeochemistry may occur concurrently with the changes in coral-surface bacteria following coral mortality. Surface associated oxygen metabolism was investigated using a combination of oxygen microelectrode profiles and Pulse Amplitude Modulated (PAM) Fluorometry. Results demonstrated a significant increase in oxygenic photosynthesis from dead coral biofilms. The associated P/R ratios implied a net increase in autotrophic carbon fixation, which was also demonstrated by increases in photosynthetic pigments and algal biomass. The developing biofilms also had greater photosynthetic efficiency, particularly at lower light levels, suggesting a greater capacity for carbon fixation. Changes in nitrogen processes were investigated by nitrogen fixation assays as well as fluxes of NH3/NH4[superscript]+ and NO[subscript]x. A significant increase in nitrogen fixation was observed from dead coral surfaces. These nitrogen fixation rates represented a significant input of ‘new’ nitrogen to coral reefs, particularly in the initial two weeks after coral mortality. Analyses of nitrification and denitrification processes indicated these processes were absent in the initial development period of the dead coral algal-bacterial community. Assessment of the coral surface algal-bacterial biofilm showed an increase in carbon and nitrogen within the biofilms, which suggested that biochemical activity within the biofilm was primarily responsible for the increase in algal biomass observed. Overall, the results demonstrate a change in coral surface biogeochemical processes, which in the context of coral bleaching, may have ecosystem wide consequences. Coral bleaching has already been responsible for the death of large areas of coral. Death of coral over large spatial scales and the consequent increase in bacterial-mediated nutrient cycling may provide a significant input of new nitrogen to the system. This thesis explores the potential significance of these changes for the long term alteration of coral reefs subject to thermal bleaching.

Red spruce trees (Picea rubens Sarg.) occasionally produce short twigs bearing short needles. The frequency of short needle cohorts is positively correlated with both elevation and defoliation and they are found in greater numbers on trees that regularly experience winter injury. Short needles are smaller, have lower fresh and dry weights, and reduced volumes compared with normal needles. They have reduced cross‐sectional areas due to smaller areas of stelar and mesophyll tissue systems. Individual mesophyll cells, however, have the same cross‐ and longitudinal sectional areas. On a weight or volume basis, both short and normal needles contain similar amounts of chlorophyll and carotenoid pigments. When pigment concentration was calculated on a unit needle or a needle area base, short needles contain more pigment than normal needles. Short needles appear to have a greater photosynthetic efficiency as determined by fluorescence measurements.

Abstract Temperatures considered optimum for root growth only occur near the soil surface in interior Alaska, and current literature inadequately describes low soil temperature (i.e. 5 °C) effects on plant development. This study determined shoot and root characteristics of barley (Hordeum vulgare L.) when grown at varying root zone temperatures (RZT). Leaf area, number of leaves and stems, and aerial and root biomass were assessed at heading of barley grown in pots in a glasshouse at RZT of 5, 10, and 15 °C. Plant stage and height were recorded twice weekly. Pots were sectioned at 5 and 10 cm below the soil surface to obtain root lengths and dry weights. Three replications of the experiment used sand as the soil media, a fourth replication used a soil/peat mixture. Plant water use was determined by subtracting the amount of water leached through pots from that added. Plants grown at 5 °C RZT had a 30% slower leaf appearance rate, 50% fewer stems and leaves, and 70% less leaf area than grown at 15 °C. Root length density increased with increasing RZT. Water use and water‐use efficiency were least at 5 °C RZT. Greater specific leaf weights at 5 °C RZT indicated greater photosynthetic efficiency, but reduced water uptake resulted in less dry matter production than at 15 °C RZT.

Two hybrids of maize (Zea mays L.) were compared for low temperature tolerance using a range of characters. The hybrid A665 × H99 (CBD) originated in the Corn Belt of the U.S.A. NZlA × 5-113 (CT) was produced in New Zealand; it is of highland tropical origins and in previous work grew faster than Corn Belt Dent (CBD) hybrids at low temperatures. The objective of this work was to determine if the two hybrids grew at different rates in two contrasting temperature environments approximating those which can occur after planting in New Zealand. Growth analysis, chlorophyll concentration and chlorophyll fluorescence were used to estimate the differences between these hybrids. The plants were grown continuously in a 22/18°C day/night temperature environment or transferred to a 16/14°C environment at the 2-mature-leaf stage. Plants were harvested immediately prior to transfer at the 2-mature-leaf stage and at the 5-mature-leaf stage of development. Differences in dry weight and leaf area were compared with net assimilation rate, chlorophyll concentration and chlorophyll fluorescence as estimates of photosynthetic capacity. Shoot dry weight of CBD was greater than that of CT at 22/18°C, but the reverse was true at 16/14°C, showing that CT hybrids were more tolerant of the transfer to cool temperatures than CBD hybrids. In both environments the leaf areas of CBD and CT were similar. Net assimilation rate and chlorophyll concentration was greater for CT at 16/14°C, suggesting a greater photosynthetic efficiency at lower temperatures. This argument was supported by a slower decline in chlorophyll fluorescence for CT grown at 16/14°C. The coolest temperature treatment used in this work was less effective in discriminating between hybrids for differences in growth in cool environments, compared with the longer periods at 16/6°C of previous work.

SUMMARYSugar‐beet plants were defoliated during growth in seven experiments from 1968 to 1974 either (1) by removing each leaf as it became fully expanded or (2) by removing with scissors as soon as possible all leaves except certain groups up to leaf50, but mainly 6 to20, or (3) by treating the growing point chemically or mechanically in an attempt to stop the production of leaves after the twentieth.Removing mature leaves decreased yields considerably, but removing all leaves except 6–20 did not decrease significantly total dry matter yield of the whole plant and in one experiment increased it by 7% and root weight by 15%. Remaining leaves had a greater photosynthetic efficiency as measured by growth analysis and a 14C02 feeding technique because they were less shaded or there was reduced competition for some nutrient or essential growth component.Additional leaves formed beyond the twentieth resulted in a proportionately lower photosynthetic efficiency of all leaves, but attempts to treat the plant to stop production of new leaves beyond the twentieth were inconclusive.

Potassium naphthenate, 20 mm, was applied to the foliage of 14-day-old plants of bush bean, Phaseolus vulgaris L, cv Top Crop, maize, Zea mays L, cv Golden Bantam, spring wheat, Triticum vulgare Vill., cv Neepawa, and a 2 mm solution to 21-day-old plants of sugar beet, Beta vulgaris L, cv CS-43. Seven days after application, the activities of ribulose diphosphate carboxylase and phosphoenolpyruvic carboxylase in leaves of naphthenate-treated bean and maize were greater than in the leaves of untreated plants. The increase in activity of the carboxylases in treated spring wheat lacked statistical significance. At the same time after treatment, the CO(2) compensation point of bean was smaller than that of control plants, as was the average CO(2) compensation point of sugar beet measured at intervals up to 21 days after spraying. Respiratory rates of embryos of bean seeds soaked for 12, 24, and 48 hours in 43.5 mum K naphthenate were greater than those of seeds soaked in water. Ascorbate oxidase activity in bean leaves, determined 7, 14, and 21 days after K naphthenate application, was also stimulated. Foliar application of 10 mm cyclohexanecarboxylic acid to bean was followed in 7 and 14 days by a greater activity of catalase than in control plants. Higher activity of the enzyme, measured 6, 7, 12, and 14 days after spraying, also resulted from K naphthenate application. The results indicate that the higher rates of photosynthesis in naphthenate-treated plants may be due in part to increased rates of CO(2) fixation, and that greater photosynthetic efficiency, together with a more plentiful supply of ATP arising from increased electron flow in respiration, is involved in the greater growth of plants to which naphthenate has been applied.

Abstract Marketable yield increase of 100% resulted from trellising fresh market cucumbers (Cucumis sativus L.) over a 3-year period. Fruit were a more uniform, dark green color and graded more Fancy and fewer Culls. Fungicidal control of scab (causal agents Cladosporium cucumerinum Ell. & Arth.) was improved by trellising and losses to soil rot (causal agentsRhizoctonia solani Kuhn and Pythium spp.) were eliminated. Suggested reasons for improved yield and quality from trellising include less damage to vines, greater photosynthetic efficiency, improved pest control, and more efficient harvesting.

Seedlings of crested wheatgrass, Agropyron desertorum (Fisch.) Schult., cultivar Summit, and Russian wild ryegrass, Elymus junceus Fisch., cultivar Sawki, were grown in the greenhouse for 7 weeks. Each week 20 plants were destructively harvested for growth analysis. Leaf and tiller numbers and leaf lengths were recorded for an additional 10 plants of each species. Mean net assimilation rate of crested wheatgrass was significantly higher (P < 0.01) than that of Russian wild ryegrass, apparently indicating greater photosynthetic efficiency in the former. In 7 weeks, crested wheatgrass seedlings produced nearly twice as much total dry matter as Russian wild ryegrass seedlings.