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The impact of Stevia rebaudiana leaf on feeding preferences of an insect, a mite, and a mammal was investigated. The grasshopper, Valanga irregularis of the Acrididae family, avoided feeding on S. rebaudiana leaf, as evidenced by a decrease in animal weight. Increased mortality on S. rebaudiana feed was ascribed to feeding avoidance to the point of starvation. The extent of red spider mite ( Tetranychus urticae) damage was not proportional to leaf steviol glycoside (SG) concentration, a result ascribed to a feeding mechanism that avoids chlorenchyma cells that contain SGs. Guinea pigs ( Cavia porcellus) were presented with the choice between a control feed and feed amended to contain 5% sucrose or 0.02%, 4%, or 10% (dry weight) of S. rebaudiana leaf. Feed intake increased (39% above the control) for the diet involving high levels of SG amendment of feed (10% S. rebaudiana leaf). Encouragement of general mammalian herbivory may provide ecological fitness to S. rebaudiana if it is more tolerant of grazing pressure than other plants in its environment. Improvement in feed intake may have commercial implication for use of S. rebaudiana as an additive in stock feeds.

Steviol glycosides (SG) (with stevioside and rebaudioside A predominating) are present in wild-type Stevia rebaudiana, at approximately 10% of dry weight (dw), prompting a consideration of the autoecological role played by these compounds in terms of energy (C) storage and/or osmoregulation. The leaf starch pool was observed to change diurnally with respect to the light cycle (from 3.29% to 0.73% of leaf dw between dusk and dawn) and also to increase under constant light treatment (from 1.53% to 6.25% of leaf dw), while SG pools were relatively constant (around 6% w/dw). A similar trend was observed during exposure to elevated CO 2 (800 ppm), with starch increasing (from 10% to 15% of leaf dw), while SG pool size was constant (around 12% w/dw). For plants subject to increasing water stress over several days, an increase in leaf sap osmolality was observed in the leaves of a severely stressed group (from -1 MPa to -3 MPa, after 2 days of treatment), while stevioside and rebaudioside A leaf concentration was relatively constant (around 16% w/dw). These results are not consistent with a role for SG as either a short-term C store or osmoregulator in S. rebaudiana.

This study provides a comprehensive investigation on the impact of increasing NaCl concentrations on hydroponically grown Stevia rebaudiana cultivars (Shoutian-2 and Fengtian). Growth parameters including plant height, biomass and physiological responses including osmotic potential were measured. In addition, the levels of steviol glycosides, elements and primary metabolites were measured and statistically evaluated. The cultivar Fengtian grew faster, accumulated less Na + and compatible organic solutes, and more K + in the leaves, as compared to the cv. Shoutian-2. Metabolite analysis identified 81 differentially accumulated metabolites, indicating an alteration in the metabolite phenotype of both cultivars upon exposure to salinity A general increase in many amino acids, amines, sugars and sugar phosphates with a concurrent decrease in most organic acids; including tricarboxylic acid (TCA) cycle intermediates, was observed. In the more salt tolerant cv. Fengtian, the levels of hexose phosphates and metabolites involved in cellular protection increased in response to salinity. These metabolites remained unchanged in the sensitive cv. Shoutian-2. Interestingly, salt treatment notably increased the rebaudioside A concentration by 53% while at the same time stevioside decreased by 38% in Fengtian which has important implications for controlling the relative amounts of reboudioside A and stevioside. The findings of this study leads to the conclusion that mild salinity stress can increase the yield of sweetener compounds, which is dependent on the cultivar and the level of salinity stress., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Feeding treatments were imposed in two feeding trials involving Cobb broiler and Bond Brown layer birds. Three feed additives (biochar, bentonite and zeolite) were supplied at four rates (0, 1, 2 and 4% w/w) in feed, as previously considered in the context of animal production, was considered in the context of Excreta chemical and water retention properties and granulation characteristics of decomposed excreta (manure) were characterised. At field capacity (- 0.01 MPa), manure produced from control and 4% bentonite diets contained significantly (p = 0.001) more water (at 1.93 and 2.44% v/v water, respectively) than zeolite and biochar treatments. Manure mesoporosity was significantly (p = 0.015) higher in 2 and 4% bentonite treatments than other feed additives. Fresh excreta from layer birds on the control diet contained 6% w/dw N and 35% C, which was decreased to 2.6% N and 28% C after decomposition, with C:N ratio changing from 5.9 to 12.1. Ammonia loss was higher from biochar and zeolite manures than control or bentonite, associated with higher pH in the biochar and zeolite manures. More N was unaccounted from bentonite manure than other treatments, presumably lost as N 2 O or N 2 , a result linked to its higher moisture content and its enhanced rate of denitrification. The highest proportion of granules in the size class desired for fertilizer spreading was achieved using decomposed manure from the 1 and 2% w/w biochar treatments of the broiler trial, and 1 and 2% zeolite and 4% biochar treatments of the layer trial. Thus the feed amendments improved poultry manure in specific ways., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

According to the World Health Organisation, antibiotics are rapidly losing potency in every country of the world. Poultry are currently perceived as a major source of pathogens and antimicrobial resistance. There is an urgent need for new and natural ways to control pathogens in poultry and humans alike. Porous, cation rich, aluminosilicate minerals, zeolites can be used as a feed additive in poultry rations, demonstrating multiple productivity benefits. Next generation sequencing of the 16S rRNA marker gene was used to phylogenetically characterize the fecal microbiota and thus investigate the ability and dose dependency of zeolite in terms of anti-pathogenic effects. A natural zeolite was used as a feed additive in laying hens at 1, 2, and 4% w/w for a 23 week period. At the end of this period cloacal swabs were collected to sample faecal microbial communities. A significant reduction in carriage of bacteria within the phylum Proteobacteria, especially in members of the pathogen-rich family Enterobacteriaceae, was noted across all three concentrations of zeolite. Zeolite supplementation of feed resulted in a reduction in the carriage of a number of poultry pathogens without disturbing beneficial bacteria. This effect was, in some phylotypes, correlated with the zeolite concentration. This result is relevant to zeolite feeding in other animal production systems, and for human pathogenesis., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

A range of feed supplements, including antibiotics, have been commonly used in poultry production to improve health and productivity. Alternative methods are needed to suppress pathogen loads and maintain productivity. As an alternative to antibiotics use, we investigated the ability of biochar, bentonite and zeolite as separate 4% feed additives, to selectively remove pathogens without reducing microbial richness and diversity in the gut. Neither biochar, bentonite nor zeolite made any significant alterations to the overall richness and diversity of intestinal bacterial community. However, reduction of some bacterial species, including some potential pathogens was detected. The microbiota of bentonite fed animals were lacking all members of the order Campylobacterales. Specifically, the following operational taxonomic units (OTUs) were absent: an OTU 100% identical to Campylobacter jejuni; an OTU 99% identical to Helicobacter pullorum; multiple Gallibacterium anatis (>97%) related OTUs; Bacteroides dorei (99%) and Clostridium aldenense (95%) related OTUs. Biochar and zeolite treatments had similar but milder effects compared to bentonite. Zeolite amended feed was also associated with significant reduction in the phylum Proteobacteria. All three additives showed potential for the control of major poultry zoonotic pathogens.

Silverleaf whitefly (SLW, Bemisia tabaci MEAM1) and aphids are sap-sucking insects, which pose a serious threat to Australian cucurbit crops and the horticulture industry. Traditional chemical control for these insect pests is becoming less effective, and there is a need to search for alternative or supplementary methods. This study aimed to manipulate the habitat of pumpkin crops in a tropical setting (Queensland, Australia), by growing pumpkins (var. Japanese pumpkin) alone and between lablab (Lablab purpureus L. Sweet). It was hypothesized that the presence of lablab will increase the populations of natural enemies, and through their control of insect pests such as SLW and aphids, will affect pumpkin yield. The population of arthropods (natural enemies and pests of pumpkin), with a focus on SLW and aphids, were sampled weekly on both lablab and pumpkin crop for a total of 21 weeks. Results showed that lablab hosted more enemies of SLW per plant than pumpkin in either treatment. In addition, adult SLW numbers were significantly higher in the pumpkin-only crop compared with the pumpkin grown between lablab, while pumpkin in the mixed plantings had significantly more ladybirds and lacewing larvae (P < 0.05). While there was no significant difference in the average fruit weight between treatments, the total weight (kg) and number of marketable pumpkins per hectare was greater (P < 0.05) for the pumpkin/lablab treatment than the pumpkin-only treatment. This study shows that growing lablab alongside a pumpkin crop may enhance natural enemies of SLW and could significantly increase the yield.

A comparative study was performed on compost extracts prepared from cattle rumen content composted for three and nine months, nine month old compost inoculated with a Nutri-Life 4/20™ inoculum, and two commercial preparations (LivingSoil™ and Nutri-Life 4/20™), all incubated for 48h. Nutri-Life 4/20™ had the highest concentrations of NO(3)(-)-N and K(+)-K, while rumen compost extract had higher humic and fulvic acids concentration. The bacterial and fungal community level functional diversity of three month old compost extract and of LivingSoil™, assessed with Biolog™, were higher than that of nine month old rumen compost extract, with or without Nutri-Life 4/20™ inoculum, or Nutri-Life 4/20™. No difference in fungal diversity was observed between treatments, as indicated by Denaturing Gradient Gel Electrophoresis (DGGE) analysis, however, bacterial diversity was higher in all compost extracts and LivingSoil™ compared to the Nutri-Life 4/20™. Criteria for judging the quality of a microbially enhanced extract are discussed., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Microbially enhanced compost extracts ('compost tea') are being used in commercial agriculture as a source of nutrients and for their perceived benefit to soil microbiology, including plant disease suppression. Rumen content material is a waste of cattle abattoirs, which can be value-added by conversion to compost and 'compost tea'. A system for compost extraction and microbial enhancement was characterised. Molasses amendment increased bacterial count 10-fold, while amendment based on molasses and 'fish and kelp hydrolysate' increased fungal count 10-fold. Compost extract incubated at 1:10 (w/v) dilution showed the highest microbial load, activity and humic/fulvic acid content compared to other dilutions. Aeration increased the extraction efficiency of soluble metabolites, and microbial growth rate, as did extraction of compost without the use of a constraining bag. A protocol of 1:10 dilution and aerated incubation with kelp and molasses amendments is recommended to optimise microbial load and fungal-to-bacterial ratio for this inoculum source., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Physico-chemical and microbiological investigations were carried out on rumen content material composted for nine months, fresh vermicasts (obtained after passing the same compost through the guts of a mixture of three species of earthworms: Eisenia fetida, Lumbricus rubellus and Perionyx excavates) and microbially enhanced extracts derived from rumen compost, vermicast and vermicast leachate incubated for up to 48 h. Compared to composted rumen contents, vermicast was only improved in terms of microbial biomass C, while vermicast leached extract was significantly higher in NH(4)(+)-N,PO(4)(-)-P, humic acid, bacterial counts and total microbial activity compared to rumen compost extract. Although no difference between treatments was observed in genetic diversity as indicated by DGGE analysis, community level functional diversity of vermicast leached extract (Biolog™) was higher than that of composted rumen contents, vermicast and rumen compost extract indicating an enhancement of microbial activity rather than diversity due to liquid incubation., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Cucurbit crops host a range of serious sap-sucking insect pests, including silverleaf whitefly (SLW) and aphids, which potentially represent considerable risk to the Australian horticulture industry. These pests are extremely polyphagous with a wide host range. Chemical control is made difficult due to resistance and pollution, and other side-effects are associated with insecticide use. Consequently, there is much interest in maximising the role of biological control in the management of these sap-sucking insect pests. This study aimed to evaluate companion cropping alongside cucurbit crops in a tropical setting as a means to increase the populations of beneficial insects and spiders so as to control the major sap-sucking insect pests. The population of beneficial and harmful insects, with a focus on SLW and aphids, and other invertebrates were sampled weekly on four different crops which could be used for habitat manipulation: Goodbug Mix (GBM; a proprietary seed mixture including self-sowing annual and perennial herbaceous flower species); lablab (Lablab purpureus L. Sweet); lucerne (Medicago sativa L.); and niger (Guizotia abyssinica (L.f.) Cass.). Lablab hosted the highest numbers of beneficial insects (larvae and adults of lacewing (Mallada signata (Schneider)), ladybird beetles (Coccinella transversalis Fabricius) and spiders) while GBM hosted the highest numbers of European bees (Apis mellifera Linnaeus) and spiders. Lucerne and niger showed little promise in hosting beneficial insects, but lucerne hosted significantly more spiders (double the numbers) than niger. Lucerne hosted sig-nificantly more of the harmful insect species of aphids (Aphis gossypii (Glover)) and Myzus persicae (Sulzer)) and heliothis (Heliothis armigera Hübner). Niger hosted significantly more vegetable weevils (Listroderes difficillis (Germar)) than the other three species. Therefore, lablab and GBM appear to be viable options to grow within cucurbits or as field boundary crops to attract and increase beneficial insects and spiders for the control of sap-sucking insect pests. Use of these bio-control strategies affords the opportunity to minimise pesticide usage and the risks associated with pollution.

Impacts of salinity become severe when the soil is deficient in oxygen. Oxygation (using aerated water for subsurface drip irrigation of crop) could minimize the impact of salinity on plants under oxygen-limiting soil environments. Pot experiments were conducted to evaluate the effects of oxygation (12% air volume/volume of water) on vegetable soybean (moderately salt tolerant) and cotton (salt tolerant) in a salinized vertisol at 2, 8, 14, 20 dS/m EC(e). In vegetable soybean, oxygation increased above ground biomass yield and water use efficiency (WUE) by 13% and 22%, respectively, compared with the control. Higher yield with oxygation was accompanied by greater plant height and stem diameter and reduced specific leaf area and leaf Na+ and Cl- concentrations. In cotton, oxygation increased lint yield and WUE by 18% and 16%, respectively, compared with the control, and was accompanied by greater canopy light interception, plant height and stem diameter. Oxygation also led to a greater rate of photosynthesis, higher relative water content in the leaf, reduced crop water stress index and lower leaf water potential. It did not, however, affect leaf Na+ or Cl- concentration. Oxygation invariably increased, whereas salinity reduced the K+ : Na+ ratio in the leaves of both species. Oxygation improved yield and WUE performance of salt tolerant and moderately tolerant crops under saline soil environments, and this may have a significant impact for irrigated agriculture where saline soils pose constraints to crop production.

Within-plant light and nutrient environments are spatially and temporally heterogeneous. The development of different parts of a plant is highly coordinated, which enables the efficient capture and use of resources in such heterogeneous environments. The physiological mechanisms underlying the correlative control of distantly located plant tissues and organs are still not fully understood. In this study, a mathematical model based on a self-organisation mechanism for resource allocation mediated by polar auxin transport is proposed to explain the origin of correlative effects among shoot branches. In the model, the shoot system of an individual plant is treated as a collection of relatively independent modular subunits competing for root-derived resources. The allocation of root-derived resources to different parts of the shoot is determined by their relative vascular contacts with the root system. The development of the vascular network is specified by the polar transport of auxin produced by various parts of the shoot in response to their immediate internal and external environments. The simulation results show that, by altering the amount of auxin they release individually in response to the local environment and modifying their relative vascular contact with the root system, subunits of a shoot are able to coordinate without a central controller and self-organise into functional and structural patterns such as light foraging and correlative dominance. This modelling study suggests that morphological dynamics at the whole-plant level can be understood as the sum of all modular responses to their local environments. The concept of self-organisation holds great promise for an in-depth understanding of the organisational laws that generate overall plant structure and functions.

The hypothesis that hyperaccumulation of certain metals in plants may play a role in osmotic adjustment under water stress (drought) was tested in the context of nickel hyperaccumulator Stackhousia tryonii. Field-collected mature plants of S. tryonii, grown in native ultramafic soil, were pruned to soil level and the re-growth exposed to five levels of water stress (20, 40, 60, 80 and 100% field capacity; FC) for 20 weeks. Water stress had significant (P<0.05) influence on growth (biomass), water potential and shoot Ni concentrations, with progressively more impact as water stress was increased from 80 to 40% FC. Shoot Ni concentration increased significantly from 3,400 microg g(-1) dry weight (at 100% FC) to 9,400 microg g(-1) dry weight (at 20% FC). Assuming that Ni is uniformly distributed through the shoot tissue, the Ni concentration could account for 100% at the 80 and 60% FC conditions, and 50% at the 40 and 20% FC conditions of plant osmotic regulation. The results are consistent with a role of Ni in osmotic adjustment and protection of S. tryonii plants against drought.

Background and Aims: Nitrate is the major nitrogen source for many plants. The first step of the nitrate assimilation pathway is the reduction of nitrate to nitrite, catalysed by nitrate reductase (NR). Circadian oscillations in expression and activity of NR have been demonstrated in many plant species. The pathway by which this circadian behaviour is regulated remains to be elucidated. In this study, based on recent experimental observations, a mathematical model is proposed to explain the origin of diurnal and circadian oscillations in NR gene expression and enzyme activity., Methods: The dynamic model is based on the feedback interconnections between NR and its substrate, nitrate. In the model, NR activity is regulated at the transcriptional level, in response to the balance between nitrate influx and reduction, and at the post-translational levels in response to signals from carbon assimilation. Conditions for the model system to generate self-sustained circadian oscillations are investigated by numerical simulations., Key Results and Conclusions: Under light/dark cycles, the simulation results are in agreement with the observed diurnal pattern of changes in leaf nitrate concentration, NR transcript level and NR activity. Within a range of kinetic parameter values, circadian oscillation behaviour persists even under constant light, with periods of approx. 24 h. These simulation results suggest that sustained circadian oscillations can originate from the feedback interactions between NR and its substrate, nitrate, without the need to postulate the existence of an endogenous 'circadian clock'.

Background and Aims: Stackhousia tryonii, a rare nickel hyperaccumulating herb, is endemic to ultramafic (serpentine) soils of central Queensland, Australia. The effects of eight dormancy-relieving treatments on germination of stored seeds of Stackhousia tryonii were investigated under controlled light and temperature conditions. *, Methods: The treatments were: untreated (control i), leached and dehydrated (primed control ii), treating with gibberellic acid (150 and 300 microM), smoke extract (5 and 10 %, v/v) and potassium cyanide (40 and 80 mM). *, Key Results: Freshly harvested seeds did not germinate. Germination percentage increased with time of storage for up to 18 months (38.3 %). Gibberellin, smoke extract and cyanide treatments did not significantly improve germination. Light did not affect seed germination and there was no interaction between dormancy-relieving treatments and light. A significant inhibition of germination occurred in seeds treated with 5 % (but not 10 %) aqueous smoke extract. Saturated fatty acids, predominantly tridecanoic (C13:0), constituted about 90 % of the total fatty acids in the oil of freshly harvested seeds. In contrast, there was increased accumulation (>75 %) of mono-unsaturated (oleic, c18:1) and poly-unsaturated (linoleic, c18:2; linolenic, c18:3) fatty acids in the oil of stored seeds. *, Conclusions: Seeds of S. tryonii require an after-ripening period for germination.

The Central Queensland University (CQU) has championed a self-contained concrete lined evapotranspiration channel. Any non-transpired effluent returns to a holding tank and is recirculated through the evapotranspiration channel until it is used. This paper examines the results from the Rockhampton trial site. Nutrient ions in the effluent were quantified over time and found not to accumulate in solution. Microbial analysis of the treated effluent was performed and was found to be within the ranges required by the relevant legislative codes. Citrus fruit grown in the evapotranspiration channel were sampled and no elevated levels of faecal coliforms were recorded. Macronutrients and micronutrients of the soil in the channels were measured over a 5-year period. No toxic accumulations or nutrient deficiencies in the soil occurred. Levels of salinity and sodicity in the evapotranspiration channel soil were quantified. Salinity rose slightly, as did sodium. Concentrations of salts and sodium did not reach unsustainable levels. The aim of the trial was to develop an on-site treatment and reuse system that is sustainable and protects public and environmental health.

Main Conclusion: The combination of water and gas at an aeration rate of 15 mg/L and irrigation amount of 0.8 Ep significantly promoted the root morphology, inter-root soil bacterial community structure and diversity of pepper, enhanced the structure of molecular symbiotic network, and stimulated the potential ecosystem function. Poor aeration adversely affects the root morphology of pepper (Capsicum annuum L.) and bacterial community. It is critical to understand the effects of water-air interactions on root morphology and bacterial community structure and diversity. A randomized block experiment was conducted under the two aeration rates of dissolved oxygen mass concentrations, including A: 15 mg/L, O: 40 mg/L, and C: non-aeration as control treatment, and two irrigation rates of W 1 and W 2 (0.8 Ep and 1.0 Ep). The results showed that aerated irrigation had a significant effect on the root morphology of pepper. Compared with treatment CW 1 , treatment AW 1 increased root dry weight, root length, root volume, and root surface area by 13.63%, 11.09%, 59.47%, and 61.67%, respectively (P < 0.05). Aerated irrigation significantly increased the relative abundance of Actinobacteria, Gemmatimonadetes, Alphaproteobacteria, Gemmatimonas, Sphingomonas, and KD4-96 aerobic beneficial bacteria. It decreased the relative abundance of Proteobacteria, Monomycetes, Bacteroidetes, Corynebacterium, Gammaproteobacteria, Anaerolineae, Subgroup&#95;6, MND1, Haliangium, and Thiobacillus. The Pielou&#95;e, Shannon and Simpson indexes of treatment AW 1 were significantly higher than treatments OW 1 and CW 1 . The results of the β-diversity of bacterial communities showed that the structure of soil bacterial communities differed significantly among treatments. Actinobacteria was a key phylum affecting root morphology, and AW 1 treatment was highly correlated with Actinobacteria. Molecular ecological network analysis showed a relatively high number of bacterial network nodes and more complex relationships among species under the aeration of level 15 mg/L and 0.8 Ep, as well as the emergence of new phylum-level beneficial species: Dependentiae, BRC1, Cyanobacteria, Deinococcus-Thermus, Firmicutes, and Planctomycetes. Therefore, the aeration of 15 mg/L and 0.8 times crop-evaporation coefficient can increase root morphology, inter-root soil bacterial community diversity and bacterial network structure, and enhance potential ecosystem functions in the rhizosphere., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The micro and nano bubble (MNB) technology, due to its promising features and advantages, has become increasingly popular in agriculture. MNB-treated water positively impacts plant growth, especially when it is treated with a combination of gas-like carbon dioxide (CO 2 ), injected through the MNB generator. Therefore, this study used MNB water with CO 2 that are small bubbles of nanometer and micrometer diameters having several unique physical properties that make them useful for water treatments. This research evaluates the effect of MNBs and CO 2 -treated water on leafy vegetable Amaranth green (Amaranthus viridis). The experiment divided the Amaranth plants into three major groups, G1, G2, and G3, irrigated by MNB water with dissolved CO 2 , MNBs with only Air, and simple tap water, respectively. The first treatment group (G1) (MNBs with CO 2 ) was further divided into three sub-divisions, i.e., G1A, G1B, G1C, and the second treatment group G2 (MNBs with Air) was divided into three sub-groups, i.e., G2A, G2B, and G2C, while the third group G3 with only one category as only controlled group. These sub-divisions of treatment groups G1 and G2 were done to investigate the impact of MNBs and CO 2  treated water with different time durations. For example, in G1A, the water treatment with MNBs and CO 2 was kept five minutes, for G1B 10 minutes, and G1C 15 minutes. Similar method was adopted for G2 as well. According to the results, water treated with MNB and CO 2 has a significant (90%) impact on the Amaranth germination rate and plant growth. Specifically, pots irrigated with the MNBs + CO 2 -treated water showed better germination and plant growth rate than the MNBs + Air treated water. Overall, both treatment groups, G1 and G2, showed significantly higher impacts than the CK groups (simple water). Further, this experiment showed that the 10 and 15 minutes treatment of water (G1B, G1C and G2B, G2C) increased the stem height and root size compared to the 5 minutes treated water (G1A, G2A). This study concludes that the water with MNBs has a positive impact on the vegetables and can be an effective technology to improve crop yield., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Key Message: Candidate male sterility genes were identified in sugarcane, which interacts with kinase-related proteins, transcription factors, and plant hormone signaling pathways to regulate stamen and anther development. Saccharum officinarum is a cultivated sugarcane species that its predominant feature is high sucrose content in stems. Flowering is necessary for breeding new cultivars but will terminate plant growth and reduce sugar yield. The wild sugarcane species Saccharum spontaneum has robust and viable pollen, whereas most S. officinarum accessions are male sterile, which is a desirable trait of a maternal parent in sugarcane breeding. To study male sterility and related regulatory pathways in sugarcane, we carried out RNAseq using flowers in different developmental stages between male-sterile S. officinarum accession 'LA Purple' and fertile S. spontaneum accession 'SES208'. Gene expression profiles were used to detect how genes are differentially expressed between male sterile and fertile flowers and to identify candidate genes for male sterility. Weighted gene correlation networks analysis (WGCNA) was conducted to investigate the regulatory networks. Transcriptomic analyses showed that 988 genes and 2888 alleles were differentially expressed in S. officinarum compared to S. spontaneum. Ten differentially expressed genes and thirty alleles were identified as candidate genes and alleles for male sterility in sugarcane. The gene Sspon.03G0007630 and two alleles of the gene Sspon.08G0002270, Sspon.08G0002270-2B and Sspon.08G0014700-1A, were involved in the early stamen or carpel development stages, while the remaining genes were classified into the post-meiosis stage. Gibberellin, auxin, and jasmonic acid signaling pathways are involved in the stamen development in sugarcane. The results expanded our knowledge of male sterility-related genes in sugarcane and generated genomic resources to facilitate the selection of ideal maternal parents to improve breeding efficiency., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In the present scenario, waste management, especially agro-waste, is one of the major challenges. India is an agrarian country and the economy depends on agriculture and a huge amount of agro-wastes are generated. In this study, biochar was prepared from paddy straw and sugarcane bagasse and was used in the feed of genetically improved farm tilapia (GIFT) at 0.5% (w/w) basis to study its effect on growth and haematological parameters. An experiment was carried out in triplicate in 500-l capacity FRP tanks comprising two treatments and one control. Tanks were filled with inland saline soil to maintain 25-cm soil's bed and water with 12 ppt salinity. A total of 22 fish having an average length of 5.14 ± 0.07 cm and weight of 4.8 ± 0.05 g were stocked in each tank; the fish were fed at apparent satiation level, twice daily for 45 days. It was observed that growth parameters like SGR% (specific growth rate), weight gain (WG%), and feed conversion ratio (FCR) were significantly improved (p < 0.05) than the control. Biochar-enriched feed also significantly improved the haematological parameters like red blood cell (RBC), white blood cell (WBC), haemoglobin (Hb) haematocrit % (HCT), mean cell haemoglobin concentration (MCH), and MCV (mean cell volume) in treatment groups than the control. Feeding biochar as feed additives was also found to decrease catalase (CAT) and enhanced amylase and lipase activities in treatments as compared to control (p < 0.05). It can be concluded that the application of biochar as a feed additive enhanced the growth and overall health of the fish, and it can enhance fish production. However, biochar from sugarcane bagasse was found to be more effective than the paddy straw biochar in the diet of tilapia (GIFT)., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: All authors agree to publish in ESPR journal. Conflict of interest: The authors declare no competing interests. , (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Key Message: Transcriptome analysis revealed the potential mechanism of nitrogen regulating steviol glycosides synthesis via shifting of leaf carbon metabolic flux or inducing certain transcription factors. Nitrogen (N) plays key regulatory roles in both stevia (Stevia rebaudiana) growth and the synthesis of its functional metabolite steviol glycosides (SGs), but the mechanism by which this nutrient regulates SGs synthesis remains to be elucidated. To address this question, a pot experiment was performed in a greenhouse where stevia plants fertilized with N (the control as CK plants) and compared with plants without the supply of N. Physiological and biochemical analyses were conducted to test the growth and metabolic responses of plants to N regimes. Our results showed that N deficiency significantly inhibited plant growth and leaf photosynthesis, while increased leaf SGs contents in stevia (49.97, 46.64 and 84.80% respectively for rebaudioside A, stevioside, and rebaudioside C), which may be partly due to "concentration effect". Then, transcriptome analysis was conducted to understand the underlying mechanisms. A total of 535 differentially expressed genes were identified, and carbon metabolism-related events were highlighted by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Many of these genes were significantly upregulated by N-deficiency, including those involved in "phenylpropanoid biosynthesis", "flavonoid biosynthesis" and "starch and sucrose metabolism". Our study also analyzed the expression patterns of SGs synthesis-related genes under two N regimes and the potential transcription factors linking N nutrition and SG metabolism. N-deficiency may promote SGs synthesis by changing the carbon metabolism flux or inducing certain transcription factors. Our results provide deeper insight into the relationship between N nutrition and SGs synthesis in stevia plants., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Non-nutritive sweeteners (NNS) are commonly used in sweetened foods and beverages; however their role in metabolic regulation is still not clear. In this experiment, we used guinea pigs as an animal model to study the effect of NNS on body growth and intestinal health by modifying gut microbiota and hypothalamus-related proteins., Results: For a 28-day feeding experiment a total of 40 guinea pigs were randomly divided into four groups, one control (CN) group and three treatments, in which three NNS were added to the diet: rebaudioside A (RA, 330 mg kg -1 ), sodium saccharin (SS, 800 mg kg -1 ), and sucralose (TGS, 167 mg kg -1 ), respectively. The TGS group exhibited significantly reduced food consumption in comparison with the CN group (P < 0.05) whereas the RA group showed increased food consumption in comparison with the CN group (P < 0.05). Notably, Taste receptor type 1 subunit 2 (T1R2) expression in the hypothalamus was significantly higher in the RA group than in the CN group (P < 0.05). The mRNA expressions of appetite-stimulated genes arouti-related neuropeptide (AGRP), neuropeptide Y (NPY), and thyroid stimulating hormone (TSHB) were significantly higher than those in the CN group (P < 0.05) but mRNA expressions of appetite-suppressed genes tryptophan hydroxylase 2(THP2) were significantly lower in the TGS group (P < 0.05). Furthermore, NNS in the guinea pig diets (RA, SS, TGS) significantly increased the relative abundance of Muribaculaceae but decreased the relative abundance of Clostridia&#95;vadin BB60 in comparison with the CN group (P < 0.05). We also found that dietary supplementation with RA also significantly altered the relative abundance of Lactobacillus., Conclusion: Our finding confirmed that dietary supplementation with RA and TGS affected body growth and intestinal health by modulating hypothalamic RNA profiles and ileum microbiota, suggesting that NNS should be included in guinea-pig feeding. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Increased gas emissions from soil into the atmosphere are one form of ecosystem feedback in response to climate change. Soil temperature plays a critical role in the soil emission of carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) suggesting that the release of gases can be reduced by regulating soil temperature. This study proposes a green microencapsulated phase-change material (mPCM) as a soil temperature regulator due to its ability to absorb and release heat during temperature phase transition. The objective is to test how mPCM in soil mixtures influences CO 2 and N 2 O fluxes under laboratory-controlled conditions. For this purpose, a series of soil incubations were carried out with different temperature regimes and soil moisture. The test results revealed that at 20% soil moisture mPCM reduced cumulative CO 2 emissions from the soil by 16.4% during the thawing stage and by 20.5% during the freezing stage. At 25% soil moisture, mPCM showed a greater effect reducing cumulative CO 2 emissions by 23.9% during the thawing stage and by 24.2% during the freezing stage. At below-zero temperatures, mPCM reduced the total N 2 O flux by 11.6% at 20% soil moisture and by 26.0% at 25% soil moisture, compared to soil without mPCM. As soil moisture increased, the effects of mPCM on CO 2 and N 2 O fluxes became more pronounced. Cyclic freezing and thawing of soil led to an increase in gas flux. This variation was reduced by the mPCM due to its ability to mitigate the change of soil temperature. Inhibition of the rise in soil temperature due to the inclusion of mPCM reduced the rate of activation of soil mineralization, which reduced gas fluxes. This study demonstrates the potential of mPCM application to reduce greenhouse gas emissions from soil through thermoregulation., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Nutrient allocation is central to understanding plant ecological strategies and forest roles in biogeochemical cycles. Thought to be mainly driven by environmental conditions, nutrient allocation to woody organs, especially to living tissues, is poorly understood. To examine the role of differences in living tissues (sapwood, SW, vs inner bark, IB), organs, ecological strategies, and environmental conditions in driving nutrient allocation and scaling in woody plants, we quantified nitrogen and phosphorus in main stems and coarse roots of 45 species from three tropical ecosystems with contrasting precipitation, fire regime, and soil nutrients. Nutrient concentration variation was mostly explained by differences between IB and SW, followed by differences between species and, in the case of phosphorus, soil nutrient availability. IB nutrient concentrations were four times those of SW, with root tissues having slightly higher concentrations than stem tissues. Scaling between IB and SW, and between stems and roots, was generally isometric. In cross-sections, IB contributed half of total nutrients in roots and a third in stems. Our results highlight the important role of IB and SW for nutrient storage, the coordination in nutrient allocation across tissues and organs, and the need to differentiate between IB and SW to understand plant nutrient allocation., (© 2023 The Authors. New Phytologist © 2023 New Phytologist Foundation.)

The primary objective of this work was to investigate how the dominant microbial species change and affect C and N losses under aerobic and aerobic-anaerobic-coupled composting of mown hay (MH, ryegrass) and corn stover (CS) mix. Results showed that C and N losses in aerobic compost of MH-CS were significantly decreased by 19.57-31.47% and 29.04-41.18%, respectively. 16S rRNA gene sequencing indicated that the bacterial microbiota showed significant differences in aerobic and aerobic-anaerobic-coupled composting. LEfSe analyses showed that aerobic composting promoted the growth of bacteria related to lignocellulosic degradation and nitrogen fixation, while aerobic-anaerobic-coupled composting promoted the growth of bacteria related to denitrification. Correlation analysis between bacterial community and environmental factors indicated that moisture content (MC) was the most important environmental factor influencing the differentiation of bacterial growth. KEGG analysis showed that aerobic composting enhanced the amino acid, carbohydrate, and other advantageous metabolic functions compared to that of aerobic-anaerobic-coupled composting. As a conclusion, the addition of 10-20% corn stover (w/w) to new-mown hay (ryegrass) appeared to inhibit anaerobic composting and prompt aerobic composting in MH-CS mix, which led to the effective utilization of mown hay as a resource for composting., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Plants require oxygen to respire and produce energy. Plant cells are exposed to low oxygen levels (hypoxia) in different contexts and have evolved conserved molecular responses to hypoxia. Both environmental and developmental factors can influence intracellular oxygen concentrations. In nature, plants can experience hypoxic conditions when the soil becomes saturated with water following heavy precipitation (i.e., waterlogging). Hypoxia can also arise in specific tissues that have poor gas exchange with atmospheric oxygen. In this case, hypoxic niches that are physiologically and developmentally relevant may form. To dissect the molecular mechanisms underlying the regulation of hypoxia response in plants, a wide range of hypoxia-inducing methods have been used in the laboratory setting. Yet, the different characteristics, pros and cons of each of these hypoxia treatments are seldom compared between methods, and with natural forms of hypoxia. In this chapter, we present both environmental and developmental forms of hypoxia that plants encounter in the wild, as well as the different experimental hypoxia treatments used to mimic them in the laboratory setting, with the aim of informing on what experimental approaches might be most appropriate to the questions addressed, including stress signaling and regulation., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Key Message: Vegetative-to-reproductive phase transition in female cannabis seedlings occurs autonomously with the de novo development of single flowers. To ensure successful sexual reproduction, many plant species originating from seedlings undergo juvenile-to-adult transition. This phase transition precedes and enables the vegetative-to-reproductive shift in plants, upon perception of internal and/or external signals such as temperature, photoperiod, metabolite levels, and phytohormones. This study demonstrates that the juvenile seedlings of cannabis gradually shift to the adult vegetative stage, as confirmed by the formation of lobed leaves, and upregulation of the phase-transition genes. In the tested cultivar, the switch to the reproductive stage occurs with the development of a pair of single flowers in the 7th node. Histological analysis indicated that transition to the reproductive stage is accomplished by the de novo establishment of new flower meristems which are not present in a vegetative stage, or as dormant meristems at nodes 4 and 6. Moreover, there were dramatic changes in the transcriptomic profile of flowering-related genes among nodes 4, 6, and 7. Downregulation of flowering repressors and an intense increase in the transcription of phase transition-related genes occur in parallel with an increase in the transcription of flowering integrators and meristem identity genes. These results support and provide molecular evidence for previous findings that cannabis possesses an autonomous flowering mechanism and the transition to reproductive phase is controlled in this plant mainly by internal signals., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The control of infectious diseases has always been a top medical priority. For years during the so-called antibiotic era, we enjoyed prolonged life expectancy and the benefits of superior pathogen control. The devastating failure of the medical system, agriculture and pharmaceutical companies and the general population to appreciate and safeguard these benefits is now leading us into a grim post-antibiotic era. Antimicrobial resistance (AMR) refers to microorganisms becoming resistant to antibiotics that were designed and expected to kill them. Prior to the COVID-19 pandemic, AMR was recognised by the World Health Organization as the central priority area with growing public awareness of the threat AMR now presents. The Review on Antimicrobial Resistance, a project commissioned by the UK government, predicted that the death toll of AMR could be one person every 3 seconds, amounting to 10 million deaths per year by 2050. This review aims to raise awareness of the evergrowing extensiveness of antimicrobial resistance and identify major sources of this adversity, focusing on agriculture's role in this problem and its solutions. KEYPOINTS: • Widespread development of antibiotic resistance is a major global health risk. • Antibiotic resistance is abundant in agricultural produce, soil, food, water, air and probiotics. • New approaches are being developed to control and reduce antimicrobial resistance., (© 2022. The Author(s).)

Rising tropospheric ozone concentrations can cause rice yield losses and necessitate the breeding of ozone-tolerant rice varieties. However, ozone tolerance should not compromise the resistance to important biotic stresses such as the rice blast disease. Therefore, we investigated the interactive effects of ozone and rice blast disease on nine different rice varieties in an experiment testing an ozone treatment, blast inoculation, and their interaction. Plants were exposed to an ozone concentration of 100 ppb for 7 h per day or ambient air throughout the growth period. Half of the plants were simultaneously infected with rice blast inoculum. Grain yield was significantly reduced in the blast treatment (17%) and ozone treatment (37%), while the combination of both stresses did not further decrease grain yields compared to ozone alone. Similar trends occurred for physiological traits such as vegetation indices, normalized difference vegetation index (NDVI), photochemical reflectance index (PRI), Lichtenthaler index 2 (Lic2), and anthocyanin reflectance index 1 (ARI1), as well as stomatal conductance and lipid peroxidation. Ozone exposure mitigated the formation of visible blast symptoms, while blast inoculation did not significantly affect visible ozone symptoms. Although different genotypes showed contrasting responses to the two types of stresses, no systematic pattern was observed regarding synergies or trade-offs under the two types of stresses. Therefore, we conclude that despite the similarities in physiological stress responses to ozone and blast, the tolerance to these stresses does not appear to be genetically linked in rice., (© 2022. The Author(s).)

Most research in plant chronobiology has been done in laboratory conditions. However, laboratories usually fail to mimic natural conditions and their slight fluctuations, highlighting or obfuscating rhythmicity. High-density crops, such as sugarcane (Saccharum hybrid), generate field microenvironments with specific light and temperature regimes resulting from mutual shading. We measured the metabolic and transcriptional rhythms in the leaves of 4-month-old (4 mo) and 9 mo field-grown sugarcane. Most of the assayed rhythms in 9 mo sugarcane peaked >1 h later than in 4 mo sugarcane, including rhythms of the circadian clock gene, LATE ELONGATED HYPOCOTYL (LHY). We hypothesized that older sugarcane perceives dawn later than younger sugarcane as a consequence of self-shading. As a test, we measured LHY rhythms in plants on the east and the west sides of a field. We also tested if a wooden wall built between lines of sugarcane plants changed their rhythms. The LHY peak was delayed in the plants in the west of the field or beyond the wall; both shaded at dawn. We conclude that plants in the same field may have different phases resulting from field microenvironments, impacting important agronomical traits, such as flowering time, stalk weight and number., (© 2021 The Authors. New Phytologist © 2021 New Phytologist Foundation.)

Background: Stevioside (STE) is a widely used sweetener. Despite the fact that chickens are insensitive to sweetness, dietary STE supplementation could increase the feed intake of broiler chickens. Stevioside might regulate the feeding behavior through functional mechanisms other than its high-potency sweetness. The present study was aimed to elucidate the potential sweetness-independent mechanism of an STE-induced orexigenic effect using the broiler chicken and considering the hypothalamic transcriptome profile and gut microbiome., Results: The analysis of RNA-Seq identified 398 differently expressed genes (160 up-regulated and 238 down-regulated) in the hypothalamus of the STE-supplemented group compared with the control group. Cluster analysis revealed several appetite-related genes were differentially expressed, including NPY, NPY5R, TSHB, NMU, TPH2, and DDC. The analysis of 16S rRNA sequencing data also indicated that dietary STE supplementation increased the relative abundance of Lactobacillales, Bacilli, Lactobacillus, and Lactobacillaceae. Meanwhile, the proportion of Ruminococcaceae, Lachnospiraceae, Clostridia, and Clostridiales was decreased after dietary supplementation with STE., Conclusion: Dietary STE supplementation promoted feed intake through the regulation of the hypothalamic neuroactive ligand-receptor interaction pathway and the alteration of intestinal microbiota composition. This study provides valuable information about the sweetness-independent mechanism of the STE-induced orexigenic effect using the broiler chicken (which is insensitive to sweetness) as the animal model. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

High temperature environment causes reduction in productivity in broilers by disrupting the intestinal barrier function. This study aimed to investigate the protective effects of dietary betaine on intestinal barrier function and cecal microbial community in indigenous broilers (Huaixiang chickens) exposed to high temperature environment. A total of 144 5-week-old male broilers (average initial body weight of 401.62 ± 9.51 g) were randomly allocated to three treatments for 10 weeks feeding trial; each treatment contained six replicates with eight birds per replicate. The three treatments included normal temperature control group (NT, fed basal diet, 26 ± 1 °C), high temperature control group (HT, fed basal diet, 32 ± 1 °C for 8 h/day), and HT group supplemented 1000 mg/kg betaine (HTB). The results showed that high temperature environment reduced the Occludin, Claudin-4, and ZO-1 expressions in duodenal mucosa (P < 0.05). Dietary betaine improved the Claudin-4 and ZO-1 expressions of duodenal mucosa (P < 0.05). In jejunal mucosa, HT group had lower Occludin, Claudin-1, Claudin-4, and ZO-1 expressions than NT group (P < 0.05). Compared with HT group, HTB group had higher Occludin and ZO-1 expression (P < 0.05). In ileal mucosa, the relative mRNA expression of ZO-1 in HT group was lower than those in NT group (P < 0.01), and dietary betaine (HTB group) improved ZO-1 expression compared with HT group (P < 0.05). Based on the results of 16S rRNA sequencing, the enriched and dominant microbials in NT group are Epsilonbacteraeota, Bacteroidetes, and Gammaproteobacterial, the enriched and dominant microbial in HT group is Muribaculaceae, and Firmicutes is the enriched and dominant microbial in HTB group. Taken together, the findings revealed that dietary betaine improved the intestinal barrier function and cecal microbial community in indigenous broilers under high ambient temperature.

An earlier onset of regrowth after snow disappearance can enable wheat cultivars to avoid the hotter grain-filling period, without the need for early sowing in snowy regions. A blackened snow surface easily accelerates snow melting by absorbing solar radiation. In this study, we compare the yield components associated with snowmelt acceleration over 4 years and in 2 locations (Sapporo, SP, and Memuro, MM) in Japan, which exhibit contrasting autumn and spring climates. Early snow melting by snow-blackening accelerated wheat growth in MM by a maximum of 4 days for heading and 3 days for anthesis. Moreover, accelerating wheat phenological growth improved the grain yield in MM in 2016. This is because wheat plants were less likely to experience the localised cool and rainy weather that typically occurs during anthesis in mid-June. Early anthesis would decrease the likelihood that wheat plants experiencing lower sunlight intensity during the grain-filling period owing to exposure to rainy weather. However, warmer autumn conditions in SP likely hindered the development of high-level cold resistance in overwintering wheat. Accelerating snowmelt is one possible tool for mitigating the fluctuations in regional wheat production; however, the effectiveness of snow-blackening depends on the regional climate.

CO 2 emissions tend to increase more rapidly in underdeveloped economies as compared to developed countries mainly in China, India, and Asia. One of the aspects that accounts for the increasing CO 2 emissions is urbanization (UR) and it is increasing all over the world particularly in Asian and African regions. The present study examines the impact of energy use and UR on carbon emissions over the period 1995 to 2018 while using the extended STIRPAT model for Asian countries. Panel co-integration techniques and Granger causality test are applied on selected variables. FMOLS and DOLS methods are also applied to check for robustness. Findings confirm the presence of long-run co-integration among variables. The outcomes propose that energy consumption and UR have positive impact on CO 2 emissions and output. Outcomes also reveal that financial development (FD) has negative effect on emissions of CO 2 but positive effect on economic growth. Results of Granger causality technique indicate that long-run causality association exists among emissions of CO 2 , economic growth, and UR. In the short run (SR), bidirectional causal relationship has been found between trade openness and FD.

The ability to synthesize particular steviol glycosides (SvGls) was studied in Stevia rebaudiana Bertoni hairy roots (HR) grown in the light or in the dark under the influence of different osmotic active compounds. Manipulation of culture conditions led to changes in the morphology and growth rate of HR, as well as to an increase in oxidative stress manifested as an enhancement in endogenous hydrogen peroxide concentration in the cultured samples. The highest level of H 2 O 2 was noted in HR cultured under light or in the medium with the highest osmotic potential. This correlated with the highest increase in the expression level of ent-kaurenoic acid hydroxylase, responsible for the redirection of metabolic route to SvGls biosynthesis pathway. An analysis of transcriptional activity of some UDPglucosyltransferase (UGT85c2, UGT74g1, UGT76g1) revealed that all of them were upregulated due to the manipulation of culture conditions. However, the level of their upregulation depended on the type of stress factor used in our experiment. Analysis of SvGls content revealed that HR grown under all applied conditions were able to synthesize and accumulate several SvGls but their concentration differed between the samples across the different conditions. The level of rebaudioside A concentration exceeded the content of stevioside in HR in all tested conditions. Concomitantly, the presence of some minor SvGls, such as steviolbioside and rebaudioside F, was confirmed only in HR cultured in the lowest osmotic potential of the medium while rebaudioside D was also detected in the samples cultured in the media supplemented with NaCl or PEG.Key Points● Several steviol glycosides are synthesized in hairy roots of S. rebaudiana.● Light or osmotic factors cause enhancement in oxidative stress level in hairy roots.● It correlates with a significant increase in the level of KAH expression.● UGTs expression and steviol glycosides content depends on culture conditions.

The causes of the species richness of tropical trees are poorly understood, in particular the roles of ecological factors such as soil composition. The nickel(Ni)-hyperaccumulating tree genus Geissois (Cunoniaceae) from the South-west Pacific was chosen as a model of diversification on different substrates. Here, we investigated the leaf element compositions, spatial distributions and phylogeny of all species of Geissois occurring on New Caledonia. We found that New Caledonian Geissois descended from a single colonist and diversified relatively quickly into 13 species. Species on ultramafic and nonultramafic substrates showed contrasting patterns of leaf element composition and range overlap. Those on nonultramafic substrates were largely sympatric but had distinct leaf element compositions. By contrast, species on ultramafic substrates showed similar leaf element composition, but occurred in many cases exclusively in allopatry. Further, earlier work showed that at least three out of these seven species use different molecules to bind Ni. Geissois qualifies as a cryptic adaptive radiation, and may be the first such example in a lineage of tropical forest trees. Variation in biochemical strategies for coping with both typical and adverse soil conditions may help to explain the diversification and coexistence of tropical forest trees on similar soil types., (© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.)

We quantified the biomass allocation patterns to leaves, stems and roots in vegetative plants, and how this is influenced by the growth environment, plant size, evolutionary history and competition. Dose-response curves of allocation were constructed by means of a meta-analysis from a wide array of experimental data. They show that the fraction of whole-plant mass represented by leaves (LMF) increases most strongly with nutrients and decreases most strongly with light. Correction for size-induced allocation patterns diminishes the LMF-response to light, but makes the effect of temperature on LMF more apparent. There is a clear phylogenetic effect on allocation, as eudicots invest relatively more than monocots in leaves, as do gymnosperms compared with woody angiosperms. Plants grown at high densities show a clear increase in the stem fraction. However, in most comparisons across species groups or environmental factors, the variation in LMF is smaller than the variation in one of the other components of the growth analysis equation: the leaf area : leaf mass ratio (SLA). In competitive situations, the stem mass fraction increases to a smaller extent than the specific stem length (stem length : stem mass). Thus, we conclude that plants generally are less able to adjust allocation than to alter organ morphology., (© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.)