Annals of Applied Biology最新文献

This study contributes to the improvement of biocontrol strategies, in particular, to develop biological formulations based on microbial consortia. The competitive ability of a microbial species within a consortium is influenced by several factors, such as growth and sporulation rates, niche overlap and interactions with environmental conditions. New strains of Penicillium rubens, P. frequentans and Epicoccum nigrum were isolated from various areas and times of the year. The in vitro effect of temperature and pH on growth and sporulation of each potential antagonist, its metabolism and biocontrol efficacy were evaluated and compared to the reference strains previously identified as biocontrol agents: P. rubens (PO212), P. frequentans (Pf909) and E. nigrum (EPI282). All of the isolates exhibited better growth and sporulation rates at 22°C than at 10°C, for P. rubens and P. frequentans isolates at pH 5.5 but for E. nigrum isolates at pH 8. Only some isolates of P. rubens maintained this maximum sporulation level at pH 8 and 22°C, being significantly higher than the reference strain PO212 under these conditions. Some isolates outperformed the reference strain EPI282 in growth at 22 and 10°C, and pH 5.5 and pH 8. No isolate exhibited better growth and sporulation than Pf909 at both pH and temperature levels, nor better sporulation than EPI282. Ten isolates of P. rubens controlled tomato wilt, but only five of them showed a significantly higher level compared to the reference strain PO212. Only three isolates of these had a niche overlap index (NOI) lower than 0.9 with the tested compounds, indicating that these three P. rubens isolates could have a sufficiently different ecological niche from PO212, and that the other six could compete with PO212; to benefit from their higher control ability, they had to be used individually. Ten isolates of P. frequentans showed a similar level of disease control compared to the reference strain Pf909, and two of them had a NOI of <0.9 with almost the carbohydrate, amine and amino acids tested, indicating that both might have an ecological niche sufficiently different from Pf909. Among the 17 new isolates of E. nigrum able to control cherry rot, only five of them showed a significantly higher level compared to the reference strain EPI282, but only four of them had a NOI of <0.9 with almost one of the tested compounds. The ability to establish and maintain populations of biocontrol agents and the potential of including new isolates in consortia to improve biocontrol were discussed.

Nilaparvata lugens (Stål) is a serious sucking insect of rice in the world. Temperature significantly alters insect growth, development and reproduction parameters. The present study determines the required thermal constants and their effect on the life table parameters of N. lugens, focusing on the impact of temperature. Temperature-dependent linear and non-linear developmental rates, stage-specific mortality and fecundity model functions were fitted at five constant temperature regimes (18–34°C). The Insect Life Cycle Modelling (ILCYM) software was used to fit non-linear equations and to establish an overall phenology model to simulate life table parameters for each constant temperature. The lower temperature development thresholds (LTT) and thermal constants (k) were identified for each developmental stage from egg to adult and estimated from a linear function. At constant temperatures between 18 and 34°C, the developmental duration of eggs and nymphs shortens with higher temperatures, with optimal development observed between 22 and 30°C. Similarly, the maximum fecundity was observed at 26°C, and life table parameters were calculated through stochastic simulations. Life table parameters indicated higher intrinsic growth rates (r_m) and net reproductive rate (R₀) at 26 and 30°C. Additionally, the models were validated with observed and simulated values. Life table parameters, mortality and developmental time were similar to predicted values. The study's findings will help with risk assessment in the context of climate change scenarios for this pest of rice. Further, this study will help devise monitoring strategies against this pest and develop a decision support system for implementation in rice-integrated pest management.

Plants, as sessile organisms, are continuously exposed to one or multiple biotic and abiotic stresses, including the combination of drought and metals, which can severely reduce plant growth. Since this combination has recently emerged as an area of research, this review gathered, for the first time, the available data on the joint impacts of drought and metals in several aspects of plant physiology. Throughout this review, the effects of this stress combination on key plant physiological processes such as photosynthesis, nitrogen metabolism, and redox status were discussed, highlighting the synergistic and antagonistic impacts of one stress on the other. The hormetic effects of metals over drought were also discussed. Furthermore, focus was also placed on how these two stressors impact DNA and hormonal balance. Finally, a mechanistic overview, suggesting new lines of research to address gaps in the understanding of the effects of drought and metals on plant physiology, was drawn. This knowledge is pivotal for the development of effective strategies to mitigate the impact of this combined stress, offering a pathway towards increased plant resilience in an ever-changing environment.

Rice leaf folder, Cnaphalocrocis medinalis is a serious pest of rice and causes 30%–80% yield losses in epidemic outbreak resulting in 0.1–0.27 lakhs of rupees monetary losses per hectare in India. Insecticides are commonly employed to control this pest, but their use often escalates production costs and fosters pesticide resistance. Identifying insect-resistant rice genotypes and their resistance mechanisms is crucial for successful pest management. New sources of resistance providing long-lasting protection against leaf folder can be identified by studying the morphobiochemical characteristics of different rice genotypes. This study explored the role of various morphological traits of certain genotypes that confer resistance. Different biochemical constituents such as soluble protein, phenol, total soluble sugar and enzymes, namely peroxidase, polyphenol oxidase and catalase were assessed spectrophotometrically in all infested and uninfested genotypes and in standard resistant (TKM6) and susceptible (TN1) check genotypes. Leaf folder damage was negatively correlated with plant height and leaf length, while leaf width association was positively correlated. Among the different plant metabolites analysed, total soluble sugar and soluble protein showed positive correlation with leaf folder damage, conversely phenol and antioxidative enzymes showed negative correlation. When rice genotypes were exposed to leaf folder larval feeding, they exhibited defence responses characterized by reduction in the level of sugars and proteins, accumulation of phenolic compounds and upregulation of antioxidative enzymes. This study emphasized the significance of morphobiochemical characteristics in rice resistance mechanisms against leaf folder. By leveraging these traits, new resistant rice germplasms against leaf folder can be developed.

Stubby root nematodes (SRN)—(Trichodorus and Paratrichodorus spp.) are economically important plant parasitic nematodes (PPNs) in east England and have been reported to cause up to 50% root yield reduction in sugar beet (Beta vulgaris). The banning of nematicides such as Vydate (oxamyl) due to environmental concerns limits the management options available to farmers for the management of this nematode. Cover crops (CCs) present a practical option for farmers to manage nematodes whilst enhancing other soil properties such as structure, organic matter content and soil biodiversity, which contributes to the overall soil health. This study evaluated the population dynamics of SRN in field rotations with cover crops. The effect of cover cropping on the yield and quality of follow-up crop, sugar beet, was also evaluated. Field experiments were initiated at two sites in England: Bury St Edmunds, Suffolk (site 1) and Docking, Norfolk (site 2). The cover crops evaluated were—Indian mustard (Brassica juncea), oilseed radish (Raphanus sativus), daikon radish (Raphanus sativus var. longipinnatus), Festuca-lolium hybrid grass (Festulolium loliaceum) with endophyte (E+) and without (E−), Italian rye grass (Lolium multiflorum), phacelia (Phacelia tanacetifolia) and opium poppy (Papaver somniferum). At site 1, plots drilled with brassica cover crops, Indian mustard and oilseed radish, had significantly lower SRN reproduction factor (Rf) (p < .05) compared to the fallow control and daikon radish. In site 2, plots drilled with the cover crops—Italian rye grass, Indian mustard, grass without endophyte (E−) or left fallow and undisturbed had a significantly higher Rf (p < .05) compared to plots with phacelia, opium poppy, and disturbed or sterile fallows. Sugar beet root fanging (%) and root soil tare (%) were lower in plots that had lower SRN reproduction, that is, phacelia, opium poppy, sterile fallow, and disturbed fallow. Environmental variables such as rainfall and soil temperature also influenced SRN densities at different sampling points where SRN increased with increasing rain and decreasing soil temperatures. Results from this study indicate that under field conditions the population dynamics of SRN are influenced by multiple factors such as the host status of the CCs grown, weed occurence which serve as alternative hosts as SRN are polyphagous in nature, soil temperature, rainfall, and soil disturbance. It was also clear that multiplication rate of SRN in CCs such as phacelia and opium poppy was lower despite SRN being able to multiply in all cover crops tested in this study.

Fulfilling climate change mitigation goals will require increased planting of bioenergy crops. Miscanthus is a versatile biomass crop suitable for bioenergy production and bio-products and is expected to form a large part of the bioenergy mix. Reduced impact field preparation and crop establishment are needed to align with sustainable agricultural policies and preserve soil carbon stocks. However, the impact of conservation tillage methods on the root growth of Miscanthus, with implications for establishment, plant resilience and carbon cycling, is currently unknown. Therefore, in this study, we use in-situ minirhizotrons to capture root growth and turnover (root increase/decrease) during the establishment period for field-grown Miscanthus planted with minimum and no-tillage methods (Min Till and No Till, respectively). It was found that the No Till method resulted in higher root length density (Min Till 0.56 vs. No Till 1.39 [cm cm⁻²] at 30–50 cm soil depth, for 2-year-old plants in October) and thinner roots in the subsoil (Min Till 14% vs. No Till 60%, roots in the 0–0.4 mm diameter class, 30–50 cm soil depth, for 1 year-old plants in October) providing potential for improved resource acquisition and soil carbon sequestration. Rapid root growth provided a substantial root base in both treatments (Min Till 1195 and No Till 1442 [g dry matter m⁻²], 0–50 cm soil depth, for 1-year-old plants in October) before resources were allocated to developing rhizomes and above-ground growth. For new planting of Miscanthus on former (marginal) grassland, our results demonstrate that using conservation tillage methods is viable in terms of root growth and plant resilience. Additionally, the observed early years root turnover provides insight into carbon inputs to the soil, important for the modelling of early establishment carbon dynamics.

Understanding the growth rate of nestlings is essential for explaining developmental strategies and is particularly important for birds of prey. Given that they have lower reproduction rates than other species, the growth rate could be one of the critical factors determining parental fitness and influencing the individual's condition. Despite variability often resulting from various stress conditions, the growth rate is predictable for given ages of nestlings, as highlighted here. This study investigates the growth dynamics of Bonelli's Eagle (Aquila fasciata) nestlings in the Republic of Cyprus, focusing on 13 biometric variables measured over time. We employed logistic and generalized additive models to analyse growth trajectories and identify predictors of age. Our findings highlight that nestlings achieve maximum growth rates in body mass and tarsus length early in development, followed by primary feathers and wing length. Conversely, head width, beak dimensions, and talon length exhibit slower and more gradual growth. Precisely describing the rate and pattern of growth of individual body components enabled us to develop a tool for predicting age. We found that wing, tarsus, and middle talon lengths are the most reliable predictors of nestling age. The effectiveness test of our predictive model conducted on an independent data set showed that the age estimation error is 1 day. Thus, our research provides a deep insight into the eagles’ developmental patterns while offering practical tools for field studies and conservation efforts.

Orthotospovirus tomatomaculae, formerly tomato spotted wilt virus (TSWV; family Tospoviridae), is one of the most economically important plant viruses worldwide, due in part to its wide host-plant range and global distribution. Since the first outbreaks in the first half of 1900, the TSWV infections have represented a serious threat for several crops, such as tomato, pepper, lettuce, potato, peanut and tobacco, in both open-field and greenhouse farming conditions. TSWV is transmitted in a persistent, propagative manner by thrips vectors belonging to the genera Frankliniella and Thrips. Besides the vector control, the use of resistant cultivars has been one of the most effective management strategies of TSWV disease, at least for tomato and pepper crops. However, the selection pressure has led to the emergence of novel resistance-breaking viral strains which are increasingly responsible for the re-emergence of TSWV outbreaks in several cropping areas. As type species of tospoviruses, TSWV has also been particularly well studied for understanding the structure of the different tospovirus proteins and their roles in replication, infection, thrips transmission and ecological processes. This review aims to consolidate the most recent advances in research on this virus and will form the basis of an updated version of the Association of Applied Biologists description of plant viruses for TSWV.

Using organic wastes for biochar production represents an innovative approach to waste management, facilitating safe residue disposal while producing a soil amendment by-product. The characteristics of biochar strongly depend on the chemical composition of the feedstock utilised in its production. Consequently, even within the same agroecosystem, different types of biochar may produce varying effects on soil chemistry and biology. In a greenhouse experiment, we assessed the impact of poultry manure and peanut shell biochars on soil chemical properties and their effects on microbial community structure, abundance, diversity and functions analysed through biochemical and molecular approaches. Thus, a two-factor experimental design was established, considering biochar type (poultry manure and peanut shell biochars) and rate (0%, 1%, and 3% w/w). Our findings highlighted that the intrinsic properties of biochar significantly influenced its ability to induce changes in the analysed variables. Poultry manure biochar exhibited greater efficacy in increasing soil pH and EC, simultaneously enhancing fungal and total biomasses. Meanwhile, peanut shell biochar increased N content and decreased C/N, slightly impacting fungal and total biomasses. The effects of biochars on FAMEs and chemical variables were dose-dependent; the higher the application rate, the greater the observed effect. Interestingly, different biochar types affected distinct bacterial taxa abundances. Among the dominant Phyla, while poultry manure biochar increased the relative abundance of Chloroflexi and decreased that of Proteobacteria, peanut shell biochar increased Acidobacteria and reduced Firmicutes phyla. The biochar rate did not affect bacterial abundance. Notably, only peanut shell biochar increased bacterial richness. Poultry manure biochar positively impacted functions related to metabolism, whereas the effect of peanut shell biochar was less evident. Our study revealed that the intrinsic characteristics of biochar significantly modulate the structure and functionality of the soil microbial community. Therefore, understanding the inherent characteristics of biochar is crucial to promoting the development of specific groups of soil microorganisms, thus optimising the cycling of essential nutrients.

Engineering Biology in Brazil's transition from oil reliance to bioproduction emphasizes the importance of precision biology in enhancing biodiversity through sustainable agricultural practices. Gene editing can improve food and chemical production, nutritional value, and disease resistance in crops, thus reducing the need for chemical pesticides and unsustainable farming practices. We outline the pivotal role of precision biology in Brazil's transition, highlighting the potential of gene editing to enhance agricultural sustainability. This approach aligns with the United Nations Sustainable Development Goals and benefits from a stable, positive regulatory framework established by the Brazilian Biosafety Committee. Jointly, these advances contribute to global food security while addressing public concerns about safety and ethics.