Annals of Applied Biology最新文献

The pasture legume Trifolium subterraneum ssp. yanninicum L. is waterlogging tolerant, but water-deficit (WD) susceptible. The interactive effect of waterlogged (WL) and WD (soil moisture fluctuation [SMF]) results in a severe stress impact. We studied three diverse ecotypes to identify traits associated with adaptation to SMF. Ecotypes were established in a glasshouse with two treatments imposed at 21 days: well-watered (WW–WW; 80% field capacity [FC]) and WL to WD (WL–WD). For WL–WD, pots were WL for 28 days (Harvest I), and then transitioned to WD (drained to 40% FC) and maintained for 10 days (Harvest II). For shoot relative growth rates (RGR) at Harvest I, WL had relatively little impact, although there was a greater reduction for Ecotype A (80% of WW) than Ecotypes B (92%) and C (87%). However, between Harvests I and II, the impact of WL–WD varied among ecotypes with Ecotype A being less affected (75% of WW–WW) than Ecotypes B (57%) and C (63%). For root RGR at Harvest I, WL resulted in a greater reduction for Ecotype A (52% of WW) than Ecotypes B (77%) and C (74%), while for WL–WD between Harvests I and II, Ecotype A showed a large increase (117% of WW–WW) compared to Ecotypes B (95%) and C (87%). In conclusion, the response to WD following WL varied among ecotypes, which demonstrates contrasting adaptation responses to SMF unrelated to WL tolerance. High yield under WL together with capacity for rapid growth post-WL in a drying soil profile could enhance adaptation to SMF.

Gleditsia sinensis is a species endemic to China, an ecologically economic multipurpose tree with great development potential, which could be used as medicine, food, industrial materials and wood. It is well known that the standardized description of plant development stages according to their phenological characteristics not only is crucial for conduct of various agronomic practices, but also facilitates the exchange of new findings based on the same understanding of the plant. However, a uniform phenology scale of G. sinensis has rarely been reported, despite its expanding plant area and rapid development of this industry over the past few years. Thus, phenological events of G. sinensis were monitored based on the BBCH scale during two consecutive years in this study. Eight of the 10 BBCH stages described in detail by combining numbers and letters based on its species characteristic were accurately recorded, including bud development (0), leaf development (1), shoot development (3), inflorescence emergence (5), flowering (6), pod development (7), maturity of pod (8) and senescence (9). As far as we know, it is the first time that a special phenological rhythm for G. sinensis has been developed using an extended BBCH scale, which not only provides the basis for other basic research, but also assists growers in conducting planting management practices.

Robinia pseudoacacia (black locust), an alien species in Japan, has been commonly planted to rehabilitate degraded land and as a resource for the production of honey. Although very few R. pseudoacacia adult trees are found in established mature forests, the management of R. pseudoacacia is a vital and urgent matter because of astounding growth potential, which negatively affects biodiversity and native vegetation. For this reason, we evaluated the seasonal shade-acclimation capacity of black locusts from the viewpoint of photosynthetic nitrogen use (PNU) and their partitioning. We assessed in situ photosynthetic N use traits of R. pseudoacacia leaves at open sites (relative photosynthetic photon flux density: (rPPFD) > 90%) and shaded sites (rPPFD < 22%) on the forest floor in larch (Larix kaempferi Carr.) plantations. Leaf unfolding started in late May and leaves turned yellow by mid-October just before leaf shedding. Shoot length at open sites was three times longer than at shaded sites. R. psudoacacia at open sites has more the leaflet number of each pinnate compound leaf than shaded sites from mid-August to October, and the size of leaflets at shaded sites was about 20% smaller than it was at the open sites. Leaf mass per area showed (mean ± standard deviation) 40.00 ± 2.14 g m⁻² at the open sites and 22 ± 1.56 g m⁻² at the shaded sites from June to October. The light-saturated photosynthetic rate peaked at 22 μmol m⁻² s⁻¹ at the open sites in July. At the shaded sites, it gradually increased to 7–10 μmol m⁻² s⁻¹ around August, and then decreased at both sites toward zero in mid-October. The total N content during the growth period was 1.60 ± 0.17 g m⁻² at open sites and 1.16 ± 0.15 g m⁻² at shaded sites. Unlike other tree species, N partitioning to photosynthetic organs was not affected by light conditions. These findings suggested R. psudoacacia cannot acclimate to shady conditions.

The modern cultivars of sugarcane (Saccharum spp.) are highly polyploid and accumulate aneuploidies due to their history of domestication, genetic improvement and interspecific hybrid origin involving the domesticated sweet species Saccharum officinarum (‘noble cane’) and the wild Saccharum spontaneum, both with an evolutionary history of polyploidy. The first hybrids were backcrossed with S. officinarum, and selection from progenies in subsequent generations established the genetic basis of modern cultivars. Saccharum genome complexity has inspired several molecular studies that have elucidated aspects of sugarcane genome constitution, architecture and cytogenetics. Herein, we conducted a comparative analysis of the meiotic behaviour of representatives of the parentals S. officinarum and S. spontaneum, and the commercial variety, SP80-3280. S. officinarum, an octoploid species, exhibited regular meiotic behaviour. In contrast, S. spontaneum and SP80-3280 exhibited several abnormalities from metaphase I to the end of division. We reported and typified, for the first time, the occurrence of peri- and paracentric inversions. Using in-situ hybridisation techniques, we were able to determine how pairing association occurred at diakinesis, the origin of lagging chromosomes and, in particular, the mitotic chromosome composition of SP80-3280. Interestingly, S. spontaneum and recombinant chromosomes showed the most marked tendency to produce laggards in both divisions. Future attempts to advance knowledge on sugarcane genetics and genomics should take meiotic chromosome behaviour information into account.

Silicon can increase the natural defence of plants against stresses including herbivorous insects. Silicon dioxide (SiO₂) is one of the forms of silicon, and despite its wide use in the industrial sector, its use in agriculture is still poorly adopted. The aim of this study was to evaluate the effectiveness of foliar application of SiO₂ in inducing defence against Spodoptera frugiperda in soybean. The experiments were conducted in a completely randomised design with four treatments (0%, 1%, 2.5%, and 5% of SiO₂). The effect on cannibalism, biological parameters (mortality, duration of the larval stage, duration of the pupal stage and pupal weight) and wear on the mandible of S. frugiperda were evaluated. The foliar silicon content was also determined. The supply of SiO₂ prolonged the duration of the larval and pupal stages of the S. frugiperda by 0.56 and 0.17 days for each 1% of SiO₂ applied, respectively. The use of SiO₂ at 5% increased the mortality rate of caterpillars in the larval stage by approximately 25%. There was no effect of SiO₂ application on cannibalism and weight of S. frugiperda pupae. There was wear on the caterpillars' jaws in the third and fourth instar at the highest SiO₂ concentration. The application of SiO₂ promoted greater accumulation of silicon in soybean leaves. It is concluded that the foliar application of SiO₂ affects the biological performance of S. frugiperda through the induction of defence in the soybean crop and presents itself as a promising strategy in integrated pest management programmes.

During the past two decades, a high mortality of coconut palms was observed in the coastal areas of Equatorial Guinea. Reportedly, the palm population has been reduced by 60%–70%, and coconut production has decreased accordingly. To identify the cause of the mortality, a survey was carried out in April 2021 in various localities of the coconut belt. Molecular analyses carried out on 16S rRNA and secA genes detected phytoplasma presence in the majority of the samples. Sequencing and BLAST search of the 16S rRNA gene sequences showed >99% identity of the detected phytoplasmas to ‘Candidatus Phytoplasma palmicola’. The RFLP analyses of 16S ribosomal gene using Tru1I and TaqI enzymes led to assign these phytoplasmas to subgroup 16SrXXII-A. In all samples that tested positive, including one from a hybrid coconut palm and two from oil palm the same phytoplasma was identified. The phylogenetic analyses of 16S rRNA and secA genes confirmed respectively 99.98%–100% and 97.94%–100% identity to ‘Ca. P. palmicola’. RFLP analyses using MboII enzyme on the secA gene amplicon differentiated the phytoplasma found in Equatorial Guinea from those present in Ghana and Ivory Coast. The Equatorial Guinean phytoplasma strain resulted to be identical to the strains from Mozambique, confirming the presence of a geographic differentiation among phytoplasma strains in the coastal areas of Western and Central Africa. The identified phytoplasma is different from the ‘Ca. P. palmicola’ strains found in Ghana and Ivory Coast and represents the first identification a 16SrXXII-A strain in Equatorial Guinea and in Central Africa. Strict monitoring and surveillance procedures for early detection of the pathogen are strongly recommended to reduce its impact and further spread in the country and permit the recovery of coconut plantations.

Astragalus membranaceus var. mongholicus (Astragalus) is a perennial medicinal plant belonging to Leguminosae. Its main agronomic and industrial interest is the accumulation of astragaloside IV and calycosin-7-O-β-D-glucoside in roots, two components that play crucial pharmacological roles in the finished pharmaceutical products. Phenological research is a prerequisite for improving the yield quality of cultivated medicinal plants. However, there are no standardized phenological studies on Astragalus. To expand phenotyping knowledge on this medicinal plant, researchers and breeders need a universal scale to describe the development of this plant. This study aims to define the phenological growth stages of Astragalus, based on the existing Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH) scale to provide a standard scale for Astragalus, and grown under temperate conditions of production and climate, proposes a disease and pest control reference. This study was conducted in Inner Mongolia, North China. The existing BBCH scale with a three-digit code was used to define Astragalus's phenological growth codes, supplemented with pictures. Phenological observations were performed twice monthly, based on the developmental stages. The chronology and duration of each stage were also observed and described according to the accumulation of degree days during the growing season. Based on the data obtained, the influence of the average temperature and GDD on the phenophases was evaluated. The phenological description is divided into two principal growth stages: five for vegetative growth (perennating bud, leaf development, formation of branches, main stem elongation and root development), four for reproductive growth (reproductive organ development, flowering, fruit development and fruit maturation), and one for senescence according to the BBCH scale. Seventy secondary growth stages were described within the 10 principal growth stages. Under each secondary growth stage, six mesostages are also taken into account, which contains the distinct patterns of the phenological characteristics in Astragalus varieties and the process of transplanting seedlings. A practical management program for disease and pest control was also proposed by using the BBCH code and the phenological data proposed in this work. Our study presents the first BBCH scale established for Astragalus cultivated in temperate conditions and a chronology of phenological stages based on the accumulation of thermal time, through growing degree day calculation. This work provides a general tool that can be widely used by researchers, breeders, and manufacturers of medicinal materials leading to better agricultural production and scientific communication.

The root-knot nematode Meloidogyne incognita is one of the most damaging plant parasitic nematodes in the world. In this study, the effect of cystatin from Amaranthus hypochondriacus (AhCPI) as a potential control agent for M. incognita was explored. In vitro bioassays demonstrated that AhCPI affects the growth and development of eggs and the infectivity of juveniles (J2) of M. incognita, such as mortality and slower development, showing characteristic tissue damage. Mortality levels were quantified by Probit analysis, estimating LC₅₀s of 1.4 mg/mL for eggs and 0.028 mg/mL for J2. In planta bioassays showed that infected tomato seedlings treated with 0.056 mg/mL of AhCPI showed a 60% reduction in the number of galls, as compared with untreated J2-inoculated seedlings. Under greenhouse conditions, three applications of 10 mL of AhCPI (1.4 mg/mL) in the soil around the stem of M. incognita-infected tomato plants, reduced the number of galls by 93 ± 8%, as compared to the control M. incognita-infected plants. The application of AhCPI to the infected plants increased the yield (10.7%) of harvested tomato fruits, as compared to infected plants. These results show the potential of AhCPI for the control of M. incognita in tomato plants.

High emergency department (ED) pediatric readiness is associated with improved survival in children, but the cost is unknown. We evaluated the costs of emergency care for children across quartiles of ED pediatric readiness. This was a retrospective cohort study of children aged 0-17 years receiving emergency services in 747 EDs in 9 states from January 1, 2012, through December 31, 2017. We measured ED pediatric readiness using the weighted Pediatric Readiness Score (range: 0-100). The primary outcome was the total cost of acute care (ED and inpatient) in 2022 dollars, adjusted for ED case mix and hospital characteristics. A total of 15 138 599 children received emergency services, including 27.6% with injuries and 72.4% with acute medical illness. The average adjusted per-patient cost by quartile of ED pediatric readiness ranged from $991 (quartile 1) to $1064 (quartile 4) for injured children and $1104-$1217 for medical children. The resulting cost differences were $72 (95% CI: -$6 to $151) and $113 (95% CI: $20-$206), respectively. Receiving emergency care in high-readiness EDs was not associated with marked increases in the cost of delivering services.