Annals of Applied Biology最新文献

The diet consumed by adult parasitoids can affect longevity, survival, and fecundity. Honeydew from sap-sucking insects is an abundant food resource in the field; however, artificial diets such as commercial bee honey are often used in lab rearing. The parasitoid Paracentrobia subflava (Girault) (Hymenoptera: Trichogrammatidae) is a natural enemy of Dalbulus maidis (DeLong) (Hemiptera: Cicadellidae). The longevity and survival of P. subflava when fed natural and artificial diets under controlled conditions have not been studied. Further, the fecundity of P. subflava when fed a diet of honey has not been investigated. Therefore, our first objective was to analyse the longevity and survival of P. subflava when fed (1) honeydew of the corn leafhopper D. maidis, (2) honey + water, (3) honey + water + pollen, (4) water, and (5) nothing (control). Our second objective was to evaluate P. subflava fecundity upon exposure to D. maidis eggs, comparing parasitoids fed with honey + water versus controls (no food or water). In the second objective, honey was chosen since it was determined during the first objective to be the optimal food. The longevity of adult parasitoids (laboratory-reared and field-collected) was high when fed on honey and low when fed other diets. The highest longevity was achieved with honey + water: 17 days, while the survival of adult parasitoids was only 3 days for honeydew. Interestingly, fecundity, in terms of the percentage of parasitism and the percentage of emergence, did not differ between parasitoid females that had access to honey + water as a food resource and those that had no food or water.

Agricultural improvements that reduce conventional pesticide use and support environmental aims are a priority. Current approaches develop promising alternative products but meet significant challenges in bringing them to market. This article reports findings of an Association of Applied Biologists event at which delegates from relevant industry sectors discussed the establishment of an effective integrated pest management innovation system linking multiple stakeholders. Interrelated recommendations were agreed upon, focused on structured gap analysis, co-design processes reflecting the complete innovation system, the approval process, application equipment, enhancing grower confidence, integrating knowledge exchange activities, promulgation of public good information and the need for an overarching national action plan and supporting legislation.

Flock health planning has been advocated as part of a wider drive within livestock production for veterinarians and farmers to adopt a prevention-focused approach to veterinary medicine. This approach has, at its core, a cyclical process of assessment, evaluation, action and re-assessment, and is documented, at least in summary, in a health plan (HP). The HP has become a defining pillar of farm quality assurance schemes (QASs), introduced to address calls for greater transparency and accountability in food production. There is limited current information on the attitudes and behaviours surrounding flock HPs in the sheep sector and the barriers to greater involvement in an active process of continual improvement through reflective flock health planning. This study aims to address these issues with reference to the national flock in Northern Ireland. A mixed-methods approach was used to explore farmers' and veterinarians' opinions and behaviours related to QASs and HP, with data obtained through an online scoping questionnaire, semi-structured interviews with 27 farmers and 15 veterinarians, and discussion groups with farmers and veterinarians. No evidence of a positive association between a farm having a HP and implementation of 12 industry-recommended flock health activities was identified using the Fisher's exact test. Farmers reported a reluctance to pay for veterinary advice while some veterinarians reported a lack of time to develop HPs for farmers, and sheep-related work generally. Farmers predominantly saw the HP as a static, physical document, which had limited impact on their management practices, rather than a proactive, reflective and collaborative planning process. Veterinarians tasked with completing HPs felt restricted by limited knowledge of on-farm practices, flock production data and a lack of confidence in the accuracy of on-farm medicine records. This led some to believe that the HPs may fail to address critical issues. A new approach to engage farmers and veterinarians together in active flock health planning needs to be developed. This will need a sustainable delivery plan. Then the focus can be shifted towards ongoing reflective health planning to drive change for the betterment of sheep health and welfare.

The population growth and the regular breakout of Nilaparvata lugens pose a significant risk to rice cultivation. Four different N. lugens biotypes have been identified worldwide, with biotype 4 being the most destructive and prevalent throughout Asia, particularly in India. Therefore, a rice variety with multiple resistance genes/alleles is required for effective management of N. lugens. Hence, 191 rice genotypes collected from various parts of India were evaluated for resistance to N. lugens. Further, SSR markers representing 23 different N. lugens resistant (R) genes were assayed to identify genomic regions associated with resistance. The results of the genetic analysis showed that the average genetic diversity value of all markers was 0.165 and polymorphic information content of 0.145 for all the markers used. The population structure and cluster analysis divided the studied genotypes into three distinct groups, with resistant genotypes grouped separately. These findings were confirmed by the principal coordinate analysis, which categorized resistant genotypes, moderately resistant genotypes, and susceptible genotypes into distinct components. Additionally, 90% of the genetic variation was between individuals of populations and 10% between the populations. Marker-trait association study through mixed linear model and generalized linear model identified six SSR markers such as RM6732 (Bph15), RM314 (Bph6), RM16999 (Bph6), RM7 (QBph3), RM401 (bph4), and RM7102 (Bph1), which were significantly associated with various phenotypic parameters, such as feeding mark, honeydew excretion, percent damage and nymphal survival. The resistant genes identified in these genotypes could help in the marker-assisted rice variety development with durable resistance against N. lugens.

A tomato-infecting virus known as Beet curly top Iran virus (BCTIV) cause a significant disease for tomato plants and several other plant species around the world. Chitosan polysaccharide is a natural biopolymer that has been utilised as an exo-elicitor to enhance plant defence mechanisms against a variety of plant diseases. This study investigates the efficacy of chitosan in combating BCTIV disease on tomato plants and modulating the host–virus interaction under greenhouse conditions. Twenty-four hours before the virus inoculation, tomato plants were sprayed with a protective chitosan solution at different concentrations (0.5, 1, 1.5, and 2 mg/mL). Tomato plants were inoculated with a BCTIV infectious clone using an Agrobacterium-inoculation method. The findings clearly demonstrated a reduction in the severity of the disease in chitosan-treated plants as compared to Mock-plants, with the percentage decreasing from 61.53% to 75.28% in 1.5 mg/mL treated plants and from 9.01% to 28.43% in 0.5 mg/mL treated plants. In addition, the utilisation of chitosan has the potential to deactivate the accumulation of BCTIV within the host tissues. The virus accumulation was greatly alleviated in 1, 1.5, and 2 mg/mL-treated plants by 71.29%, 90.11%, and 93.14%, respectively, and over the mock plants. Furthermore, it was found that chitosan applied at all tested concentrations increased the relative expression and mRNA accumulation of genes related to resistance, including the pathogenesis-related protein gene PR-1, the HSP90 gene, and the AGO2a antiviral gene. These genes reached their maximum by 22.9-, 12.93-, and 4.44-fold increases, respectively, over the untreated control. According to gas chromatography–mass spectroscop (GC-MS) fractionation profile, chitosan increased 28 bioactive metabolic components, such as n-hexadecanoic acid, heptanone, 1,2-dimethylbenzene, dicarboxylic acid, and cis-11-octadecenoic acid methyl-ester, to improve metabolic pathways. Results reported here revealed that foliar application of chitosan decreases the rate of the disease severity and virus accumulation in BCTIV-infected tomato plants. This effect is associated with increased gene expression and defence-related factors, enhancing tomato resistance to BCTIV infection. Consequently, chitosan treatments could be part of an integrated approach for reducing the severity of BCTIV disease in tomato and other host plants.

Penicillium expansum is a fungal pathogen of pome fruit, causing the economically important disease of apple blue mould. The fungus is also important due to its ability to produce the mycotoxin patulin. A strain of Aureobasidium spp. (UC14) was assessed for controlling P. expansum and patulin production in a series of in vitro antibiosis experiments. Volatile and non-volatile metabolites reduced growth of P. expansum on average by 50%. To assess UC14 efficacy on apples in vivo, different concentrations of cellular suspension were assayed. The concentration 1 × 10⁸ cells/mL was the most effective, completely suppressing apple fruits blue mould symptoms. The antagonism of UC14 was further demonstrated by the very low amount of pathogen DNA in treated fruits detected by qPCR. During cold storage, Aureobasidium strain UC14 persisted on fruits and reduced disease severity by 82.5% and 89.8%, for ‘Golden delicious’ and ‘Fuji’ apples, respectively. Aureobasidium strain UC14 reduced patulin on ‘Golden delicious’ and ‘Fuji’ apples by 98.1% and 96.2% with respect to the control, demonstrating good efficacy as a potential biological control agent (BCA), so becoming an interesting candidate for use as BCA in the postharvest phase.

Crambe (Crambe abyssinica Hochst.) is an oilseed crop domesticated in the Mediterranean region that is becoming increasingly important worldwide. Crambe is now considered as an alternative to bioenergy crops and oleochemicals, because of its ability to acclimatise under inhospitable conditions. Despite the interest in the agronomic characteristics and applications of this crop, research on crambe is still scarce and has focused only on production, taking into account the phenological stages of this species. Therefore, a single criterion for quantifying the phenology of the species can be a useful tool for both researchers and growers. In the present study, a proposed scale of the phenological growth stages of crambe was applied according to the BBCH (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie) coding system. The phenological stages were described using the one- and two-digit decimal coding of the BBCH system and corresponded to stage 0: germination; stage 1: leaf development; stage 2: lateral sprout formation; stage 5: inflorescence emergence; stage 6: flowering; stage 8: fruit ripening and stage 9: senescence. Growth stages 3 and 4 (main stem elongation and development of collectable vegetative parts, respectively) have been omitted. Figures have been included to illustrate the main stages, and plant growth has been represented by a technical botanical illustration. The BBCH system has been effective in providing phenological data on crambe, allowing for better growing management of the crop under varying climatic conditions, as well as contributing to the standardisation of research methods on the species.

Sweet potato is grown for its starchy roots in many countries and is widely cultivated in India. This crop is widely acknowledged for its substantial economic and health benefits. However, a comprehensive description of its phenology has not been reported. The phenological growth stages of sweet potato are described here for the first time using the extended Biologische Bundesantalt, Bundessortenamt, and Chemische Industrie (BBCH) scale. Nine primary growth stages have been specifically defined, including germination (0), leaf development (1), main shoot development (2), side shoot development (3), tuber development (4), inflorescence emergence (5), flowering (6), fruit development (7), fruit maturation (8), and senescence (9). The sequential progression of key growth stages has been described according to the phenological development structure and environmental requirements of different phenophases. Because it covers all phenophases related to the vegetative and reproductive stages, the extended BBCH scale is extensively useful for sweet potato cultivation. The extended BBCH scale may also be a useful tool for assessing the potential effects of climate change on crop productivity and fruit quality.

Phenological models serve as a potent tool in management practices and determining flowering time in ornamental crops. Schwab's staging system for development of gladiola that relies on easily identifiable visual characteristics was used in the study to describe the detailed developmental stages and requirement of agrometeorological indices for each stage. The study was conducted with five gladiolus varieties planted at four different times to characterize the varieties for planting time. Plants under September and October plantings completed their phenological development in less time and accumulated fewer agrometeorological indices because of favourable temperature and short day conditions. The phenological model revealed that Punjab Lemon Delight and Punjab Glance could be planted in September as their blooming was delayed by 32 and 17 days, respectively and corm harvesting by 48 and 43 days respectively, when planted in December. The delay in blooming was 18 and 15 days respectively for Punjab Glad 3 and CPG and corresponding values for corm harvesting were 30 and 26 days when planting was done in December indicating that these varieties could be suitable for late planting. White Prosperity could be planted in October or November because when comparing planting in these 2 months, the number of days to bloom and the number of days to corm harvesting were similar.