Harnessing Phytohormones: Advancing Plant Growth and Defence Strategies for Sustainable Agriculture.

Phytohormones, pivotal regulators of plant growth and development, are increasingly recognized for their multifaceted roles in enhancing crop resilience against environmental stresses. In this review, we provide a comprehensive synthesis of current research on utilizing phytohormones to enhance crop productivity and fortify their defence mechanisms. Initially, we introduce the significance of phytohormones in orchestrating plant growth, followed by their potential utilization in bolstering crop defences against diverse environmental stressors. Our focus then shifts to an in-depth exploration of phytohormones and their pivotal roles in mediating plant defence responses against biotic stressors, particularly insect pests. Furthermore, we highlight the potential impact of phytohormones on agricultural production while underscoring the existing research gaps and limitations hindering their widespread implementation in agricultural practices. Despite the accumulating body of research in this field, the integration of phytohormones into agriculture remains limited. To address this discrepancy, we propose a comprehensive framework for investigating the intricate interplay between phytohormones and sustainable agriculture. This framework advocates for the adoption of novel technologies and methodologies to facilitate the effective deployment of phytohormones in agricultural settings and also emphasizes the need to address existing research limitations through rigorous field studies. By outlining a roadmap for advancing the utilization of phytohormones in agriculture, this review aims to catalyse transformative changes in agricultural practices, fostering sustainability and resilience in agricultural settings.

Mating Disruption or Mass Trapping, Compared With Chemical Insecticides, for Suppression of Chilo suppressalis (Lepidoptera: Crambidae) in Northeastern China.

Asiatic rice borer, Chilo suppressalis (Walker), larvae cause extensive crop losses worldwide. Because chemical control is problematic, and sex pheromone applications are a valuable management tactic in China, judicious timing of a minimal density of pheromone dispensers is important in developing a cost-effective C. suppressalis IPM program. During June-October in 2011, 20, 30, 40, and 50 dispensers per hectare for mass trapping, and 200, 300, 400, and 500 dispensers per hectare for mating disruption were placed in northeastern China rice fields. Based on those results, only the two highest mass trapping densities were used in 2012-2013. The 40, 50, and 500 dispenser densities reduced egg masses to <2.0 per 100 tillers, compared with >9.5 in the insecticide-treated plots in 2011-2013. The reduced oviposition resulted in >85% reduction of larval damage, which was comparable with the currently used insecticides, dimethoate and deltamethrin (0.35 kg/ha), which gave no egg reduction, but ≍80 and 89% reduction in larval damage. The 40 and 500 densities are recommended to Chinese rice farmers for mass trapping and mating disruption programs, respectively.

Defense strategies and associated phytohormonal regulation in Brassica plants in response to chewing and sap-sucking insects.

Plants have evolved distinct defense strategies in response to a diverse range of chewing and sucking insect herbivory. While chewing insect herbivores, exemplified by caterpillars and beetles, cause visible tissue damage and induce jasmonic acid (JA)-mediated defense responses, sucking insects, such as aphids and whiteflies, delicately tap into the phloem sap and elicit salicylic acid (SA)-mediated defense responses. This review aims to highlight the specificity of defense strategies in Brassica plants and associated underlying molecular mechanisms when challenged by herbivorous insects from different feeding guilds (i.e., chewing and sucking insects). To establish such an understanding in Brassica plants, the typical defense responses were categorized into physical, chemical, and metabolic adjustments. Further, the impact of contrasting feeding patterns on Brassica is discussed in context to unique biochemical and molecular modus operandi that governs the resistance against chewing and sucking insect pests. Grasping these interactions is crucial to developing innovative and targeted pest management approaches to ensure ecosystem sustainability and Brassica productivity.

Phylogenetic relationships and biological features reveal that male Ostrinia furnacalis (Lepidoptera: Crambidae) in Northeast China can be categorized into postmedial line-based clades.

Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae), often called the Asian corn borer, is a complicated pest because of its complex biological features, such as its adult dynamics, host choice, and life span. This complexity has been causing difficulties in both pest forecasting and control for more than 60 years. One likely explanation for this complexity is that O. furnacalis has several varieties that vary based on some specific features. During 2015-2017, postmedial line-based varieties of male O. furnacalis were identified as distinct clades (I, II, and III), which were then compared based on COI gene sequences, male sacculus construction, life span, male dynamics, and host preference. The results showed that: (1) clades II and III were more closely related to each other than Clade I, because they both completed two generations per year, more were captured in 2016 or fewer were captured in 2015, and they were more closely related according to phylogenetic inference; (2) all three clades shared some features, such as life spans under various rearing conditions, similar dynamic trends, and three teeth on the male sacculus; and (3) all three clades were significantly different from O. nubilalis based on genetic sequences, postmedial line pattern of the forewing, and sacculus construction. Overall, if O. furnacalis is categorized into clades, the species' features are likely to be a combination or mixture of the features of each individual clade. Our findings help explain the biological complexity of O. furnacalis. Future investigations on each individual clade are essential for improving forecasting and control of this pest.

Sex Pheromone Dosages and Release Point Densities for Mating Disruption of Ostrinia furnacalis (Lepidoptera: Crambidae) in NE China Corn Fields.

Mating disruption of Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae) with its sex pheromone has not been commonly used in NE China due to a lack of information about optimal sex pheromone dosages and the density of release points required in the field. During 2014-2016, first, the two active pheromone ingredients were evaluated in the laboratory alone at ca. 2.5-5.0 mg, or in combination at 0.2-6.0 mg, to disrupt male O. furnacalis mating behaviors. Then, mating disruption areas, with radii of <8.0 m, were determined with those same dosages in corn, an orchard, and soybean fields by comparing male captures in sentinel traps in the control plots with those in corresponding disruption treatments. Finally, 6.0 (F30) and 0.2 mg (Fs) dosages were used in fields at 20-640 and 200-6,400 release points/ha. We found that ≧6.0 mg of the binary pheromone mixture, or ca. 5.0 mg of either of the two single components, completely disrupted mating behaviors, and F30 of the binary mixture provided a 200-m2 disruption area, with at least 50% capture reductions. At a density of 60-640 and 600-6,400 points/ha in a corn field, F30 and Fs dosages provided >90% mating disruption, leaf protection, and ear protection. The dispenser densities and inverse male catches in traps tended to follow a noncompetitive mechanism of mating disruption. Since 85% disruption of mating with 200-400 0.02 mg release points/ha was obtained, that level is recommended as the choice in future NE China O. furnacalis IPM programs.

Captures of Ostrinia furnacalis (Lepidoptera: Crambidae) With Sex Pheromone Traps in NE China Corn and Soybeans.

Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae), commonly referred to as the Asian corn borer, is the most important corn pest in Asia. Although capturing males with pheromone traps has recently been the main monitoring tool and suppression technique, the best trap designs remain unclear. Commercially available Delta and funnel traps, along with laboratory-made basin and water traps, and modified Delta traps, were evaluated in corn and soybean fields during 2013-2014 in NE China. The water trap was superior for capturing first-generation O. furnacalis (1.37 times the Delta trap). However, the basin (8.3 ± 3.2 moths/trap/3 d), Delta (7.9 ± 2.5), and funnel traps (7.0 ± 2.3) were more effective than water traps (1.4 ± 0.4) during the second generation. Delta traps gave optimal captures when deployed at ca. 1.57 × the highest corn plants, 1.36× that of average soybean plants, and at the field borders. In Delta traps modified by covering 1/3 of their ends, captures increased by ca. 15.7 and 8.1% in the first and second generations, respectively. After 35 d in the field, pheromone lures were still ca. 50% as attractive as fresh lures, and retained this level of attraction for ca. 25 more days. Increased captures (first and second generation: 90.9 ± 9.5%; 78.3 ± 9.3%) were obtained by adding a lure exposed for 5 d to funnel traps baited with a 35-d lure.

Mass trapping Popillia quadriguttata using Popillia japonica (Coleoptera: Scarabaeidae) pheromone and floral lures in northeastern China.

Popillia quadriguttata (F.) has caused extensive damage to ≍20 families and 25 species of plants in Asia, especially in China and Korea. Adult feeding causes serious damage to soybean leaves, and larvae develop on the roots of soybean, turf, and horticultural crops. As Japanese beetle (Popillia japonica Newman) lures have been used for trapping P. quadriguttata in a previous study, mass trapping this pest with various densities of the Japanese beetle pheromone, Japonilure, and floral lure, alone and in combination, were carried out during 2012-2013 in a northeastern China soybean field. Mass trapping in 2012 with Japonilure gave the best results with 72 and 75% adult and larval reduction, respectively. In 2013, mass trapping (30 traps per hectare) with Japonilure, floral lure, or the combination resulted in a 93, 70, and 74% reduction of adults trapped, and a 90, 77, and 93% reduction of overwintering larvae, respectively. In addition, field tests showed that almost twice as many beetles approached the lure combination compared with the floral lure alone, and the pheromone residual was ≍80% of the initial dosage after 30 d. Because reduction of overwintering larvae is the most critical parameter indicating treatment efficacy, the results here indicate that the lure or lure combinations can be recommended for use by Chinese soybean farmers.

Use of pheromone timed insecticide applications integrated with mating disruption or mass trapping against Ostrinia furnacalis (Lepidoptera: Pyralidae) in sweet corn.

Mating disruption and mass trapping of Ostrinia furnacalis (Génuéé), often called the Asian corn borer, were incorporated with insecticides to reduce pesticide use. Pesticides alone are often ineffective owing to problems in timing applications before the larvae enter the protection of corn stalks. In addition, overuse of insecticides has caused environmental contamination and concerns about consumer health. In 2010, 15 insecticides were compared with mating disruption or mass trapping at various dispenser (disp.) densities for reducing egg masses, trap captures, and ear damage. Mass trapping with 30 and 40 disp./ha, mating disruption with 300 disp./ha, or endosulfan, chlorpyrifos, and monosultap (0.55, 0.35, and 0.55 kg/ha, respectively) gave ≍50% ear protection. In 2011, an insecticide alone, no treatments, pheromone alone, and pheromone + insecticide were examined. The same insecticides in combination with mating disruption or mass trapping at ≧200 or≧20 disp./ha gave >90% ear protection even when chemical applications were reduced to 1 from 3, and the rates were reduced 50-75%. Pheromone dispensers contained >50% of their initial load 30 d after exposure.

The chinese (cantonese) montreal cognitive assessment in patients with subcortical ischemic vascular dementia.

BACKGROUND: Subcortical ischemic vascular dementia (SIVD) has been proposed as the most frequent subtype of vascular cognitive impairment. The aim of this study was to evaluate the psychometric properties of the Chinese (Cantonese) Montreal Cognitive Assessment (CC-MoCA) in patients with SIVD in the Guangdong Province of China. METHODS: 71 SIVD patients and 60 matched controls were recruited for the CC-MoCA, Mini Mental State Examination and executive clock drawing tasks. Receiver-operating characteristic curve analyses were performed to determine optimal sensitivity and specificity of the CC-MoCA total score in differentiating mild vascular dementia (VaD) patients from moderate VaD patients and controls. RESULTS: The mean CC-MoCA scores of the controls, and mild and moderate VaD patients were 25.2 ± 3.8, 16.4 ± 3.7, and 10.0 ± 5.1, respectively. In our study, the optimal cutoff value for the CC-MoCA to be able to differentiate patients with mild VaD from controls is 21/22, and 13/14 to differentiate mild VaD from moderate VaD. CONCLUSION: The CC-MoCA is a useful cognitive screening instrument in SIVD patients.