Vegetable Crops Research Articles

Global Invasion of Thrips parvispinus (Karny) (Thysanoptera: Thripidae) Across Three Continents Associated With Its One Haplotype

ABSTRACTThrips parvispinus (Karny) is an exotic pest that has invaded many regions around the world in the last three decades. It was first detected in Florida in 2020 on ornamental plants (Hoya and Anthurium) in greenhouses and subsequently on ornamental plants in residential landscapes (Gardenia) in 2021. However, its first report on open vegetable field crops (Capsicum) in Florida was in 2022. We conducted field surveys and genetic analysis to answer three questions: (1) Is the population of T. parvispinus that invaded Florida the same as the one that has spread globally in the last few decades? (2) Is the host expansion to Capsicum in Florida a new population or the extension of the existing population reported on ornamental plants? and (3) What are the native and invaded distribution ranges of T. parvispinus? We analysed the genetic variation in the mitochondrial gene cytochrome oxidase I (COI) to address these questions. The global genetic diversity analysis of T. parvispinus revealed 18 haplotypes (populations) worldwide based on available data, but only one population (Hap1) invaded three continents: Africa, Europe, and North America. Based on available data, the highest haplotype diversity was observed in India, suggesting India may be part of the presumed native range (South and Southeast Asian countries) of T. parvispinus. Our survey of retail plant stores across 10 Florida counties indicated that plant trade is the source of T. parvispinus in open vegetable field crops and ornamental landscape plants. The outcome of this study will assist with regulatory and management decisions of T. parvispinus in Florida and elsewhere.

Early detection of verticillium wilt in eggplant leaves by fusing five image channels: a deep learning approach.

As one of the world's most important vegetable crops, eggplant production is often severely affected by verticillium wilt, leading to significant declines in yield and quality. Traditional multispectral disease-imaging equipment is expensive and complicated to operate. Low-cost multispectral devices cannot capture images and cover less information. The traditional approach to early disease diagnosis involves using multispectral disease-imaging equipment in conjunction with machine learning technology. However, this approach has significant limitations in early disease diagnosis, including challenges such as high costs, complex operation, and low model performance. The aim of this study was to combine low-cost multispectral cameras with deep learning technology to detect early stage Verticillium wilt in eggplant effectively. Using the Manual FS-3200T-10GE-NNC multispectral camera to perform multispectral imaging of the leaves of eggplant seedlings at the early infection stage, information fusion was performed on the collected multispectral images, and a five-channel image information fusion model was established. Image information fusion technology was combined with deep learning technology, among which the VGG16-triplet attention model performed the best, achieving a precision of 86.73% on the test set. Model validation on 48- and 72-hour data reached a precision of 75% and 82%, respectively, achieving an early diagnosis of Verticillium wilt. This highlighted the potential of multispectral cameras for early disease detection. In this study, we successfully developed a method for the non-destructive detection of the early stages of eggplant wilt disease by combining multispectral imaging technology with deep learning algorithms. While ensuring high accuracy, this method significantly reduces the cost of experimental equipment. The application of this method can reduce the cost of agricultural equipment and provide a scientific basis for agricultural production practices, helping to reduce losses caused by diseases.

Isolation and identification of antifungal, antibacterial and nematocide agents from marine bacillus gottheilii MSB1.

Pathogenic fungi employ numerous strategies to colonize plants, infect them, reduce crop yield and quality, and cause significant losses in agricultural production. The increasing use of chemical pesticides has led to various ecological and environmental issues, including the emergence of resistant weeds, soil compaction, and water pollution, all negatively impacting agricultural sustainability. Additionally, the extensive development of synthetic fungicides has adverse effects on animal and human health, prompting the exploration of alternative approaches and green strategies for phytopathogen control. Microorganisms living in sponges represent a promising source of novel bioactive secondary metabolites, potentially useful in developing new nematicidal and antimicrobial agents. This study focuses on extracting bioactive compounds from endosymbiotic bacteria associated with the marine sponge Hyrtios erect sp. (collected from NIOF Station, Hurghada, Red Sea, Egypt) using various organic solvents. Bacillus sp. was isolated and identified through 16S rRNA gene sequencing. The biocidal activity of Bacillus gotheilii MSB1 extracts was screened against plant pathogenic bacteria, fungi, and nematodes. The n-butanol extract showed significant potential as a biological fungicide against Alternaria alternata and Fusarium oxysporum. Both n-hexane and ethyl acetate extracts exhibited negative impacts against the plant pathogenic bacteria Erwinia carotovora and Ralstonia solanacearum, whereas the n-butanol extract had a positive effect. Regarding nematicidal activity, ethyl acetate and n-butanol extracts demonstrated in-vitro activity against the root-knot nematode Meloidogyne incognita, which causes serious vegetable crop diseases, but the n-hexane extract showed no positive effects. The findings suggest that bioactive compounds from endosymbiotic bacteria associated with marine sponges, particularly B. gotheilii MSB1, hold significant potential as alternative biological control agents against plant pathogens. The n-butanol extract, in particular, displayed promising biocidal activities against various plant pathogenic fungi, bacteria, and nematodes. These results support further exploration and development of such bioactive compounds as sustainable, environmentally friendly alternatives to synthetic pesticides and fungicides in agricultural practices.

Evaluation of F1 hybrids against root knot nematode (<i>Meloidogyne incognita</i>) resistance in Brinjal (<i>Solanum melongena</i> L.)

Brinjal is one of the most important commercial solanaceous vegetable crops. Root knot nematodes cause severe yield losses in brinjal both in open and poly house conditions. Host plant resistance is considered to be a viable solution and cost-effective method to manage the root knot nematodes. Ten genotypes along with their nineteen F1 hybrids were screened for resistance to root knot nematode and biochemical basis of resistance was assessed. Two F1 hybrids viz., IIHR-824 x VI046101, IIHR-824 x IIHR-766, parents viz., IIHR-824 and VI046103 were found to be resistance to M. incognita with gall index/ egg mass index of 1. Three F1 hybrids, IIHR-824 x IIHR-356, IIHR-824 x IIHR-835, VI046103 x IIHR-834 showed moderately resistant reaction. The root biochemical compounds analysis indicated that, total phenolic content (67.05 mg/g) and flavonoids (121.32 mg/g) were found higher in the inoculated roots of resistant line i.e. IIHR-824 indicating their role in conferring resistance. The identified F1 hybrids having resistance can be explored for commercial cultivation.

The Influence of Cultivation, Storage and Processing Technology on the Nitrate Content in Potato Tubers and Vegetable Crops as the Example of Ecologically and Hygienically Oriented Organic Agricultural Nature Management

The article presents the results of studies of the influence of organic and mineral fertilizers, as well as storage and processing technologies on the level of nitrates in potatoes, carrots and cabbage. The study demonstrated that in order to obtain the high yield of environmentally friendly vegetable crops, it is necessary to use biohumus at a norm of 8 t/ha or the combination of 6 t/ha biohumus and N35P35K40. This treatment can provide the potato yield of 420-440 c/ha, carrots 223-240 c/ha, cabbage 500-520 c/ha, while not exceeding the maximum allowable concentration (MAC) of nitrates. At a same time, studies have revealed that storage and processing of these vegetables under the required standard conditions can significantly reduce the amount of nitrates contained in the products. The work we have done shows an example of organic farming as the ecological and climatic project for carbon sequestration in soils, bioimprovement and bioprotection of soils, for increasing the yield and hygienic quality of the harvest. When processing the resulting vegetable products, toxic hazards to public health are eliminated and the ecological safety of the environment is ensured. Additional measures are needed to control the application of fertilizers to soils, the quality of agricultural products during collection, storage and processing.

Enhancing Okra Growth and Yield Through Foliar Nutrient Application in Conjunction with Mulching and Drip Irrigation

Background: Okra (Abelmoschus esculentus) is an important vegetable crop that belongs to family malvaceae and is grown both in tropical and subtropical regions of India. In north-coastal Andhra Pradesh, okra is cultivated frequently so, optimizing the nutrient management practice is an efficient method for increasing yield. Among those practices, foliar fertilizers, mulching and irrigation methods are essential in maximizing the yield and quality of okra. Therefore, the present investigation deals with the combined effects of foliar nutrients, mulching and irrigation methods, providing valuable data for sustainable okra production in a particular area. Methods: The present investigation was conducted during June to September 2023, with seven different treatments using randomized block design. This experiment mainly focuses on combinations of mulching and foliar sprays of 19:19:19 and 13:0:45 at different concentrations. Collected data were analyzed using ANOVA and fisher’s least significant difference test at a 5% significance level. Result: Among all the treatments, 100% RDF along with the foliar application of 19:19:19 @ 1.0% + 13:0:45 @ 2% at 30, 45 and 60 days after sowing has proven the best treatment, where it recorded the highest yield of 101 q per hectare (Q/ha) due to the application of sufficient nutrients. Whereas, the lowest yield was recorded with control plot due to insufficient nutrient supply in relation to growth and yield parameters.

Impact of Levels of Nutrient Management on Economics of Soybean-onion and Soybean-potato Cropping System

Background: Nutrient management and cropping sequence are two important factors which affect productivity and profitability of crop. Profitability is one the important part of the successful crop production. Soybean fixes atmospheric nitrogen in soil and partially fulfills the nitrogen requirement of succeeding crops. There is a need for a suitable substitute crop or cropping systems after soybean to improve the soil fertility and productivity to maximize the profitability. The plains of Maharashtra are well suited for onion and potato cultivation. There is scope for increasing the area, production and productivity of onion and potato crop. Majority of farmers in Maharashtra following soybean-wheat and soybean-chickpea crop sequence while in present investigation soybean is grown in sequence with vegetable crop such as onion and potato which could help to increase profitability through higher net return and B: C ratio. Methods: The experiment was laid out in split plot design with three replications. Six combinations of two crop sequences (soybean-onion and soybean-potato) and three levels of nutrient management viz., 50% RDF+FYM 5 t ha-1+ biofertilizer (N1), 75 % RDF+ FYM 5 t ha-1+ biofertilizer (N2) and 100 % RDF+ FYM 5 t ha-1+ biofertilizer (N3) were the main plot treatments in kharif season replicated three times in randomized block design. During rabi season each main plot treatment of nutrient management level was split into three sub plot treatments with three levels of recommended dose of fertilizer viz., 75% RDF (F1), 100% RDF (F2) and 125% RDF (F3) to rabi season crops resulting in eighteen treatment combinations replicated three times in split plot design. The data pertaining to growth characteristics, yield characteristics, economics of soybean (kharif) and onion or potato (rabi) was collected at regular interval in 2017-18, 2018-19 and 2019-20 at Agronomy Farm, Dr. PDKV, Akola which was analyzed statistically in SPD (split plot design). Result: Soybean-onion crop sequence registered higher profitability in terms of GMR, NMR and B: C in comparison with soybean - potato crop sequence. Soybean crop supplied with 100% RDN+ 5 t FYM ha-1 + Biofertilizer (Rhizobium japonicum+ PSB+ Tricoderma viridi) recorded highest GMR, NMR and B:C ratio over lower levels of treatments in all year experimentation. Rabi crops treated with 125% RDF recorded GMR, NMR and B:C ratio over lower levels of treatments in all years of experimentation.

Green guardians: Harnessing biopesticides for sustainable vegetable pest management

Insect pests pose significant challenges to vegetable crops, causing not only economic losses but also compromising the quality of our food. Shockingly, up to 20 % of globally produced goods fall victim to these insidious invaders. While chemical insecticides have historically bolstered food production, they come with notable drawbacks, including handling risks, residue concerns and negative impacts on non-target species and the environment.Though they have not yet completely replaced chemical insecticides, biopesticides are becoming key in reducing pesticide overuse and promoting safer, residue-free food and environments. Derived from plants and microorganisms, biopesticides offer a safer alternative, ranging from plant extracts to microbial agents such as bacteria, fungi, viruses and nematodes. Additionally, insect hormones and semiochemicals, along with silica-based mineral products like activated clay and rice husk, contribute to eco-friendly pest control solutions. Cutting-edge nano biopesticides also deliver unparalleled pest control with precision targeting and excellent environmental credentials.In this comprehensive exploration, we delve deep into the myriad forms of biopesticides, their commercial availability, modes of action and the advantages and disadvantages in vegetable pest management. Crucially, we illuminate the path toward integrating biopesticides into holistic pest management strategies, which can lead to healthier crops, increased yields and more sustainable agricultural practices. By emphasizing biopesticides, we can promote environmental safety and support a greener future in agriculture.

Harnessing Biocontrol Potential of Streptomyces rochei Against Pythium aphanidermatum: Efficacy and Mechanisms.

Tomato (Solanum lycopersicum) and chilli (Capsicum annuum) are globally significant vegetable crops susceptible to damping-off disease caused by Pythium aphanidermatum, leading to substantial yield losses. The study aimed to document the biocontrol and plant growth promotion potential of Streptomyces rochei against damping-off disease in tomato and chilli. The actinobacterial isolates ACS18 followed by ACT30, and AOE12 were accomplished as the most effective antagonists against P. aphanidermatum in vitro. Molecular characterization confirmed these isolates as members of Streptomyces genus, with ASH 18 the top performer identified as S. rochei isolate. Analysis of biomolecule through GC-MS during ditrophic interaction between pathogen and S. rochei showed the presence of various antifungal metabolites which were directly related to suppression of the pathogen. Subsequently, S. rochei was formulated into a talc-based preparation and used as seed treatment and soil application against damping-off. In greenhouse trials, significant reductions in damping-off incidence were observed, Furthermore, seedlings treated with S. rochei displayed enhanced root and shoot lengths compared to the uninoculated controls. These benefits potentiate S. rochei as a promising biocontrol agent and demonstrating its dual benefits of disease suppression and promotion of seedling growth.

PP 1/334 (1) Evaluation of mating disruption techniques against Lepidopteran pests in vegetable and ornamental crops under protected conditions

<scp>PP</scp> 1/334 (1) Evaluation of mating disruption techniques against <i>Lepidopteran</i> pests in vegetable and ornamental crops under protected conditions

Cu Concentration in Vegetable-Cultivated Soil: Comparison Between Open Fields and Protected Environments in Brazil

High copper (Cu) concentration in soils used for vegetable production is an agricultural, social and environmental issue. The excess of Cu in soil can cause toxicity in plants, reducing growth and yields. Moreover, Cu can also be absorbed and accumulated in edible organs, increasing risks for human health. This study aimed to compare Cu fractions in soils: (1) non-cultivated, natural soil (NC), (2) soils cultivated with open field crops (FCs) and (3) soils cultivated in controlled environments (CEs). The survey was carried out on 25 sites in Rio Grande do Sul (Southern Brazil), with each site containing the three types of soils described above. From these sites, the four with the highest soil Cu concentrations were selected to compare soluble (Cu-CaCl2), available (Cu-EDTA) and total (Cu-EPA) Cu. Both total and available soil Cu concentration in soil solution, in CE and FC areas were higher than in NC. At sites 23R1 (Oxisol) and 11R1 (Molisol) the soluble and available Cu content was higher in the FC environment than in CEs, and the same was observed for the total Cu content at sites 23R1 (Oxisol) and 9R1 (Molisol). Some FC soils showed total Cu concentrations higher than the limits established by Brazilian environmental legislation, being, as a consequence, potentially contaminated. Soil monitoring and cropping practices must be adopted to reduce the Cu content in soils of vegetable crops in this region.

Fusarium oxysporum f. sp. apii Race 4 Threatening Celery Production in South Florida.

Fusarium wilt, caused by Fusarium oxysporum f. sp. apii (Foa), is a vascular disease affecting celery. This soilborne pathogen is classified into four distinct pathogenic races: 1, 2, 3, and 4. Notably, race 4 emerges as the most virulent, representing the latest evolutionary development of this pathogen, which was first reported in 2013 in California. In 2022, celery plants in South Florida exhibited typical Fusarium wilt symptoms, with the disease reaching a 100% incidence and causing yield losses ranging from 20 to 100%. Given the significance of celery as a vegetable crop and the severity of this outbreak, the primary objective of this study was to identify and characterize the causal agent of Fusarium wilt in South Florida. The second goal aimed to test the pathogenicity and virulence of the Fusarium isolates from Florida on celery and parsley plants. Using race-specific primers and dual-loci phylogenetic analyses, the isolates surveyed in this study were identified as Foa race 4. Pathogenicity assays in the greenhouse showed that the Foa race 4 isolate from celery induced disease not only on the two celery cultivars (Duda 30 and Duda 71) but also on two commonly cultivated parsley varieties (curly and Italian). Our study also revealed that the Foa race 4 significantly (P < 0.05) affected plant health attributes in all cultivars, including plant height, total plant weight, and root weight. Interestingly, the pathogen exhibited higher (P < 0.0001) virulence on parsley than celery based on vascular discoloration. These findings strongly indicate the urgency of comprehending and managing Fusarium wilt on celery and related crops. Furthermore, the ability of Foa race 4 to affect different plant species highlights a potential threat to agricultural production, emphasizing the need for proactive measures to mitigate the impact of this virulent pathogen.

Chloroplast genome characteristic, comparative and phylogenetic analyses in Capsicum (Solanaceae)

BackgroundCapsicum (Solanaceae) is a globally important vegetable crop and is also used therapeutically in traditional medicine systems. However, little is known of the genetic variation within the commonly grown cultivars, the evolutionary relationships and differences in the chloroplast (cp.) genomes between Capsicum species remain unclear.ResultsThe cp. genomes of 32 Capsicum varieties in three species from 6 countries were investigated. The cp. genome of Capsicum was found to be ~ 156 kb in length and to contain 113 unique genes, of which 79 encoded proteins, 30 encoded transfer tRNAs, and 4 were for ribosomal RNAs. The 32 varieties that we chose for study represented 13 genotypes, containing a total of 608 indels, 83 SNPs, 47 SSRs and 281–306 repeat sequences. We then included several previously sequenced Capsicum cp. genomes, and found that the nine investigated species showed a number of differences in the characteristics of the four IR boundaries, and it was the non-coding regions that contained the most variable regions. We conducted a phylogenetic reconstruction using the cp. genomes of 43 representative species of Solanaceae, and the resulting phylogeny generally reflected the currently accepted classification, with the species of the pungent group having close relationship with one another.ConclusionsThis study provides a comprehensive analysis of Capsicum chloroplast genomes, revealing significant variations in IR boundaries and other genomic features. These findings enhance our understanding of Capsicum evolution and genetic diversity.

Evaluation of F2 Segregating Population of Chilli (Capsicum annuum L.) for Yield and Leaf Curl Virus Resistance

Chilli (Capsicum annuum L.) is an important vegetable crop, cultivated worldwide for its fruits which are valued for pungency, flavor, and nutritional benefits. However, chilli production is significantly restricted by various biotic stresses, especially the Chilli leaf curl virus (CLCV). The present study was conducted at the Department of Vegetable Science, College of Agriculture, Vellayani, Kerala Agricultural University during 2020-2021 to evaluate the F2 segregating population of chilli crosses viz., CHIVAR-6 x Sel-4 and CHIVAR-10 x Sel-3 for yield and leaf curl virus resistance. Evaluation of vegetative and yield related traits was conducted on these populations under the field conditions. Significant variability was observed for various traits such as plant height, fruits per plant, fruit length, yield per plant and resistance to leaf curl virus. The scoring for chilli leaf curl virus was done and based on the scoring the segregants were categorized into highly resistant, resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible. Among the F2 population of the first cross, fruits per plant, plant height, fruit weight and fruit girth showed high and positive correlation with yield per plant. The segregants of the second cross recorded significant positive correlation for fruits per plant, plant height and fruit length with yield. The results of the study provide valuable insights into breeding for both high yield and leaf curl virus resistance, crucial for enhancing chilli production under the challenging situations.

A Comprehensive Review of Nano-sized Silica’s Effects on Plant Growth, Molecular Responses, and Biochemical Changes

Silicon (Si) is a tetravalent metalloid and second most abundant on earth approximately 28%. Slags were used in agriculture as a silica fertilizer (10–28% Si); which improvise degraded crop soils, as well as crop growth and disease resistance. Si improves abiotic stress in crop lodging, UV tolerance, improves water uptakes and blocking the NaCl toxicity was observed in Gramineae family. It showed tolerance to biotic stress in terms of physical strengthening of plants against microbial infestation and activation of defensive enzymes such as peroxidase, polyphenol oxidase, lipoxygenase, phenylalanine ammonia lyase. There was an enhanced vegetative growth and germination percentage in varied vegetable crops with 100 to 500ppm range of silica nanoparticles. The plants available Si (H4SiO4) form in soil solution ranges about 0.1 to 0.6 mM and it get absorbed from roots via xylem to shoot containing a specialized cell surface protein called as Nod26-like major intrinsic protein (NIP) of aquaporin family. The list of total genes responsible for uptake of silica form are Low silica genes (Lsi1, Lsi2, Lsi3, Lsi6) and Si efflux transporter genes (SIET3, SIET4, SIET5). The nano-sized silica have been proven to be more validated impact on genes responsiveness via morpho-physiological parameter relationship. It is concluding that, use of silica in commercial crops have deep root to influence the genes and a bright future in its crop growth development aspects.

SlVQ15 recruits SlWRKY30IIc to link with jasmonate pathway in regulating tomato defence against root-knot nematodes.

Tomato is one of the most economically important vegetable crops in the world and has been seriously affected by the devastating agricultural pest root-knot nematodes (RKNs). Current understanding of tomato resistance to RKNs is quite limited. VQ motif-containing family proteins are plant-specific regulators; however, whether and how tomato VQs regulate resistance to RKNs is unknown. Here, we found that SlVQ15 recruited SlWRKY30IIc to coordinately control tomato defence against the RKN Meloidogyne incognita without affecting plant growth and productivity. The jasmonate (JA)-ZIM domain (JAZ) repressors of the phytohormone JAs signalling associated and interfered with the interaction of SlVQ15 and SlWRKY30IIc. In turn, SlWRKY30IIc bound to SlJAZs promoters and cooperated with SlVQ15 to repress their expression, whereas this inhibitory effect was antagonized by SlJAZ5, forming a feedback regulatory mechanism. Moreover, SlWRKY30IIc expression was directly regulated by SlMYC2, a SlJAZ-interacting negative regulator of resistance to RKNs. In conclusion, our findings revealed that a regulatory circuit of SlVQ15-SlWRKY30IIc and the JA pathway fine-tunes tomato defence against the RKN M. incognita, and provided candidate genes and clues with great potential for crop improvement.

Integrative multi-omics analysis of chilling stress in pumpkin (Cucurbita moschata).

Pumpkin (Cucurbita moschata) is an important vegetable crop that often suffers from low-temperature stress during growth. However, the molecular mechanism involved in its response to chilling stress remains unknown. In this study, we comprehensively investigated the effect of chilling stress in pumpkin seedlings by conducting physiological, transcriptomic, and metabolomic analyses. Under chilling stress, there was an overall increase in relative electrical conductivity, along with malondialdehyde, soluble sugar, and soluble protein contents, but decreased superoxide dismutase and peroxidase activities and chlorophyll contents in seedling leaves compared with controls. Overall, 5,780 differentially expressed genes (DEGs) and 178 differentially expressed metabolites (DEMs) were identified under chilling stress. Most DEGs were involved in plant hormone signal transduction and the phenylpropanoid biosynthesis pathway, and ERF, bHLH, WRKY, MYB, and HSF transcription factors were induced. Metabolomic analysis revealed that the contents of salicylic acid (SA), phenylalanine, and tyrosine increased in response to chilling stress. The findings indicated that the SA signaling and phenylpropanoid biosynthesis pathways are key to regulating the responses to chilling stress in pumpkins. Overall, our study provides valuable insights into the comprehensive response of C. moschata to chilling stress, enriching the theoretical basis of this mechanism and facilitating the development of molecular breeding strategies for pumpkin tolerance to chilling stress.

Population fluctuation of the whitefly Bemisia tabaci Gennadius, 1889 (Homoptera - Aleyrodidae) on vegetable crops and effect of two entomopathogenic fungi Verticillium sp. and Paecilomyces sp.

The cotton or sweet potato whitefly, Bemisia tabaci, is a major pest in Algeria, affecting various greenhouse-grown crops. This study aimed to monitor B. tabaci population dynamics on tomatoes, peppers, zucchinis, and strawberries to understand its infestation patterns. The methodology involved regular monitoring of pest activity on these crops and a laboratory bioassay to assess the efficacy of two entomopathogenic fungi, Verticillium sp. and Paecilomyces sp., in controlling the whitefly. Results revealed that B. tabaci was most prevalent on tomatoes, with a 43.73% infestation rate, followed by peppers at 24%, zucchinis at 19.14%, and strawberries at 13.11%. In addition, laboratory trials were conducted to evaluate the efficacy of two entomopathogenic fungi, Verticillium sp. and Paecilomyces sp., in controlling the whitefly. Verticillium sp. showed higher efficacy, achieving a 73% mortality rate, while Paecilomyces sp. resulted in a significantly lower mortality of 23%. These findings suggest that Verticillium sp. holds promise as a biological control agent for managing B. tabaci in Algeria, particularly on tomato crops.

Evaluating the Efficacy of Insecticide on the Management of Onion Thrips (Thrips tabaci, Lindemann) in Northwestern Zone of Tigray

Ethiopia has enormous potential to produce the onions throughout the year both for domestic use and export market. It is also the most cultivated and high market value of vegetable crops in Tigray Northern Ethiopia. However, the productivity of onion is highly constrained such as insect pests, diseases, lack of improved verities, lack of improved management practices etc. The major insect pest of onion is Onion thrips and important pests especially in areas where onions are grown under irrigation. The purpose of this study was to test the insecticide chemicals application and application frequency on the Onion production technologies. Therefore, field experiment was conducted to evaluate the insecticide chemical applications with frequency application in 2017 and 2018 under irrigation conditions. Thirteen treatments were used three different insecticide types namely Karatae 5% EC, Dimethote 40%EC, Profit72%EC with four different spraying frequency and untreated (control) laid out in Randomized Complete Block Design (RCBD) with three replications. The current findings showed that the profitable yield was obtained Karatae 5% EC (1st spray) (14.25 t ha-1) followed by Profit72%EC (4th spray) that is (20.25 t ha-1) and the obtained profit was 128053 &amp;181788 birr per ha with the maximum Marginal Rate of Return of 3025 &amp; 2417% respectively in Tselemti woreda. In Medebaayzana woreda also, the profitable yield was obtained Karatae 5% EC (1st spray) (25.79 t ha-1) followed by Karatae 5% EC (4st spray) at (27.75 t ha-1) &amp; Dimethote 40% EC (3rd spray) at (25.78 t ha-1) and 231976, 249463 &amp; 231544 birr per ha obtained profit with the maximum Marginal Rate of Return of 2634, 2395 &amp; 2311 % respectively. Therefore, Karatae 5% EC (1st spray) in Tselemti &amp; Medebayzana woreda &amp; Profit72%EC (4th spray) in Tselemti woreda and Dimethote 40% EC (3rd spray) in Medebayzana woreda was profitable preventive Onion Thrips for Onion production in the studies area.

Polyamines: pleiotropic molecules regulating plant development and enhancing crop yield and quality.

Polyamines (PAs) are pleiotropic bioorganic molecules. Cellular PA contents are determined by a balance between PA synthesis and degradation. PAs have been extensively demonstrated to play vital roles in the modulation of plant developmental processes and adaptation to various environmental stresses. In this review, the latest advances on the diverse roles of PAs in a range of developmental processes, such as morphogenesis, organogenesis, growth and development, and fruit ripening, are summarized and discussed. Besides, the crosstalk between PAs and phytohormones or other signalling molecules, including H2O2 and NO, involved in these processes is dwelled on. In addition, the attempts made to improve the yield and quality of grain and vegetable crops through altering the PA catabolism are enumerated. Finally, several other vital questions that remain unanswered are proposed and discussed. These include the mechanisms underlying the cooperative regulation of developmental processes by PAs and their interplaying partners like phytohormones, H2O2 and NO; PA transport for maintaining homeostasis; and utilization of PA anabolism/catabolism for generating high-yield and good-quality crops. This review aims to gain new insights into the pleiotropic role of PAs in the modulation of plant growth and development, which provides an alternative approach for manipulating and engineering valuable crop varieties that can be used in the future.