Horizon e-Publishing Group (HePG): E-Journals
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Forecasting tomato\u27s foe: Predicting groundnut bud necrosis disease using extended range weather dynamics
Get PDFTomato (Solanum lycopersicum L.), a staple vegetable crop in the Solanaceae family, suffers significant yield losses due to the groundnut bud necrosis virus (GBNV). This thrips-transmitted virus can cause up to 100% yield reductiondepending on the stage of infection. A study conducted in Coimbatore, Tamil Nadu, India during the summer of 2023 and 2024, investigated the epidemiology of GBNV. Using weather correlation analysis and principal component analysis (PCA), key weather factors influencing the spread of thrips and GBNV were identified. In 2023, the thrips population peaked in mid-April, followed by GBNV incidence in early May. In 2024, thrips peaked in early May, with GBNV incidence reaching its highest levels in the third week of May. This demonstrated a direct correlation between thrips population dynamics and GBNV progression, although variations in timing with observed between the two years. The analysis highlighted temperature and relative humidity (RH) as consistent, critical weather parameters influencing thrips populations and GBNV incidence, particularly with two-week time lags. By correlating weather conditions with thrips and GBNV incidence across various time lags, this study contributes to the development of anextended-range weather forecast-based GBNV forewarning system. Such a system enhances preparedness and response strategies, mitigating the impact of GBNV on tomato crops and promoting food security. This multidisciplinary approach supports sustainable farming practices in the face of climate uncertainties while bolstering agricultural resilience
Unveiling a symptomatic disease in custard apples: effective management strategies against fruit degradation
Get PDFAnnona squamosa is a tropical fruit susceptible to various diseases that significantly impact its yield and quality of the fruits. Colletotrichum spp. rank among the top ten most destructive fungal pathogens globally, occupying the 8th position due to their significant impact on agriculture. These fungi are hemibiotrophic in nature, with over 1,000 known species, and most crops are susceptible to at least one of these. They cause various diseases, including leaf spots, blights, and fruit rots. Symptoms manifest on horticultural crops\u27 leaves, flowers, fruits, and branches, often resulting in substantial yield losses. Colletotrichum species exhibit a latency mechanism that can exacerbate damage during post-harvest storage, leading to up to 80 % production losses in some instances. Experiments were carried out in Randomized Block Design with seven treatments and three replications at the C1 block of Regional Research Station, TNAU, Aruppukottai, Virudhunagar District, Tamil Nadu, to identify and manage the pathogens causing leaf spot and fruit rot in custard apples. Pathogens isolated from the rotten fruit rind and mesocarp were identified as Colletotrichum siamense (Acc No: OM736073) and Colletotrichum gloeosporioides (Acc No: OM736066), respectively, through morphological and molecular analyses. The isolated DNA of the respective pathogens were amplified using PCR with ITS 1 & 4 primers. Then, the amplified product (550bp) was sequenced and submitted to the NCBI website. Pathogenicity tests confirmed these isolates as the causative agents for the leaf spot and fruit rot symptoms. Field experiments were conducted for two consecutive years to evaluate the efficacy of various treatments in managing leaf spot and fruit rot diseases. Before spraying, the leaf spot and fruit rot incidence are 77 and 27, respectively, in the control plot. The combined fungicide formulation, Tebuconazole 25 % + Trifloxystrobin 50 % WG (0.1 %), showed the highest disease reduction (60.44 %) and yield enhancement (15.50 kg/tree). The spraying of neem seed kernel extract (5 %) and Bacillus subtilis (0.5 %) also resulted in significant disease reduction and yield improvement. The study highlights the importance of combining chemical and biocontrol agents with integrated disease management strategies to manage custard apple diseases effectively. Neem products are always safe for the environment, Humans and animals and when they are used in correct concentration they won\u27t leave any residues. Likewise, biocontrol agents are target-specific and never harm the beneficial microbes in soil and the plant system
Optimization of gamma irradiation doses (60Co) for mutagenesis in strawberry (Fragaria × annanasa Duch) cv. Winter Dawn
No full textStrawberry, a vegetatively propagated crop, exhibits limited genetic variation, which constrains its adaptability and improvement potential. Gamma-ray radiation is a promising approach for enhancing genetic diversity and improving strawberries. Strawberry runners of the Winter Dawn cultivar were irradiated using 60Co, with doses ranging from 20 Gy to 40 Gy administered at a consistent rate of 1.52 Gy per minute to evaluate mutagenic effects. The survival effects in gamma irradiation-treated runners were recorded at 30 days after transplantation. An LD50 analysis was conducted to assess physiological impacts, and the lethal dose value was found to be 40 Gy, resulting in 50% mortality. Distinct differences in survival rates were observed between treated and untreated runners, with the highest survival rate (88%) at 20 Gy. The 30 Gy dose-treated runners exhibited the highest growth parameters, including crown diameter (14.32 mm), primary root length (29.50 cm), secondary root length (5.5 cm), and number of roots (39.6). Among fruit quality traits, maximum fruit length (39.84 mm), and fruit diameter (27.80 mm) were observed in runners treated with a 30 Gy gamma irradiation dose. Significant variations in survival, growth, and fruit quality were observed across different gamma irradiation doses. These findings provide a foundation for future efforts to develop potential strawberry mutants with improved traits through gamma irradiation. These findings provide a foundation for future efforts to develop potential strawberry mutants with improved traits through gamma irradiation
Synergistic effects of seaweed extract presoaking and foliar spray on the performance of paddy improved kavuni (CO 57)
Get PDFRice (Oryza sativa L.) is a staple food crop and a primary source of sustenance for more than half of the world\u27s population. Seed treatments and foliar applications have emerged as effective methods to enhance growth and yield attributes. In this study, improved kavuni (CO 57) seeds were used for a field experiment conducted during the Samba season (2023). The experiment was designed using a Factorial Randomized Block Design with 15 treatments and three replications, focusing on foliar spray applications. The primary objective was to evaluate the impact of Sargassum myricocystum, Kappaphycus alvarezii methanol extract and foliar spray on rice growth and productivity. The results revealed that the combined application of presoaking seeds in 0.5 % Sargassum myricocystum methanol extract with a foliar spray of 2.5 % seaweed extract at the panicle initiation and flowering stages (T1F2) significantly enhanced plant growth and yield parameters. Higher plant height (121 cm), leaf area index (4.85), dry matter production (5180 kg ha- ¹), productive tillers (281 m- ²), filled seeds per panicle (170), 1000 seed weight (22.34 g), seed yield (4552 kg ha- ¹) and straw yield (6370 kg ha- ¹) were recorded under T1F2 compared to other treatments. The use of organic input seaweed extracts, improved plant quality and yield sustainably without harming the natural ecosystem. This study highlights the significant potential of seaweed extracts in enhancing overall crop performance, leading to optimal plant growth characteristics and yield attributes. The findings emphasise the role of organic inputs in promoting sustainable agriculture, contributing to environmental conservation while supporting food security
Reducing the incidence of Fall Army Worm (FAW) in irrigated maize (Zea mays L.) through intercropping systems
Get PDFPest management strategies involving intercropping systems are being developed in different research stations. However, findings on location specific management are very limited. In order to address these problems and enhance maize productivity by identifying location specific strategies, field experiments were conducted at the Department of Millets, Tamil Nadu Agricultural University, Coimbatore during kharif, 2020 and rabi, 2020-21 to reduce the incidence of FAW in irrigated maize through different intercropping systems in sandy clay loam soil. The experiments consisted of 5 treatments viz., T1- Maize + Tephrosia, T2- Maize + Fenugreek, T3- Maize + Coriander, T4- Maize + Marigold and T5- Maize alone and these were laid out in a Randomized Complete Block Design (RCBD) with 3 replications. On the border of experimental field, a row of Bajra Napier Hybrid grass was planted to study the influence on FAW. The results of experiments revealed that the T4- Maize + Marigold treatment was superior in reducing the incidence of FAW in irrigated maize among the different intercropping systems owing to the occurrence of natural enemies and repelling nature of marigold which recorded higher maize equivalent yield of 6089 kg ha-1 with a B:C ratio of 1.84. This system of intercropping should be adopted by the farming community to reduce the incidence of FAW in maize as it is an eco friendly approach, which sustains the productivity of maize
South Western Ghats of India: A niche of clove (Syzygium aromaticum (L.) Merr. & Perry) diversity
Get PDFThe survey conducted across major clove (Syzygium aromaticum (L.) Merr. & Perry) growing regions of the South Western Ghats of India, especially in the states of Kerala and Tamil Nadu, identified thirty accessions with distinct characteristics and superior yield. Clove accessions were characterized based on twenty-one qualitative and twelve quantitative traits. Significant variations were observed among fifteen qualitative characters with predominant traits including elliptical canopy shape, semi-erect branching pattern, leaf lamina and its apex, mid-bud forming season, clustering pattern of flower, bud size, fruit, and seed shape. The dendrogram constructed using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) grouped thirty accessions into five major clusters at a genetic similarity of 73%, with Accession 19 identified as unique. Principal component analysis of twelve quantitative characters revealed three component groups, explaining 70.85% of the total variance. The score plot generated from the principal component loading grouped the accessions into eighteen clusters. A minimal dataset comprising four characters, namely plant height, canopy spread in East-West direction, number of inflorescences per square meter, and mature bud length, was generated. Observations on both qualitative traits and the minimum data set facilitated the identification of ideotypes. The geographical location was not found to influence genetic diversity significantly
Evaluation of in vitro anti-inflammatory and antioxidant activities of Simarouba glauca leaf extract
Get PDFSimarouba glauca is a medicinal plant native to India and other tropical regions of South and Central America. Although this plant is widely used to cure many diseases, a systematic study is lacking to understand its medicinal value. Thus, we focused on analysing the phytochemical composition of S. glauca leaf extracts and evaluating in vitro anti-inflammatory and antioxidant activities using standard bioassays. The anti-inflammatory activity was conducted using protein denaturation assay, heat-induced hemolysis and lipoxygenase inhibitory assays, which revealed IC50 values of 328 µg/mL, 342.6 µg/mL and 432.1 µg/mL, for the aqueous, ethanol and ethyl acetate extracts, respectively. For antioxidant activity, the aqueous, ethanol and ethyl acetate extracts demonstrated scavenging activity against DPPH and ABTS radicals, with IC50 values of 180.7 ?g/mL, 209.7 ?g/mL and 678.2 ?g/mL for DPPH and 75.3 µg/mL, 83.9 µg/mL and 225.8 ?g/mL for ABTS, respectively. Further, the FRAP assay showed scavenging activity of 72.28±0.76 ?g/28 mL, 72.5±0.75?g/mL and 16.8±0.58 µg/mL and the phosphomolybdate method exhibited significant antioxidant activity of 80.0 ± 0.87 µg/mL, 81.39 ± 0.69 µg/mL and 47.17 ± 0.58 µg/mL, respectively. All these results indicate that aqueous and ethanol extracts of S. glauca leaf display potent anti-inflammatory and antioxidant activities and thus could further be explored for its utility as a therapeutic agent
Effect of gamma rays induced mutagenesis on the agronomical and biochemical traits of acid lime
Get PDFOne of the indigenous citrus crops of India is acid lime, which has a high economic value and unique flavour compared to other citrus fruits. The current study was intended to ascertain the gamma ray dosage that proves lethal for the acid lime variety PKM1. The acid lime seeds were exposed to nine distinct gamma radiation dosages ranging from 5 to 45 Gy with an interval of 5 Gy and compared to untreated control. Different irradiation doses demonstrated substantial differences in morphological and biochemical traits. Increased dosage of gamma radiation leads to significant changes in various agronomic parameters of plant germination, number of plants, plant height, and change in biochemical traits. Various gamma radiation doses revealed a low survival rate after 35 Gy, with LD 50 at 27.86 Gy
Assessment of combining ability and heterosis in bottle gourd (Lagenaria siceraria L.) for yield and attributes character through line × tester design
Get PDFGeneral and specific combining ability variance and their effects were studied for thirteen characters in line × tester mating design in bottle gourd. Based on overall per se performance and among the parents, Narendra Dharidar, Punjab Long, and parents Narendra Rashmi were identified as good specific combiners for a maximum of 5 to 6 attributes, including yield for other contributing traits, suggesting that these parents may be used in the hybridization program aimed at the development of superior genotypes/varieties in bottle guard. Tester Arka Bahar and Narendra Madhuri were considered to be good general combiners for 6 to 8 characters. These parents must be utilized in a suitable breeding programme visa-vis selection breeding for improvement productivity of yield and per unit area in bottle gourd. Based on overall results and per se performance, the F1 hybrids, i.e. Pusa Sandesh × Kashi Ganga, IC-321747 × Narendra Madhuri, and NDBG-132 × Narendra Madhuri emerged to be the good specific combiners for maximum traits, including yield, which may be utilized for obtaining transgressive segregants in the next generation. Out of sixty-four cross combinations, only seventeen hybrids revealed superiority over better parents for yield. The seventeen cross combinations that showed more than 24% heterobeltiosis over better parents include: IC-498541×Narendra Madhuri, IC-592210×Arka bahar, Pusa Sandesh×Narendra Madhuri, NDBG-132×Pusa Naveen, Narendra Rashmi×Kashi Ganga, IC-321412×Pusa Naveen, Narendra Rashmi×Arka bahar, Narendra Rashmi×Pusa Naveen, Narendra Dharidar×Narendra Madhuri, Pusa Sandesh×Kashi Ganga, NDBG-132×Arka bahar, NDBG-132×Narendra Madhuri, Punjab long×Narendra Madhuri, Narendra Jyothi×Narendra Madhuri, IC-592210×Arka bahar, IC-338119×Arka bahar and IC- 498541×Kashi Ganga. This suggests that there is a great possibility to produce higher yielding varieties/genotypes
Elucidation of genetic diversity in distinct brinjal genotypes: Multivariate analysis using D2
Get PDFGenetic divergence study among 45 brinjal genotypes was performed using Mahalanobsis D2 statistics to find prospective genotypes for use in a breeding programme. The genotypes were assessed for 11 traits and divided into twelve clusters based on Tocher’s method. Cluster I had the most genotypes (18), followed by cluster III (5), cluster V (4), cluster IV, VI and IX (3 each), cluster II, VII and X (2 each) and cluster VIII, XI and XII (1 each). The intracluster distances ranged between 0 and 1064.87. Cluster X has the largest intra-cluster distance (1064.87), followed by Cluster IV (831.08). Cluster VIII, XI, and XII had the smallest intra-cluster distance (0). The inter-cluster distances varied from 804.88 to 4758.26. The largest inter-cluster distance was between IX and XI (4758.26), followed by III and XII (3923.90), and the shortest distance was between cluster II and III (804.88). Genotypes from the cluster with a large inter-cluster distance could be selected as parents to produce superior F1 hybrids and segregants. The three characters, fruit length (29.70%), number of primary branches (18.89%), and plant height (14.55%), altogether account for 63.14% of overall divergence. As a result, the combination of those traits could be exploited to develop superior varieties with higher yields