Disease-free Seeds Research Articles

DAYA MULTIPLIKASI EKSPLAN KENTANG AR 8 PADA BERBAGAI KONSENTRASI BENZIL AMINO PURIN (BAP) DAN EKSTRAK BAWANG MERAH DALAM MEDIA DASAR MURASHIGE DAN SKOOG (MS) SECARA IN VITRO

The technique of propagating potato seeds through tissue culture has long been used to produce quality and disease-free seeds. This study aims to test the effect of the combination of BAP and Shallot Extract on the growth of potato plant explants on MS media (Murshige & Skooge). Research in experimental form uses a completely randomized design (CRD) in a factorial pattern consisting of two factors. As the first factor, the growth hormone BAP consists of 4 levels, namely: 0 ppm, 2 ppm, 3 ppm and 4 ppm. Meanwhile, the second factor is: shallot extract consists of 4 treatment levels, namely: 0%, 0.2%, 0.4% and 0.6%. Thus, there were 16 treatment combinations which were repeated 6 times so that the total experimental units were 96. The ABA treatment with a concentration of 2 ppm/liter gave the best effect on the shoot formation time and root formation time of AR 8 potato plant explants. However, the treatment without ABA had a good effect on Shoot length and root length of explant potato plant varieties AR 8. Shallot extract treatment with a concentration of 20% had the best effect on shoot formation time, root formation time, shoot length and number of leaves. However, the treatment with a concentration of 40% had a better effect on the parameters of the number of shoots and the number of explant segments of the AR 8 variety of potato plants. The interaction of the ABA treatment with a concentration of 2 ppm and the shallot extract with a concentration of 20% had the best effect on the time of emergence of shoots and roots on the AR 8 Potato Explants. However, the interaction without ABA (0ppm) and shallot extract had a better effect on the parameters of shoot length, number of leaves, and number of explant segments in the AR 8 potato variety.

Assessment of genetic uniformity in micro propagated plantlets of turmeric (Curcuma longa L.) through DNA markers

Turmeric is herbaceous plant, characterized by long lance-shaped leaves sprouting from its rhizomatous underground stem. Notably, its rhizomes contain the bioactive compounds curcuminoids, renowned for its medicinal and culinary significance. However, meeting the surging demand for turmeric, particularly during off- seasons, presents a formidable challenge due to the sluggish vegetative propagation rate in Curcuma longa. Given the scarcity of sexual reproduction in turmeric, micropropagation emerges as the convenient method for obtaining disease-free seeds. In addressing the challenge of direct regeneration of the native Erode local cultivar of turmeric, this study endeavors to establish a protocol for in vitro plantlet production. Results indicate that multiple shoots were successfully induced, notably with 13.32 μM of 6-benzylaminopurine (BAP), yielding a response rate of 73.2±4.7% and an average shoot count of 6.95±0.81 per explant. Subsequently, a concentration of 17.76 μM of BAP demonstrated a response rate of 56.5%±4.7%, with an average shoot count of 5.94±0.81 per explant. Additionally, a combination of 13.32 μM BAP and 2.68 μM Naphthaleneacetic acid (NAA) resulted in 8.65±0.47 shoots per explant, with a response rate of 73.66±1.25%. Similarly, 13.32 μM BAP combined with 5.37 μM NAA yielded 7.32±0.47 shoots per explant, with a response rate of 72.33±0.47%. The acclimatization of plantlets in a greenhouse exhibited a remarkable survival rate, ranging from 90% to 98%. Importantly, all regenerated plantlets closely resembled the mother plants morphologically. Genetic uniformity assessment, employing 10 ISSR and 4 DAMD markers, indicated more than 90% uniformity among one mother plant and regenerants. This indicates a significant genetic uniformity, ensuring consistency in desired traits across the regenerated plantlets.

Effect of Intra Row Spacing on Growth, Yield Components and Yield of Garlic (Allium Sativum L) at Fitch, North Showa Zone of Oromia, Ethiopia

Garlic (Allium sativum L.) is a monocotyledonous aromatic plant belonging to the Alliaceae family and genus Allium. It is used as a spice and medicinal plant. The production of garlic in Ethiopia is low as compared to other growing countries. This is due to different factors like the unavailability of appropriate disease-free seeds (Cloves), inappropriate agronomic practices, i.e., sowing time, seed rate, and both intra- and inter-row spacing. That is the reason why the research report was studied. A field experiment was conducted at the Fiche, Salale University, General Tadesse Biru campus demonstration site during the 2020 cropping season. The objective of the study was to identify the effect of intra-row spacing on the growth, yield, and yield components of garlic. One local variety of garlic, which was bought from Fiche Market, was used for the field experiment. The experiment was laid out using a randomized complete block design (RCBD) with three replications and four treatments/intrarow spacing, i.e., 8cm, 10cm, 12 cm, and 14cm between plants. Growth, yield, and yield components data were collected and subjected to analysis of variance (ANOVA) using SAS 9.3, and least significant difference (LSD) at p<0.05 probability was used to separate means. The ANOVA showed significant variation among all collected parameters. The wider the plant spaced, the better the growth performance of the garlic plant. However, the yield-related parameters are good indicators of yield. Thus, treatments, which are bulb weight and number of cloves per bulb, showed better performance of morphological parameters and also suggest a positive relationship with increasing plant spacing statistically. According to those ANOVA results, farmers or growers may produce more yield with a plant spacing of 14*25 because all parameters are significant as compared to other treatments.

Convolution Neural Network Approach for Early Identification of Patchouli Leaf Disease in Indonesia

Indonesia is the largest supplier of patchouli oil in the world market, contributing 80%–90%. Most patchouli oil products are exported in the perfume, cosmetics, pharmaceutical, antiseptic, aromatherapy, and insecticide industries. The emergence of patchouli leaf disease significantly reduced the production of wet, dry, oil, and patchouli alcohol. Therefore, selecting patchouli cuttings (seedlings) that are entirely healthy and disease-free is very important to prevent disease transmission from one area to another. In addition, the selection of disease-free seeds is also essential to prevent the use of diseased patchouli plant propagation. So far, the early identification of patchouli plant health is carried out through visual observations by experts using antiviral serum tested in the laboratory. However, this testing process is expensive. Therefore, in this paper, we proposed a novel Convolutional Neural Network (CNN) architecture for patchouli leaf diseases. We proposed a system for early identification of whether a patchouli leaf is diseased or healthy. Our CNN model uses three convolution layers, a dense layer, and a dropout layer. We compare the proposed model with well-known models, namely EfficientNetB0, AlexNet, InceptionV3, MobileNetV2, and VGG16. The results show that the proposed model outperformed five well-known models as a comparison. It has been confirmed by predicting the new and different testing data. This research contributes to the early identification of patchouli leaf diseases to reduce the expensive costs of identifying patchouli leaf diseases.

Trapping and Repellent Techniques for Huanglongbing Management in Citrus Orchards: Innovative Strategies to Combat Vector-Mediated Disease Transmission

The global increase in human population has heightened the demand for citrus fruits and their derivatives, necessitating effective management strategies to mitigate the impact of huanglongbing (HLB) disease. Caused by gram-negative bacteria such as ‘Candidatus Liberibacter asiaticus’, ‘Candidatus Liberibacter africanus’, and ‘Candidatus Liberibacter americanus’, HLB is primarily transmitted by the insect vector Diaphorina citri. While traditional vector suppression methods using insecticides have proven ineffective, innovative approaches are required to control disease spread. This study aims to address the persistent nature of the vector and its ability to transmit HLB throughout its life cycle by emphasizing trapping and repellent techniques. By implementing early detection methods, utilizing disease-resistant citrus varieties, employing disease-free seeds, enhancing nutritional regimes, and reducing vector populations, promising results have been achieved in reducing vector populations and limiting HLB inoculum. The implications of this research underscore the importance of adopting trapping and repellent strategies, alongside the use of disease-free citrus plants, to effectively manage HLB and safeguard citrus plantations worldwide.

Detection of some registered barley varieties reactions to barley leaf stripe disease

Cereals are a significant agricultural product group with the highest cultivation area and production in Turkey. Among these cereals, barley is an important cereal used in human and animal nutrition, and the most widelycultivated plant after wheat. There are biotic and abiotic factors which affect the yield and quality parameters of barley. Of the biotic factors, barley leaf stripe (agent: Pyrenophora graminea (anamorph: Drechslera graminea) is an important fungal disease. Infections can occur in diseased seeds and in the presence of suitable environmental conditions. Hence, the use of disease-free seeds and resistant cultivars (cvs.) against this pathogen are crucial. With this in mind, this study was carried out with a highly virulent isolate of Pyrenophora graminea, obtained from the Disease and Pest Resistance Unit culture collection in 57 registered barley cultivars in the greenhouses of the Central Research Institute of Field Crops (TARM) in 2021. The experiments were conducted in 3 replications in a randomized block design. Of 57 registered barley cultivars 62%, 15% and 36% of these barley cultivars expressed resistance, moderate resistance, and susceptible reactions, respectively. As a result of the analysis of variance performed on the results obtained, it was concluded that the difference between the mean values of 57 varieties was statistically significant at 1% level (P

Ozone treatment inactivates common bacteria and fungi associated with selected crop seeds and ornamental bulbs

The use of disease-free seeds or bulbs is very crucial to ensure sustainable and profitable agricultural production. Seed-borne pathogens which are responsible for significant yield losses in various crops need to be successfully eliminated with appropriate seed treatments. In this study, we investigated the efficacy of gaseous ozone (O3) and ozonated water treatments on the inactivation of seed-borne fungal and bacterial pathogens of widely cultivated vegetable and cereal seeds, and ornamental bulbs. We demonstrated that O3 application to tomato and cucumber seeds inactivates Fusarium oxysporum f. sp. lycopersici, Fusarium oxysporum f. sp. radicis-lycopersici, Clavibacter michiganensis subsp. michiganensis, Pseuodomonas syringae pv. tomato, and Pseudomonas syringae pv. lachrymans, respectively, with no negative effect on seed germination rate. The sterilization capacity of O3 has substantially increased when the seeds were soaked in water before the treatments. The saprophytic fungal load and the infection rate of Pectobacterium carotovorum subsp. carotovorum on several species and cultivars of ornamental bulbs were suppressed by O3 treatment. A strong decrease in the infection rate of Tilletia caries was also shown in O3-treated wheat seeds under field conditions. Overall, the current study indicated that O3 treatment has great potential in ensuring the use of disease-free seeds or other propagation materials, which is indispensable at the beginning of crop production.

Практика борьбы с заболеванием картофеля (Solanum tuberosum L.) в Азербайджане на примере фитофторы

Potatoes (Solanum tuberosum L.) are the fourth largest crop in the world after rice and corn. In Azerbaijan, the yield of potatoes per unit area is very low compared to other countries of the world. There are many factors that reduce crop productivity, among which diseases such as late blight of potato (Phytophthora infestans) play an important role. Therefore, the fight against this disease is very important. Late blight of potato can be controlled by the following control strategies: use of biological control agents, use of resistant varieties, crossbreeding, use of certified disease-free seeds, use of selective fungicides and agronomic practices such as destruction of cull heaps by freezing or deep burial, destruction sprouting voluntary potato plants in nearby fields during the season, killing infested plants to avoid spreading, shortening periods of leaf wetness and high canopy moisture through proper irrigation times, applying the recommended fungicide spraying program (program must be started before pathogen is detected).

Strategy for Rice Disease Management in Bangladesh

Disease is one of the most limiting biotic factors that affects rice production worldwide. In Bangladesh, there are 10 rice diseases considered as major, which cause economic loss in farmers’ fields. Therefore, the aim of this article is to explore all the feasible avenues of technology deployment on rice disease management to restrict the disease infection at minimum level and thus minimize economic loss. The article is generated using data and/or infromation from published and unpublished works and incorporating authors’ experience. It is evident that periodically (odd year) a disease outbreak or epidemic occurred in Bangladesh such as blast. Under epidemic situation, research findings estimated a yield loss of up to 98% at the highest disease severity level of infection of blast. On the other hand, field survey indicated the highest of 65.4% yield loss from severly infected field with the disease. To overcome the epidemics in odd years and to keep the loss under economic threshold level, it is necessary to undertake preventive measures such as planting of resistant or tolerant varieties, use of disease-free seeds from healthy plants, use of balanced fertilizer where applicable, and following feasible crop rotations. Currently, it is urgent need for developing strong and precise weather-based disease-risk forecasting system at least one week’s lead time based on real-time weather data. Subsequent quick management options such as disease-specific fungicidal treatment should be communicated to all stakeholders using fast-delivery media such as TV channels and SMS could be efficient and effective ways to address the disease outbreak under epidemic situation. To address annualized yield loss, it is suggested to execute interventions like effective training to the root level (both for farmers and extension personnel) and conducting demonstration in farmers fields, regular field monitoring, digitalization in disease management sector, revive indigenous technologies as appropriate, and improving rice production system. To continously improve rice disease management sector, this paper has proposed an innovative action for three decades through to 2050 under the banner ‘Location, Variety and Disease Specific Smart Management’ on research, development and extension. Bangladesh Rice J. 25 (1) : 23-36, 2021

English

The practices of using isolation and distance in the seed production of open pollinated crops are fundamental concepts to ensure seed purity. We uniquely examined the effectiveness of replacing isolation plots for seed production and grass breeding with different sizes of novel nonwoven synthetic fabric pollination control tents (PCTs). Two fabrics, DWB10 and DWB24, were used along with multiple genotypes of tall fescue at Ardmore, Burneyville and Gene Autry locations in Oklahoma, USA during 2018 and 2019. Treatment effects were consistently significant in both years, but location differences were more pronounced in 2019. Interactions of treatments with locations or genotypes were not predominant. The two tent fabrics, generally, performed equally well for various traits in both years. Tent performance for both fabrics was particularly superior over control for various traits in 2019 (e.g., DWB10 tent showed a 36% increase for seed yield (SY) over the control). Introduction of fans in tents for increasing pollen flow in 2019 was not advantageous as it reduced the SY by 23%. The average temperature within tents was higher with lower average humidity than the control producing a microclimate for good yield and disease free seeds. The final germination (%) of seeds from tents and controls at 21 days was high and not much different with a minimum overall germination of 89% at Burneyville in 2018. There was no evidence of pollen contamination from tetraploid ryegrass pollen in any of the tent fabrics. Bad weather in 2018 affected the sturdiness of tents, but modifications in 2019 corrected all such mishaps. Further improvements in the structures, design and cover have since been made for field exploitation of technology in grass improvement and seed multiplication. Key words: Ryegrass, fescue grass, pollination control tents, nonwoven fabrics. &nbsp

Potato cyst nematode: A hidden enemy of potato cultivation in hills

Potato cyst nematode is the most devastating pest and is one of the most important problem in potato production in India as well as worldwide. Recently, govt. of India kept quarantine regulations in Jammu and Kashmir, Himachal Pradesh and Uttarakhand besides Tamil Nadu which shows the seriousness of this problem. In absence of host this nematode can survive in a protective and hard cyst. Under favourable environmental and crop conditions the nematode infects the roots and gets their nourishment for development and reproduction. As a result of this plant shows yellowing and stunted growth which ultimately cause yield reductions. To get rid of this problem integrated nematode management measures such as disease free seeds, resistant varieties, crop rotation, intercropping, biological control and chemical control should be practiced to maintain the population of cyst nematode below economic threshold level.

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding Alternaria black spot of cruciferous vegetables, incited by different species of Alternaria, remains an increasing threat to Brassicaceae crops throughout the world, including Poland. Brassica plants are attacked by conidia of A. brassicae (Berk.) Sacc., A. brassicicola (Schw.) Wiltsh., A. raphani Groves & Skolko, and A. alternata (Fr.) Kreissler. The pathogens have a wide spectrum of hosts, such as head cabbage, Chinese cabbage, cauliflower, broccoli, and other crucifers including cultivated and wild grown plants. Alternaria pathogens usually cause damping-off of seedlings, spotting of leaves of cabbages, blackleg of heads of cabbages, and spotting of cauliflower curds and broccoli florets. In oilseed rape, A. brassicae is the dominant invasive species, while in the cruciferous vegetables, both species, A. brassicae, and A. brassicicola are encountered. Infected seeds with spores on the seed coat or mycelium under the seed coat are the main means of distribution for these pathogens. The fungus can overwinter on susceptible weeds or crop debris and on seed plants, as well as on stecklings. Methods for disease prevention and control are based on combining agricultural management practices with chemical control. Using disease-free seeds or seeds treated with fungicides can greatly reduce disease incidence. After appearance of the first symptoms of disease, stringent fungicide spray program is an effective way to reduce losses. Many authors seem to agree, that the most economically feasible method of disease control is the development of resistant Brassicaceae crops varieties, as transgenic approach proved unsuccessful. Due to our increasing understanding of pathogen-host plant interactions, identification of resistance sources, and assessment of the resistance trait inheritance mode, breeding programs of Brassica crops for Alternaria resistance can be enhanced. This is of particular importance since recent years experience dynamic development of ecological and integrated plant production with an emphasis on plant biotic stress resistance. Highly resistant genetic resources have not been reported in Brassica cultivated species, although some varieties differ in their resistance/susceptibility level. Strong cross-incompatibility, polygenic background of the resistance (additive and dominant gene interactions), as well as the differences in ploidy between the Brassica species of interest, render the transfer of Alternaria resistance from the wild species into the cultivated forms difficult. Additionally, it is often connected with employment of in vitro hybridization techniques, including somatic hybridization, embryo and ovary rescue, or protoplast fusion.

IDENTIFICATION OF BACTERIA INFECTING MUNG BEAN SEEDLINGS USED IN ROOTING BIOASSAYS

Mung bean (Vigna radiata (L.) R. Wilcz.) cuttings are used in rooting bioassays, and nonexperimental variability must be rigorously controlled to obtain meaningful results. This study was conducted to document bacterial disease problems of mung bean and identify the causal organisms. `Berken' seeds were surfaced sterilized and aerated 24 hr before sowing. Nine-day-old seedlings were used in rooting bioassays. Up to 10% of the seedlings and 17% of the cuttings had collapsed stems or wilted leaves. A white and two yellow (Y1 and Y2) bacteria were isolated from diseased cuttings and used in subsequent pathogenicity tests. The Y2 isolate was nonpathogenic. Stems of healthy mung beans inoculated with the white isolate turned brown and collapsed 2 days after inoculation, whereas leaves of plants inoculated with the yellow isolate wilted after 7 days. Standard biochemical and physiological tests revealed that the white isolate was Pseudomonas syringue pv. syringae van Hall and the yellow isolate was Curtobacterium flaccumfaciens subsp. flaccumfaciens (Hedges) Collins and Jones. This research is the first report of a disease in mung bean caused by P.s. pv. syringae. These results demonstrate the need or disease-free seeds being used in bioassays since both pathogens were seed-borne.