Chili Seedlings Research Articles

Seed and seedling quality of three chilis (Capsicum annuum L.) native to Oaxaca, Mexico

ABSTRACT: The diversity of chilis in Oaxaca is one of the most extensive in Mexico. Growers select seeds in the traditional manner; information on its quality is unknown. The aim of this research was to compare the physical and physiological quality of seeds and seedlings of three native types to chili (Huacle, De agua and Pasilla) and of the commercial Green pepper as control. Fifteen variables were evaluated in seed and twelve in seedlings. The laboratory experiments were established under a completely randomized design. Means of the variables were compared using the Tukey test (α=0.05). Results showed that Pasilla chili had the highest values in seed size and weight, which was 1.44 g heavier than the control and 2.09 to 3.73 g higher than native types. Haucle chili and green pepper had a 90% germination rate, while chili De agua and Pasilla chili had germination rates of 51 and 38%, respectively. Huacle chili had the highest germination rate index (29.89) and seedling vigor index (992.25). The top highest values of number of normal seedlings were obtained in the control and Huacle chili seedlings (72 and 88%); also, the latter had the longest plumule (3.36 cm) and radicle (7.67 cm) values. Both Huacle and Pasilla chili seedlings had larger values in height, stem thickness, number of leaves, leaf area and slenderness index than De agua and Green pepper. Huacle chili had good physical and physiological quality similar to the seeds of the commercial Green pepper.

Biofertilizantes de rizobacterias en el crecimiento de plántulas de chile Poblano

El chile Poblano (Capsicum annuum L.) es una variedad muy consumida en nuestro país, pero existen varios problemas que afectan su cultivo y producción. Considerando lo anterior, el objetivo de esta investigación fue elaborar y comparar el efecto de dos biofertilizantes con rizobacterias en el crecimiento de plántulas de chile Poblano. La investigación se realizó en el Colegio de Postgraduados, Campus Montecillo en los años 2015-2016. El trabajo se desarrolló en tres etapas: 1) selección de medios de cultivo y dinámica de crecimiento de cuatro cepas de rizobacterias; 2) elaboración de dos bioformulaciones utilizando como acarreadores perlas de alginato y turba; asimismo, se evaluó la viabilidad de las rizobacterias por cinco meses; y 3) evaluación del efecto de las bioformulaciones en la promoción del crecimiento de plántulas de chile Poblano. Las cepas de Serratia presentaron el mayor crecimiento en el medio de cultivo TBS, mientras que las cepas de Pseudomonas tuvieron un alto crecimiento en caldo Luria-Bertani. La fase estacionaria de las cepas de Pseudomonas se alcanzó entre las 24-48 h y la de las cepas de Serratia entre las 12-44 h. La vida de anaquel de las dos formulaciones se mantuvo de 1 x 1012 a 1 x 109 UFC durante cinco meses. La aplicación de perlas de alginato en los semilleros estimuló el crecimiento de las plántulas hasta 35% con respecto al testigo. La aplicación de biofertilizantes a base de perlas de alginato y turba es una buena opción para promover el crecimiento de plántulas de chile.

Rhizobacteria Bacillus spp. induce resistance against anthracnose disease in chili (Capsicum annuum L.) through activating host defense response

Bacillus sp. BSp.3/aM, a beneficial rhizobacteria, was analyzed for the ability to improve plant health of chili by suppressing anthracnose disease. In the dual culture assay, the bacterium Bacillus sp. BSp.3/aM was found inhibitory to Colletotrichum capsica (6 mm). Further, upon seed priming, it reduced the seed-borne incidence of C. capsici (2%) and improved seedling vigor (1374 ± 7.15 vigor index) and germination (98 ± 0.57 %) of chili seedlings. Under greenhouse conditions, seed priming resulted in reducing the anthracnose disease incidence up to 20%. Induction of resistance against invading pathogen is through enhancing the activities of defense-related enzymes and higher accumulation of phenolic compounds in the host plant. The activity of phenylalanine ammonia-lyase (PAL; 95 units) was more at 48 hpi; peroxidase (POX; 6.49 units) at 24 hpi; polyphenol oxidase (PPO; 5.81 units) at 24 hpi and lipoxygenase (LOX; 9.9units) at 24 hpi. Maximum accumulation of the phenolics and chitinase accumulation was observed in BSp.3/aM + pathogen treated seedlings 120 hpi (94.7 μg/g tissue) and at 96 hpi (9.36 units), respectively. Thus, increased activities of defense-related enzymes (PAL, POX, PPO, LOX, and chitinase) correlated well with the decreased anthracnose incidence. Induced systemic resistance (ISR) mediated by PGPR was due to the upregulation of defense-related enzymes and by the accumulation of phenolic compounds.

Characterization of the antifungal activity of three rhizobacterial strains against Rhizoctonia solani

In this study, three rhizobacterial strains were characterized by their ability to inhibit Rhizoctonia solani and tested in chili (Capsicum annuum L.) seedlings. Strains A46 and P61 were identified as Pseudomonas tolaasii, and S108 as Rhanella aquatilis. In the dual culture tests, all the strains inhibited the radial growth of R. solani. None of the three strains produced chitinases or volatile compounds, but they were found to produce siderophores. However, this last characteristic was not responsible for the rhizobacterial inhibitory effect on the growth of R. solani, other bacterial metabolites were possibly involved. The bacterial filtrates added to the potato dextrose agar medium (PDA) in a 3:7 ratio had significant antifungal activity, being the filtrate from strain S108 the one that showed the highest effect, with 56% fungal inhibition. The co-culture of strain A46 with the phytopathogenic fungi in potato dextrose broth (PDB) increased the antifungal activity of the rhizobacterial filtrate. The application of the rhizobacterial strains to Serrano chili decreased the R. solani-related mortality rate in seedlings; particularly, S108 had the greatest effect, which was similar to the fungicide effect. This study showed that the S108 strain has potential as a biofungicide to control R. solani in chili seedlings.

Potensi Cendawan Endofit sebagai Pengendali Hayati Penyakit Busuk Pangkal Batang (Phytophthora capsici) pada Bibit Cabai

Stem rot disease caused by Phytophthora capsici is an important disease on chilli. Eight endophytic fungi that had been isolated and screened based on pathogenecity test were further tested for their potential as the biological control agent of the stem rot disease of chilli. The endophytic fungi suspension was applied twice during the trial. The first application was on 100 seed lot, by soaking them in 100 mL of suspension. The second application was on the 3 weeks-old chili seedlings by drenching them with 10 mL suspension per plant. The concentration of endophytic fungi in the suspension was 2.8 × 106 cfu mL-1. The disease intensity and AUDPC value were measured for 4 weeks after the pathogen inoculation. The growth inhibition test of P. capsici was performed in vitro and the colonization abilities of endophytic fungi were observed at 4 weeks-old chilli seedlings. Eight endophytic fungi inhibited the growth of the P. capsici, and two of those isolates namely Penicillium strain MAG1 and Penicillium strain PAB2 showed antibiosis mechanism. Endophytic fungi has the ability more to colonize at the root (26–60%) than in the stem (20–40%). Fusarium strain MAGR1 has the highest level of endophytic colonization i.e. 60% compared to others. Based on in vivo assay, six endophytic fungi isolates, i.e. Fusarium strain MAGR1, Penicillium strain MAG1, Penicillium strain PAB2, sterile hyphae HAJ1, sterile hyphae HAJ2, and sterile hyphae PBG7, showed the potency to control stem rot disease with inhibition level of 25.5–35.5%

Caracterización in vitro de rizobacterias y su antagonismo con hongos causantes del damping off en chile


 
 
 La producción de plántulas de chile (Capsicum annuum L.) en almácigos es afectada por la enfermedad conocida como “damping off”. Su prevención se hace regularmente mediante fungicidas, cuyos efectos sobre los hongos causantes de esta enfermedad no son siempre efectivos, pero representan problemas de tipo ambiental. Ante esta situación, el control biológico adquiere mayor relevancia. En el presente trabajo se aislaron tres cepas de hongos fitopatógenos del género Fusarium spp. (FP, FN y FA; por los colores púrpura, naranja y amarillo, respectivamente). En cuanto a cepas bacterianas, se seleccionaron 18 cepas de rizobacterias (B), las cuales fueron confrontados in vitro con las tres cepas de Fusarium y una de Rhizotocnia (R). La cepa B23 fue la más eficiente en la inhibición del crecimiento de los fitopatógenos estudiados, al reducir el crecimiento de FP, FN y FA (50, 44 y 47%, respectivamente) y de R (56%); la producción de AIA varió entre 1.24 y 11.32 μg mL-1, la mayor solubilización de fosfato inorgánico (104 μg mL-1) se obtuvo con B8. Al evaluar el efecto de B7, B9, B15 y B23 sobre la supervivencia de plántulas de chile inoculadas con Fusarium sp. y Rhizotocnia sp., se observó que las cepas B7 y B23 son las que tuvieron mayor efecto sobre la supervivencia de las plántulas durante los primeros 34 días, con valores de entre 80 a 100%, mientras que las plántulas control fue de entre 30 y 50%. Por otra parte, las cepas B8 y B9 se identificaron molecularmente como Pseudomonas chlororaphis; B7 y B14 como Pseudomonas sp.; B15 como Pseudomonas protegens y B23 como Bacillus sp. Los resultados muestran la potencialidad del uso de bacterias como promotoras del crecimiento y agentes de biocontrol de hongos causantes del damping off en plántulas de chile tipo “guajillo”.
 
 

Efecto de biocontrol e inhibición germinativa de Bacillus spp. sobre zoosporas de Phytophthora capsici

<p>El oomiceto<em> Phytophthora capsici </em>es un patógeno de importancia económica en los cultivos de tomate (<em>Solanum lycopersicum</em> L.) y chile (<em>Capsicum annuum</em> L.). El objetivo de este trabajo fue evaluar el efecto de inhibición germinativa y biocontrol de dos aislados del género <em>Bacillus</em> sobre zoosporas de <em>P. capsici</em>. Los aislados fueron identificados como <em>Bacillus amyloliquefaciens</em> y <em>B. thuringiensis.</em> En las pruebas <em>in vitro</em> de la germinación de zoosporas de <em>P. capsici</em>, los porcentajes de inhibición con suspensión celular de <em>B. amyloliquefaciens</em> y <em>B. thuringiensis</em> fueron significativos con 88.15 y 97.05% respectivamente, mientras que, los filtrados mostraron el 24.30% de inhibición. En el estudio <em>in vivo</em>, las plántulas de tomate tratadas con suspensión celular de <em>B. amyloliquefaciens</em> y <em>B. thuringiensis</em>, mostraron menor severidad de la enfermedad ocasionada por <em>P. capsici</em> con 22.22 y 27.78% respectivamente, respecto a lo observado en plántulas de chile donde se obtuvo valores de 61%. Las plántulas de tomate y chile tratadas con filtrados bacterianos, mostraron hasta 94% de severidad. Con suspensión celular de <em>B. amyloliquefaciens</em> y <em>B. thuringiensis</em> la eficacia de biocontrol fue 72 y 77% respectivamente, lo cual muestra que estos microorganismos pueden ser usados como agentes de biocontrol de <em>P. capsici</em> en plantas de tomate y chile.</p>

Screening of rhizobacteria from rhizosphere of healthy chili to control bacterial wilt disease and to promote growth and yield of chili

Abstract. Yanti Y, Astuti FF, Habazar T, Nasution CR. 2017. Screening of rhizobacteria from rhizosphere of healthy chili to control bacterial wilt disease and to promote growth and yield of chili. Biodiversitas 18: 1-9. Bacterial wilt on chili cause by Ralstonia solanacearum. This disease is important, causing plant death and significant yield losses. Biological control is desirable because control with other methods gives variable results. One of the important group of biological agent is the plant growth promoting rhizobacteria (PGPR). This group can control plant pathogens and enhance the growth and yield through direct and indirect mechanisms. The aim of this research was to obtain indigenous rhizobacterial isolates from rhizosphere of healthy chili, which are effective to control bacterial wilt disease and to promote plant growth as well as to increase plant yields. The rhizobacterial isolates were collected from healthy chili rhizosphere in endemic area of bacterial wilt at Banuhampu Sub-district, Agam District, West Sumatra, Indonesia. Screening method of rhizobacterial isolates to control bacterial wilt was based on in planta technique. This technique was consist of three steps, as follow: (i) Screening of 43 rhizobacterial isolates to induce the hypersensitive reaction on Mirabilis jalapa. (ii) Screening of 42 rhizobacterial isolates (from first step) to increase growth of chili seedlings and (iii) Screening of 20 selected rhizobacterial isolates (from second step) to control bacterial wilt on chili. R. solanacearum were inoculated on the 6 weeks chili plants using Two strains of rhizobacterial isolates from chili rhizosphere (RZ.2.1.AG1 and RZ.1.3.AP1) showed high potential for disease suppression and also increased growth and yield of chili.Keywords: chili, indigenous rhizobacteria, in planta technique, Ralstonia solanacearum, screeningAbbreviations: BCA = Biocontrol agent, HR = Hypersensitive reaction, IAA = Indole Acetic Acid, IRB = Indigenous Rhizobacteria, ISR = Induce systemic resistance, NA = Nutrient agar, PGPR = Plant Growth Promoting Rhizobacteria, R = Ralstonia, TZC = triphenyl tetrazolium chloride

Pengaruh Pemberian Ekstrak Daun Sirih (Piper betle L.) untuk Mengendalikan Damping-Off pada Tanaman Cabai (Capsicum annum)

Sclerotium roflsii is the causal agent of damping-off disease on pepper which difficult to control. The use of chemical pesticides cause several damage to the environment. The used of Piper betle leaves extract which is contains antifungal compounds becomes one of the solution. The aim of this study to obtain the optimum concentration of piper betle leaves extract and dipping periode of chili seed in leaves extract to control damping off disease caused by Sclerotium rolfsii . The study consists of two experiments. The first experiment was isolation and multiplication of damping off disease in chilli, this stage was conducted in laboratorium. The second experiment was performed to investigate effectivity of piper betle leaf extract to control damping off using dipping method, this stage conducted in Greenhouse. The study arranged in Completely Randomized Design (CRD) with single factor experimental design consist of 13 treatment, namely consentration of 0%, 40%, 60% and 80% Piper betle leaves extract (v/v) with 1 hour, 2 hour, and 3 hour dipping time. The result showed that Piper betle leaves extract of 60% with 1 hour dipping time had the best ability among the other treatment to control damping off disease cause of Sclerotium rolfsii in chili seedlings.

Biocontrol ofPhytophthora infestans, Fungal Pathogen of Seedling Damping Off Disease in Economic Plant Nursery

This research aims to control Seedling damping off disease in plants by using antagonistic actinomycetes against the causative fungi.Phytophthora infestanswas isolated from the infected tomato plant seedling obtained from an economic plant nursery in Amphoe Pak Chong, Nakhon Ratchasima Province, Thailand. The chitinolyticStreptomyces rubrolavendulaeS4, isolated from termite mounds at the grove of Amphoe Si-Sawat, Kanchanaburi Province, Thailand, was proven to be the most effective growth inhibition of fungal pathogens tested on potato dextrose agar. Tomato and chili seedlings that colonized with antagonisticS. rubrolavendulaeS4 were grown inP. infestansartificial inoculated peat moss. Percents of noninfested seedling in fungal contaminated peat moss were compared to the controls with uninoculated peat moss. InP. infestanscontaminated peat moss, the percents of survival of tomato and chili seedling were significantly increased () from 51.42 to 88.57 and 34.10 to 76.71 for theS. rubrolavendulaeS4 treatment, respectively. TheS. rubrolavendulaeS4 also showed high efficiency equivalent to fungicide, metalaxyl with no significant difference (). It was clearly demonstrated thatS. rubrolavendulaeS4 can prevent the tomato and chili seedling damping off disease in economic plant nurseries.

Control of Fusarium Wilt of Chili With Chitinolytic Bacteria

Biological control of plant disease using antagonistic microorganism has been obtaining much attention and implemented for decades. One of the potential microorganisms used in this strategy is chitinolytic bacteria. Utilization of this bacteria ranges from cell life, enzymes, genes, or other metabolites. In this study, we examined the ability of chitinolytic bacteria as a biocontrol agent of Fusarium wilt of red chili ( Capsicum annuum L.) seedlings. The ability of chitinolytic bacteria to suppress the disease was evaluated by soaking red chili seeds in the bacterial isolates solution for 30 minutes prior seedling. Percentage of seedling of treated chili seed at end of study (4-weeks) ranging from 46 to 82.14%. Relative reduction of the seedling damping-off was observed in all bacterial treatment ranged from 28.57 to 60.71%. Furthermore, manifestation of bacterial suppression to Fusarium wilt was also exhibited by increasing of seedling height (ranged from 7.33 to 7.87 cm compared to 6.88 cm) and dry-weight (ranged from 2.7 to 4.3 mg compared to 2.3 mg). However, no significant effect was observed in leaf number. Then, from all chitinolytic isolates tested, BK08 was the most potential candidate for biological control agent of Fusarium wilt in chili seedling.

Gamma Radiosensitivity Study on Chili (Capsicum annuum)

Induced mutation by gamma irradiation has been found to be a very useful technique for crop improvement. Apart from this, the proper use of induced mutation in plant breeding has become a profitable approach. This investigation was carried out to determine the LD50 and effect of gamma rays on germination, plant height, survival percentage, root length, root dry weight and shoot dry weight of seedlings derived from irradiated seeds of chili (Capsicum annuum). Seeds of chili were treated with 300, 400, 500, 600 and 800 Gy gamma rays at Malaysian Institute of Nuclear Technology (MINT). The treated seeds including control were sown in sand beds in size 4.6 x 0.7 m2 in a greenhouse at Horticulture Unit, UPMKB. Water was applied manually to maintain the soil moisture at field capacity as well as weed was manually controlled. The experiment was designed as 5 x 6 factorial in completely randomized design (CRD) with three replications. Lethal dose 50 % of population (LD50) was assayed. Observation showed that germination percentage, plant height, survival percentage, root length, root weight and shoot dry weight decreased with increasing dose of gamma rays. The 800 Gy gamma ray dose had a profound effect on these variables perhaps due to injury the higher doses may have caused to the seeds of chili. This resulted in poor growth and development of chili seedlings. The LD50 for chili (survival percentage) was estimated at 445 Gy. Loan contracts performance determines the profitability and stability of the financial institutions and screening the loan applications is a key process in minimizing credit risk. Before making any credit In general, higher gamma ray doses particularly 600 and 800 Gy had negative effect on the morphological characteristics of chili seedlings derived from irradiated seeds.

Influence of Rainshelter and Irrigation Method on Yield, Water, and Fertilizer Use Efficiency of Chili Pepper

Chili pepper (Capsicumannuum cv. Delicacy) was grown in single- and double-bed rainshelters and irrigated using furrow and drip irrigation to determine effect on yield and efficiency of water and nutrient application in the lowland tropics of southern Taiwan during the hot wet season. The experiment was laid out using a split-plot design with four replications. The main plots were rainshelters (single, double, open field) and the two irrigation methods (furrow and drip) were the subplots. Grafted chili seedlings were transplanted in double rows on raised beds at row spacing of 80 cm and plant spacing of 50 cm. The furrow-irrigated crop was applied with basal N-P2O5-K2O at the rate of 180–180–180 kg·ha-1 and 240–150–180 kg·ha-1 of N-P2O5-K2O as sidedressing. The drip-irrigated crop received half of the total rate applied for the furrow-irrigated crop. Significant differences (P < 0.05) in marketable yield were observed between rainshelter treatments. Highest yield (42.2 t·ha-1) was produced from the single-bed rainshelter, and crops grown under double-bed rainshelters produced the lowest marketable yield. Irrigation method did not significantly influence marketable yield, but crops grown under drip irrigation produced a higher yield than furrow-irrigated crops. Nutrient uptake by plants grown under drip irrigation was also higher (P < 0.05) than for furrow-irrigated crops. Water use efficiency was 60.7% higher in drip-irrigated plots. Results indicate that in high rainfall vegetable production areas, drip irrigation minimizes nutrient loss through leaching and maximizes efficiency of fertilizer use.