Determination of malathion's toxic effect on Lens culinaris Medik cell cycle.

The present study aimed to determine the toxic effect of malathion pesticide on root growth, cell division and the chromosomal abnormalities frequency using the L. culinaris test. Initially, the lentil seeds were subjected to different doses of malathion (0.0 0.5, 1, 2.5, 5, 10, 15, 20, 25 and 30 mgL-1) and during 24, 48, and 72 h, the root length was measured. Subsequently, at 72h, the mitotic index, mitotic inhibition, and cellular abnormalities were calculated for all treatments. According to the obtained results, it was visualized that the root growth was inversely proportional to the concentration of malathion at all times of exposure. After 72h of exposure, the lowest values of the mitotic index and inhibition were presented at malathion concentrations 20, 25 and 30 mgL-1. Additionally, micronuclei cell abnormalities, metaphase sticky chromosomes, split chromosomes, nuclear lesions, irregular anaphase, anaphase bridges, binucleated cells, absence of nucleus and telophase bridge were observed. Finally, Malathion induced mitodepressive and cytotoxic effects in the meristematic cells of the L. culinaris root tip. A high frequency of abnormality was found in the micronuclei, which represented an indicator of a high degree of toxicity at the cellular level.

Cytogenotoxic effect of propanil using the Lens culinaris Med and Allium cepa L test.

Propanil can produce methemoglobinemia, hemolytic anemia, hepatotoxicity, metabolic disorder and nephrotoxicity. It also has a genotoxic effect, although it is not listed as a carcinogen and it continues to be applied excessively throughout the world. Consequently, in this study the cytogenotoxic effect of propanil was evaluated, using apical root cells of Allium cepa and Lens culinaris. In which, L. culinaris seeds and A. cepa bulbs were subjected to 6 treatments with propanil (2, 4, 6, 8, 10 and 12 mg L-1) and to distilled water as control treatment. Subsequently, the root growth was measured every 24 h for 3 days. Next, the mitotic index and cellular anomalies were determined. Whereby, decreased root development was observed in all treatments. Likewise, greater inhibition of mitosis was evidenced in L. culinaris compared to A. cepa. In addition, chromosomal abnormalities, such as nucleus absence, sticky chromosomes in metaphase and binucleated cells, were present in most of the treatments. Thus, the presence of micronuclei and the results of L. culinaris, indicate the high cytogenotoxicity of propanil and the feasibility of this species as bioindicator.

Evaluation of the cytotoxic potential of sodium hypochlorite using meristematic root cells of Lens culinaris Med.

The present investigation was designed to monitor the cytotoxic potential of Sodium Hypochlorite using lentil (Lens culinaris) as a bioindicator of toxicity. Sodium hypochlorite (NaClO), is a chemical compound that is used mainly for its disinfectant properties, its effect is widely toxic, which is why it is marketed in low concentrations and it is also a component in various products such as agrochemicals. In the present study the L. culinaris seeds were exposed to different NaClO dose 0, 0.2, 1, 3, 5 and 7 mg L-1 during 24, 48 and 72 h; timeslots in which the root growth was also studied. The cytotoxic potential of NaClO was determined by calculating the mitotic index (MI), calculating cellular anomalies (CA) and observing the longitudinal growth of the roots during the various time periods. The radicular growth was prolonged and it was observed that there was a greater growth at the dose of 1 and 7 mg L-1 in the time of 72 h. The cytotoxic effects could be analyzed in the mitotic index, since the higher the concentration, the lower the mitotic index, as observed in the dose of 7 mg L-1 where a reduction of the mitotic index of the meristematic cells is observed. The results indicate that NaClO has a cytotoxic effect that induces various types of chromosomal abnormalities. This indicates that Sodium Hypochlorite has a cytotoxic effect according to the increase in its dose. Therefore, Lens culinaris turned out to be a kind of appropriate bioindicator to study the cytotoxic effects of various potentially toxic substances.

Evaluation of cytotoxic potential of chlorpyrifos using Lens culinaris Med as efficient bioindicator.

The aim of this study was to evaluate the cytotoxic effect of different concentrations of chlorpyrifos (CPF), using L. culinaris apical cells as a biological indicator. L. culinaris seeds were exposed to different concentrations of chlorpyrifos (0, 1, 3, 5, 7, 8, 10 and 15 mg L-1) and a control solution based on distilled water. Subsequently, root growth was measured during 24, 48 and 72 h. Therefore, the mitotic index (MI) and the number of cellular abnormalities were determined at 72 h. According to the obtained results, a decrease in root size was observed in the concentrations of T5 (8 mg L-1) and T6 (10 mg L-1). On the other hand, it was evidenced that, through all the evaluated concentrations, the inhibition of mitosis in the concentrations of T5 (8 mg L-1), T6 (10 mg L-1) and T7 (15 mg L-1) was greater than 50%. Additionally, a variety of chromosomal abnormalities were reported, such as Micronuclei, sticky chromosomes in anaphase, chromosome disruption, irregular anaphase, nucleus absence, nuclear lesions, chromosomes grouped in metaphase, anaphase bridges, metaphase sticky chromosomes, present in all concentrations evaluated. Consequently, the presence of micronuclei in the concentrations of 8 mg L-1, 10 mg L-1 and 15 mg L-1 indicates that the CPF is a highly cytotoxic substance to L. culinaris. Therefore, L. culinaris is a plant species that offers a feasible experimental model to be implemented in laboratory studies with the purpose to evaluate the cytotoxic effect of pesticides.

Cytotoxic evaluation of sodium hypochlorite, using Pisum sativum L as effective bioindicator.

The objective of this study was to evaluate the cytotoxic effect of different sodium hypochlorite concentrations, using apical root cells of P. sativum as a bioindicator. Initially, the seeds of P. sativum were exposed to different concentrations of sodium hypochlorite (0.1, 0.2, 0.4, 0.8, 1.6, 2 mg L-1) and to a control solution based on distilled water. Next, root growth was measured during 24, 48 and 72 h. Subsequently, the mitotic index (MI) and cellular anomalies (5000 cells per treatment) were determined at 72 h. According to the results obtained, a decrease in root growth was observed at concentrations of 0.4, 1.6 and 2 mg L-1. Likewise, it was evident that, among all the evaluated concentrations, an inhibition of mitosis higher than 50% was presented. Additionally, chromosomal anomalies were also generated, such as Nuclear notch, lagging chromosomes and Chromosomal break, which were present in all the concentrations evaluated. In addition, the presence of micronuclei at concentrations of 2.0 and 1.6 mg L-1 indicate that sodium hypochlorite is a highly cytotoxic substance. Therefore, P. sativum is a specie that offers a feasible experimental model to be implemented in the laboratory with the aim to evaluate the cytotoxic effect of any cytotoxic substance.

Evaluación de diferentes medios de cultivo in vitro en el desarrollo de híbridos de Phalaenopsis (Orchidaceae) / Evaluation of different in vitro culture media in the development of Phalaenopsis hybrid (Orchidaceae)

Los híbridos de Phalaenopsis tienen una gran importancia económica a nivel mundial, como flor cortada y planta ornamental, debido a sus flores vistosas y a la capacidad de adaptación a diferentes condiciones ambientales. Las técnicas de cultivo in vitro resultan indispensables para mejorar la eficacia germinativa, el crecimiento y desarrollo de orquídeas con fines comerciales e investigativos. En esta investigación se determinó el medio de cultivo más apropiado para la germinación in vitro de un híbrido de Phalaenopsis. Inicialmente se evaluó la viabilidad de las semillas utilizando la prueba de tetrazolio (TZ). Las semillas se desinfectaron y se cultivaron aplicando el método de la jeringuilla. El porcentaje de viabilidad en promedio fue de 92,2 % (P≤ 0,05: Tukey HSD), con un porcentaje de germinación entre todos los medios de 95,1 % (P≤ 0,05: Tukey HSD). El medio de cultivo más eficiente para la germinación de híbridos de Phalaenopsis a las 18 semanas de cultivo fue el Murashige & Skoog (MS) suplementado con agua de coco, y jugo de piña con diferencias estadísticamente significativas (P≤ 0,05: Tukey HSD), con respecto a los demás medios de cultivo, contribuyendo de esta manera al uso de componentes orgánicos con el fin de mejorar la germinación y desarrollo de Phalaenopsis.

The Phalaenopsis hybrids have a significant economic importance throughout the world, as ornamental flower or plant. It is because of its attractive flowers and its adaptation capacity into different environments. The different culture media in vitro are vital to improve the efficacy of germination, growing and development of the Orchids for commercial and research purposes. In this research, the most appropriated medium for in vitro propagation of Phalaenopsis hybrid was determined. At first, the seeds viability was evaluated by using tetrazolium test (TZ). The seeds were disinfected and cultivated by means of the syringe method. The viability percentage average was 92.2 % (P≤ 0.05: Tukey HSD), with a percentage of germination of 95.1 % (P≤ 0.05: Tukey HSD) in all the environments. The most efficient culture Medium for Phalaenopsis hybrid phenological development, at 16 weeks, was Murashige & Skoog (MS). Coconut water and pineapple juice were used as supplement showing statistically significant differences (P≤ 0,05: Tukey HSD), in comparison with the other culture media, contributing this way to the usage of organic components, which will be employed to improve the germination and development of the Phalaenopsis.

Evaluación del efecto de dos suplementos orgánicos en la germinación in vitro de orquídeas nativas de la provincia de Pamplona, Colombia / Evaluation of the effects of two organics supplements on in vitro germination of native orchids in the province of Pamplona, Colombia

La continua pérdida de hábitat de las orquídeas nativas en Colombia, y las limitaciones de la germinación en estado silvestre, ha dado lugar a un mayor énfasis en la conservación de las orquídeas. Por consiguiente el cultivo in vitro es una herramienta alternativa para la conservación de especies en peligro de extinción. En esta investigación se evaluó la germinación asimbiótica y la formación de plántulas de semillas de orquídeas, de las especies Prosthechea vespa Vell. y Sobralia klotzscheana Rchb. f. en el medio de cultivo Murashige y Skoog (MS) con dos suplementos orgánicos (jugo de piña y agua de coco). Se colectaron cápsulas maduras de las especies P. vespa y S. klotzscheana, en la región nororiental de Colombia (Pamplona, Norte de Santander) y se determinó la viabilidad de las semillas con la prueba de Tetrazolio. Las semillas se desinfectaron y se sembraron con el método de la jeringuilla. La viabilidad de las semillas fue del 87,2% en P. vespa y 80,6% en S. klotzscheana. El porcentaje de viabilidad corregido con respecto a la germinación fue mayor, entre 2,8% (P. vespa) y 0,5% (S. klotzscheana). Este estudio demostró que el medio MS suplementado con jugo de piña tiene una mayor respuesta a la geminación asimbiótica y formación de plántulas en las orquídeas P. vespa (22%) y S. klotzscheana (43%) con diferencias estadísticamente significativas (P≤0,05: Tukey HSD).

The continued habitat destruction of native orchids in Colombia and its germination limitations in the wild has led to greater emphasis of the species conservation, therefore to preserve endangered orchids in vitro culture is an alternative tool. This research evaluated orchid seeds asymbiotic germination and seedling formation of Prosthechea vespa Vell. and Sobralia klotzscheana Rchb. f. species in Murashige and Skoog (MS) culture medium with two organic supplements (pineapple juice and coconut water). Mature capsules from P. vespa and S. klotzscheana species were collected in the Province of Pamplona, northeastern region of Colombia and their viability with tetrazolium staining was determined. The seeds were disinfected and sown by the syringe method. The seeds viability were 87,2% in P. vespa and 80,6% in S. klotzscheana. The corrected percentage of viability compared to the germination was higher, between 2,8% (P. vespa) and 0,5% (S. klotzscheana). This study showed that MS medium supplemented with pineapple juice has a greater response to asymbiotic germination and seedling formation in P. vespa (22%) and S. klotzscheana (43%) with statistically significant differences (P≤0,05: Tukey HSD).