Hot pepper (HP), Capsicum annuum (L.), is a solanum plant domesticated in Mesoamerica. It is currently widespread worldwide, and its uses are varied, such as an excellent flavoring, pigment base, and as a food resource with source of vitamins. The seven top world producers of HP are China, Mexico, Turkey, Spain, United States, Nigeria, and Indonesia. Mexico is producing about 623,238 t/year of fresh fruits in 136,398 ha; Colima produced 17,181 t in 676 ha, with a mean of 27 t·ha-1. The culture of HP in Colima is facing certain limitations in showing its productive potential, such as maintaining fertile and well-drained soils, and constant soil moisture; being weed-free during the first weeks after transplanting; and sustaining plant uniformity into transplantation. Transplantation is made in seed beds, but there is a lack of scientific evidence on shade requirements in the seed nursery to accelerate and improve plant quality for transplanting, and to impact on fruit yield. The aim was to evaluate the effect of levels of shading on the germination and vegetative development of `Serrano' HP under greenhouse conditions. Four levels of shading were evaluated using mesh fabrics to produce 90%, 75%, and 50% shade, and a control without shading on the seed beds. A completely randomized design with four treatments and four replications was used. The shading treatments reduced the germination period in about 1 day, increased the percentage of germination with a range between 1.75% and 3.25%; increased the plant height 0.83, 2.85, and 4.38 cm at 3, 6, and 10 days post-emergence; increased the root biomass about 0.01 g/plant, and 0.24 g of fresh foliage with the 90% shade compared with the control. Overall, a better agronomic performance of `Serrano' HP was obtained with 90% shading.
Marcelino Bazán-Tene, Jaime Molina-Ochoa, and Enrique Alejandro Bracamontes-Ursúa
Juan Manuel González-González*, Marcelino Bazán-Tene, Francisco Radillo-Juárez, and Jaime Molina-Ochoa
Plants in the genus Ficus are one of the most used in the ornamentals. it is also used for plant handcrafting such as braid, cylinders, and wall rockets, using a single plant or braiding some plants. The ficus are commonly asexually propagated by slip or shoots. There is the possibility to graft and to obtain plants with two levels of foliage, combining the color and texture. The objective of this research was to evaluate the grafting compatibility of varieties of Ficus benjamina, such as: Vivian, Winter green, and Antillean (green color) grafted on the variety Profit (white color) used as rootstock. The study was carried out under environmental conditions of the Mexican Dry Tropic in Tecomán, Colima, Mexico. The grafting method was by whip or tongue approximation. Bud sticks of the four varieties ≈70-cm long were used as scions. They were previously rooted in polyethylene bags containing 1.5 kg of coconut fiber used as rooting substrate. The rootstocks were grown long in soil until 1.5 m and when they reach similar diameter to the scions. The grafting height and diameter was ≈50-60 cm, and 2-2.6 cm, respectively. Five grafted plants were used as experimental unit, and the treatments were distributed in a completely randomized design with four replications. The variables estimated were: number of leaves after 28 and 35 days post-grafting, and percentage of grafting at 28 and 35 days post-grafting. The tree varieties were compatible with the rootstock, and no differences were obtained between the treatments (Tukey test P< 0.05); both three varieties exhibited 75% of grafting success, and `Antillean' had higher number of leaves, but the three varieties were statistically similar.
Francisco Radillo-Juárez*, Marcelino Bazán-Tene, Jaime Molina-Ochoa, and Edgar Damián Rolón-Vejar
The production of `Jalapeño' hot pepper has been increased in the last 10 years in about 6.21% during the period between 1992-2003, with a growing rate of 72%. In Mexico, is an important produce, because it is considered part of the traditional Mexican diet as well as its high productive level. One of the most frequent problems in this crop is the low production of fresh fruits caused by an inadequate fertilization. The objective of this research was to evaluate the effect of four fertilization formulas on the yield of fresh fruit of hot pepper variety Jalapeño cultivar Grande under irrigation conditions The evaluated formulas were (N-P-K-S): 1) 58-51-35-12 (control); 2) 78-68-46-16; 3) 97-85-58-20; and 4) 117-102-69-24. Treatments were distributed under a completely randomized block design with four replications. The formula 117-102-69-24 showed the highest values in the plant height and number of fruits with 62.5 cm, and 48 fruits, respectively. This formula also showed the highest values on equatorial and longitudinal diameters, and fruit weight with 3.36 cm, 11.26 cm, and 33.66 g, respectively. The total yields per plant and per hectare was 1.54 kg; and 38.22 t was obtained with the formula 117-102-69-24. The formula with the higher units of each element showed the best performance and exhibited the highest yield of fresh hot pepper, it was more productive than the control treatment commonly used by the hot pepper growers in Colima.
Mario Orozco-Santos, Javier Farias-Larios, J. Gerardo López-Aguirre*, Emilio Sánchez-Arévalo, and Jaime Molina-Ochoa
In Central Pacific region, Mexico, are cultivated around 17,000 ha of cucurbitaceous. This crops are affected by wilt, this disease is caused by Fusarium oxysporum (F.o.) Schlechtend. Some farmers are using resistant varieties to this disease, but resistance is different to each cultivar. Soil fumigation is other way to control this pathogen. Soil solarization is a new alternative for Fusarium oxysporum control. The objective of this research was to evaluate the effect of soil solarization on Fusarium oxysporum for wilt control in muskmelon crop in Colima State. The experiment was carried out under field conditions, using Cantaloupe melon (Cucumis melo L.) Cv. Ovation, in Ixtla-huacán municipality during November-December. Clear plastic was used (thickness 110). Evaluation of solarization periods were 0, 10, 20, and 30 days. Experimental design was full random blocks, with four replications. Evaluated variables were: soil temperature at 5-,10-, and 20-cm soil depth, propagule number of Fusarium oxysporum in soil, wilt incidence and yield. For determine Fusarium oxysporum survival, a strain isolated from infected plants was used. Fungi was introduced in cloth bags, containing 10 gr of sterile sand with 10 mL of a suspension of 19,000 conidia/mL. Later were introduced four cloth bags per treatment at 5-,10-, and 20-cm soil depth. When plants were harvested, was taken the sick plants percentage. Results shown that soil solarization periods had not an effect on the propagule number at the soil depth for the solarization periods. Also soil solarization had not and effect on plant yield. Is necessary to do the same experiment during different season, as June-July or September-October, to have a higher soil temperature and humidity.
Mario Orozco-Santos, Javier Farías-Larios, Jaime Molina-Ochoa, and José Gerardo López-Aguirre
Development of resistance to chemical pesticides has been reported in about 150 plant pathogenic species, mostly fungi. Biocontrol of plant pathogens is an alternative to chemical pesticides. Actually, there are products formulated with beneficial microorganisms, such as mycorrhizal fungi, rhizobacteria, antagonistic fungi, and others. The objective was to evaluate the development of Fusarium oxysporum f. sp. melonis (FOM) on melon plants inoculated with commercial biological formulations based on beneficial microorganisms. Twelve treatments were evaluated: T1) VAM media nursery + FOM; T2) Hortic Plus + FOM; T3) BioPak F + FOM; T4) Glomus intraradices + FOM; T5) FOM; T6) control; T7) VAM media nursery; T8) Hortic Plus; T9) BioPak F; T10) Glomus intraradices; T11) FOM + Mancozeb wp80; and T12) FOM + BioPak F. The melon cultivar used was `Colima' (Peto Seed Co.). Seeds were planted in Styrofoam growing containers containing coconut fiber powder as substrate. One seed was planted per cell and maintained until transplanting. Plants were transplanted to pots containing sterile soils 13 days postemergence. Inoculation of treatments with Fusarium was made with a concentrated suspension at 1 × 106 conidia/mL. For inoculation with beneficial microorganisms, manufacturer specifications were followed. A completely randomized design with 12 treatments and 12 replications was used to estimate the incidence of Fusarium, number of leaves, leaf area, root biomass, and percentage of roots colonized by mycorrhizal fungi. Overall, T10 showed the best behavior in all variables. Inoculation of cantaloupe plants with Fusarium affected their performance, but those treatments including mycorrhizal fungi enhanced their performance withstanding the damage by Fusarium.
Mario Orozco-Santos, Javier Farías-Larios, José Gerardo López-Aguirre, and Jaime Molina-Ochoa
In the Pacific Central region of Mexico, 17,000 ha are cultivated with cucurbitaceous crops. Most are affected with wilt caused by Fusarium oxysporum f. sp. melonis. The use of fungicides, such as methyl bromide, for soil disinfecting is a common practice; however, this practice has adverse effects on beneficial microorganisms, and soil is rapidly infected again. Soil solarization is a sustainable alternative, and it is feasible to be integrated in production systems. It has been used to delay the establishment of symptoms and to reduce the incidence of fusarium wilt in watermelon fields. The objective of this study was to evaluate the effect of soil solarization and methyl bromide on control of fusarium wilt on cantaloupes in western Mexico. The experiment was conducted in the Ranch Fatima located in the municipality of Colima. Severe wilt incidence and damage were previously observed in the cantaloupe cultivar Impac. Dripping irrigation system was used. Treatments established were: 1) solarization; 2) solarization + vermicompost; 3) solarization + chemical products [methyl bromide + chloropicrine (98/2%)]; 4) methyl bromide; and 5) control (without solarization or chemicals). Soil solarization was done during the 6 months before planting using clear plastic mulching (110 thick). A completely randomized design with five treatments and four replications was used. Six beds, 10 m long and 1.5 m wide, were used as experimental unit. Variables registered were: leaf area, leaf number, dry and fresh weight, propagule number, soil temperature, number of diseased plants showing wilt symptoms, and yield. Treatments 1 and 3 exhibited the highest agronomic variable values, and best control of fusarium wilt and fruit yields.
Mario Orozco-Santos, Javier Farías-Larios, Jaime Molina-Ochoa, and José Gerardo López-Aguirre
Melon wilt (MW) is one of the main diseases affecting the cucurbitaceous crops in the Pacific Central region of Mexico. The use of resistant varieties is the most effective strategy to reduce the damage caused by MW; however, variety performance depends on the fungal race occurring in the field. The use of fungicides, such as benzimidazols and methyl bromide, is a common practice, but there are contamination concerns, and a search is on for alternatives to diminish the negative effects on the agro-ecosystem. The aim was to determine the effect of the application of soil amendments and mulching on the incidence of MW, and on melon yield. Soil amendments incorporated were: rice straw (3 t·ha-1); compost 1, prepared with chicken and bovine manure, and banana and orange wastes (5.7 t·ha-1); compost 2, prepared with bovine and horse manure, coconut wastes and grasses (8 t·ha-1), vermicompost (3 t·ha-1), and a control. All treatments were established using transparent mulching during 21 days. The number of MW propagules in amended soils were similar at 5, 10, and 20 cm deep, but the percentage of diseased plants was higher (4.5%) in the control, which could be caused by the incidence of other fungi propagules, perhaps antagonistic, that contributed in diminishing the MW when compared with the control. The fruit weights and fruit sizes were not different between treatments on small (21–30 sizes), medium (15–18 sizes), and large (9–12 sizes), but total fruit numbers were 1.15-, 1.07-, 0.99-, and 1.09-fold higher when compared with the control. The application of soil amendments affected the antagonistic fungal populations even when it did not affect the cantaloupe yield. We suggest that soil amendments will improve soil fertility and increase melon yields, and studies are currently running.
Roberto Lezama-Gutierrez, Jaime Molina-Ochoa, Oscar L. Contreras-Ochoa, Martin Gonzalez-Ramirez, Oscar Rebolledo-Dominguez, and M. Lopez-Edwards
The susceptibility of third-instar larvae of Anastrepha ludens (Loew) to the entomopathogenic nematodes Steinernema carpocapsae (Weiser) (All and Tecomán strains), S. feltiae (Filiipjev), S. glaseri (Steiner) (NC strain), S. riobrave (Cabanillas, Poinar & Raulston), and Heterorhabditis bacteriophora Poinar (NC, Patronato, and Tecomán strains), was evaluated under laboratory conditions. Sterile distilled water (1.0 mL) with 4000 infective juvenile nematodes were applied on 300 g of moistened sterile soil into 1000-mL pots, and 20 third-instar larvae were placed on the soil surface, 1 mL of distilled water without nematodes was applied as control. Each nematode treatment was replicated four times. After nematode application, pots were incubated at 25 °C. Mortality of larvae and pupae was evaluated 6 and 12 d after inoculation. Cadavers of larvae and pupae were dissected and examined for the presence of nematodes. Our results showed that Mexican fruit larvae were susceptible to entomopathogenic nematodes. S. riobrave and S. carpocapsae All strain caused 90% of larval and pupae cumulative mortality, H. bactetiophora NC strain and S. feltiae killed more than 80%, whereas H. bacteriophora Tecomán and S. glaseri caused a 52.5% mortality. These results suggest that the nematodes S. riobrave and S. carpocapsae All strain have a potential as biological control agents against A. ludens.
Alejandra Guadalupe Zamora-Solís, Marcelino Bazan-Tene, Javier Farias-Larios, Jose Gerardo López-Aguirre, and Jaime Molina-Ochoa
Distribution of salinity and sodicity through the world is around 80 thousand million km2. To this quantity, we must add 10 million ha of irrigated lands that are abandoned each year due to such adverse effects on irrigation as salinity and/or alkalinity. Easily available substrates, such as glucose, increase the microbial activity to imprpove soils; for example, pH decreases because of a high production of some metabolites, such as carboxylic acids and hydro phenolics group. We carried out a study to evaluate the effect of glucose application on tomato plant (Lycopersicum esculentum Mill.) growth in saline soil. The experiment was done under greenhouse conditions. Soil samples were taken from 0–20-cm depth at the “El Chococo” ranch (lat. 18°47'N; long. 103°55'W). Treatments imposed were: 2% (T1), 4% (T2), and 6% (T3) glucose and a control without glucose (T0). Soil with treatments was incubated at ambient temperature for 40 days. Tomato seeds were germinated for 30 days and later transplanted to plastic bags that contained treatments. After transplant, tomato plants were grown for 40 days and then evaluated for plant height, dry and fresh weight, aerial and radicular biomass, and foliar area. Treatments were distributed under randomized design, and Tukey's (0.05) separation means were done. When the glucose percentage was increased, the soil pH decreased 8.50, 8.0, 7.70, and 7.60 in T0, T1, T2, and T3, respectively, but electrical conductivity increased. The highest values of parameters evaluated in plants were measured in treatment T3, and all the plants died in treatment (0).
Orlando Javier Torres-Meza, Marcelino Bazan-Tene, Javier Farias-Larios, Jose Gerardo Lopez-Aguirre, and Jaime Molina-Ochoa
Low organic matter in soil is a large problem in crop production around the world because it affects physical, chemical, microbiological, and morphological properties. On the other hand, regions with agro-industry generally generate waste that can cause some level of contamination. Therefore, it is necessary to find some use for this kind of waste. This study was done to evaluate the effect of lemon industrial waste on tomato (Lycopersicum esculentum Mill.), growth in a saline soil. The experiment was conducted under greenhouse conditions. Soil samples were taken from 0- to 20-cm depths at the El Chococo ranch, located at 18°47'N and 103°55'W. Four treatments were imposed: 0 (0), 600 (1), 1200 (2), and 1800 (3) m3/ha. Soil in treatments was incubated at ambient temperature for 40 days. Tomato seeds were germinated for 30 days and later transplanted to plastic bags containing treatments. After transplant, tomato plants were grown during 40 days, after which was measured: high plant, dry and fresh weight, aerial, and radicular biomass and foliar area. Treatments were distributed under randomized design, and Tukey's (0.05) separation means was performed. Organic matter, pH, and CE in soil before treatment application was 1.01%, 8.5, and 7.6 dS/m respectively (in 1:5 soil: water ratio). After application, OM increased until 3.7% in treatment 3. pH and CE decreased to 5.5 in treatment 2, and 1.57 dS/m in treatment 0. All data measured in plants had the highest values in treatment 1, and all plants died in treatment 0. We believe that is necessary to do this experiment in the field to obtain additional data.