Opuntia ficus-indica (L.) Miller species grows in a wide range of environmental conditions, which implies a great variability in fruit yield and fruit ripening, among other aspects. Therefore, the aim of this research work was to identify the dependences of fruit yield per cladode on fruiting cladode fresh or dry matter, on fruiting cladode length or width, and on the ratio of fruiting cladode length to fruiting cladode width. The boundary-line approach and data from 60 terminal one-year-old fruiting cladodes and their 480 fruits of O. ficus-indica variety ‘Rojo Pelón’ from 20 six-year-old trees distributed at a density of 625 plants·ha-1 were used. Most fruiting cladodes with 144 g (minimum) to 964 g (maximum) of fresh matter had fruit yields of 409 g per cladode or even more, whereas most fruiting cladodes with 14.4 g (minimum) to 78.52 g (maximum) of dry matter had fruit yields of 409 g per cladode or even more. Fruiting cladode lengths from ≈21.8 cm to ≈38.4 cm, and fruiting cladode widths from ≈15.2 cm to ≈20.8 cm are linked to 90 % of their corresponding vertex (the estimated highest fruit yield per cladode). These measurements can be used to perform pruning in order to ensure high yields with fruits of acceptable fresh weight and suitable commercial size.

Vegetative propagation of garlic (Allium sativum) is the main route of virus transmission for this crop. However, insect-vector spread should not be ruled out. The aim of this study was to detect, by means of the ELISA test, the presence of five viruses in insects collected in garlic plants. The experiment was conducted during the fall-winter (2008-2009) cycle. Insect samples were taken on three dates: 45, 110 and 140 days after garlic sowing. Insect species identification was performed using a Zeiss (30X) stereomicroscope and the O’Brien and Wilson (1985) and Mound and Kibby (1998) taxonomy keys. The serology test for virus detection was the DAS-ELISA technique. Coat-protein virus antibodies were applied for the potyviruses: Leek yellow spot virus (LYSV) and Onion yellow dwarf virus (OYDV); for the carlaviruses: Garlic common latent virus (GCLV) and Shallot latent virus (SLV); and for the tospovirus: Iris yellow spot virus (IYSV). Of the 19 insect species identified, Thrips tabaci Lindeman tested positive in 18 samples for GCLV and in 2 samples for IYSV, and Collops quadrimaculatus tested positive in one sample for GCLV.

The guaje (Leucaena spp.), a leguminous plant with edible seeds, is a traditional resource underutilized by Mesoamerican peoples. The nutritional and nutraceutical value of the guaje is unknown despite being consumed by rural people today in mainly central and southern Mexico. The aim of this study was to assess the mineral, nutritional and antioxidant contents of the red guaje (L. esculenta Benth.) and green guaje (L. leucocephala Lam.) in order to contribute to a reevaluation of their food properties. Their anthocyanin, flavonoid, total phenol, and tannin contents, as well as their antioxidant activity and proximate and mineral composition, were quantified. Red guaje seeds outperformed green guaje ones in N, Mg, Mn, P and Zn contents; by contrast, green guaje seeds had higher Na and Fe levels. Crude fiber content was 10.55 and 10.07 % in red and green guaje, respectively, while protein content was 33.12 % and 31.7 %, respectively. The high content of phenolic compounds was greater in the fresh red guaje seeds (1,088.70 mg gallic acid equivalents [GAE]·100 g-1 FW) than in the green ones (969.09 mg GAE·100 g-1 FW), but the latter had a greater amount of tannins. The high free radical scavenging activity (97.22 to 98.11 %) obtained by the ABTS (2.2 ‘-azino-bis (3-ethylbenzthiazoline)-6-sulfonic acid) method may be associated with the content of phenolic compounds. In conclusion, guaje seeds could be considered as a functional food, but mainly the red guaje ones due to their nutritional quality and higher antioxidant activity.

In the hydroponic growing systems of the Bogota plateau, excess amounts of ions have been found in the leachate. The aim of the study was to determine the Ca, Mg and S contents in the substrate, leachate and tissue of the entire plant of the standard carnation cv. Delphi, with three leachate recirculation percentages and in different phenological development stages. A randomized complete block experimental design in split plots with nine treatments and three replications was used. The calcium concentration in the leachate on the basis of recirculation was significantly higher without recirculating the leachate, whereas, on the basis of the substrates, it tended to be higher in the substrate with a lower percentage of burned rice husk (BRH). For magnesium, the concentration in the leachate increased with crop development, regardless of the factors, and was significantly greater as the recirculation percentage increased. The calcium and magnesium contents were significantly lower in the substrate with higher BRH content. The sulfate concentration in the leachate increased as the recirculation percentage increased, and the highest concentrations occurred under the influence of the substrate with higher coconut fiber (CF) content. In closed systems the magnesium and sulfur concentrations in the fertigation formulas must be adjusted. Furthermore, when CF percentages are maintained in the substrate, it is necessary to consider the retention of the calcium and magnesium ions.

The aim of this study was to evaluate the refrigeration effect on postharvest quality of basil ‘Nufar’. Basil previously packaged in plastic film, was stored at 5, 10 and 20 °C, for 18 days. The variables color (L, C, °h), total soluble solids, titratable acidity, weight loss, respiration rate, ethylene production, total chlorophyll, total carotenoids and vitamin C were evaluated, every two days, during the storage period. Visual appearance, turgor, rottenness and aroma of basil were evaluated using a hedonic scale. Refrigeration treatments retained the color until 12 days of storage (DOS). Sugar content decreased at 14 and 10 DOS, respectively, at 5 and 10 °C. Titratable acidity and weight loss were low and respiratory rate increased, ethylene production was low until 12 DOS at 5 °C; moreover it preserved the highest content of chlorophyll and carotenoids, although vitamin C was retained only until 4 DOS. Visual appearance and turgor were very good until 10 and 12 DOS, respectively; rottenness was greater than 10 % after 10 DOS, under refrigeration. The aroma was perceptible until 14 DOS. Storage at 5 and 10 °C, extended the postharvest quality of basil ‘Nufar’ during 10 and 14 DOS respectively, while at 20 °C, basil lasted only 4 DOS.

This study was conducted from November 2012 to May 2013 to evaluate the effect of inoculating C. canephora with Rhizophagus intraradices and / or Azospirillum brasilense in two substrates in nursery on some morphological and physiological yield components and to determine the amount of phosphorus in plant tissue and quantify mycorrhizal colonization. Soil used was mollic Andosol and two prepared substrates: one was soil and river sand and the other was soil plus 30% coffee pulp (1:1 v / v) in five-kg capacity plastic bags. Treatments were the control, Rhizophagus intraradices, Azospirillum brasilense and a combination of the two on each substrate, giving a total of eight treatments in a split plot in randomized block design with five replications. Samples were taken every 28 days to assess morphological and physiological variables and mycorrhizal colonization and phosphorus content during 140 days after transplant (dat). The results show that inoculation of C. canephora in nursery with either of the microorganisms individually favored growth and dry matter accumulation in morphological and physiological yield components relative to the control. A. brasilense promoted greater biomass accumulation during the evaluation and R. intraradices at the end of the study. R. intraradices increased phosphorus content in the tissue of plants, and higher mycorrhizal colonization was found in the first third of the root when inoculated with R. intraradices.

Production of tomato seedlings in trays has increased in recent years because protecting the root system in a ball reduces transplant shock, resulting in a higher plant survival rate and thus avoiding the need to replant. Greater root development favors establishment in the field because it promotes water and nutrient uptake. Since root production can be promoted by auxin action, the aim of this study was to evaluate the effect of an auxin-based bioregulator on the growth of tomato seedlings in trays. The trial was conducted in a commercial nursery in San Juan, Argentina. The AC 55 tomato cultivar was used. Trays with 126 cells, 36 cm3 per cell, were used. The bioregulator was a commercial formulation containing 0.12 % indole butyric acid and 0.004 % forchlorfenuron. Four concentrations of the product (1, 3, 5 and 7 ml·liter-1) and a control were tested in a completely randomized design with 5 treatments and 4 replicates. Samples were taken at 26, 33, 40 and 47 days after sowing. The variables measured were root dry weight (RDW), aerial dry weight (ADW), stem length (SL), number of leaves larger than 1 cm (NL) and third leaf length (LL). Higher doses increased RDW by 36-39 % compared to the control. The regression between root dry weight and applied dose indicates there could be a response to higher doses. No effect on growth in the aerial part of the plant was observed.

Papaya is a major fruit export for Mexico; however, the international market is increasingly demanding bio quality, representing a significant production challenge due to the need for bio-ecological and sustainable technologies. Arbuscular mycorrhizal fungi (AMF) can contribute significantly to plant nutrition, particularly in phosphorous (P) uptake. The use of AMF in papaya is yielding encouraging results, but there is a need to define certain aspects regarding agronomic management of AMF-based products. The aim of this study was to evaluate the effect of AMF Glomus sp. Zac-2 and P fertilization on the growth of Cera var. papaya during the nursery stage. For this, a 2 x 3 x 4 tri-factorial experiment (AMF inoculation, P source and P dose) was conducted in a completely randomized design. The variables plant height (PH) and stem diameter (SD) were evaluated every 15 days; dry biomass (DB) and spore density (SD) were assessed at the end of the experiment (90 days). From the DB of plants with and without mycorrhizal inoculation, the relative mycorrhizal dependency index (RMDI) was calculated. Data analysis showed significant differences (P ≤ 0.05) between papaya plants with and without AMF for PH, SD and DB, regardless of the P dose and source. At 75 days, growth increases of more than 500 % were recorded in plants with AMF compared to the non-inoculated plants; the RMDI was 99 %. These results suggest that AMF inoculation in papaya during the nursery phase can benefit further growth in the field.