Brassia verrucosa Bateman ex- Lindl was propagated in vitro to determinate the best conditions of culture for seed germination and see¬dling development, to facilitate the design of an initial strategy for its conservation and rescue. Seeds were germinated in Murashige and Skoog (MS) medium, and seedling were grown in MS (T1), MS supplemented with organic extracts, coconut water, peptone and active charcoal (T2) medium and MS supplemented with organics extracts, coconut water, peptone and gibberellic acid (T3). Germination was 56.70 %, initiating six days after sowing. The variables number of buds, leaf width and root length were affected by the treatments, but not leaf length, root number or seedling height. The Tukey analysis showed significant differences for all the variables with the exception of leaf width and root length. T2 showed the highest values for the variables number of buds, leaf length, root number and seedling height. Germination and development of the plants are the beginning of a strategy for conservation and rescue of the species.

Glutamic acid is an amino acid that is involved in several plant metabolic processes. This study was conducted to determine whether the foliar application of glutamic acid produces better development of the tomato plant and increases fruit production. The experiment was conducted under greenhouse and hydroponic conditions. The variables which produced positive responses to the application of glutamic acid were chlorophyll b content, fruit fresh weight, fruit dry weight and activity of the enzyme glutamine synthetase.

The application of polyvinyl acetate (PVA) was assessed as a potential protective edible coating in round-type tomato fruit (Lycopersicum esculentum Mill, cv. Gabriela) at the green stage of maturity. Coated and uncoated fruits were stored at ambient (20 °C, 40 % relative humidity, RH) and controlled (21 °C, 60 % RH) conditions during seven and 14 days and the effects on color, luminosity, weight loss, firmness, °Brix, vitamin C and respiration rate were studied. The polymeric coating did not significantly affect brightness, weight loss, and RR; however, environmental conditions at which the fruits were maintained had significant effects. Despite the statistically non-significant effects, our results showed that PVA coating was associated with slight protection of the fruit compared to uncoated fruits. This outcome is encouraging but suggests that more research is needed to consider these facts and control others that might be important in fruit ripening, such as molecular weight of the PVA, uniformity and thickness of PVA application.

In order to characterize morphologically 32 accessions of guajillo chili pepper (Capsicum annuum L.) from the states of Zacatecas and Durango, Mexico, an experiment was established in Chapingo, Mexico, under an experimental design of randomized complete block with three replications. The experimental unit consisted of one row 4 m long and 90 cm wide, with distance of 40 cm between plants. The crop was managed in padded black with silver colored plastic and a fertigation system. Quantitative and qualitative characters were evaluated based on the descriptor guide for Capsicum of IPGRI and analyzed by principal components (PC) and hierarchical clusters (HC). The first three PC explained 58 % of the total quantitative variation among the accessions; the largest contribution to this variation was the charac¬teristics associated with leaf morphology and flower structure (length and width of mature leaf, petiole length, corolla length and corolla width), fruiting days and number of fruits per plant, in addition to phenological variables. Through the HC, five groups were formed in the dendrogram of quantitative variables. With regard to qualitative variables, three PC explained 76 % of the variation between accessions; branch density and leaf, tillering, shape of the corolla, fruit color and termination of the fruit tip contributed more to explaining the variation detected among accessions; the HC formed 8 groups. The results indicate that sufficient morphological diversity exists in Guajillo chilli to be useful in starting a breeding program.

The aim of this research was to characterize the physical and biochemical changes during growth, development and postharvest of rambutan fruits in outstanding selections from Tuxtla Chico, Chiapas (RI-148, RI-115 and RI-104). After anthesis, chemical and physical parameters were evaluated in fruits; at harvest quality characteristics were evaluated at 22 ± 1 ºC and 65 % RH. The results showed a sigmoidal pattern of growth. During development, fruits of the selections RI-148 and RI-115 had a fresh weight of 39.27 and 35.42 g and an aril content at harvest of 44.28 and 40.90 %, respectively, while those of the RI-104 were smaller (18.51 g) but with thicker pericarp, showing less susceptibility to oxidation. The number and length of spines does not seem to be the main factor related to fruit browning.

The objectives of this investigation were to characterize the quality components of the chickpea fruit, to describe the anatomy of the pod, and to study postharvest technology for increasing the shelf life of the fruits. Green chickpeas cv. ‘Blanco Sinaloa’ were harvested; proxi¬mate analysis, minerals, pH, acidity and total soluble solids were separately analyzed in both pods and seeds. Histological evaluations were done on pods at 0, 6 and 12 days. Four lots of fruits were treated, each with 1) 0.5 μl∙L-1 and 2) 1.0 μl∙L-1 of 1-methylcyclopropene (1-MCP), 3) sprayed water at 65 °C, and 4) control. Samples were stored for 12 days at 10 °C using PET containers. Evaluations of weight loss, color, and respiration rate were done every 3 days. Chickpea seed and pod showed a good nutritional profile based on the protein, fiber, calcium, potassium, and iron content. Also, in both tissues pH = 6.0 was observed. The cell anatomy of the pod showed a well struc¬tured cuticle at day 0, which remained compacted through the storage; also, a change in cells from the parenchyma towards sclerenchyma was observed, indicating cell aging. The 1-MCP treatments significantly decreased weight loss and metabolic activity of chickpeas as compared to control samples; however, none of the treatments showed a significant effect on green color retention.

Tissue samples of papayo plants with mosaic and yellow crinkle symptoms collected from Michoacan and Veracruz were examined to detect phytoplasma with polymerase chain reaction (PCR), using primers derived from ribosomal RNA 16S and 23S from phytoplasmas. The sequences of the amplified PCR products were homologous to polynucleotide sequences belonging to phytoplasmas. The restriction patterns obtained through digestion of the amplified DNA evidenced the presence of two phytoplasmas in plants showing mosaic and yellow crinkle symptoms. One of them matched the aster yellow group 1 16S subgroup C. The patterns of the other phytoplasmas did not match any of the restriction patterns up to now reported. Tissue from diseased plants reacted positively to the fluororochrome-4,6-dyamidino-2- phenylindol (DAPI) which stains DNA, therefore suggesting the presence of nucleic acids from biotic agents inside the phloem.

The objectives of this work were to characterize strawberry growers in Zamora, Michoacán, Mexico, and to identify factors limiting produc¬tion with the methodology of innovation networks. The state of Michoacán is the largest strawberry producer in Mexico, but production is extensive and disorganized. The productive system network of strawberry has a large number of nodes, but dispersion is high. This fact is reflected in the scarce number of links (265), a low density and an elevated standard deviation (12.47 %). The centralization index is 18.36 %, in part because decision-making and access to system information in the web are concentrated in only two actors; one of them is a final buyer and the other is a local lender. The strawberry agribusinessmen from Michoacán interviewed had a mean yield of 24.44 t•ha-1. Their per hectare income was $ 9,208 USCy, but with a cost of production of $11,867 USCy and an index of innovation adoption of 55.56 %. The adoption of organizational innovations is limited. All these factors originate low macro competitiveness. It is necessary to enhance innovation to increase the competitiveness.

Transplanting in intensive horticultural systems, such as chili, has permitted better planning of crops with preformed structures and growth uniformity, efficient use of seed, and early production. The objective of this study was to determine the effect of plantlet age at transplant on phenology, growth and yield of apaxtleco chili (Capsicum annuum L.) from Apaxtla, Guerrero, Mexico, grown in a greenhouse. Treatments were three ages at transplant: 15, 30 and 45 days after emergence (T1, T2 and T3, respectively) distributed in a randomized block design with eight replications. Plant density was 26 plants•m-2. The results indicate that with T3 a larger number of fruits, leaf area and plant height were obtained. In biomass, plants in T1 accumulated more in the stem (57 %), followed by leaves and fruit (29 and 14 %, respectively). With T3, more biomass was accumulated in the fruit, and consequently, yield was higher (44.3 g•plant-1) 1.15 kg•m-2.

Using mini-tubers for potato seed production under controlled conditions healthy, vigorous and productive plants can be obtained and the number of multiplications in the field can be reduced to achieve greater availability of seeds in the short term. The study was conducted to determine, the effect of sowing immature tuber-seed on the development and yield of potato under greenhouse conditions. Four degrees of tuber-seed maturity were evaluated: 22, 37, 51 and 63 days after tuber initiation (maturity of one, two, three and four, respectively), in Alpha, Atlantic, Mondial and Vivaldi varieties. A complete randomized block design was used and a statistical analysis as series of experiments was done. Duration of the biological cycle in degree days (DD) was longer in plants produced by tuber-seed with the lower degree of maturity (1230 DD). In the Alpha variety DD was1246 because in with tuber-seed maturity degree one, the vegetative stage (165 DD) and reproductive final stage (825 DD) were more prolonged. In addition, the Alpha variety produced more tubers per plant. The total weight of tubers per plant was similar in the tuber-seed with maturity degree one, two and four (249 to 273 g); however, among varieties, Mondial had the highest yield (316 g). The younger the tuber-seed used, the longer the biological cycle and the more the tubers per plant. Also, accumulated biomass of the aboveground part of the plant decreased.