Abstract In order to scientifically evaluate the germplasm resources of Momordica charantia  in southern China, the diversity, correlation and cluster analysis were carried out on the main botanical characters of 56 Momordica charantia  varieties, such as melon length, melon transverse diameter, single melon weight, internode length, stem diameter, leaf length and leaf width. The results showed that the variation coefficients of 7 agronomic characters of 56 Momordica charantia  varieties ranged from 8.81% to 19.44%, the average variation coefficient was 14.21%, the maximum variation coefficient of single melon weight was 19.44%, and the minimum variation coefficient of melon cross diameter was 8.81%. The correlation analysis showed that there were correlations among the agronomic traits. The positive correlation coefficient between leaf length and leaf width was up to 0.978, and the negative correlation coefficient between single melon weight and internode length was up to 0.451. The 56 varieties were divided into 3 groups by cluster analysis, of which 92.86% of the materials were concentrated in the first and second groups, and there were only 4 materials in the third group. The results can provide a reference for the cultivation, utilization and genetic improvement of Momordica charantia  resources in southern China.

Abstract The effects of different storage temperatures (2, 4 and 8 ℃ ) and their corresponding optimal heat treatment conditions on the quality, physiological and biochemical indexes of Cucumber Fruits during storage were studied by using the quadratic regression orthogonal rotation combination design. The effects of different storage temperatures (2, 4 and 8 ℃ ) and their corresponding optimal heat treatment conditions on the chilling injury, hardness, weightlessness rate, polyphenol oxidase (PPO), catalase (CAT), peroxidase (POD), H 2 O 2 , super oxygen anion free radical (O 2- ), ASA and GSH were determined. The results showed that heat treatment could inhibit chilling injury, while heat treatment combined with 4 ℃  low temperature storage could effectively inhibit the dec line of fruit hardness and weight loss rate, delay the increase of peroxidase (POD) and polyphenol oxidase (PPO) activities, inhibit the increase of H 2 O 2  and superoxide anion free radical O 2-  and significantly inhibit the browning of cucumber, delay the de cline of ascorbic acid and maintain the content of GSH, it was beneficial to adjust the balance of active oxygen system. The results showed that under the storage condition of 4 ℃ , the hot water treatment condition of cucumber was 39.4 ℃  and 24.3 min, whic h could delay the senescence of cucumber fruit and better maintain the quality of cucumber fruit.

Abstract Introduction:  Growth, yield and quality of okra ( Abelmoschus esculentus  (L.) Moench) are related to fertilizer application, being nitrogen (N) the most outstanding, due to its direct relationship with photosynthesis and vegetative growth of the plant. Objective:  The objective was to evaluate the agronomic and productivity characteristics of okra as a function of N dose. Materials and methods:  The study was conducted at the experimental area of Campus Gurupi, the Universidad Federal de Tocantins (UFT), Brazil, in two planting periods (autumn/winter and spring/summer). The experimental design used was randomized block design (RBD) with six treatments (50, 100, 150, 150, 200 and 250 kg N ha -1 ) and four replications. Urea was used as a source of N. The characteristics evaluated were: productivity, average fruit mass, height and plant chlorophyll index. Results:  Productivity and plant height were superior in the fall/winter crop. Mean fruit mass and chlorophyll index were not influenced by planting time. For productivity, a linear response was obtained with increasing dose up to the limit of the N dose used (250 kg ha -1 ), with a mean value higher than 14 t of fruit. Mean mass and plant height responded linearly to increasing N dose. Nitrogen affected the chlorophyll index, with maximum values of 45.96 and 47.19, observed in the two evaluation periods. Conclusion:  Planting time and N content in the soil interacted with plant height, being favorable in the period without precipitation. N influenced all the characteristics, demonstrating the importance of nitrogen fertilization in the development of okra plants.

Abstract The xanthorrhiza  species of the genus Arracacia belongs to the Apiaceae family and is known for its ability to generate tuberous reservoir roots that are harvested annually and marketed fresh in South American countries such as Colombia, Brazil, Venezuela, Peru, Bolivia and Ecuador. In Colombia, arracacha is planted  mainly in 15 departments and the regional cultivars are differentiated by the color of the leaves, petiole and tuberous root, the best known being amarilla común  or paliverde , yema de huevo , and cartagenera . There are studies that have characterized regional materials by applying a limited number of descriptors, but they do not allow knowing the morphology and phenotypic differentiation of each one; therefore, their definition and characterization constitute a support in breeding programs that allow the efficient use of the genetic potential and increase the knowledge about the diversity of cultivars. Phenotypic characterization and description of three cultivars was performed during two production cycles (2016 and 2018) in two phases (vegetative and productive) applying 74 morphological variables (42 qualitative and 32 quantitative) organized in seven groups of variables: plant, leaf, leaflet, petiole, propagule, stock and tuberous root. A factorial analysis for mixed data (FAM D ) was performed, which incorporated a multivariate analysis with all variables and identified 11 discriminant variables, 8 qualitative and 3 quantitative, which can be used in processes of characterization of arracacha materials. A morphological description of each cultivar was made, which means that this is the first complete characterization study of regional arracacha materials in Colombia.

Abstract Introduction :   The selection of genotypes with determinate growth habit in tomato should contemplate adequate selection criteria to increase the efficiency of the breeding program. Objective: The objective of this work was to estimate selection criteria for “chonto” type  tomato lines with determined growth habit. Materials and methods: This work was carried out at the Universidad Nacional de Colombia (Palmira Campus), in 2016, with seven lines with determinate growth habit and a control with indeterminate growth. Heritability in a broad sense (h 2  g), coefficient of environmental variation, coefficient of genetic variation, selection efficiency and genetic gain were determined in parameters of morphological, phonological, fruit quality, fruit shape and production, using the RELM/BLUP procedure of the SELEGEN software. Results: There were three ranges of h 2  g, the first with values of h 2  g greater than 0.76, the second between 0.53 and 0.38, and the third with a value less than 0.38. The highest values of h 2  g were for final plant height with 0.92, plant height at harvest with 0.88, yield per plant with 0.83, days to flowering with 0.83, number of fruits per plant with 0.82, and days to harvest with 0.82. For genetic gain it was found that the control had the highest values for final plant height, plant height at harvest, internode length, days to harvest, harvest duration, soluble solids content, number of fruits per plant, fruit weight and yield per plant; however, in some parameters such as height and phenology for selection by determined growth habit, the lowest values were better. Conclusion: There was evidence of genetic parameters that could be considered as selection criteria for “chonto” type tomato lines with determinate growth habit.

Abstract The characteristics of agricultural products are influenced by the ecosystem, from the perspective of biotic and abiotic factors, which produce in the plant physiological responses and in turn in the fruit unique physicochemical properties, which are the basis for designations of origin and strategies to add value to the product in the current market. In the present work, ten cocoa materials ( Theobroma cacao  L.) were selected for their outstanding productivity (FSV41, FLE3, FEAR5, FSA12, FEC2, SCC23, SCC80, SCC55, ICS95 and CCN51), which were established in the departments of Santander (931 m a.s.l.), Huila (931 m a.s.l.), Huila (931 m a.s.l.), Huila (931 m a.s.l.), Huila (931 m a.s.l.), Huila (931 m a.s.l.) and Huila (931 m a.s.l.). These were established in the departments of Santander (931 m a.s.l.), Huila (885 m a.s.l.) and Arauca (204 m a.s.l.), the main cocoa-producing areas in Colombia. For the evaluation of the physical characteristics of the collected materials, 21 quantitative descriptors were used to determine the physical variability of the fruit according to clone and place of collection. The data collected were analyzed by means of Pearson’s correlation matrix and principal component analysis, it was possible to identify those descriptors that contribute most to the variability among materials (ear index, diameter length ratio, seed weight and diameter, and fruit weight and length). In addition, it was possible to verify the effect of the place of harvest on the physical characteristics of the materials, high-lighting the importance of the adaptation study prior to the planting of the cocoa material, with the objective of guaranteeing a premium, productive and quality cocoa crop for the industry, which is competitive in the market.

Abstract With the purpose of knowing the phytosocilogy of weeds associated to a carrot crop ( Daucus carota L.) under conditions of the municipalities of Ventaquemada and Jenesano-Boyacá, one lot per municipality destined to carrot cultivation was selected and a W-shaped layout was made covering an area of 500 m 2 . Relative density, relative frequency, relative dominance and the importance value index (IVI) were calculated, as well as the Alpha and Beta diversity indices for the sampled areas. A total of 6 families and 11 species were counted, of which 63.64% were represented by annual plants and 36.36% by perennial plants. The class Liliopsida (Monocotyledon) was represented by the Poaceae family. The Magnoliopsida class (Dicotyledon) was represented by the following families: Asteraceae, Brassicaceae, Boraginaceae, Leguminosaceae, Polygonaceae, the last one being the one with the highest number of species. The species R. crispus and P. nepalense were the ones with the highest values of Importance Value Index (IVI) with 0.953 and 0.959, respectively. According to the Shannon-Wiener diversity and Simpson’s dominance indices, the evaluated areas presented a low species diversity and a high probability of dominant species. The results obtained can serve as a basis and tool for carrot growers in the evaluated areas to define management plans for the associated weeds and thus optimize yields in this crop.

Abstract Different color-promoting treatments were tested on table grape cv. “Flame Seedlees” to evaluate changes on flavonoids such as anthocyanins and the residual ethylene produced. Treatments were spray-applied at the onset of veraison. The control was Ethrel at 250 ppm (ETH), Salicylic Acid at 100 ppm (AS), Melatonin at 25 ppm (MEL) and 1:1 mixtures of ETH+AS, ETH+MEL and AS+MEL. The trials were conducted in triplicate after harvest, measuring Total Soluble Solids (% TSS), total acidity (% tartaric acid), pH, residual ethylene (ppm) and anthocyanin content (mg∙cm -2 ). It was found that treatments ETH, AS, MEL and ETH+AS reached 16% TSS, standing out with lower values ETH +MEL (14.27%) and AS+MEL (15.17%) (p ≤ 0.05). ETH reached 0.83 ppm of residual ethylene, while a sum effect was appreciated in ETH+AS (0.5 ppm) and ETH+MEL (0.35 ppm), but not beneficial as it did not reflect quality characteristics. Only differences (p ≤ 0.05) in anthocyanin content were recorded between ETH (0.019 mg∙cm -2 ) and AS+MEL (0.003 mg∙cm -2 ). The subjective color of the grape bunches in the field made it possible to relate it to the objective results of the analyses performed. This research provides commercially important information on the substitution of Ethrel by natural compounds such as AS and MEL, as they show similar effects on the quality of “Flame Seedless” table grapes. In addition, these compounds do not have an ethylene residual greater than 0.2 mg/kg.

Abstract Open pitaya ( Stenocereus thurberi ) flowers were marked at 10, 20, 30 and 40 days after floration (DAF). When fruit were formed, they were collected from each of the dates with the objective of evaluating physical, physiological and quality changes before and after harvest. In fruits with different DAF, the analyses of fruit size (diameter and length), weight, density, firmness, color in pulp and peel (L*, a* and b*), respiration rate (CO 2 ) and ethylene production were carried out. In the case of ripe and overrip e fruit, in addition to the variables mentioned above, pH, percentage of total soluble solids TSS and total acidity (% citric acid equivalents) were evaluated. Fruit with 40 DAF were stored for up to 14 days at 25  ℃  and 80% RH to evaluate daily changes in respiration rate and ethylene production. It was found that during development the fruit tended to grow more in length than in diameter. In color, the best indicators of changes during fruit development were the parameters L* and b* for peel and for flesh L* and a*. For firmness in pitaya fruits, no significant differences were found with the methodology used. Changes in ethylene production and respiration rate during storage and development showed the usual behavior of climacteric fruits. Pitaya fruits with 40 FDD presented quality characteristics similar to those accepted by the consumer for this type of fruit. It is concluded that it is possible to evaluate the different stages of development in DDF of pitaya fruit based on the changes of the color space variables L*, a* and b*, in addition to the fact that the fruit follows the classical climacteric behavior.