Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Objective: Plant life begins at germination. Stimulating germination with chemical methods can be advantageous. The pregerminative treatment of four promoters was determined in two maize genotypes (G1, G2). Design/methodology/approach: Sixty seeds per Petri dish were used as experimental unit with three repetitions, organized in a completely randomized 2×4 factorial design. Two factors were taken into consideration: A) Genotypes (G1, G2); and B) four pregerminative promoters. The genotypes were Antelope G1 and yellow Antelope G2. Meanwhile, the pregerminative promoters were salicylic acid (‎C7H6O3) (SA), citrulline (C6H13N3O3) (CI), humic substances derived from leonardite (HS), and tap water (TW), in 1000-ppm concentrations. The following variables were evaluated: germination percentage (GP)/days-1, radicle diameter (RD), radicle length (RL), and number of lateral seminal roots (NSR). An analysis of variance and Tukey tests (α £ 0.05) were performed. Results: The germination promoters were highly significant in both genotypes, as well as during the promoter-genotype interaction. G1 and G2 means showed a higher growth and development for humic substances (HS) during germination in the NSR. Study Limitations/Implications: Germination can be inhibited, if the promoters are overweighted. Findings/Conclusions: The best genotype and germination promoter (G2) had a 94% effectiveness and HS at 1000 ppm. CI and SA registered the lowest GP.

Objective: The production of total gas, methane (CH4) and in vitro fermentative variables in diets for sheep with 1 and 2 % sunflower oil were evaluated. Design/Methodology/Approach: Serological vials with 0.5 g of treatment and 50 ml of culture medium were incubated at 39 °C for 24, 48 and 72 h. The production of total gas, CH4, and degradation of dry matter (DEGDM), neutral detergent fiber (DEGNDF), acid (DEGADF), production of volatile fatty acids (VFA) and ammoniacal nitrogen (N-NH3) were estimated. . The experimental design was completely randomized. Results: Total gas production at 48 and 72 h increased (p < 0.05) and at 24 h decreased (p < 0.05) as the oil increased. CH4 production at 24 and 48 h did not present differences (p > 0.05); a linear decrease (p < 0.05) was quantified at 72 h. DEGDM increased (p < 0.05) at 24 and 48 h and decreased (p < 0.05) at 72 h. DEGNDF and DEGADF increased (p < 0.05) at 48 h. Butyric acid content and N-NH3 decreased (p < 0.05) at 48 h. Study Limitation/Implications: An inclusion greater than 2 % of sunflower oil in the diet can reduce the degradability of the food and the microbial protein. Findings/Conclusions: The inclusion of up to 2% of sunflower oil in diets for lambs does not affect the degradation of fibers and is an alternative to reduce the methane emitted into the environment.

Objective: To estimate the percentage of Leucaena in the diet of heifers fed with Taiwan grass, in order to maximize the efficiency of the ruminal supply of microbial Nitrogen (ERSMN). Design/Methodology/Approach: Five heifers were randomly selected for each of the five treatments (0, 20, 40, 60, and 80% supplementation with Leucaena), according to a 5×5 Latin square experimental design. We determined the ruminal supply of microbial nitrogen (RSMN), ERSMN, and the urea-N by measuring N and purine derivatives in urine. Subsequently, we predicted the duodenal RSMN, the rumen nitrogen balance (RNB), and the urea cost with the Large Ruminant Nutrition System (LRNS v. 1.0.33) model. Results: The inclusion of Leucaena improved (P≤0.05) the RSMN. The ERSMN estimated by purine derivatives had a quadratic response (P≤0.05) at the inclusion level of Leucaena in the diet. The RNB, the cost of urea, and the urea-N increased (P≤0.05) with a higher inclusion percentage of Leucaena. The maximum ERSMN and N balance were obtained with 20% Leucaena in the ration. Study Limitations/Implications: The expression of the nitrogen utilization potential of Leucaena for microbial protein synthesis in this study was likely restricted by the limited availability of non-fiber carbohydrates (NFC). Further studies must be conducted to determine the most affordable source of NFC to match Leucaena nitrogen utilization in the rumen. Findings/Conclusions: Leucaena could be used as an efficient protein source for heifers at a 20% inclusion in their diet.

Objectives: To evaluate the production of juice and sugar, the physicochemical parameters of the juice during extraction and quantify the differences between genotypes. Design/Methodology/Approach: An experiment under irrigation was established with 10 genotypes of sweet sorghum in southern Sonora, México, during the autumn-winter cycle, under a randomized block complete design with four replicates. The sowing dates were 03/15/2015 and 02/20/2016. The variables were: days to flowering (DF), weight of fresh biomass (T ha-1): whole plant (WTo), stem (WSt), leaf (WLf), and panicle (WP). After extraction, juice weight (WJ), bagasse weight (WBz), juice volume (JV), and extraction efficiency (EFx:WJ/WSt) were determined. The juice was sieved to remove impurities. There were determinate at the time of extraction: pH, temperature (°C) and degrees Brix. Results: The sources of variation had a significant effect on the production of biomass, juice, and sugar. The year contributed to explain 53 % of the variation, the genotype explained 36 %, while the interaction (GxA) only 5 %. On average, the production of fresh stem biomass was 38 t ha-1, with 28 % efficiency in juice extraction. The SWS686 and SWS694 genotypes exceeded the average in juice production and the control (M81E). Juice production in 2016 was higher (31 %) than in 2015. In average, the juice values were of 32 °C, 12.9 oBrix and pH 3.8. Study/Limitations/Implications: The decrease in the content of soluble solids and spontaneous fermentation during the conservation of the juice under room temperature can limit the use of sweet sorghum in areas where temperatures are >30 °C in post-harvest stage. Findings/Conclusions:There was an effect of the environment and genotype on the production and quality of sweet sorghum juice. It is necessary to make a complete analysis of the life cycle that indicates the challenges and opportunities to improve the efficiency of the processes to obtain sweet sorghum juice

a) Objective. The objective was to evaluate the forage production of maize, maize + sunflower and its preference for sheep as silage. b) Design/methodology/approach. The design in the field was in completely randomized blocks with three replications and in the laboratory in a completely randomized design (Tukey α = 0.05). Sowing was in spring - summer 2020 under rainfed conditions. The treatments were: 100 % corn, 90 % corn + 10 % sunflower, 80 % corn + 20 % sunflower. Forage production was evaluated at 126 days of sowing, it was ensiled and the quality through bromatological analysis. For silage preference, 10 pregnant Hampshire × Suffolk ewes were used with 44.8 kg of live weight along 20 days. c) Results. The 80 % maize + 20% sunflower combination showed higher green forage yield (P<0.001; 28 t ha-1), higher percentage of soluble protein (P<0.01) and higher percentage of lignin (P<0.001; 4.6 %). The sheep preferred the silage with 100 % corn, since it had a lower percentage of non-fibrous carbohydrates (22.2 %), lower acid detergent fiber (35.3 %) and lower neutral detergent fiber (59.4 %). d) Limitations/implications. Sunflower should be established on soils with low numbers of broadleaf plant seeds, because chemical control cannot be applied. e) Findings/conclusions. A greater amount of forage was produced per surface unit whit 80 % corn + 20 % sunflower. The 100 % maize silage was preferred by sheep due to lower percentage of lignin, and higher in vitro digestibility of neutral detergent fiber.

Objective: To characterize the egg from three hen genotypes: Mexican Creole (MC), Hy-Line Brown (HLB) and Rhode Island Red (RIR). Design/Methodology/Approach: Three groups of each genotype were formed using 75 hens (30 MC, 30 HLB and 15 RIR), 20 weeks old. Daily, for 84 days, two eggs were chosen randomly from each group to determine: weight (w, g), length (L, cm), width (Wth, cm), shape index (SI), volume (VOL, cm³), area (AR, cm²), shell color (SCo), yolk color (YCo), white weight (WW, g), yolk weight (YW, g), shell weight (SW, g), white proportion (WProp), yolk proportion (YProp), and shell proportion (SProp). The means were compared with Tukey’s test, P˂0.05, using the SAS software. Results: The genotype HLB was superior (P<0.05) in W, Wth, SI, VOL, AR, SCo, WW, and WProp (61.220 g, 4.400 cm, 0.801, 55.890 cm³, 71.723 cm², 6.834, 38.030 g and 0.621, respectively). There were no differences between genotypes (P>0.05) in L (5.383 to 5.490 cm). The MC hens were superior (P<0.05) in YCo, YW and SProp (6.738, 15.923 g and 0.132, respectively). The SW differed (P<0.05) between genotypes: HLB (7.550 g), MC (6.661 g) and RIR (6.205 g). MC and RIR had higher (P<0.05) YProp (0.314 and 0.304, respectively) than HLB (0.250). Study Limitation/Implications: The study contemplated only one part of the production period of the birds. Findings/Conclusions: Each genotype produced egg with particular physical characteristics, with Creole hens standing out due to their high values of yolk color and proportions of yolk and shell.

Objective: To determine the cellulose, hemicellulose and lignin production of six Cenchrus purpureus cultivars with or without fertilization, harvested every 21 days for 168 days. Design/Methodology/Approach; The cultivars evaluated were: CT-115, Elefante, King grass, Maralfalfa, Roxo and Taiwan, with and without fertilization. The experimental design was a randomized complete block with a split plot arrangement with four replications. The fertilization dose was 141-43-20 of NPK. Forage was harvested every 21 days for six months in the rainy season. The samples were determined: Dry Matter (DM), Ash, FDN, FAD, Hemicellulose, Cellulose and Lignin. A nonlinear regression analysis was performed. Biomass production was determined with the estimated values ​​and the percentage of each component. The goodness-of-fit indicators were: R2, the coefficient of determination (R) and the model selection criterion (MSC). The parameters and coefficients of goodness of fit were analyzed in ANOVA with the SAS software in the GLM procedure. Means with Tukey's test. Results: The Maralfalfa cultivar presented higher cellulose production (3786 kg ha-1) and similar (p>0.05) to the Elefante and Taiwan cultivars with values ​​of 3451 and 3329 kg ha-1 and different (p<0.05) to CT- 115 and King grass with more than one ton ha-1 of cellulose. Study Limitations/Implications: Cellulose production was increased by the effect of fertilization. findings/conclusions. Findings/Conclusions: The fertilized Maralfalfa, Elefante and Taiwan cultivars produced more than 4000, 3000 and 1000 kg ha-1 of Cellulose, hemicellulose and lignin, respectively.

Objective: To evaluate the aerial biomass yield and nutritional value of Moringa oleifera at densities of 50,000 (D1), 100,000 (D2) and 200,000 (D3) plants ha-1. Design/methodology/approach: The experiment was established under a random complete block design arranged in divided plots and three repetitions and from 155 days after planting 5 cuts were made every 28 days. The variables evaluated were yield (kg ha-1) of total dry matter (TDM), sheet (sDM) and contents (g kg-1) of crude protein (CP), neutral detergent fiber (NDF) and acid (ADF). Results: An interaction between densities and cuts was observed. In TDM performance, in cuts 1 and 2, D1 outperformed D2 and D3, by 71 % and 83 %, respectively; however, D3 had the highest TDM yield (P<0.05) in cuts 3 and 4, 47 % higher than D2 and D1 and D2 by 46 % and 76 %, respectively. The highest yield of sDM was presented in D1, in cuts 1 and 2 (561 and 852 kg ha-1, respectively); while D3 showed the highest values in cuts 3 and 4, (901 and 1054 kg ha-1, respectively). When increasing from D1 to D2 there was a decrease (P<0.05) in the CP content of 11 % (222 vs. 198 g kg-1). Regarding the values of NDF and ADF, no differences (P>0.05) were found between the densities evaluated. Limitations/implications: The density of plants in Moringa oleifera determine the yield potential and nutritional value of the forage. Findings/conclusions: Moringa oleifera established in semi-arid conditions at a density of 50,000 ha-1 plants and with cutting intervals of 28 days, presented the best productive behavior in terms of yield and protein concentration.

Objective: Due to the importance of beans in human consumption, the vegetative development and seed yield of Black Veracruz beans were evaluated using a nutrient solution with different magnetization times in combination with different pH. Design/methodology/approach: The experimental design used was completely randomized with a 4 x 6 factorial arrangement with three replications. 24 treatments of the combination of four magnetization times and six degrees of acidity of the nutrient solution were evaluated. The variables evaluated were vegetative development and yield components. The results were subjected to an analysis of variance and media separations were performed using Tukey's test (α £ 0.05). Results: The magnetization and the degree of acidity of the nutrient solution significantly influenced the variables. The most outstanding treatments were 2 and 24 hours of magnetization in combination with pH values ​​of 4 and 5, for most of the variables of vegetative development and evaluated yield components. The 2 magnetization treatments together with pH values ​​of 4 and 5 increased height, biomass hours, days to flowering, number of pods, harvest index and seed yield. Study Limitations/Implications: Care should be taken that magnetic field exposure at high intensities may produce adverse effects on growth and development. Findings/conclusions: It is concluded that an appropriate combination of magnetization time and degree of acidity of the nutrient solution improves vegetative development and yield.

Objective: To evaluate the vegetative, reproductive, production, and forage quality characteristics of three Buffel grass varieties from northern Tamaulipas. Design/Methodology/Approach: A pot trial was established under open field conditions, at CERIB-CIRNE-INIFAP in Río Bravo, Tamaulipas, on 04/15/2016 and 03/10/2017; the experiment was carried out with a completely randomized design, with 30 replications per material. The morphological, reproductive, production, and chemical composition characteristics of the Milenio, Regio, and Titán Buffel grass varieties forage were evaluated. Results: The year accounted for 62.3% of the variation in the stem and leaf characteristics. The genotype contributed 35.4% and G*Y interaction, less than 2%. Regarding the reproductive variables, the genotype accounted for 62% of the results, the G*Y interaction, 25%, and the year, 13%. The genotype and the year accounted for 44% and 47% of the variance in forage production and quality, respectively. The G*Y interaction had no statistical effect. Limitations/Implications: The evaluation was carried out under pot conditions, which implies that the roots of the plants have limited growth and that the expression of some of the characteristics of the material may be restricted. Findings/Conclusions: The major differences between the three varieties were found in their morphological characteristics: duration of the flowering stage, reproductive stems proportion, panicle length, exertion of the panicle from the main stem, number of florets per panicle, and seed weight.