Agro Productividad <p><strong>Agro Productividad</strong> es una publicación mensual del Colegio de Postgraduados en Ciencias Agrícolas. Fue fundada en 2008 con el objetivo de difundir resultados en artículos científicos originales, así como notas científicas, revisiones temáticas, relacionados con la agricultura (cultivos, silvicultura, ganadería, pesca y acuicultura, y agroindustria) y la producción de agroalimentos.</p> <p>También aborda temáticas sobre procesos económicos, sociales y ambientales que impactan la productividad agrícola y el desarrollo rural.</p> <p>Todas las contribuciones recibidas son sometidas a un proceso de arbitraje doble ciego y edición final. La revista se publica en español y en inglés. Se encuentra indexada a diferentes indicadores nacionales e internacionales resaltando <strong>CONACYT </strong>(Competencia Internacional), <strong>Zoological Records, CAB ABSTRACTS, CABI, Periodica, </strong> <strong>Latindex </strong>(Directorio y Catálogo), <strong>Biblat, Master List y Clarivate Analytics, REDIB.<br /></strong></p> <p><strong> </strong></p> es-ES (Dr. Jorge Cadena Iñiguez) (M.C. Valeria Abigail Martínez Sias) sáb, 20 mar 2021 14:15:11 +0000 OJS 60 Perenial ryegrass (Lolium perenne L.) yield as a response to fitoregulators produced in digestates <p><strong>Objective:</strong> To assess the effect on ryegrass (Lolium perenne L.) as a response to<br />phytoregulators produced in digestates obtained from the anaerobic digestion of cow manure, at different initial Ph.<br /><strong>Design / methodology:</strong> Anaerobic cow manure digestions were set up at different<br />initial 5, 6.5, 7.5 and 8.5 pH values and 4, 8 and 20 days of digestion, from these, gibberellic acid (AG 3 ) and indole acetic acid (IAA) were quantified. These<br />digestates were applied to ryegrass grown in containers: on 6 months pastures<br />applying all the digestates and in 45 days pastures digestates at 4 days of digestion. The assessed variables were height, fresh and dry weight and number of. The control was developed on unfertilized soil.</p> <p><strong>Results:</strong> The initial pH of the digestion influenced the production of<br />phytoregulators, being higher at pH 5.5 and 6.5; no IAA production was recorded at<br />basic pH. The application of the digestates had a different effect depending on the<br />pastures age, was greater on the leaf weight variable. In 6 months pastures the increase was between 21 and 24%, in young pastures from 48 to 115% respect to the control. Likewise, there were between 50 and 60% greater number of stems than in the control, applying digestate at 4 days of digestion.<br /><strong>Limitations / Implications:</strong> The study took place on ryegrass, it would be of interest in the area to evaluate it in other crops .<br /><strong>Findings / Conclusions:</strong> The initial manure pH has a higher effect on the digestates properties the those of the time of digestion. Digestates can be a fertilizer for ryegrass, its effect is better in young grasses. The digestate even with 4 days of digestion has a positive effect on ryegrass development.</p> Job J. Castro-Ramos , Rigoberto Castro-Rivera , María M. Solís-Oba, Guadalupe Osorio-Cortes, Angélica Romero-Rodríguez , Ana P. Juárez-Rangel Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Fertility in Cebú × brown Swiss cows treated with prostaglandins, progesterone and eCG <p><strong>Objective:</strong> To evaluate the application of one or two doses of prostaglandin F2?<br />(PGF2?), the application of a progestogen on different days of the estrous cycle and the<br />usage of eCG in the estrus synchronization and fertility of Zebu × Brown Swiss cows.<br /><strong>Design / methodology / approach:</strong> The study was based on three protocols. The first<br />consisted of two treatments: PGI) 26 cows were injected with a single 25 mg dose of<br />PGF2? and 10 cows with two 25 mg doses of PGF2? at a 14-day interval. Protocol 2<br />consisted of two treatments: NG14) 11 cows were implanted with 3 mg of Norgestomet<br />on day 7 of their estrous cycle and NG7) 11 animals received the same dose on day 14.<br />In protocol 3 all cows were implanted with 3 mg of Norgestomet for 9 days, 48 h before<br />removing the implant, 25 mg of PGF2? was applied. Once the implants were removed,<br />they were distributed into two treatments. Norgestomet (n = 11) without eCG and<br />Norgestomet + eCG (500 IU) (n = 11).</p> <p><strong>Results:</strong> The application of PGF2? at two times had no influence (p &amp;gt; 0.05) in the<br />estrous percentages and conception. The NG7 achieved estrous synchronization in 81.8<br />% of the cows, in between 24 and 36 h, compared to 45.4 % of the NG14; however, the<br />conception rate was lower (p ? 0.05). The eCG application synchronized 90.9 % of<br />estrous between 24 and 36 h, compared with 36.4 % of the group with no eCG<br />application.<br /><strong>Study limitations / implications:</strong> Transrectal ultrasounds are required to assess the<br />ovarian structures present at the time of the estrus onset in a synchronization protocol.<br /><strong>Findings / conclusions:</strong> Cows that present corpus luteum do not require more than<br />one injection of PGF2?, the pregnancy percentage increases when Norgestomet is<br />implanted on day 14 of the estrous cycle, in addition the application of eCG increases<br />the synchronization percentage of the heat between 24 to 36 h after the progestogen<br />withdrawal.</p> Joel Ventura - Ríos , Alejandro Lara - Bueno , Pedro Carrillo - López , Perpetuo Álvarez - Vázquez , Francisco A. Cigarroa - Vázquez , Juan A. Encina - Domínguez Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Bibliometric analysis of scientific research on biochar <p><strong>Objective:</strong> To identify the most relevant aspects of global scientific research on biochar<br />in terms of number of articles published, main authors and publishing countries, citation,<br />subjects of scientific journals, funding institutions and general trends.<br /><strong>Design/Methodology/Approach:</strong> A bibliometric study was carried out in the Scopus<br />database. The word &amp;quot;biochar&amp;quot; was used in the search engine. The search was limited to articles and reviews published from 2009 to March 2020. The VOS viewer software was used to identify the main thematic axes and to glimpse the knowledge gaps that exist to date.<br /><strong>Results</strong>: A total of 11,444 documents were identified. The trend of work on biochar is on<br />the rise. China and the United States are the countries with the most publications on<br />biochar. Jefferson Lehman and Stephen Josephs are the most cited authors on the<br />subject. Global research on biochar focuses on the mitigating effect of climate change<br />and the properties that this material has to improve the physicochemical properties of<br />the soil. Research on biochar in Mexico is scarce.</p> <p><strong>Study Limitations/Implications:</strong> Biochar is a new technology that is not fully<br />understood.<br /><strong>Findings/Conclusions:</strong> Interest in biochar as a multifaceted solution to agricultural and<br />environmental problems is growing at a rapid rate both domestically and internationally.</p> Arturo Pérez Vázquez, Luis A. Galindo-Segura, Cesáreo Landeros Sánchez, Fernando Carlos Gómez -Merino Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Structure and operation of the rabbit meat production chain, Texcoco, México <p><strong>Objective:</strong> The objective was to describe and to analyze the situation and interrelations<br />among the of the rabbit meat production chain, in order to identify the main factors that<br />determine competitiveness.<br /><strong>Design / Methodology / Approach:</strong> The methodology used in the research was mixed<br />(qualitative and quantitative). The type of sampling we used was “Snowball”. A survey<br />was applied to 33 rabbit producers and a statistical analysis of the data was performed<br />in SPSS (Statistical Package for the Social Sciences). Later, with the use of Geographic<br />Information Systems, the farms were geo-located with Arcview® version 3.2.<br /><strong>Results:</strong> The results show the various stakeholders integrating the chain; the lack of<br />communication among them, but highlight commercial relationship among producers,<br />suppliers of equipment, feed and breeding stock; placing the producer as the weakest<br />point in the chain, only as raw material supplier. Producers are heterogeneous and have<br />mainly two types of farms; backyard farming and semi-technical. The spatial distribution<br />map of 33 producers was obtained.</p> <p><strong>Limitations of the study / Implications:</strong> Although rabbit farming is an important<br />complementary activity to food production, the study showed that in the area there are<br />no links among the various agents that integrate the production chain. There is only the<br />mere commercial relationship.<br /><strong>Findings / Conclusions:</strong> It is concluded that the null organization of producers keeps<br />them excluded from the productive value chain.</p> María Evangelina Galán-Caballero, Miguel Jorge Escalona-Maurice, María Josefa Jiménez-Moreno, Oliverio Hernández-Romero, Ignacio Caamal-Cahuich, Gustavo3 Velázquez-Marzano Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Productive response of creole lambs fed integral diets with Samanea saman (Jacq.) Merr. pods <p><strong>Objective: </strong>To evaluate the productive variables and the digestibility of the nutrients of an integral diet for lambs with increasing inclusion of <em>Samanea saman</em> pods.</p> <p><strong>Design/methodology/approach</strong>: 24 creole lambs (initial weight of 20.6 ± 0.3 kg) distributed in a completely randomized experimental design were used. The treatments were: T1, 0%, T2, 12.5%, and T3, 25% of <em>Samanea saman</em> pod inclusion. The productive variables and the digestibility of the nutrients were evaluated and compared with the Tukey test (? = 0.05); meanwhile, the response to the increasing content of <em>Samanea saman</em> was evaluated by orthogonal contrasts. The variables dry matter intake (DMI), daily weight gain (DWG) and feed conversion (FC) showed no differences (p &gt; 0.05) between treatments.</p> <p><strong>Results:</strong> Dry matter digestibility (DMD) and organic matter digestibility (OMD) increased (p &lt;0.05) linearly, with increasing pod content. The digestibility of the neutral detergent fiber (DNDF) and acid (DADF) decreased (p &lt; 0.05) linearly as the inclusion of <em>Samanea saman</em> pod increased in the diets.</p> <p><strong>Limitations on study/implications:</strong> The substitution of soybean pulp by <em>Samanea saman </em>pod in integral diets does not affect the productive response of fattening lambs.</p> <p><strong>Findings/conclusions:</strong> The use of <em>S. saman</em> pod is proposed as a regionally available food alternative in the feeding of ruminants in the tropics.</p> Jerónimo Herrera-Pérez, Ulises Carbajal-Márquez, Nicolás Torres-Salado, Paulino Sánchez-Santillán, Omar Ramírez-Reynoso, Adelaido R. Rojas-García, Marco Antonio Ayala-Monter Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Genetic transformation of Paulownia elongata S. Y. Hu., mediated by Agrobacterium tumefaciens and biolistic system <p><strong>Objective:</strong> The most appropriate conditions for genetic transformation through direct (bioballistic) and indirect (Agrobacterium tumefaciens) transformation systems in Paulownia elongata were established.</p> <p><strong>Design/methodology/approach:</strong> Starting from in vitro propagation through both direct and indirect organogenesis, internodal stem segments with 0.5 to 1 cm length were determined as the best explant. The optimum dose for selection media was determined to be 15 mg L-1 of kanamycin. It was possible to obtain transgenic plants under both transformation systems. In the case of Agrobacterium tumefaciens, two hours of incubation, 48 h of co-cultivation, and optical density of 0.9 were used; while for bioballistics, the best conditions were 120 PSI of shot pressure, shot height at level 6 (16 cm), and vacuum pressure of 22 Hg mm, with particle inflow gun system (PIG).</p> <p><strong>Results:</strong> Both systems produced complete transformants, chimeras, as well as those confirmed by histochemical X-GLUC and PCR analysis, producing a total of 14 positive plants by A. tumefaciens transformation from 26 trials and ten positive plants by the bioballistic system from 30 trials; a construction with chitinase and glucanase, NPT II selection gene and the GUS reporter gene were used.</p> <p><strong>Findings/conclusions:</strong> So far, this has been the first report including integration of chitinase and glucanase genes.</p> Carlos R. Castillo-Martínez, Ma. Alejandra Gutiérrez-Espinosa, Jorge Cadena-Iñiguez, Marco T. Buenrostro-Nava, Valeria Martínez-Sias Derechos de autor 2021 Agro Productividad mié, 14 abr 2021 00:00:00 +0000 Asexual reproduction: an alternative for the propagation and conservation of papaya (Carica papaya L.) native to Guerrero, Mexico <p><strong>Objective:</strong> Evaluate the effect of three types of substrate and different shoot lengths on<br />the rooting of Carica papaya L. shoots.<br /><strong>Design/ methodology/ approach: This</strong> experiment followed a completely randomized<br />design with a 2×3 factorial arrangement. Shoots of 30 and 40 cm of length were<br />collected in March 2018 from the lateral branches of papaya plants (Carica papaya L.)<br />native to various regions of Guerrero. Shoots were placed in different substrates: 1)<br />sand, 2) Peat Moss®, and 3) sand and Peat Moss® mixture (70:30, v/v). Sixty days after<br />planting, rooting percentage, root length, plant height, stem diameter, number of leaves,<br />crown diameter, biomass fresh weight, biomass dry weight, root fresh weight, and root<br />dry weight were evaluated. Data were analyzed through an analysis of variance and a<br />mean difference test (Tukey, p?0.05).<br /><strong>Results:</strong> The rooting of 40- and 30-cm shoots was 60 and 50%, respectively. Plants<br />with the highest height, number of leaves, root length, and crown diameter derived from 240-cm shoots. Sand was the best substrate for rooting, where plants with higher fresh<br />biomass were significantly developed.<br /><strong>Study limitations/ implications:</strong> Continue study during the flowering and fruiting<br />stages.<br /><strong>Findings/ conclusions:</strong> This protocol allows the rooting of papaya shoots.</p> Elías Hernández-Castro, Arlae Rojas-López, José Luis Valenzuela-Lagarda, Juan Elías Sabino-López, Paul García-Escamilla, Abraham Monteon-Ojeda Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Characterization of fruit and vegetable waste as an alternative ruminant feed in Pachuca, Hidalgo, Mexico <p><strong>Objective:</strong> Measure and characterize the fruit and vegetable waste generated during<br />a working day in a commercial juice and fruit cocktail establishment in Pachuca,<br />Hidalgo, Mexico, for four weeks.<br /><strong>Design/ methodology/ approach:</strong> The total amount of fruit waste generated during<br />a working day in a commercial juice and smoothie establishment in Pachuca,<br />Hidalgo, Mexico, was collected Monday through Saturday for four weeks in<br />September and October 2019. Waste was weighted and separated daily into the<br />different types of fruit. We then analyzed their dry matter (DM), crude protein (CP),<br />and ash (Ash) content. The experimental design was completely randomized.<br /><strong>Results:</strong> The amount of fruit and vegetable waste was constant during the four<br />collection weeks; the total amount of waste collected was 465 kg; orange peel was<br />the most abundant waste (75%). The moisture content ranged from 75 to 94% based<br />on the type of fruit. The CP concentration ranged from 4.33 to 6.95%, except for the<br />papaya peel, which had a CP content of 11.55%.<br /><strong>Limitations/ implications:</strong> An alternative to avoid landfilling this type of organic<br />waste is to subject it to a silage-making process; this would reduce negative 2<br />environmental impacts, generate value-added products, and reduce the pressure on<br />natural resources.<br /><strong>Findings/ conclusions:</strong> The amount of fruit and vegetable waste produced every<br />week was constant for four weeks. Although their dry matter content is low, these<br />wastes, mixed with cereal straw and subjected to a silage-making process, can result<br />in value-added products, and avoid landfilling.</p> Baruch J. Coronel-López, José J. Espino-García , J. Jesús G. Peralta-Ortiz , María Guadalupe Torres-Cardona, Martín A. Meza-Nieto, Isaac Almaraz-Buendía Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Analysis of the productive and immune response of lambs infected with gastrointestinal nematodes and fed with saccharin <p><strong>Objective:</strong> Determine the productive and immune response of Blackbelly lambs infected<br />with gastrointestinal nematodes (GIN) and fed with saccharin.<br /><strong>Design/ methodology/ approach:</strong> A total of 18 Blackbelly lambs, with an initial live weight (LW) of 13.9 + 3.2 kg, were randomly assigned to three different treatments (T): T1, anthelmintic treatment + basal diet (CTah); T2, basal diet without anthelmintic treatment (STah); and T3, grazing lambs without anthelmintic treatment (STPS). This experiment followed a completely randomized design with repeated measures over time; mean values were compared using Lsmeans. The parameters evaluated included live weight (LW), fecal egg count per gram (FEC), packed-cell volume (PCV), plasma protein (PP), white blood cell<br />differential count (LEU), and IgA concentration by ELISA with Haemonchus contortus<br />and Trichostrongylus colubriformis antigens.<br /><strong>Results:</strong> STah and CTah lambs showed higher FEC (885 ± 142) and LW (29.73 ± 5.06<br />kg). Grazing lambs (STPS) had lower PCV (26.4 ± 0.5%) compared to the STah and<br />CTah lambs (27.4 to 28.4%) due to the high prevalence of H. contortus. The IgA<br />concentration in grazing lambs ranged from 20.2 to 24.5% of the positive standard<br />serum titer. The feedlot lambs (STah and CTah) showed values close to 5%.<br /><strong>Study limitations/ implications:</strong> Due to anthelmintic resistance problems, it was<br />impossible to maintain grazing lambs free of infection; therefore, this group was not<br />included.<br /><strong>Findings/ conclusions:</strong> Saccharin increases sheep resilience and achieves adequate<br />weight gains in parasitized lambs.</p> Roberto González-Garduño, Luis Matias Silva-Torres, Glafiro Torres-Hernández, María Eugenia López-Arellano, Ever del Jesus Flores-Santiago, Armando Jacinto Aguilar-Caballero, Luis Manuel Vargas-Villamil, Claudia Zaragoza-Vera Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Productive performance of rabbits fed alfalfa (Medicago sativa)- or white clover (Trifolium repens)- based diets <p><strong>Objective:</strong> Evaluate the productive performance of rabbits fed alfalfa- and white clover-<br />based diets.<br /><strong>Design/ methodology/ approach:</strong> Rabbits can consume high-fiber diets. Therefore,<br />this study evaluated a white clover-based diet (Diet 1) and an alfalfa-based diet (Diet 2).<br />The experiment was carried out during the Fall-Winter season of 2018. This study used<br />111 rabbits (males and females), weaned at 31 days of age. Diets were randomly<br />assigned to 20 cages, four to six animals per cage. In total, 56 rabbits received Diet 1<br />and 55 Diet 2. All animals had free access to feed and water during the 35-day growth<br />period. The weekly recorded response variables were live weight (LW), daily weight gain<br />(DWG), and feed conversion (FC). At 67 days of age, hot carcass yield (HCY) and cold<br />carcass yield (CCY) were determined.<br /><strong>Results:</strong> At the end of the fattening period (31 to 66 days of age), there were no<br />significant differences between the two experimental groups. The results for Diet 1 and<br />2, respectively, were the following: LW = 2012±36 and 1960±37 g, DWG = 32.2±1.572<br />and 28.4±1.60 g/animal, FC = 3.3±0.2 and 3.4±0.2 g/g, HCY = 48.0±0.5 and 55.9±0.6%,<br />and CCY = 48.1±0.5 and 55.8±0.7%.<br /><strong>Limitations/ implications:</strong> Due to the lack of significant differences (P?0.05), further<br />studies are required to better understand these legumes.<br /><strong>Findings/ conclusions:</strong> White clover could completely replace alfalfa in rabbit diets.</p> Eliseo Sosa-Montes , Josué Alavez-Ordoñez , José Enrique Estevané-Guzmán, Arturo Pro-Martínez, José Isidro Alejos-de la Fuente, Fernando González-Cerón Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Scarification treatments in chepil seeds (Crotalaria longirostrata Hook. &amp; Arn.) used to improve their germination <p><strong>Objective</strong>: The objective was to evaluate different scarification treatments to improve<br />germination in chepil seeds (Crotalaria longirostrata Hook. &amp;amp; Arn.).<br /><strong>Design/Methodology/Approach:</strong> The study was established in the School of Veterinary<br />Medicine and Zootechnics N. 2 of the Universidad Autónoma de Guerrero. The chepil<br />seeds were weighed and counted; 2 experiments were established through a CRD with<br />4 treatments of 4 repetitions each. Imbibition and germination were evaluated. The data<br />were analyzed with the statistical software package SAS® 9.0.<br /><strong>Results:</strong> The use of water at different temperatures and times presented positive results<br />in imbibition and increased the germination percentages. The treatment with water at<br />100°C until cooling reached a germination of 80%, and the control of 12.3%.</p> <p><strong>Study Limitations/Implications:</strong> Chepil is a wild species that has seeds with physical<br />dormancy, which is something that requires more research in order to accelerate and<br />increase the germination percentages.<br /><strong>Findings/Conclusions:</strong> The imbibition and germination was affected by the treatments<br />applied. Chepil seeds presented physical or superficial dormancy that may be eliminated<br />with the use of heat treatments; however, evaluations still need to be performed to<br />accelerate and find a higher percentage of germination.</p> Adelaido R. Rojas-García , María de los Á. Maldonado-Peralta, Paulino Sánchez-Santillán, Marco A. Ayala-Monter , Perpetuo Álvarez-Vázquez , Omar Ramírez-Reynoso Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Morphological characteristics of okra fruits [Abelmoschus esculentus (L.) Moench.] cultivated in the dry tropic <p><strong>Objective:</strong> The objective was to evaluate the morphological characteristics of okra fruit<br />[Abelmoschus esculentus (L.) Moench.], an endemic crop of the Afro-Mexican region, in<br />the dry tropics.<br /><strong>Design/Methodology/Approach:</strong> Materials were collected in Cuajinicuilapa, in the<br />state of Guerrero in Mexico. Using a completely randomized design (CRD), 4 repetitions<br />of 100 fruits were selected, and each was evaluated for the following: weight, number,<br />size and shape of fruits and seeds. Data were analyzed using measures of central<br />tendency, utilizing SAS.<br /><strong>Results:</strong> The fruits are heterogeneous and some are deformed, they have a long and<br />fluted shape, with an average weight of 10.4 g and 95 seeds each weighing 0.05 g. The<br />seeds are round with a conical micropyle, the testa is dark grey, and the embryo white.<br /><strong>Study Limitations/Implications:</strong> It is necessary to keep studying the morphological<br />characteristics of okra fruit for a longer period of time and to establish farming in order<br />to widen the outlook of decision making.</p> <p><strong>Findings/Conclusions</strong>: Okra fruits from backyard farming have better quality and<br />potential for fresh or processed consumption. There is a lack of management and<br />improvement of this crop.</p> Ramiro Maldonado-Peralta , Adelaido R. Rojas-García , Alejandro Romero-Bautista , María de los Á. Maldonado-Peralta, Delfina Salinas-Vargas , Elias Hernández-Castro Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Productive Performance of Sheep in an Agropastoral System on the Coast of Oaxaca, Mexico <p><strong>Objective</strong>: To determine the prolificacy and weight of lambs at birth (BW) in two<br />genotypes of hair sheep within an agropastoral system on the coast of Oaxaca, Mexico,<br />and to evaluate the effect of two sources of selenium on the performance of lambs from<br />said system during the fattening phase.<br /><strong>Design/Methodology/Approach:</strong> The study was carried out in an agropastoral system<br />(coconut palm and Cynodon dactylon grass) in Río Grande, Oaxaca. Two experiments<br />were conducted; the first studied 58 ewes distributed in a completely randomized design<br />(CRD) with factorial arrangement of 2x2x3, and focused on the following fixed effects:<br />genotype, number of births, and body condition (BC). The measured variables were<br />prolificacy and BW. The second experiment studied 23 lambs of 4 months in age that<br />were offspring of the females in experiment 1. They were distributed in a CRD with<br />three treatments: T1, without selenium provided; T2, with barium selenate provided; T3,<br />with selenomethionine provided. The dependent variables were daily weight gain<br />(DWG), dry material consumption (DMC), and feed conversion (FC).</p> <p><strong>Results:</strong> The Pelibuey ewes with one and two births and the Black Belly ewes with one<br />birth demonstrated the highest averages in prolificacy (P?0.05). The lowest averages<br />(P?0.05) were detected in ewes with BC 4 irrespective of number of births. The BW was<br />affected (P?0.05) by genotype; Black Belly lambs weighed 680 g (P?0.05) more that<br />Pelibuey lambs. The DWG, DMC and FC behaved similarly (P?0.05) between<br />treatments and their general averages were 0.114 kg day -1 , 0.679 kg day -1 , and 6.18,<br />respectively.<br /><strong>Study Limitations/Implications:</strong> In the agropastoral system, the BC of ewes limits<br />their reproductive performance. The weight of the lambs at the start of fattening<br />determines their performance during fattening.<br /><strong>Findings/Conclusions</strong>: In the agropastoral system, Pelibuey and Black Belly females<br />present adequate prolificacy averages and BW; however, it is very important that they<br />remain within BC 3. Neither of the two sources of selenium improves DWG, DMC, and<br />FC of lambs fattened in pens in the agropastoral system.</p> Ernesto Castañeda-Hidalgo, Carlos Barriga-García, Jorge Hernández-Bautista, Gisela M. Santiago-Martínez, Yuri Villegas-Aparicio, María I. Pérez-León Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 First report of Polyphagotarsonemus latus (Banks) in Apaxtleco chili (Capsicum annuum L.) cultivated in greenhouse <p><strong>Objectives:</strong> To generate information about a new host of the Polyphagotarsonemus<br />latus (Banks) mite, and to understand the damages caused by the cultivation of<br />Apatlexco chili pepper (Capsicum annuum L.) in the northern region of the state of<br />Guerrero.<br /><strong>Design/Methodology/Approach</strong>: The identification of the mite was carried out through<br />taxonomic keys and the damages caused in vegetative shoots, mature leaves and<br />flower buds were described.<br /><strong>Results:</strong> The P. latus mite was identified as causing important damage to the crops of<br />Aplaxtleco chili pepper grown in greenhouses in the state of Guerrero, Mexico, and this<br />is the first report of this mite in the Aplaxtleco chili pepper crop grown in greenhouses in<br />the state of Guerrero, Mexico.<br /><strong>Findings/Conclusions:</strong> Economic income is obtained from the cultivation of Aplaxtleco<br />chili peppers, a characteristic crop of the municipality of Aplaxtla, in the northern zone of Guerrero; therefore, knowing the identity of the P. latus mite in the Aplaxtleco chili crop<br />will help to suggest effective control methods to obtain higher yields.</p> Juan Elías Sabino-López , P. García-Escamilla , M. Espinosa-Rodríguez, Y. Durán-Trujillo , O. Talavera-Mendoza , E. Hernández-Castro Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000 Mycelial disturbance stimulates the formation of sporomes of edible ectomycorrizhal fungi associated with two neotropical pines <p><strong>Objective:</strong> To determine the effect of mycelial disturbance on the formation of sporomes<br />of two edible ectomycorrhizal fungi of great biocultural relevance in Mexico (Laccaria<br />laccata and Hebeloma leucosarx) associated to two Neotropical pines with economic<br />and ecological importance, Pinus greggii and P. montezumae.<br /><strong>Design/Methodology/Approach:</strong> Spore inoculum was produced using ground pilei of<br />the evaluated ectomycorrhizal fungi; each pine plant was inoculated with 10 7 to 10 8<br />fungal spores. A completely randomized experimental design was used with four<br />treatments and six replicates per treatment for each pine species, having a total of 48<br />experimental units, each one consisting in an inoculated tree. During two years the<br />sporome production was evaluated in the treatments with and without mycelial<br />disturbance. The duration of the experiment, since seed germination, was 5 years.<br /><strong>Results:</strong> The mycelial disturbance originated a higher formation of sporomes in both<br />fungal species, regardless of the associated tree species. The highest sporome<br />formation was recorded in plants inoculated with H. leucosarx compared to those inoculated with L. laccata in both pine species. Mycelial disturbance, originated a higher<br />number of sporomes in Pinus greggii compared to P. montezumae.<br /><strong>Study Limitations/Implications:</strong> The evaluation of factors influencing sporome<br />formation in edible ectomycorrhizal fungi requires long term experiments.<br />Findings/Conclusions: This study shows for the first time that mycelial disturbance<br />increases sporome formation in Neotropical ectomycorrhizal fungi. Additionally, a<br />differential influence of the fungal and tree species on the number of produced<br />sporomes was found. These findings shed some light on potential cultivation methods<br />for edible ectomycorrhizal mushrooms.</p> Juan Alfonso Villegas Olivera, Jesus Perez-Moreno, Gabriela Sánchez Viveros, Magdalena Martínez Reyes, Gerardo Alvarado Castillo, Juan José Almaraz Suarez, Carlos Roberto Cerdán Cabrera Derechos de autor 2021 Agro Productividad sáb, 20 mar 2021 00:00:00 +0000