Big data, small explanatory and predictive power: Lessons from random forest modeling of on-farm yield variability and implications for data-driven agronomy

Martin van Ittersum (2023, [Artículo])

Context: Collection and analysis of large volumes of on-farm production data are widely seen as key to understanding yield variability among farmers and improving resource-use efficiency. Objective: The aim of this study was to assess the performance of statistical and machine learning methods to explain and predict crop yield across thousands of farmers’ fields in contrasting farming systems worldwide. Methods: A large database of 10,940 field-year combinations from three countries in different stages of agricultural intensification was analyzed. Random effects models were used to partition crop yield variability and random forest models were used to explain and predict crop yield within a cross-validation scheme with data re-sampling over space and time. Results: Yield variability in relative terms was smallest for wheat and barley in the Netherlands and for wheat in Ethiopia, intermediate for rice in the Philippines, and greatest for maize in Ethiopia. Random forest models comprising a total of 87 variables explained a maximum of 65 % of cereal yield variability in the Netherlands and less than 45 % of cereal yield variability in Ethiopia and in the Philippines. Crop management related variables were important to explain and predict cereal yields in Ethiopia, while predictive (i.e., known before the growing season) climatic variables and explanatory (i.e., known during or after the growing season) climatic variables were most important to explain and predict cereal yield variability in the Philippines and in the Netherlands, respectively. Finally, model cross-validation for regions or years not seen during model training reduced the R2 considerably for most crop x country combinations, while for wheat in the Netherlands this was model dependent. Conclusion: Big data from farmers’ fields is useful to explain on-farm yield variability to some extent, but not to predict it across time and space. Significance: The results call for moderate expectations towards big data and machine learning in agronomic studies, particularly for smallholder farms in the tropics where model performance was poorest independently of the variables considered and the cross-validation scheme used.

Model Accuracy Model Precision Linear Mixed Models CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MACHINE LEARNING SUSTAINABLE INTENSIFICATION BIG DATA YIELDS MODELS AGRONOMY

Testing innovations for adoption of newer and more adapted maize varieties

Michael Ndegwa Pieter Rutsaert Jason Donovan Jordan Chamberlin (2023, [Objeto de congreso])

Changing Production Conditions Genetic Innovations Maize Hybrids CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA TESTING MAIZE VARIETIES YIELDS FARMERS EXPERIMENTATION

Enhancing maize yield in a conservation agriculture-based maize (Zea mays)- wheat (Triticum aestivum) system through efficient nitrogen management

C.M. Parihar Hari Sankar Nayak Dipaka Ranjan Sena Shankar Lal Jat Mahesh Gathala Upendra Singh (2023, [Artículo])

This study evaluated the impact of contrasting tillage and nitrogen management options on the growth, yield attributes, and yield of maize (Zea mays L.) in a conservation agriculture (CA)-based maize-wheat (Triticum aestivum L.) system. The field experiment was conducted during the rainy (kharif) seasons of 2020 and 2021 at the research farm of ICAR-Indian Agricultural Research Institute (IARI), New Delhi. The experiment was conducted in a split plot design with three tillage practices [conventional tillage with residue (CT), zero tillage with residue (ZT) and permanent beds with residue (PB)] as main plot treatments and in sub-plots five nitrogen management options [Control (without N fertilization), recommended dose of N @150 kg N/ha, Green Seeker-GS based application of split applied N, N applied as basal through urea super granules-USG + GS based application and 100% basal application of slow release fertilizer (SRF) @150 kg N/ha] with three replications. Results showed that both tillage and nitrogen management options had a significant impact on maize growth, yield attributes, and yield in both seasons. However, time to anthesis and physiological maturity were not significantly affected. Yield attributes were highest in the permanent beds and zero tillage plots, with similar numbers of grains per cob (486.1 and 468.6). The highest leaf area index (LAI) at 60 DAP was observed in PB (5.79), followed by ZT(5.68) and the lowest was recorded in CT (5.25) plots. The highest grain yield (2-year mean basis) was recorded with permanent beds plots (5516 kg/ha), while the lowest

was observed with conventional tillage (4931 kg/ha). Therefore, the study highlights the importance of CA practices for improving maize growth and yield, and suggests that farmers can achieve better results through the adoption of CA-based permanent beds and use of USG as nitrogen management option.

Green Seeker Urea Super Granules CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE UREA YIELDS ZERO TILLAGE NITROGEN

Impact of manures and fertilizers on yield and soil properties in a rice-wheat cropping system

Alison Laing Akbar Hossain (2023, [Artículo])

The use of chemical fertilizers under a rice-wheat cropping system (RWCS) has led to the emergence of micronutrient deficiency and decreased crop productivity. Thus, the experiment was conducted with the aim that the use of organic amendments would sustain productivity and improve the soil nutrient status under RWCS. A three-year experiment was conducted with different organic manures i.e. no manure (M0), farmyard manure@15 t ha-1 (M1), poultry manure@6 t ha-1(M2), press mud@15 t ha-1(M3), rice straw compost@6 t ha-1(M4) along with different levels of the recommended dose of fertilizer (RDF) i.e. 0% (F1), 75% (F2 and 100% (F3 in a split-plot design with three replications and plot size of 6 m x 1.2 m. Laboratory-based analysis of different soil as well as plant parameters was done using standard methodologies. The use of manures considerably improved the crop yield, macronutrients viz. nitrogen, phosphorus, potassium and micronutrients such as zinc, iron, manganese and copper, uptake in both the crops because of nutrient release from decomposed organic matter. Additionally, the increase in fertilizer dose increased these parameters. The system productivity was maximum recorded under F3M1 (13,052 kg ha-1) and results were statistically identical with F3M2 and F3M3. The significant upsurge of macro and micro-nutrients in soil and its correlation with yield outcomes was also observed through the combined use of manures as well as fertilizers. This study concluded that the use of 100% RDF integrated with organic manures, particularly farmyard manure would be a beneficial resource for increased crop yield, soil nutrient status and system productivity in RWCS in different regions of India.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA ORGANIC FERTILIZERS YIELDS SOIL PROPERTIES RICE WHEAT CROPPING SYSTEMS

Seasonal climate forecasts (SCFs) based risk management strategies: A case study of rainfed rice cultivation in India

Nand Lal Kushwaha Paresh Shirsath Dipaka Ranjan Sena (2022, [Artículo])

FResampler1 Seasonal Climate Forecasts Decision Support System for Agrotechnology Transfer CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CLIMATE CHANGE DECISION SUPPORT SYSTEMS YIELDS RICE RISK MANAGEMENT

Una breve pesquisa sobre Crossopetalum gaumeri (Celastraceae). To be, or not to be [endemic], that is the question

RODRIGO STEFANO DUNO DIEGO FRANCISCO ANGULO PEREZ GERMAN CARNEVALI FERNANDEZ CONCHA (2022, [Artículo])

A finales de abril del 2022, un [malvado] colega del herbario CICY informó que habíamos olvidado una especie endémica en nuestra última actualización de endemismo para la Provincia Biótica Península de Yucatán ¡Otra más! Después de algunas angustias y pesquisas sobre la planta, pensamos que era una excelente oportunidad para hablar de una hermosa (o al menos interesante) planta de la región y presentar el caso. Se trata de Crossopetalum gaumeri, de la familia Celastraceae.

ENDEMISMO FLORA FLORA AUTOCTONA FLORISTICA YUCATAN BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Influence of novel coconut oil and beeswax edible coating and MAP on postharvest shelf life and quality attributes of lemon at low temperature

Mohammad Mainuddin Molla Ashfak Ahmed Sabuz Md Abdul Matin (2023, [Artículo])

Weight loss, turning of peel colour from green to yellow and microbial infections are the major postharvest problems of lemon. Lipid-based edible coatings and modified atmospheric packaging (MAP) are effective techniques in maintaining postharvest quality of fruits for long-term storage. With this view, an investigation was conducted for the preservation of green lemon using coconut oil and beeswax edible coating and MAP during storage at low temperature. Physiologically matured lemons were collected and washed with potable water; fruit surface water was removed and then coated with coconut oil-beeswax (90:10) or only coconut oil. After coating, lemons were packaged in MAP or kept in open crates and stored at 12±1 °C and 85±5% relative humidity (RH) for 8 weeks and a week interval, the sampling was conducted. The results revealed that coconut oil-beeswax coating had immense effect on retaining shiny green colour, reducing respiration, weight loss, shrivelling and preserving firmness and ascorbic acid of lemon throughout the storage. On the other hand, MAP mainly helped to retain moisture & firmness and reduce shrivelling. Uncoated lemons kept open lost the highest amount of ascorbic acid and retained only 13.7 mg/100 g that is significantly (p < 0.05) less than the lemons of all other treatments at 8th week of storage period. While lemons coated with coconut oil-beeswax and packaged in MAP was preserved the highest amount (24.2 mg/100 g) of ascorbic acid and there was no significant difference (p < 0.05) with the amount of ascorbic acid content of lemons coated with only coconut oil and packaged in MAP at the last week (8th week) of storage. Hue angle value was 93.4 in uncoated lemons packaged in MAP while it was 113.67 in coconut oil-beeswax coated lemon kept open and 112.64 in lemon coated with coconut oil-beeswax and packaged in MAP at 8th week of storage. Based on all sensory, physical and chemical parameters uncoated lemons kept open was acceptable up to 1 week, coconut oil-beeswax coated lemon kept open was 6 weeks and coconut oil-beeswax coated lemon packaged in MAP was 8 weeks with good quality and shiny green colour.

Edible Coating Sensory Quality Hue Angle Yellowing CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA EDIBLE FILMS RESPIRATION RATE LEMONS MODIFIED ATMOSPHERE PACKAGING COLD

Las bromeliáceas epífitas ¿una fuente adicional de agua para vertebrados en selvas estacionales?

Casandra Reyes García CELENE MARISOL ESPADAS MANRIQUE ALFREDO DORANTES EUAN Manuel Jesús Cach Pérez NARCY ANAÍ PEREIRA ZALDÍVAR ROGER ARMANDO ANTONIO ORELLANA LANZA JUAN PABLO PINZON ESQUIVEL (2022, [Artículo])

Las bromeliáceas epífitas han desarrollado mecanismos para obtener agua de la llamada precipitación oculta (neblina y rocío) y para almacenar agua de lluvia en tanques que se forman en las bases de sus hojas. A lo largo de su distribución geográfica existen diversas observaciones de vertebrados que las consumen deshojándolas y masticando las bases de sus hojas. En el presente estudio reportamos estas observaciones para monos, ardillas y aves de las selvas estacionalmente secas de la península de Yucatán. Discutimos cómo dada su alta protección a la herbivoría y bajo contenido de nutrientes, no constituyen un alimento deseable, pero probablemente constituyen una fuente de acceso a agua proveniente de la neblina y el rocío para dichos vertebrados.

CALAKMUL EPÍFITAS ESPECIES CLAVE NEBLINA ROCIO VERTEBRADOS YUCATAN BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Especies de abejas sin aguijón en áreas urbanas en Yucatán. Parte II: nidos con entradas poco visibles

JOSÉ CHAVIER DE ARAUJO FREITAS (2023, [Artículo])

Existen especies de abejas sin aguijón que tienen las entradas de sus nidos poco visibles: en grietas de cavidades de árboles, paredes de construcciones urbanas, muchas veces mimetizadas y haciéndolas muy sensibles a la destrucción de estos, al momento de hacer alguna poda de árbol, remodelación o construcción. Algunos géneros de abejas en áreas urbanas y alrededores de ciudades de Yucatán que podemos identificar en esta situación son: Trigonisca, Plebeia, Cephalotrigona, y la especie Frieseomelitta nigra. La poca notoriedad de sus entradas las hace muy vulnerables a ser destruidas en ambientes antropizados.

ABEJAS SIN AGUIJON NIDOS POCO VISIBLES POLINIZADORES YUCATAN MEXICO BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) INVERTEBRADOS INVERTEBRADOS

Un registro nuevo para la península de Yucatán y México: Pavonia paludicola (Malvaceae)

GERMAN CARNEVALI FERNANDEZ CONCHA José Luis Tapia Muñoz Ivón Mercedes Ramírez Morillo RODRIGO STEFANO DUNO (2023, [Artículo])

Recientemente se publicó un reporte nuevo de una especie de la misma familia del algodón (Malvaceae), para el estado de Yucatán que resultó también un nuevo registro para la Provincia Biótica Península de Yucatán y para México. Pavonia paludicola se conoce solamente de una población en todo México y está muy cerca del hermoso pueblo de Dzilam de Bravo. En este texto se resume este descubrimiento.

DZILAM DE BRAVO MALVOIDEAE MEXICO NOVEDAD FLORISTICA YUCATAN BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) TAXONOMÍA VEGETAL TAXONOMÍA VEGETAL