Phenological Development Stages Research Articles

SEMENTES DE MAMÃO EM DIFERENTES ESTÁGIOS DE DESENVOLVIMENTO SÃO EFICAZES NO CONTROLE DO ÁCARO VERMELHO DA PALMEIRA?

Objective: To evaluate the acaricidal potential of papaya fruit seed (C. papaya L.) extracts at different phenological stages of development on the red palm mite. Methods: Extracts from green and ripe seeds, diluted at different concentrations, were sprayed on adult mites in a completely randomized design using Petri dishes with discs of dwarf coconut leaf. The acaricidal effect was assessed at intervals of 12 hours up to 72 hours after spraying. Results and Conclusion: The mortality of Roiella indica was proportional to the increase in extract concentrations for both green and ripe papaya fruit seeds. It was concluded that aqueous extracts from green and ripe papaya fruit seeds exhibit acaricidal activity against adult red palm mites under laboratory conditions. Research Implications: Papaya seeds at different stages effectively controlled red palm mites under laboratory conditions. Originality/Value: This research contributes by exploring the potential of an agricultural residue as a pest control agent in agriculture and demonstrating its potential for more sustainable agricultural practices.

Transcriptome Data Analysis Applied to Grapevine Growth Stage Identification

In agricultural production, it is fundamental to characterize the phenological stage of plants to ensure a good evaluation of the development, growth and health of crops. Phenological characterization allows for the early detection of nutritional deficiencies in plants that diminish the growth and productive yield and drastically affect the quality of their fruits. Currently, the phenological estimation of development in grapevine (Vitis vinifera) is carried out using four different schemes: Baillod and Baggiolini, Extended BBCH, Eichhorn and Lorenz, and Modified E-L. Phenological estimation requires the exhaustive evaluation of crops, which makes it intensive in terms of labor, personnel, and the time required for its application. In this work, we propose a new phenological classification based on transcriptional measures of certain genes to accurately estimate the stage of development of grapevine. There are several genomic information databases for Vitis vinifera, and the function of thousands of their genes has been widely characterized. The application of advanced molecular biology, including the massive parallel sequencing of RNA (RNA-seq), and the handling of large volumes of data provide state-of-the-art tools for the determination of phenological stages, on a global scale, of the molecular functions and processes of plants. With this aim, we applied a bioinformatic pipeline for the high-throughput quantification of RNA-seq datasets and further analysis of gene ontology terms. We identified differentially expressed genes in several datasets, and then, we associated them with the corresponding phenological stage of development. Differentially expressed genes were classified using count-based expression analysis and clustering and annotated using gene ontology data. This work contributes to the use of transcriptome data and gene expression analysis for the classification of development in plants, with a wide range of industrial applications in agriculture.

The efficacy of spatio‐temporal predictors in forecasting the risk of Cydia nigricana infestation

AbstractThe ability to estimate the risk of pest infestation can help farmers to reduce pesticide application and provide guidance that would result in better management decisions. This study tested whether different combinations of spatial and temporal risk factors may be used to predict the damage potential of pea moth, Cydia nigricana Fabricius (Lepidoptera: Tortricidae), a major pest in field pea (Pisum sativum L., Fabaceae). Over four consecutive years, the abundance of pea moth was monitored by placing pheromone traps at various field pea‐cultivation sites. We also assessed the phenological development stages and the percentage of damaged seeds per 100 pods collected from each growing pea field in a region of approximately 30 km in diameter. The study found the significant infestation risk indicators to be the time of flowering, the date on which male pea moths are first detected in the monitoring traps and the minimum distance to pea fields that were planted and harvested in the previous growing season. The combination of all three factors using a general additive model approach yielded the best results. The model proposed by this study accurately discriminated between low‐infestation and high‐infestation fields in 95% of cases.

Phenological growth and development stages of common fig (Ficus carica L.) under arid climate of India

ABSTRACT Arid region is characterised by extreme climatic condition, poor soil health and over-exploitation of natural resources. Under prevailing conditions of arid India, Ficus carica is an emerging fruit crop with high commercial value and nutritional significance. Phenological study plays an important role in ensuring efficient crop management practices, but such studies in fig have not yet been conducted in India. The present study was conducted with an aim to define and describe phenological stages of common fig cultivar ‘Diana’ in arid regions according to the Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH)-scale using two-digit numerical system. The BBCH scale markedly explains various developmental stages of crops. Seven principal growth stages, viz. bud development (0), leaf development (1), shoot development (3), inflorescence development (5), flower development (6), syconium (fig receptacle) development (7) and fruit maturation (8), and 25 secondary growth stages of fig have been described. The sequential progression of principal growth stages of fig indicated temporal variation in growth pattern as well as overlapping of secondary growth stages. Phenological description will act as a pragmatic approach to define growth stages in order to facilitate timely agronomic practices such as canopy management, nutrient management and irrigation scheduling, pest and disease management. Since fig is considered one of the important minor fruits of India, a detailed phenological description will be instrumental in enhancing its potential in arid and semi-arid regions.

Winter Wheat Crop Models Improve Growth Simulation by Including Phenological Response to Water-Deficit Stress

AbstractCrop models can provide insights into the impacts of climate and management on crop growth and yield, but most currently are limited by overly simplistic assumptions about phenological development and response to water stress. We assessed winter wheat growth and yield performance of three crop models with lineage to the EPIC crop submodel. SWAT adopted the EPIC approach with few modifications, WEPS added new biomass accumulation, partitioning, and canopy approaches linked to key phenological development stages, and UPGM added to WEPS a detailed phenology component simulating responses to water-deficit stress. The models were evaluated with default parameters and compared to experimental data for winter wheat (Triticum aestivum L.) from two sites and a range of water-stress conditions for yield, aboveground biomass, biomass partitioning, canopy height, harvest index, and leaf area index. All models simulated yield very well (index of agreement [d] ≥ 0.93), but differences in model performance were increasingly evident for biomass (d = 0.91 [WEPS] to 0.86 [SWAT]), final canopy height (d = 0.68 [UPGM] to 0.44 [SWAT]), and harvest index (d = 0.61 [WEPS] to 0.43 [SWAT]). Errors in biomass simulation were most evident in the grain-filling period late in the growing season. Both WEPS and UPGM exhibited improved simulation of biomass and other response variables by including more explicit simulation of phenological response to water stress. The consistent improvement in winter wheat growth and yield simulation achieved with detailed phenology simulation provides an incentive to develop and test detailed phenology simulation components for other crops: currently 11 crops are simulated in UPGM, although the phenological parameters are uncalibrated. Better modeling linkages of water-stressed phenological development with other physiological processes will be critical to inform crop production where water stress and irrigation limitation are concerns.

Modeling of soil moisture and water fluxes in a maize field for the optimization of irrigation

Precision irrigation is becoming more and more important in agricultural crop production due to the limited water resources resulting from the negative effects of climate change. Modeling of irrigation can support decision makers in the maintenance of the quantitative and qualitative parameters of the cultivated crops, while improving the efficiency of water consumption. In the present paper, a 3D hydrodynamic model was created in the HYDRUS environment to support the modeling of the temporal changes and spatial variations in the water balance (WB) of a maize cultivated Hungarian study site, thereby providing inputs for irrigation scheduling and variable rate irrigation for stakeholders. Beside soil physical parameters, crop evapotranspiration (ETc) values were also considered as model inputs for the phenological crop development stages of the maize from the sowing to the harvesting. This period was between the 3rd of May and the 10th of September in 2020 and the 20th of May and 14th of September for the year 2021. The performance of the model for soil moisture conditions were validated by on-field soil moisture measurements. The overall performance (full vegetation period) of the model was good (r2 = 0.88 for 2020 and r2 = 0.91 for 2021), but slightly varied among different phenological stages. Based on the model, the water balance of the investigated area was determined without any irrigation, alongside the cumulative water fluxes (CWF) through the boundaries including the root water uptake (RWU) of the maize as well. The results revealed that the incoming precipitation was not sufficient to supplement the water content in the soil to the optimal soil moisture range, except when the precipitation level is high enough to balance it. It was concluded that the water balance was negative for the investigated time periods without any irrigation. The specific water deficit (WD) values were calculated considering the area of the study site, which is 1439 m3/ha for 2020 and 2068 m3/ha for 2021. From the obtained results, optimal irrigation schedules were presented to keep the soil moisture content in the optimal range (20.92–14.41 V/V%) in the modeled area for two different vegetation periods. It was found that due to the irrigation the crop water productivity (CWP) increased by 6% and 4% in 2020 and 2021. Overall, the model is able to cope with changing circumstances that could help to mitigate the negative effects of climate change with the reasonable use of limited water resources in the future.

Exploring DSSAT Model Genetic Coefficient Estimation Methodologies for Chickpea in Bundelkhand Region of Uttar Pradesh, India

In modern crop production, essential factors that contribute to narrowing yield gaps and minimizing production costs include making informed decisions about the selection of plant varieties, determining optimal sowing dates, determining appropriate plant populations, selecting suitable fertilizer rates, and implementing effective pest control methods. Two field experiments were conducted during the Rabi seasons of 2021 and 2022 at ICAR-Indian Institute of Pulses Research (IIPR), Kanpur using split-plot experimental design, where the main plots were three different sowing dates (20-25th October, November 10-15th, and 25th November-5th December), and the sub-plots were four chickpea cultivars (JG 16, RVG 202, IPC-07-66, and IPC-05-62), each with three replications. The genetic coefficients of the cultivars were estimated using both the iterative process (IP) and Generalized Likelihood Uncertainty Estimation (GLUE) methods in DSSAT v 4.7 to simulate the yields. Upon model validation, it was found that the average relative error (ARE) in predicting grain yield across the different sowing windows was between -25.7% to 29.1% when using the iterative process, while ARE was between -23.4% to 19% when using GLUE. The findings report more accurate simulations of chickpea growth and phenological development stages were recorded in normal sowings. And the model calibration suggest that GLUE provided superior estimates of genetic coefficients compared to the IP method. Therefore, it can be inferred that Glue is a more user-friendly and precise method.

Corn Phenology Detection Using the Derivative Dynamic Time Warping Method and Sentinel-2 Time Series

Accurate determination of crop phenology information is essential for effective field management and decision-making processes. Remote sensing time series analyses are widely employed to extract the phenological stages. Each crop’s phenological stage has its unique characteristic on the crop plant, while the satellite-derived crop phenology refers to some key transition dates in time series satellite observations. Current techniques primarily estimate specific phenological stages by detecting points with distinctive features on the remote sensing time series curve. But these stages may be different from the Biologische Bundesanstalt, Bundessortenamt and CHemical Industry (BBCH) scale, which is commonly used to identify the phenological development stages of crops. Moreover, when aiming to extract various phenological stages concurrently, it becomes necessary to adjust the extraction strategy for each unique feature. This need for distinct strategies at each stage heightens the complexity of simultaneous extraction. In this study, we utilize the Sentinel-2 Normalized Difference Vegetation Index (NDVI) time series data and propose a phenology extraction framework based on the Derivative Dynamic Time Warping (DDTW) algorithm. This method is capable of simultaneously extracting complete phenological stages, and the results demonstrate that the Root Mean Square Errors (RMSEs, days) of detected phenology on the BBCH scale for corn were less than 6 days overall.

Comparison of deep learning methods for grapevine growth stage recognition

Monitoring the phenological development stages of grapes represents a challenge in viticulture. It includes the phenological distinction of the growth stages of grapevines and the continuous technological developments, especially in computer vision, enabling a detailed classification of economically relevant development stages of grapes. In the present work, we show that based on a cascading computer vision approach, the development stages of grapes can be classified and distinguished at the micro level. In a comparative experiment (ResNet, DenseNet, InceptionV3), it could be shown that a ResNet architecture provides the best classification results with an average accuracy of 88.1%.

A Multispectral UAV Imagery Dataset of Wheat, Soybean and Barley Crops in East Kazakhstan

This study introduces a dataset of crop imagery captured during the 2022 growing season in the Eastern Kazakhstan region. The images were acquired using a multispectral camera mounted on an unmanned aerial vehicle (DJI Phantom 4). The agricultural land, encompassing 27 hectares and cultivated with wheat, barley, and soybean, was subjected to five aerial multispectral photography sessions throughout the growing season. This facilitated thorough monitoring of the most important phenological stages of crop development in the experimental design, which consisted of 27 plots, each covering one hectare. The collected imagery underwent enhancement and expansion, integrating a sixth band that embodies the normalized difference vegetation index (NDVI) values in conjunction with the original five multispectral bands (Blue, Green, Red, Red Edge, and Near Infrared Red). This amplification enables a more effective evaluation of vegetation health and growth, rendering the enriched dataset a valuable resource for the progression and validation of crop monitoring and yield prediction models, as well as for the exploration of precision agriculture methodologies.

Functional growth analysis of diploid potato varieties (Solanum tuberosum Phureja group)

The growth analysis is relevant to understanding and comparing in terms of physiological and productive behavior varieties. The study aims to determine the accumulation and distribution of dry matter through different phenological stages of development in four diploid potato varieties. For this, in a randomized complete block design with three replications, four varieties of diploid potato were evaluated: Paola, Violeta, Primavera, and Paysandú. Based on direct measurements of leaf area and dry matter of each organ, it was computed the growth indices of relative growth rate (RGR), net assimilation rate (NAR), leaf area relation (LAR), and source-sink relation. The duration of development stages of flowering, fruit, and tuber development was measured in terms of thermal time. Furthermore, the number of stems, stolons, and tubers was measured, and the yield was registered at the cycle end. The varieties Paola and Primavera reached a greater accumulation of dry matter in each organ and a greater number of tubers by plant about the varieties Paysandú and Violeta. The organs with the greater biomass accumulated were the leaves, stems, and tubers. The source and demand power had a considerable correlation between the NAR and RGR, which increased toward the end of the cycle for Paola and Primavera varieties. The yield and the beginning and duration of the growth stages were related to the season and the varieties.

RESEARCH ASSESSMENT OF THE QUALITY A LEGUMES BY ECONOMIC AND VALUE INDICATORS

The article analyzes global climate changes, which lead to a decrease in the sustainable production of agricultural products, as well as increased attention of the world community to the problems of ensuring food security, which requires innovative approaches to adapting agribusiness to new operating conditions. It has been established that the International Food and Agriculture Organization of the United Nations (FAO) is currently actively implementing a strategic action plan for the adaptation of agriculture to climate change, which is based on the reorientation of agro-food systems in the direction of innovative and mostly carbon-neutral climate-optimized agribusiness. It has been proven that the current trends in increasing prices for mineral fertilizers and energy carriers encourage the search for technologies for the cultivation of leguminous crops, which combine effective agrobiological measures to optimize their nutrition through the use of inoculation, a line of modern microfertilizers and their combinations, taking into account the critical phenological stages of plant development. which ultimately guarantees the realization of both the adaptive potential of the culture and the productive potential of its varieties. It is for these reasons that the scientific substantiation and development of measures to optimize lentil nutrition in the complex of modern agrotechnological methods of its cultivation in the conditions of the right-bank forest-steppe, aimed at ensuring a stable level of productivity with the preservation of quality indicators under the conditions of modern trends towards unstable moisture supply against the background of increasing average daily temperatures, is an urgent task. which requires scientific generalization and solution. The article provides an assessment of the quality of the grain of leguminous crops and highlights their main economic and value indicators, which are regulated by current standards. The assortment of leguminous crops, as well as their importance for the agricultural production of Ukraine, is presented. The issue of harmonization of the main regulatory documents regarding grain and leguminous crops with the requirements of the European Union for a more effective entry of Ukraine into the European and world markets has been studied. Analyzes of certification of grain and leguminous crops were carried out. The validity period of the certificate attesting the sowing quality of seeds has been determined. The concept of quality from the point of view of the consumer of legumes and their processing products is singled out, which is closely related to the aspect of their safety for the consumer's health. The scientific rationale for the development of measures to optimize modern agrotechnological methods of cultivation in the conditions of the right-bank forest-steppe, aimed at ensuring the stability of quality indicators against the background of increasing average daily temperatures, is provided.

Değişik Gelişme Dönemlerinde Yapılan Yaprak Alma ve Uç Alma Uygulamalarının Asma Yaprak Alanı Özelliklerine Etkisi

Bu araştırma; Trakya’da, 41° 01'11.41" K ve 27°39'49.14" D enlem ve boylamlarında Michele Palieri üzüm çeşidi bağında yürütülmüştür. Omcalara farklı yaprak alma - uç alma uygulamaları farklı fenolojik gelişme aşamalarında uygulanmış ve bunların yaprak özelliklerine etkisi araştırılmıştır. Deneme 2018-2019 ve 2019-2020 gelişme periyotlarında yürütülmüştür. Denemede 3 değişik gelişme döneminde (Tane Tutumu, İri Koruk, Ben Düşme) ve 4 farklı uygulama (Kontrol, Uç Alma, Yaprak Alma ve Yaprak Alma+Uç Alma) yapılmıştır. Yaprak alanı özelliklerini belirlemek için; fenolojik gelişme aşamaları, ortalama ana yaprak ve koltuk yaprak alanı (cm2), omca başına ana yaprak ve koltuk yaprak alanı (cm2 omca-1), omca başına toplam yaprak alanı (cm2 omca-1), dekara verim (kg da-1), bir kilogram üzüme düşen gerçek yaprak alanı (cm2 kg-1) doğrudan güneş gören yaprak alanı (m2 da-1) ve bir kilogram üzüme düşen güneş gören yaprak alanı (cm2 kg-1) hesaplamaları yapılmıştır. Sonuç olarak; Tekirdağ ilinde Michele Palieri sofralık üzüm çeşidinde İri Koruk döneminde gerçekleştirilen Yaprak Alma ve Yaprak Alma+Uç Alma uygulamalarının yaprak alanlarını artırdığı belirlenmiştir.

Impact of Seed Treatment with Imidacloprid, Clothianidin and Thiamethoxam on Soil, Plants, Bees and Hive Products

This paper presents studies performed for the monitoring of imidacloprid, clothianidin and thiamethoxam residues applied as seed treatment in rapeseed (Brassica napus ssp. oleifera), maize (Zea mays) and sunflower crops (Helianthus annuus). The experiments were located in representative areas of the mentioned crops. Residue levels were determined in plant samples at different phenological development stages, including flowers, as well as in bees and hive products (pollen, honeycomb, honey) by liquid chromatography/tandem mass spectroscopy (LC-MS/MS). The analyses were performed in ISO 17025-accredited laboratories, referring to the limit of quantification (LOQ), characteristic of the method used to determine the residues. In 2019, the percentage of samples that contained residues of the three substances, applied to the seed, was 16.39%, representing 20 samples out of the total of 122 analyzed samples. In 2020, 10 samples contained neonicotinoid residues above the LOQ, including 5 soil samples and 5 plant samples, representing 6.17% of the total samples. In 2021, from 149 samples with neonicotinoid applied as seed treatment, residues were identified in 12 soil samples and 11 plant samples, representing 15.43% of the total number of samples. In 2022, only 12 soil samples and 1 pasture sample contained residues above the LOQ. The results show that the highest percentage of samples with residues above the LOQ was recorded by the soil samples, while the flower and bee samples had the lowest percentages of samples with residues above the LOQ; no residues of the three neonicotinoid substances were identified in the honey samples.

Effect of glyphosate in Johnsongrass submitted to different soil water potentials

This work aimed to study the efficiency of herbicide glyphosate to control Johnsongrass plants (Sorghum halepense) in different phenological stages of development and when submitted to different types of soil water potentials. The study was conducted in a completely randomized design, with four repetitions. The treatments were arranged in a triple factor scheme 3 × 3 × 2, being: three soil water conditions [no water deficit (−0.03 MPa), intermediate water deficit (−0.07 MPa), and high water deficit (−1.5 MPa)], associated with three doses of glyphosate (0.0, 270.0, and 540.0 g a.e. ha−1) applied in two phenological stages (4–6 leaves and 1–3 tillers). Visual control evaluations were conducted at 7, 14, 21, and 35 days after the herbicide application. Biometric and morphophysiological parameters were also analyzed. With the increase of water restriction, there was a decrease in Johnsongrass morphophysiological components, such as specific leaf area, stomatal conductance, and the difference between environment and leaf temperature, as well as the accumulation of aerial part and roots dry matter, independently of the phenological stage evaluated. The development stage of Johnsongrass influenced the control provided by glyphosate, independently of the dose used. The different water deficits studied reduced the control of glyphosate in the two Johnsongrass development stages evaluated. Severe water deficits reduced the control of glyphosate in Johnsongrass using the recommended dose. In conditions of moderate water deficit, the control was not affected. Thus, the control with lower doses can be the most affected by water deficit.

Phenological growth stages of Magnolia ×soulangeana according to the extended BBCH scale

AbstractMagnolia × soulangeana, one of the most famous ornamental trees of Magnoliaceae, is widely cultivated around the world. However, its phenological characteristics at life‐cycle scale have never been detailedly reported so far. In this article, the extended BBCH (Biologische Bundesanstalt, Bundessortenamt, und Chemische Industrie) scale was applied to divide the growth and development cycle of M. × soulangeana in both juvenile phase and adult phase, and describe the characteristics of phenological development stage, so as to provide theoretical guidance for its cultivation measures implementation. Based on the BBCH phenological scale, the processes of germination (0), leaf development (1), main stem elongation (3) and dormancy (9) were observed in the juvenile phase. Likewise, the morphological changes of organs in adult phase were abundant, and eight principal growth stages were described: vegetative bud development (0), leaf development (1), shoot development (3), reproductive development (5), flowering (6), fruit development (7), maturity of fruit (8) and dormancy (9). Our newly developed scale provides a unified standard for describing and identifying the phenological period of M. × soulangeana. In addition, it is of great significance to understand the phenological characteristics of M. × soulangeana for its breeding and cultivation management.

The Influence of Variety and Climatic Year on the Phenology of Blueberry Grown in the Banat Area, Romania

This paper’s aim was to investigate the influence of variety and the climatic year on vegetation phenophases in blueberries grown in southwest Romania, the Banat region. This study was carried out during the growing season of 2020–2022 in a blueberry plantation, for ‘Duke’, ‘Hannah’s Choice’ and ‘Elliott’ varieties. In the study, phenological traits were recorded using the BBCH phenological scale and the observation of phenotypic data was recorded as in Julian days. Thus, it is found that the duration of each phenophase characterized each variety. The calendar periods for the onset of vegetation and the duration of spring phenological development stages in varieties have differed from year to year and depended on weather conditions. In the case of the phenological stage, depending on variety, the maximum amplitude was recorded for BBCH 87 stage (75% blue fruits) of 51 days, and the minimum amplitude, of 25 days, for BBCH 51 stage (bud swell) and BBCH 59 (late pink bud). The coefficient of variation, depending on climatic year, for generative phenophases, had values between 6.5% (BBCH 67-petal fall) and 21.1% (BBCH 51-bud swell). It was found that the variety and the climatic year influence the development of vegetation phenophases. The results indicate that blueberry cultivars have demonstrated a high degree of phenotypic plasticity to respond to gradual changes in environmental conditions and are important for the evaluation of cultivar cultivation prospects in the studied area.

The Influence of End-of-Day Blue Light on the Growth, Photosynthetic, and Metabolic Parameters of Lettuce at Different Development Stages.

This study evaluates the effect of end-of-day blue (EOD B) light on the physiological response of lettuce (Lactuca sativa, Lobjoits Green Cos) at different phenological development stages. Plants were grown in a controlled environment growth chamber (day/night temperature 21 ± 2 °C; relative air humidity 60 ± 5%) under the light of light-emitting diodes (LEDs) consisting of 5% blue (B; 450 nm), 85% red (R; 660 nm), and 10% green (G; 530 nm) photosynthetic photon flux density (PPFD) at 200 µmol m−2 s−1 for 16 h d−1 (BRG, control) for 8, 15, and 25 days (BBCH 12, BBCH 14, and BBCH 18, respectively). For the EOD B treatments, lettuce plants were additionally illuminated with 100% of B light at 30 and 60 µmol m−2 s−1 PPFD for 4 h d−1 (B30 and B60, respectively). The results show that EOD B light caused the elevated shoot elongation of lettuce plants regardless of their growth stages. However, leaf width increased only in more developed lettuce plants (BBCH 18). EOD B light negatively affected the development of new leaves and fresh weight, except for seedlings (BBCH 12). Most photosynthetic and spectral leaf indices also decreased when lettuce was treated with EOD B light, especially under the PPFD level of 60 µmol m−2 s−1. Moreover, the changes in metabolic parameters such as DPPH free radical activity, free proline content, and H+-ATPase activity in lettuce showed a plant response to unfavorable conditions to EOD B light.

Early Estimation of Tomato Yield by Decision Tree Ensembles

Crop yield forecasting allows farmers to make decisions in advance to improve farm management and logistics during and after harvest. In this sense, crop yield potential maps are an asset for farmers making decisions about farm management and planning. Although scientific efforts have been made to determine crop yields from in situ information and through remote sensing, most studies are limited to evaluating data from a single date just before harvest. This has a direct negative impact on the quality and predictability of these estimates, especially for logistics. This study proposes a methodology for the early prediction of tomato yield using decision tree ensembles, vegetation spectral indices, and shape factors from images captured by multispectral sensors on board an unmanned aerial vehicle (UAV) during different phenological stages of crop development. With the predictive model developed and based on the collection of training characteristics for 6 weeks before harvest, the tomato yield was estimated for a 0.4 ha plot, obtaining an error rate of 9.28%.

Evaluating Strip and No-Till Maintenance of Perennial Groundcovers for Annual Grain Production

Perennial groundcover (PGC) merges scalable soil and water conservation with high-yielding row crops, enhancing ecosystem services of annual grain crop production. However, ineffective groundcover suppression increases competition between the groundcover and row crop, reducing row crop grain yield. The objective of this study was to assess the effectiveness of three Kentucky bluegrass (KBG) groundcover suppression methods each at narrow and wide widths on maize (Zea mays L.) growth and development in evenly spaced PGC, compared to alternating PGC swards and a no-PGC conventional tillage control. Suppression methods for evenly spaced PGC included two different strip tillage implements, completing either shallow or deep soil fracture, for mechanical suppression and a banded sprayer for no-tillage chemical suppression. We measured weekly for maize plant height, phenological stage of development, reflected red:far-red (R:FR) ratio, early vegetative and final plant density, grain and stover yield, yield components of kernel rows ear−1, kernels row−1, kernels ear−1, ear length, kernel weight, grass frequency, and weed community. In 2020, maize grain yield in the alternating PGC swards (11.38 Mg ha−1) was similar to the control (12.78 Mg ha−1) and greater than in the evenly spaced groundcover (9.62 Mg ha−1). Maize grain yield was similar for systems in 2021 (7.41 Mg ha−1), due to drought and high coefficient of variation. Weed community was similar for systems in both years. A maize competition response was observed for both suppression widths across methods. Groundcover dormancy may be needed in conjunction with effective chemical and/or mechanical groundcover suppression to support maize production in PGC.