Spanish Journal of Agricultural Research

Mechanics for Seedling Feeding in Vegetable Transplanters: Design and Development of Semi-Automatic Systems

Ankit Sharma — 2025-01-16

Aim of study: The seedling feeding mechanism is a significant element in transplanters. The current study designed and developed two semi-automatic mechanical seedling feeding mechanisms for the tractor mounted vegetable transplanter, revolving multi-chamber disc (FMRMD) and horizontal dragging magazines (FMHDM).

Area of study: The research was conducted in the Sher-e-Kashmir University of Agricultural Sciences & Technology of Jammu, Jammu, India.

Material and methods: The FMRMD consists of 12 chambers on the revolving disc, which move clockwise and drop the seedling at the guided hole, whereas FMHDM consists of six hollow pipes that drag the seedling to the dropping point. The theoretical planting frequency of the FMRMD and FMHDM was found to be 33.94 and 34.87 plants·min-1. The developed feeding mechanisms were installed on the semi-automatic vegetable transplanter and tested in the field to investigate the effect of seedling feeding method, plug type and age on the missing index percentage for tomato and eggplant.

Main results: The first-order interaction of feeding method and plug type in the tomato and plug type and seedling age in the eggplant crop were statistically significant on the missing index. At the same time, the main effect of the feeding method was also significant on the missing index for both crops. The missing index percentage was maximum for the FMHDM and minimum for the FMRMD for both crops. The field tests of the feeding devices were successful.

Research highlights: The created technologies may be employed on commercial transplanters or for research.

Detection of mite infested saffron plants using aerial imaging and machine learning classifier

Hossein Sahabi — 2025-01-20

Aim of study: To evaluate and develop a machine learning code that uses aerial images in visible and near infrared (NIR) spectra to detect mite-infested Saffron (Crocus sativus L.) plants through processing the spectral indices to classify healthy and diseased plants. This leads to the identification of the concentration points of the bulb mites and the estimation of the percentage of infestation in the field.

Area of study: Khorasan-Razavi province, Torbat-Heydarieh, Iran.

Material and methods: Five fields were randomly selected and their red-green-blue (RGB), as a typical visible spectral image, and NIR images were taken in two consecutive years. Seven spectral vegetation indices for NIR images including NIR-band, Red-band, normalized difference vegetation index (NDVI), ratio vegetation index (RVI), difference vegetation index (DVI), difference red-nir ratio (DRN) and infrared percentage vegetation index (IPVI); and twelve indices for RGB images inlcuding red-band, green-band, blue-band, visible-band difference vegetation index (VDVI), visible atmospheric resistant index (VARI), triangular greenness index (TGI), normalized difference greenness index (NDGI), normalized green blue difference index (NGBDI), modified green red vegetation index (MGRVI), red green blue vegetation index (RGBVI), vegetative index (VEG) and excess of green index (EXG), were extracted and analysed. In order to detect affected plants, two support vector machine (SVM) classifiers with radial basis function (RBF) kernels were used separately for NIR and RGB images.

Main results: The average accuracy of the SVM classifier models were estimated to be 82.3% for NIR images and 91.4% for RGB images during the test phase. Also, the accuracy of the developed models when evaluated in the field with respect to the confusion matrix method was 75.6% and 80.3% for the classification models for NIR and RGB images, respectively.

Research highlights: RGB images were able to distinguish infested plants with better accuracy. Processing aerial images of lightweight drones could speed up the inspection of vast saffron fields.

Influence of ecologically relevant urea fertilizer concentrations on nematodes: A microcosm experiment

Rowena B. Caro-Benavides — 2025-01-15

Aim of study: Urea remains one of the most widely used chemical fertilisers in the world and is used extensively in the Philippines as a major source of nitrogen for crops. However, we have a very limited understanding of its impact on soil fauna such as nematodes. In this study, we demonstrated the suitability of the microcosm set-up to assess chemical effects on nematode communities under controlled conditions and determined the effects of urea on nematode communities.

Area of study: The soil samples were obtained from a relatively “less disturbed” field in Bukidnon, Central Mindanao and were taken for experimentation in a greenhouse at Premier Research Institute of Science and Mathematics (PRISM), Mindanao State University - Iligan Institute of Technology (MSU-IIT), Iligan City, Philippines.

Material and Methods: The soil was collected and analysed for its physiological properties. The soil was then exposed to urea concentrations (0 mg/kg, 19.67 mg/kg, 39.33 mg/kg and 78.66 mg/kg) in a microcosm for 45 days. Nematodes were then collected and processed using a modified dish method.

Main results: Firstly, the natural microcosms (without urea) showed that nematode abundance and the number of genera decreased by 28% and 35%, respectively. The results suggest that the current microcosm setup may still be useful in testing the effects of certain chemicals of interest. Secondly, no significant effects on the number of genera and diversity indices were observed with urea, except on the day 15 when nematode abundance was significantly higher at 39.33 mg/kg than at 19.67 mg/kg.

Research highlights: This study shows that the above ecologically relevant urea concentrations had no negative impact on nematode community structure during the 45-day exposure.

Effects of environmental enrichment and lack of beak trimming on aspects of health, behaviour and production of commercial turkeys

Josiane G. Busatta — 2024-11-27

Aim of study: The purpose of this study was to verify whether the insertion of a pecking object as an environmental enrichment (EE) would be sufficient to prevent the beak trimming (BT) process in turkeys.
Area of study: Southern Brazil.
Material and methods: A total of 3,116 female turkeys of the Nicholas Super Select line were equally distributed across four treatments in a 2 × 2 factorial scheme with the presence or absence of EE and BT or intact beak. The turkeys were housed at a density of 21 kg/m2 and were followed-up for 62 days until slaughter. Each week, the behaviour of the turkeys, body lesions, and performance indicators such as mortality, feed conversion, feed consumption, and weight were evaluated.
Main results: The results regarding injuries and performance showed, in most cases, better results for beak trimmed animals (p>0.05). The addition of EE was not effective in reducing the number of injuries in either debeaked or non-debeaked turkeys (p>0.05). Injurious pecking of turkeys may result from vigorous investigative pecking.
Research highlights: We can conclude that debeaking decreases the number of aggressive injuries in animals, and further research needs to be conducted to search for a possible alternative to EE to avoid BT, reduce injuries, and enhance performance.

The effect of failed transfer of passive immunity and agammaglobulinemia on the occurrence of preweaning diarrhea, pneumonia, and mortality in Holstein calves

Mely T. Olivera — 2025-01-16

Aim of study: To evaluate the effect of failed transfer of passive immunity (FPI; Brix% < 8, equivalent to serum
immunoglobulin G <10.1 g/L) and agammaglobulinemia (AG; Brix% ≤ 6.5, equal to 0 g/L serum immunoglobulin G) assessed with a digital Brix refractometer on the occurrence of pre-weaning diarrhea, pneumonia and mortality in Holstein female calves.

Area of Study: Hot-arid zone of northern Mexico (25 °N).

Material and methods: Health events and mortality records were obtained from Holstein calves (n = 4,349) in a large commercial dairy herd. Multiple logistic regression analyses were used to model the effect of the failure of passive transfer of maternal immunoglobulins or AG on preweaning diarrhea, pneumonia, and mortality of Holstein calves.

Main results: Calves with FPI 24 h post-calving had 1.9 greater odds of presenting preweaning diarrhea than herdmates not having FPI. Agammaglobulinemic calves were 2.6 times more likely to suffer preweaning diarrhea than calves not having this condition. Calves with FPI had 1.4 greater odds of having preweaning pneumonia than calves not presenting FPI. Calves with AG were 2.1 times more likely to get pneumonia than those with no AG. Episodes of diarrhea predisposed calves to pneumonia (odds ratio= 3.8). The odds of dying before 60 days of age were 1.9 times higher in calves with FPI.

Research highlights: These results reaffirm that FPI and AG 24 h post-calving increase the risk of preweaning diarrhea and pneumonia; also, diarrhea is a significant risk factor for pneumonia. These diseases alone or co-occurring in the calves markedly increase preweaning mortality.

The influence of calfhood diarrhea and pneumonia on preweaning growth and reproductive performance of Holstein heifers

Mely T. Olivera — 2025-01-31

Aim of the study: To determine the effect of diarrhea and pneumonia on preweaning weight gain and subsequent reproductive performance of Holstein heifers in a hot environment.

Study site: Hot-arid zone of northern Mexico (25 °N).

Material and methods: This study enrolled 7,809 calves from a single large commercial dairy herd. Calves´ birth and weaning weights were recorded, and subsequent reproductive performance was registered.

Main results: The preweaning daily gain in calves suffering diarrhea (573 ± 12 g/d), pneumonia (557 ± 12 g/d), and comorbidity of these diseases (520 ± 13 g/d) were lower (p<0.05) than healthy calves (594 ± 11 g/d). Heifers without diarrhea and pneumonia during the preweaning period conceived 25 days earlier (p<0.05) than herdmates suffering diarrhea comorbid with pneumonia and required 0.4 less (p<0.05) inseminations per pregnancy. The pregnancy rate for healthy heifers during the preweaning period was higher (93.6%; p<0.05) than those of their herdmates who experienced diarrhea (89.2%), pneumonia (89.8%), or both diseases (87.2%). Calves weighing ≤ 36 kg at birth were more susceptible (p<0.05) to diarrhea (incidence 13.3%) than calves ≥ 40 kg (incidence 11.6%).

Research highlights: These results highlight the substantial negative influence of diarrhea and pneumonia on preweaning weight gain and subsequent reproductive performance. Also, it was demonstrated that diarrhea is linked to low body weight at calving.

A survey of the commercial traits and antioxidant status of goat milk in Mediterranean pastoral farms

Manuel Delgado-Pertiñez — 2025-01-16

Aim of study: To enhance the viability of goat farms in Mediterranean mountain areas, studies have proposed strategies to improve the marketing of their animal products. The primary aim of this work was to provide an overview of the commercial traits and antioxidant composition of milk produced on Payoya farms. A second aim was to assess the relationships between the antioxidant capacity (TAC) and the hygiene-sanitary parameters in milk.

Area of study: Sierra de Grazalema Natural Park (Southern Spain).

Material and methods: The commercial traits (total solids, fat, protein, lactose, bacterial and somatic cell counts) and TAC of milk were determined monthly throughout the year. Milk samples were collected from sixteen Payoya farms under grazing-based management systems classified into three clusters

Main results: No significant differences were found between clusters in the milk quality. Principal changes were observed in the milk composition in different months due to the variation in the lactation stage and differences in feeding regimens. The negative correlation between the TAC and the somatic cell count contributes to the important role of antioxidants in maintaining optimal udder health. Vitamin A could be involved in this antioxidant mechanism due to the positive correlation between the TAC and retinol determined in a previous study.

Research highlights: The information generated on the quality of goat milk would contribute to establishing the records of the traceability system to guarantee that the animal products obtained are of the Payoya native breed.

The effect of breeder body mass on laying performance, egg quality, and hatching traits of Japanese quail.

Busra Ozkan — 2025-01-28

Aim of study: The aim of this research was to determine the effect of breeder body mass on egg laying performance, egg quality, and hatching traits of Japanese quail (Coturnix japonica).

Area of study: This study was carried out at the Poultry Unit and Research Centre of Çukurova University in the Republic of Türkiye.

Material and methods: In this study, a sum of 216 quails were used. The quails were divided into three experimental groups during the 5 weeks of age based on their body weight: high body mass (HBM), >310 g, medium body mass (MBM) from 290 to 310 g, and low body mass (LBM), <290 g; and then transferred to egg-laying cages. There were three replicates per group. Internal and external egg quality traits, hatching traits, and egg-laying performance were examined.

Main results: Egg production was statistically highest in the MBM group and the lowest in the HBM group (p≤0.05). The HBM group had the highest average egg weight and the lowest egg weight was observed in the LBM group (p≤0.05). The Haugh unit, albumen pH, shell thickness, yolk colour traits, shape index, albumen index, hatchability of fertile eggs, and yolk index were not statistically different among the experimental groups (p≥0.05). The fertility and hatchability of set eggs were statistically highest in the LBM group and lowest in the in the HBM group (p≤0.05).

Research highlights: Selection for HBM could improve egg weight, however; it may have a negative correlation with egg production and hatching traits.

Ex vitro propagation and phytochemical analysis of Serapias vomeracea (Burm.f.) Briq.: contribution to the conservation of Orchidaceae species

Esin Çolak — 2025-01-15

Aim of study: The primary objective of this study was to investigate the seed germination and antioxidant propertiesof Serapias vomeracea (Burm.f.) Briq. Specifically, the aims of the research were to explore the influence of the Tulasnellaceae spp, fungal isolate SVL-30 (MK250656), on germination and seedling development, compare antioxidant activity to that of ascorbic acid, analyse the phytochemical composition, and identify bioactive compounds present in the methanol extract.

Area of study: University of Ondokuz Mayıs, Faculty of Sciences, Department of Biology, Samsun, Türkiye.

Materials and methods: Pots containing S. vomeracea and SVL-30 fungus, along with a control group without fungus, were utilized for the experiment. The impact of the fungus on germination stages and seedling development was assessed. Antioxidant analysis involved determining phenolic and flavonoid content, as well as DPPH radical scavenging activity (IC50: 2.09 mg/mL). Chlorophyll and carotenoid contents were measured to evaluate the physiological health of the plant. GC-MS analysis was employed to identify 19 bioactive compounds present in the methanol extract.

Main results: The fungus significantly stimulated germination, with 83.02% of seeds germinating, and 52.66%
progressing to the seedling stage. Antioxidant analysis revealed substantial phenolic and flavonoid content in S. vomeracea seedlings, demonstrating potent antioxidant properties comparable to ascorbic acid. Chlorophyll and carotenoid contents emphasized the balanced and healthy physiology of the plant. GC-MS analysis identified 19 bioactive compounds in the methanol extract, highlighting the potential bioactivity of S. vomeracea.

Research highlights: This study furnishes valuable information on the germination, phytochemical composition, and antioxidant capacity of S. vomeracea seedlings. The research underscores the potential bioactivity of the plant, substantiated by the identification of bioactive compounds. The findings lay the groundwork for further exploration of the potential health benefits of S. vomeracea. A strategic shift towards studies emphasizing sustainable agricultural practices is recommended, aiming to balance both conservation and utilization objectives.

DNA metabarcoding of gut contents reveals natural predation by spiders on Xylella fastidiosa vectors in the southwestern Spain agroecosystem

Laura Avivar-Lozano — 2025-01-22

Aim of study: To elucidate which species and specific guilds of spiders prey on vectors of Xylella fastidiosa from agroecosystems in southwestern Spain using metabarcoding approach.

Area of study: Southwestern Spain.

Material and methods: Spiders sampling was carried out on ground cover vegetation of olive, citrus and vineyard fields using a battery powered aspirator. DNA was isolated from each sample using E.Z.N.A.® Tissue DNA kit (Omega Bio-tek). A primer pair was designed to specifically amplify DNA from the following spiders’ potential prey belonging to the order Hemiptera: Philaenus spumarius, Neophilaenus campestris, Neophilaenus lineatus, Lepyronia coleoptrata, Aphrophora sp., Cicadella viridis, and Cercopis sp. Taxonomic assignment was conducted using the MetaCOXI reference database, based on the European Nucleotide Archive (ENA) and the Barcode of Life Data System (BOLD).

Main results: Neophilaenus campestris was detected in two spider species: Enoplognatha caricis (Theridiidae) and Thanatus vulgaris (Philodromidae) (10.4% of the captured specimens). In addition, L. coleoptrata was preyed on by Haplodrassus macellinus (Gnaphosidae) (3.5%). In contrast, P. spumarius DNA was not detected in any of the spider samples. However, aphrophorid DNA was detected in the gut of spider collected in vineyards and citrus orchards but not in olive orchards. Concerning the spider guilds, aphrophorids were detected in the gut of “other hunters”, “ground hunters” and “space-web” spiders.

Research highlights: Some species of spiders found in vineyards (50% of captured specimens) consumed N. campestris.

Phenology, biological and cultural control of the new almond pest Eurytoma amygdali (Hymenoptera, Eurytomidae) in Spain

Eugenia Rodrigo — 2025-01-24

Aim of study: Eurytoma amygdali Enderlein (Hymenoptera, Eurytomidae), the almond wasp, is a new pest detected in Spain. Although the insect is present in Europe, in Spain no damage was detected until 2016, increasing substantially in the following years. The phenology of almond wasp and the natural enemies complex were investigated and the results of the parasitism rate and cultural control measures were analyzed.

Area of study: Five Spanish provinces, important regions for almond production where E. amygdali causes serious harvest losses.

Material and methods: Samples of different almond varieties were taken from ecological almond plots in the Spanish provinces of Valencia, Alicante, Albacete, Murcia and Cuenca.

Main results: The first almond wasp eggs were observed at the beginning of May and completely developed larvae, early in July. Wasp flight occurred from mid-March to late May. Two natural enemies were associated with the pest, Pyemotes amygdali Çobanoğlu & Doğanlar (Acari, Pyemotidae), and Opilo domesticus (Sturm) (Coleoptera, Cleridae). Pyemotes amygdali parasitized wasp larvae, adult females and males, and Opilio domesticus fed on wasp larvae. O. domesticus was very scarce, unlike P. amygdali. In the plots with parasitized wasps, the parasitism rate ranged from 0.6% to 44% for P. amygdali.
Our results suggest that sanitation measure was an important cultural pest control practice, because in the plantations where mummified almonds were removed, 96% of edible almonds were harvested, compared to 18% if mummified almonds were not removed from trees.

Research highlights: Cultural control could be an important measure to control the almond wasp, because it allows biological conservation control, by preserving natural enemies present in the environment and avoid the negative effect of insecticides.