Spanish Journal of Agricultural Research

Ranking and measuring the dynamics in the reasons-for-buying selected produce

2024-03-14T17:43:39+01:00

Aim of study: Individual purchasing behaviour depends on economics, psychology, marketing and sensory science. Given that the list of reasons-for-buying is almost unlimited, we have defined 14 pre-set descriptors thought to entail the more important attributes when make buying decisions within a food group of selected fruits and vegetables.

Area of study: We have used a United States buyer data base of over 175,000 observations.

Material and methods: Each household was asked to rank their first, second, and third most important reasons for buying, within the set of descriptors. The overriding goal was to gain insight into the attributes and change over time. Using empirical models, the relative importance of the attributes is shown and forecasted for a decade beyond 2021.

Main results: Price and quality were expected to be the main drivers; however, the organic attribute is one requiring significant changes in the production, inspection, distribution and marketing policies, hence considering future expectations for organics is particularly important.

Research highlights: Preferences for organics have grown, but what are the expectations a decade from now? Will that interest remain so for many years to come?

Development and evaluation of a machine vision-based cotton fertilizer applicator

2024-03-14T17:53:57+01:00

Aim of study: To develop and assess a cotton fertilizer applicator integrated with a Machine Vision Based Embedded System (MVES) to achieve precise and site-specific fertilization.

Area of study: The investigation was performed in the Indian Institute of Technology, Kharagpur.

Material and methods: The MVES included a cotton detection system with a web camera, processor (computer), and python-based algorithm, and a fertilizer metering control unit with a stepper motor, motor driver, power supply, and microcontroller. The python-based algorithm in the computer predicts the presence (or absence) of cotton plants, whenever an input image is received from the camera. Upon cotton detection, it transforms into a Boolean signal sent to the microcontroller via PySerial communication, which instructs the motor to rotate the metering unit. Motor adjusts the speed of metering unit based on machine speed measured through a hall sensor, ensuring site-specific delivery of metered fertilizer A developed lab setup tested the MVES, experimentally examining performance indicators.

Main results: The MVES obtained a MAPE of 5.71% & 8.5%, MAD 0.74 g/plant & 1.12 g/plant for urea and DAP (di-ammonium phosphate), respectively. ANOVA revealed no statistically significant effect of forward speed on the discharge fertilizer amount (p>0.05). For urea, discharge rates ranged from 1.03 g/s (at 10 rpm, 25% exposure length of metering unit) to 40.65 g/s (at 100 rpm, 100% exposure). DAP ranged from 1.43 to 47.66 g/s under similar conditions.

Research highlights: The delivered application dosage conformed the recommended dosage. The developed MVES was reliable, had a quick response, and worked properly.

Cadmium concentration in cocoa beans produced in agroforestry systems of small producers in Panama

2024-03-14T17:59:09+01:00

Aim of study: To calculate Cd concentration in cocoa plants and evaluate its relationship with available Cd and other soil properties.

Area of study: Almirante, Bocas del Toro province, Panama, in 2020-2021.

Material and methods: The study was carried out in 21 plots of eight cocoa-producing farms. The total area of each sampled plot was 300 m². Soil samples were taken at a depth of 30 cm, and samples of the leaves and fruits of cocoa trees were also taken. Descriptive statistics and correlation analyses were carried out for soil variables and Cd in plants. The relationship between bioavailable Cd and soil physicochemical variables and between soil variables and Cd in plants was evaluated. Multiple linear regression was performed using the backward selection method.

Main results: The pH was acidic (5.1) and the organic matter content of the soil was greater than 3%, suitable for immobilizing Cd from the soil. Total and bioavailable Cd averaged 0.10 mg kg^-1 and 0.02 mg kg^-1 respectively. The Cd levels in cocoa leaves exceeded the recommended levels of 0.5 mg kg^-1. The Cd concentration in the cocoa bean was low (0.25 mg kg^-1).

Research highlights: The levels of bioavailable Cd found do not exceed the United States Environment Agency toxic limits in soil. The level of Cd found in the cocoa bean is below the limit of 0.8 mg kg^-1 which is taken as a reference for chocolate, with total dry matter content ≥ 50% of the CODEX Alimentarius.

Use of B–mode and Power Doppler ultrasonography of the uterus and preovulatory follicle to predict ovulation time in Holstein cows after heat synchronization

2024-03-14T17:30:56+01:00

Aim of study: To evaluate the utility of B-mode and Power Doppler ultrasonography to predict ovulation time in Holstein cows by assessment of uterine and follicle measurements.

Area of study: Galicia, NW Spain

Material and methods: 33 Holstein cows were examined every 12 h until ovulation. Measurements for the ratio endometrium/myometrium (END/MYO), uterine lumen (UL), diameter of the dominant follicle (DF), and Power Doppler of the dominant follicle and corpus luteum were recorded. The times of onset of heat, maximum heat (MHA) and heat finalization were obtained from the database of monitoring devices. Blood samples were taken at each examination for progesterone (P4) determination. Data were analyzed using one-way ANOVA and Pearson’s χ² tests.

Main results: For UL, time -6 (1.53 mm) with respect to ovulation (time 0) significantly differed from time -42 (5.70 mm). Concerning DF, significant differences were observed between time -6 (20.48 mm) and time -54 (16.60 mm). As for P4, significant differences were found between time -6 (0.34 ng/mL) and time -54 (1.03 ng/mL). Considering MHA, significant differences were observed for the UL between after and before/during groups; for DF, significant differences were found before and after MHA. As for heat, the UL significantly differed between after and before/during groups. Significant differences were found for the percentage of cows with Doppler signal in the ovulatory follicle and corpus luteum concerning MHA and heat factors.

Research highlights: The use of Power Doppler to predict ovulation time needs to be refined. The END/MYO and UL measurements could be useful to identify cows in heat, but inaccurate to determine ovulation.

Effects of the encapsulation of Lactobacillus acidophilus and Spirulina platensis on carcass yield and meat quality of broilers under heat stress conditions

2024-03-14T17:55:58+01:00

Aim of study: To evaluate the effects of adding Lactobacillus acidophilus (LA), Spirulina platensis (SP) and the encapsulation of LA on the relative weights of carcass parts and meat quality of broilers subjected to heat stress.

Area of study: The work was performed at the University of Jiroft, Iran.

Material and methods: Two hundred forty 1-day-old male broilers (Ross 308) were used in a completely randomized design, with six treatments and four replicates (cages, 10 birds per cage). Dietary treatments included: (i) corn-soybean as control diet (CON), (ii) 0.02% LA, (iii) 1% SP, (iv) 0.02% LA + 1% SP, (v) 0.02% of encapsulated LA, and (vi) 0.02% encapsulated LA + 1% SP.

Main results: The relative weight of the carcass increased in all experimental groups except in the 0.02% LA encapsulated group (p˂0.05). Birds fed diets containing LA+SP (0.02% LA+ 1%SP and 0.02% LA encapsulated+1% SP) had a significantly higher relative weight of the breast (p˂0.05). Dietary supplementation with SP, LA+SP, and encapsulated LA+SP significantly increased water holding capacity and decreased cook loss, respectively (p˂0.05), whereas dietary LA+SP and encapsulated LA+SP decreased drip loss (p<0.05), compared to the CON group. Moisture and pH were not significantly affected by the dietary treatments (p˃0.05). The malondialdehyde content of thigh and breast meat at 30 and 37 days after the slaughter was reduced (p˂0.05) in the SP, LA+SP, and LA encapsulated +SP groups.

Research highlights: Based on results, including LA, SP and encapsulated LA in broilerʼs feeds were effective in improving carcass yield, quality and oxidative stability of broiler meat under heat stress condition.

Feeding formaldehyde-treated sesame meal to lactating Murciano-Granadina goats: implications on milk yield and composition, digestibility, rumen fermentation, and blood metabolites

2024-03-14T18:01:05+01:00

Aim of study: To investigate the effect of substituting sesame meal (SM) treated with different levels of formaldehyde instead of soybean meal (SBM) on rumen fermentation, milk composition, and hemato-chemical parameters in lactating goats.

Area of study: Kerman, Iran.

Material and methods: Forty Murciano-Granadina goats in mid-lactation were allocated to four groups as a completely randomized design for 56 d. They were fed with diets containing: 1) SBM (control), 2) 12.5% untreated SM, 3) 12.5% treated SM with 0.8 g formaldehyde/100g crude protein (CP), and 4) 12.5% treated SM with 1.2 g formaldehyde/100g CP.

Main results: The goats fed diet containing SM treated with 1.2 g of formaldehyde had greater (p < 0.01) intake of dry matter, CP and metabolizable energy (ME) than other groups. Milk yield and milk protein in goats fed diets containing 1.2 g formaldehyde-treated SM were greater than others (p < 0.01). Fat-corrected milk and total solids in groups fed diets containing formaldehyde-treated and untreated SM were greater than those in control (p < 0.01). Goats fed control diet showed a greater proportion of saturated fatty acids (SFA), and short and medium-chain FA in their milk compared to other groups (p < 0.01). Partial replacement of SBM with formaldehyde-treated or untreated SM increased milk unsaturated FA and long-chain FA (p < 0.01). Goats fed formaldehyde-treated SM had lower acetate production (p < 0.01).

Research highlights: Partial replacement of SBM with formaldehyde-treated SM can be suggested to increase lactating goats' performance without adverse effects on their health.

Maize yield and grain quality response to foliar-applied phosphorus in a soil testing high in P

2024-03-14T18:13:08+01:00

Aim of study: To test the effect of foliar and granular P fertilizer application on maize performance planted under permanent beds from 2012 to 2019 in a soil testing high in P.

Area of study: This field experiment was located in the eastern region of the trans-Mexican volcanic belt.

Material and methods: Three P treatments, foliar and granular (band and broadcast), and a control (0P) plot were allocated in an randomized complete block design in six replications.

Main results: Year-P treatment interaction was significant for yield, agronomic efficiency (AE), and recovery efficiency (RE). Contrastingly, grain quality parameters measured as bulk density and thousand grain weight were only affected by year’s main effect. Yield, AE, and RE were generally more responsive to the foliar than the granular P application. These parameters varied in each treatment according to precipitation accumulated in 40 days during the bracketing-silking period (40d PP) and heat units during the grain filling stage [GDD(t-m)]. As 40d PP increased, yield and AE improved, while RE decreased; as GDD(t-m) increased, yield and grain quality improved. Initial soil available P (46 mg/kg) decreased 26% due to foliar P application.

Research highlights: Results suggest that replacing the granular P with foliar P fertilization is an option to mine soil to an acceptable P level without adverse effects on maize performance.

Experts’ opinion on the sustainable use of nematicides in Mediterranean intensive horticulture

2024-03-14T17:33:56+01:00

Aim of study: Root-knot nematodes are considered a common limiting factor to reaching premium quality and economically viable yields in horticultural crops. Soil disinfestation with agrochemical fumigants has been the main nematode control method until their recent ban due to environmental and social concerns. This paper explores farmers and agricultural advisors’ opinion and preferences on the sustainable use of available nematode control methods, considering sustainability as an integration of nematicidal effectiveness, reduction of environmental harmful effects and preservation of human health.

Area of study: This study has been carried out between farm advisors of intensive horticultural crop areas in Southern Spain.

Material and methods: Farm advisors’ opinion and preferences on the use of nematicides was evaluated following an opinion survey and the Analytic Hierarchy Process (AHP) method. The analysis done was exploratory.

Main results: Providing that current available control methods give enough nematicidal effectiveness to get a profitable yield, the group of farm advisors showed a great consciousness on the use of sustainable alternatives for nematode control in intensive horticultural crops, prioritizing biosolarization as the first option, followed by biopesticides and fumigant nematicides in third place. The use of ozone and non-fumigant nematicides with high toxicity profiles were considered the last options, but new generation nematicides with lower ecotoxicity profiles are also considered as an important tool in sustainable nematode management.

Research highlights: These results provide a prediction of farmers' responses to the sustainable use of nematicides promoted by the European Union when agrochemical fumigants are banned.

Land leveling and cover cropping impacts on chemical and biological properties of paddy soil

2024-03-14T18:07:40+01:00

Aim of study: To examine the impact of solitary land leveling and its combination with cover cropping on the chemical and biological characteristics of paddy soil.

Area of study: This research focused on paddy fields located in Guilan Province, situated in northern Iran. Specifically, two sites were chosen for investigation, where land leveling had been conducted 5 years and 2 years prior to this study, respectively. Furthermore, cover cropping was implemented during the second year after the latter area's land leveling.

Material and methods: A total of 80 composite soil samples were collected, with 20 samples gathered from both leveled and unleveled plots at the designated study sites. Various soil chemical and biological properties such as organic carbon, total nitrogen, available phosphorus, exchangeable potassium, microbial respiration, and biomass carbon were quantified. Subsequently, a paired t-test was employed to analyze the impact of land leveling and the combined effects of land leveling with cover cropping on soil attributes.

Main results: The study revealed that five years after land leveling, there was a significant decrease in organic carbon, total nitrogen, microbial respiration, and biomass carbon. In contrast, the area leveled and cover cropped for two years exhibited higher levels of these attributes compared to adjacent unleveled parcels.

Research highlights: This study highlights the distinct effects that solitary land leveling and land leveling combined with sustainable practices like cover cropping have on soil attributes.