ReDivia - Repositorio Digital de l'Instit Valencià d'Investigacions Agràries
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Crop recognition at orchard level in Mediterranean conditions using time series of Sentinel-2 spectral indices
Get PDFThe Valencian agricultural landscape is made up of a multitude of small-sized plots. Most remote sensing research has been focused on the discrimination of the large-scale land covers or uses, however, in Spain, crop recognition at plot level is crucial to develop management policies at different scales. This work describes preliminary work for constructing and validating a classification model for automatic identification of crops in an agricultural zone where different species of fruit trees are cultivated. The model is based on the analysis of time series of two spectral indices obtained from Sentinel-2 images and using a Fourier decomposition approach. A two-step classification procedure is proposed: a random forest classifier at pixel level, followed by a plot classification. The overall accuracy achieved was 84.18% and the Kappa index was 0.71
Induction of glandular trichomes to control whitefly-transmitted viruses in tomato crops: modulation by the natural enemy Nesidiocoris tenuis
No full textWhitefly-transmitted viruses are one of the biggest threats to tomato growing worldwide. Strategies based on the introgression of resistance traits from wild relatives are promoted to control tomato pests and diseases. Recently, a trichome-based resistance characterizing the wild species Solanum pimpinellifolium was introgressed into a cultivated tomato. An advanced backcross line (BC5S2) exhibiting the presence of acylsugars-associated type IV trichomes, which are lacking in cultivated tomatoes, was effective at controlling whiteflies (Hemiptera: Aleyrodidae) and limiting the spread of whitefly-transmitted viruses. However, at early growth stages, type IV trichomes density and acylsugars production are limited; thus, protection against whiteflies and whitefly-transmitted viruses remains irrelevant. In this work, we demonstrate that young BC5S2 tomato plants feeding-punctured by the zoophytophagous predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) displayed an increase (above 50%) in type IV trichomes density. Acylsugars production was consistently increased in N. tenuis-punctured BC5S2 plants, which was more likely associated with upregulated expression of BCKD-E2 gene related to acylsugars biosynthesis. In addition, the infestation of BC5S2 plants with N. tenuis effectively induced the expression of defensive genes involved in the jasmonic acid signaling pathway, resulting in strong repellence to B. tabaci and attractiveness to N. tenuis. Thus, by pre-plant release of N. tenuis in tomato nurseries carried out in some integrated pest management programs, type IV trichome-expressing plants can be prepared to control whiteflies and whitefly-transmitted viruses at early growth stages. This study emphasizes the advantage of reinforcing constitutive resistance using defense inducers to guarantee robust protection against pests and transmitted viruses
Welfare implications on management strategies for rearing dairy calves: A systematic review. Part 2-Social management
Get PDF·Introduction: Raising a healthy calf up to puberty is essential for optimal farm performance. It is therefore, it is necessary to promote animal welfare from the three spheres during this short period. Social management has been postulated as essential in lowering stress and consequently improving calf welfare during this period. Only the health sphere has been studied for a long time, but more recent studies have recently promoted positive experiences and emotional states from affective states or cognitive judgment and natural living spheres. A systematic review of different management strategies in rearing dairy calves according to the three spheres of animal welfare has been conducted using an electronic search strategy. ·Methods: The analysis and extraction of information from the studies were performed according to a protocol. From 1,783 publications screened, only 351 met the inclusion criteria. ·Results: The publications identified in the search can be divided into two main groups, feeding and social management, based on the main topic of the publication. This review provides an overview of social management, understood as the calf’s interaction with others around it. ·Discussion: Primary social management issues that emerged were social housing with congeners, separation from the mother and human-animal interaction, distributed in the three broad spheres of animal welfare. The review highlights unresolved questions about how social management practices affect the three spheres of animal welfare at this life stage and the need to standardize good socialization practices for this stage. In conclusion, all the information shows that social housing has improved animal welfare from affective states, cognitive judgment, and natural living spheres. However, gaps in research were identified in relation to the optimal time to separate the calf from the mother, the optimal time to group with conspecifics after birth and group size. Further research on positive welfare through socialization are needed
Injerto de Púa en Algarrobo
No full textLa película muestra paso a paso el proceso a seguir para realizar el injerto de púa en algarrobo, el desprendimiento, brotación y desarrollo posterior, así como los cuidados que ha de recibir para conseguir un resultado satisfactorio. Veremos como se prepara la púa y el portainjertos, su atado, protección, como comienza a brotar, la eliminación periódica de los brotes del patrón y su espectacular desarrollo en los meses posteriores. Una representación de como esta práctica cultural puede acortar tiempo en el desarrollo y la entrada en producción del algarrobo injertado
Modelización de las necesidades hídricas en el cultivo de brócoli. Evaluación fisiológica y agronómica
Get PDFEl incremento en la frecuencia e intensidad de los períodos de sequía al que nos enfrentamos en las últimas décadas, especialmente en climas áridos, evidencia el papel crítico que tiene y tendrá el riego de precisión en la agricultura mediterránea. En este sentido, es cada vez más común el uso de modelos para la estimación de las necesidades hídricas de los cultivos; y de tecnologías que faciliten el seguimiento del estado hídrico de los mismos. El presente trabajo tiene por objetivo evaluar las estimaciones de los requerimientos hídricos de un cultivo de brócoli proporcionados por el modelo Irrigation Advisor, en comparación con una segunda estrategia manejada por el agricultor, quien decidió el agua a aplicar. Adicionalmente, ambas estrategias se evaluaron fisiológica y agronómicamente mediante lisimetría, termografía, intercambio gaseoso y fluorescencia de clorofilas.
Los resultados obtenidos mostraron que la cantidad de riego aplicada por el agricultor durante la campaña fue un 16% menor que la aplicada en tratamiento basado en el modelo Irrigation Advisor. La correcta gestión del riego se verificó mediante un microlisímetro instalado en el tratamiento basado en el modelo Irrigation Advisor, en el que no se evidenciaron eventos importantes de percolación profunda, ni descensos significativos en el peso del depósito donde se encontraba plantado el cultivo. En cambio, la infraestimación de la dosis de riego aplicada por el agricultor generó condiciones de déficit hídrico en el suelo, mostrando episodios de estrés hídrico moderado en la planta. Dichos resultados fueron evidenciados por las medidas de termografía realizadas en campo, las cuales identificaron que el tratamiento del agricultor presentó una temperatura foliar más elevada que el tratamiento basado en Irrigation Advisor (≈ 1.5 - 2.3 °C), durante la segunda mitad del ciclo. Finalmente, las medidas de conductancia estomática y transpiración aparente; también estaban en línea con las medidas de termografía, presentando el tratamiento del agricultor unos valores significativamente inferiores (≈ 24-57%) a los del tratamiento basado en Irrigation Advisor, únicamente en la segunda mitad del ciclo de cultivo. La ausencia de diferencias significativas entre tratamientos en términos de ratio de transporte de electrones y eficiencia del fotosistema II indicaron que la limitación en conductancia estomática y transpiración observada en el tratamiento del agricultor fue causada principalmente por un cierre estomático y no por daños en el fotosistema. La respuesta agronómica del cultivo en el tratamiento del agricultor mostró una menor altura de planta durante la segunda mitad del ciclo de cultivo (≈ 80-95%), y un menor peso de la misma en el momento de la recolección (≈ 15%) que el tratamiento basado en el modelo Irrigation Advisor. Por lo tanto, una reducción del peso en términos porcentuales similar al aporte hídrico realizado en la estrategia de riego del agricultor, confirman la elevada sensibilidad del cultivo del brócoli al déficit hídrico.
El presente trabajo pone de manifiesto la precisión de las estimaciones de los requerimientos hídricos del brócoli obtenidas mediante el modelo Irrigation Advisor; así como la utilidad de las metodologías evaluadas para la monitorización del estado hídrico del cultivo, favoreciendo la optimización de los recursos hídricos en agricultura
Use of a monitoring system for heat stress to check and optimize cooling strategies
Get PDFHeat stress in dairy cows can have detrimental effects on milk production and reproduction.
Traditional indicators like the temperature-humidity index (THI) provide an estimate of
potential stress but fail to measure the actual impact on the animals. To address this, the
study utilized the SenseHub® monitoring system, which records panting, a direct indicator of
heat stress, along with intake and rumination data. The objectives of this work were to
evaluate the impact of heat stress on cows in different production phases and assess the
effectiveness of cooling strategies such as showers. The study monitored 77 cows from
various production cycles, including lactating, dry, and postpartum cows, using the
SenseHub® collar. Information on panting, intake, and rumination was collected over 24
hours, as well as daily and monthly averages from June 2022 to September 2022 in a
commercial farm located in Bétera (Valencia, Spain). THI values were recorded during the
whole experimental period. For prepartum cows, two cooling strategies were compared: 2
hours per day in three showers vs. 4 hours per day in six showers. Dry and postpartum cows
received 4 hours of cooling per day in six showers. The results showed that lactating cows
experienced the highest impact of heat stress, while dry cows were less affected. The
monitoring revealed a significant difference between day and night impacts, with the highest
panting percentage occurring during the day for lactating cows. In addition, the number of
showers did not affect to dry cows as expected. Panting duration correlated inversely with
intake and rumination activity, indicating the severity of heat stress. Descriptional analysis as
well as T-test with paired data was performed with SAS System®. The beneficial effect of
cooling on heat stress was clear during the day, but some doubts appear during the night.
The average percentage of panting animals varied depending on whether they were in the
cooling period or not. Comparing the two cooling strategies for lactating cows, no significant
biological differences were observed. Despite the positive impact of cooling, heat stress
remained high, with THI values above 72 resulting in reduced production and conception
rates. In conclusion, the monitoring system used in this work proved to be a valuable tool for
evaluating heat stress impacts and optimizing cooling strategies. However, under conditions
of high ambient humidity, further evaluation of alternative cooling strategies is necessary to
effectively mitigate the negative impacts of heat stress while optimizing available resource
Suplementación del medio de congelación de semen de conejo con quercertina
Get PDFAl ser los espermatozoides células muy sensibles al daño oxidativo, el aumento de la producción de
las especies reactivas de oxígeno (ERO) que se produce durante las etapas de congelación y descongelación
provoca un efecto perjudicial sobre los mismos. El uso de antioxidantes en los medios de congelación
puede prevenir el estrés oxidativo y mejorar las características seminales post-congelación y
con ello la capacidad fecundante del semen. Existe un creciente interés en suplementar los medios de
congelación de semen de conejo con sustancias con actividad antioxidante, ya que puede se ha observado
que pueden mejorar los parámetros de calidad seminal (Nishijima et al., 2021). La quercertina,
polifenol de origen vegetal, es un flavonoide que presenta mayor actividad antioxidante y menor toxicidad
que los antioxidantes sintéticos (Silva et al., 2012; Zhong y Zhou, 2013). La quercertina es un potente antioxidante,
utilizado en la congelación de semen de diferentes especies (bovino, ovino, por cino, equino y
humano), y es capaz de reducir el daño que el aumento de ERO produce en los espermatozoides. En
conejo, la utilización de quercertina en congelación de semen no ha sido estudiada hasta el momento.
Por ello, el objetivo del presente trabajo es evaluar el efecto de la adición de quercertina al medio de
congelación sobre diferentes parámetros seminales en conejo
Influence of maturity stage on consumer perceived quality of ‘Lane Late’ oranges. Relation between sensory properties and physicochemical parameters
No full textTrends in Rabbit Insemination Extenders for Fresh and Frozen Semen. A Review
Get PDFArtificial insemination (AI) has become a popular technique in rabbit farms worldwide. This report discusses the progress made on semen extenders used in rabbit AI, setting out the latest innovations. Fresh and frozen semen have different requirements, so the extender composition will vary depending on the type of semen used. We discuss the endocrine supplementation of extenders for ovulation induction, the use of active molecules as an alternative to conventional antibiotics and the extenders developed for rabbit sperm cryopreservation
Reducing brown rot and maintaining plum quality during cold storage with composite edible coatings containing avocado seed extract
Get PDFReduction of brown rot, caused by Monilinia fructicola, is a major challenge in the
postharvest storage of fresh Japanese plums (Prunus salicina Lindl.), which are highly
perishable. The use of plant extracts with antifungal properties could be a sustainable natural
alternative to polluting chemical fungicides for brown rot control. An extract obtained from
avocado seeds (AVS) was found to completely inhibit the in vitro fungal growth of M.
fructicola. This extract was then incorporated into composite edible coating matrixes based
on hydroxypropyl methylcellulose (HPMC) or Arabic gum (AG) as hydrocolloids and beeswax
as lipid. Coated fruits were stored for 5 weeks at 1 °C, followed by 3 days at 7 °C and 5 days
of shelf life at 20 °C, simulating cold storage, transportation, and shelf life, respectively. After
cold storage, the HPMC-AVS and AG-AVS coatings reduced disease incidence by 30% with
respect to uncoated control fruit and disease severity by 50 and 62%, respectively. After
shelf life, AG-AVS significantly reduced disease incidence and severity by 13 and 42%,
respectively. The coatings also reduced the fruit respiration rate, preserved fruit firmness and
alleviated chilling injury symptoms. Additionally, the coatings had no impact on the fruit
physicochemical and sensory quality, and AG-AVS improved fruit gloss. These findings show
the potential of composite edible coatings incorporating AVS extract to reduce brown rot and
preserve plum postharvest quality