ReDivia - Repositorio Digital de l'Instit Valencià d'Investigacions Agràries
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Cost-Effective and Time-Efficient Molecular Assisted Selection for Ppv Resistance in Apricot Based on ParPMC2 Allele-Specific PCR
Get PDFPlum pox virus (PPV) is the most important limiting factor for apricot (Prunus armeniaca L.) production worldwide, and development of resistant cultivars has been proven to be the best solution in the long-term. However, just like in other woody species, apricot breeding is highly time and space demanding, and this is particularly true for PPV resistance phenotyping. Therefore, marker-assisted selection (MAS) may be very helpful to speed up breeding programs. Tightly linked ParPMC1 and ParPMC2, meprin and TRAF-C homology (MATH)-domain-containing genes have been proposed as host susceptibility genes required for PPV infection. Contribution of additional genes to PPV resistance cannot be discarded, but all available studies undoubtedly show a strong correlation between ParPMC2-resistant alleles (ParPMC2res) and PPV resistance. The ParPMC2res allele was shown to carry a 5-bp deletion (ParPMC2-del) within the second exon that has been characterized as a molecular marker suitable for MAS (PMC2). Based on this finding, we propose here a method for PPV resistance selection in apricot by combining high-throughput DNA extraction of 384 samples in 2 working days and the allele-specific genotyping of PMC2 on agarose gel. Moreover, the PMC2 genotype has been determined by PCR or by using whole-genome sequences (WGS) in 175 apricot accessions. These results were complemented with phenotypic and/or genotypic data available in the literature to reach a total of 325 apricot accessions. As a whole, we conclude that this is a time-efficient, cost-effective and straightforward method for PPV resistance screening that can be highly useful for apricot breeding programs
Sensitivity of Zasmidium citri-griseum to Fenbuconazole and Control of Citrus Greasy Spot in Panama
Get PDFCitrus greasy spot, caused by Zasmidium citri-griseum ( = Mycosphaerella citri) is the most prevalent fungal disease of citrus in Panama, causing premature defoliation and yield reduction. Fungicide applications are generally needed for the control of greasy spot. In this study, the sensitivity to fenbuconazole of 34 isolates of Z. citri-griseum from Panama was determined by calculating the effective concentration needed to reduce mycelial growth by 50% (EC50). Two field trials were conducted from 2011 to 2013, to evaluate the efficacy of fenbuconazole to reduce disease severity and yield loss. The EC50 values for fenbuconazole ranged from 0.09 to 7.62 μg mL−1, with a mean EC50 value of 2.66 ± 0.36 SE μg mL−1 for mycelial growth. These data can be used for monitoring sensitivity shifts in Z. citri-griseum to fenbuconazole and reduce risk of fungicide resistance in Panama. In the field trials, sprays with fenbuconazole significantly reduced (p 0.05) were detected in yield
Effect of the refrigeration system on in vitro quality and in vivo fertility of goat buck sperm
Get PDFCooling goat sperm insemination doses to 4 °C causes a delay in their delivery. However, chilling these doses during the transportation period could expedite their delivery and the insemination process. In this study, an economical and simple apparatus for chilling goat semen doses in itinere was developed, and the in vitro quality and in vivo fertility of these doses were compared with those chilled by means of a programmable water bath in the laboratory at a rate of −0.18 °C/min. Of the tested prototypes, the one that provided an optimal combination of the chilling rate (average of −0.09 °C/min) and time required to reach 4 °C (3 h 45 min) was selected for further testing. Immediately after chilling and 24 h later, the doses chilled in the prototype were determined to be of higher quality than the samples chilled in the programmable water bath. Finally, the kidding rate was similar between the doses chilled in the programmable water bath (61.7% ± 7.1%) and in the prototype (56.1% ± 5.9%). In conclusion, successful chilling of goat sperm doses during transport is possible, thereby accelerating the delivery of insemination doses
El panorama varietal y los nuevos patrones. Análisis de la situación actual
Get PDFLa utilización de patrones es preceptiva en los cítricos que se producen en España, ya que todas
las variedades cultivadas, ya sean naranjas, mandarinas, limones o pomelos, son muy sensibles a
hongos del género Phytophthora, que se encuentran presentes en casi todos los suelos.
Durante muchas décadas, el patrón naranjo amargo (Citrus aurantium L.) fue el estándar utilizado
en todas las plantaciones de cítricos de los países mediterráneos. Sin embargo, a partir de 1957, la
aparición del virus de la tristeza de los cítricos (CTV) obligó a la reconversión de la totalidad de nuestra
citricultura sobre patrones tolerantes a la enfermedad.
Los principales problemas que se presentan en la citricultura española, además del virus de la
tristeza, son: la clorosis férrica inducida en suelos calizos, la salinidad, la asfixia radical provocada por
inundaciones o por una capa freática alta, la escasez de agua, los decaimientos y muerte de árboles
ocasionados por hongos, principalmente del género Phytophthora, y los daños en las replantaciones
producidos por el nematodo de los cítricos
Unravelling Citrus Huanglongbing Disease
Get PDFHuanglongbing (HLB) or citrus greening is a disease caused by the unculturable, fastidious, phloem-restrictive, Gram-negative bacterium Candidatus Liberibacter spp. Currently, there are three species linked to the disease. The Asian form associated with Candidatus Liberibacter asiaticus (CLas) is heat-tolerant and can survive well above 30°C. The African (Candidatus Liberibacter africanus) and American forms are heat-sensitive and develop between 22 and 25°C (Candidatus Liberibacter americanus) (Bové, 2006). Huanglongbing is vector-transmitted mainly by the African citrus psyllid Trioza erytreae Del Guercio (Hemiptera: Triozidae) and the Asian citrus psyllid (ACP) Diaphorina citri Kuwayama (Hemiptera: Psyllidae), with two other psyllids also reported as vectors, D. communis Mathur and Cacopsilla citrisuga (Yang & Li) (Hemiptera: Pysllidae). The disease was first described in 1929 and reported in China in 1943. The African variation was reported in South Africa in 1947. The disease was reported in Brazil (São Paulo) in 2004 and the United States (Florida) in 2005. More than 20% of citrus trees in Brazil and 90% in Florida are currently affected, with symptomatic trees present in Texas and California. Huanglongbing is present and affects several citrus-producing countries of Asia, sub-Saharan Africa, and America (except for Bolivia, Chile, Perú, and Uruguay). The Mediterranean Basin and Australia are still free of HLB. The threat to HLB-free countries is constant due to the proximity of the disease and its vectors and the unstoppable increase in international trade
Physiological and Biochemical Responses to Salt Stress in Cultivated Eggplant (Solanum melongena L.) and in S. insanum L., a Close Wild Relative
Get PDFEggplant (Solanum melongena) has been described as moderately sensitive to salinity.
We characterised the responses to salt stress of eggplant and S. insanum, its putative wild ancestor.
Young plants of two accessions of both species were watered for 25 days with an irrigation solution
containing NaCl at concentrations of 0 (control), 50, 100, 200, and 300mM.Plant growth, photosynthetic
activity, concentrations of photosynthetic pigments, K+, Na+, and Cl ions, proline, total soluble
sugars, malondialdehyde, total phenolics, and total flavonoids, as well as superoxide dismutase,
catalase, and glutathione reductase specific activities, were quantified. Salt stress-induced reduction
of growth was greater in S. melongena than in S. insanum. The photosynthetic activity decreased in
both species, except for substomatal CO2 concentration (Ci) in S. insanum, although the photosynthetic
pigments were not degraded in the presence of NaCl. The levels of Na+ and Cl increased in roots
and leaves with increasing NaCl doses, but leaf K+ concentrations were maintained, indicating a
relative stress tolerance in the two accessions, which also did not seem to su er a remarkable degree
of salt-induced oxidative stress. Our results suggest that the higher salt tolerance of S. insanum mostly
lies in its ability to accumulate higher concentrations of proline and, to a lesser extent, Na+ and Cl.
The results obtained indicate that S. insanum is a good candidate for improving salt tolerance in
eggplant through breeding and introgression programmes
Aplicación de la oxifertirrigación para optimizar los recursos hídricos en cítricos, basado en la aplicación de peróxido de hidrógeno en el agua de riego
Get PDFEn este trabajo se estudia la respuesta fisiológica y agronómica de la aplicación de la
oxifertirrigación química, basada en la aplicación de peróxido de hidrógeno como fuente de
oxígeno a nivel radicular en cítricos. El ensayo tuvo lugar durante dos campañas (2018-2019
y 2019-2020) en árboles adultos de mandarino híbrido ‘Ortanique’ ubicados en una parcela
experimental del IMIDA en Torre Pacheco (Murcia). Se establecieron dos tratamientos, un
tratamiento ‘Control’ (0 ppm de H2O2) y otro identificado como ‘OXI’ (50-100 ppm de H2O2
durante todo el ciclo de cultivo). Ambos tratamientos recibieron la misma cantidad de agua y
de fertilizante. El H2O2 se aplicó de forma continua con una bomba dosificadora a la red de
riego. Los resultados más destacados mostraron que el estado hídrico de los árboles del
tratamiento ‘OXI’ fue muy similar al control. Respecto a los parámetros de intercambio
gaseoso, la aplicación de H2O2 estimuló una mayor apertura estomática en el mes de
septiembre de ambas campañas. Sin embargo, las ligeras alteraciones fisiológicas no han
supuesto cambios sustanciales en la biometría de la planta. En la segunda campaña, la
aplicación de H2O2 en el riego favoreció la acumulación de N, K y Fe en hoja, lo que permitiría
reducir la dosis de fertilizante. La respuesta productiva y la eficiencia en el uso del agua no
presentaron una clara mejora a la aplicación de H2O2 en el agua de riego. Los mayores niveles
de N en el tratamiento ‘OXI’ afectaron negativamente a la calidad del fruto, reduciendo el
porcentaje de zumo y aumentando el porcentaje de corteza. En cambio, la aplicación de H2O2
disminuyó el índice de madurez de la fruta, lo que resulta interesante de cara a retrasar la
recolección en variedades tardías
Effect of Sperm Concentration and Storage Temperature on Goat Spermatozoa during Liquid Storage
Get PDFOne of the problems with the refrigerated storage of spermatozoa in goats is the short shelf life. The study of the effect of the different storage conditions on the di erent sperm parameters could help to increase sperm survival. In this work, we studied the effect of temperature and sperm concentration during refrigerated storage on sperm motility, mitochondrial membrane potential and DNA fragmentation. We observed that refrigerated storage of semen doses reduced the majority of sperm quality parameters, however, sperm DNA fragmentation was not a ected. Storage at 5ºC preserved higher sperm motility than at 17ºC. Moreover, the reduction of sperm concentration below 500x10(6) sperm/mL did not seem to improve the quality of spermatozoa
Influence of New Citrus Rootstocks on Lemon Quality
Get PDFCitrus fruits are one of the main crops produced in the world with oranges, tangerines, lemons and grapefruits being among the most important. Among them, lemons are beneficial for human health because of their antioxidant activity, phenols and vitamin C. This study evaluates three rootstocks obtained in a Spanish breeding program (Valencian Institute for Agricultural Research (IVIA)): Forner-Alcaide 5 citrus rootstock (‘FA 5’), Forner-Alcaide 13 (‘FA 13’) and Forner-Alcaide 517 (‘FA 517’) grafted onto cultivars `Eureka´, `Verna´, `Fino 49’ and `Betera´. The results determined that rootstocks have influenced cultivars in terms of a decrease in the fruit size, weight, and thickness of the peel; but has increased the percentage of juice and soluble solids. With respect to phenol content and antioxidant activity, higher values were found with all cultivars studied on rootstocks ‘FA 13’, followed by ‘FA 517’. Cultivars that were most influenced by rootstocks were 'Bétera' and 'Eureka' in physical properties, while in chemical properties they were 'Verna' followed by 'Fino 49'. This investigation demonstrated the interaction of rootstocks on different cultivars in morphological, biochemical and nutraceutical characteristics
Rootstock Effect on Physico-Chemical and Nutritional Quality of Mandarin ‘Clemenules’ during the Harvest Season
Get PDFThis study reports the influence of eight rootstocks (‘Carrizo’ (CC), ‘C-35’ (C35) ‘Cleopatra’
(CL), ‘Volkameriana’ (VK), ‘Macrophylla’ (M), ‘Forner-Alcaide 5’ (FA5), ‘Forner-Alcaide 13’ (FA13)
and ‘Forner-Alcaide V17’ (V17)) on the physico-chemical and nutritional quality of ‘Clemenules’
mandarins at three harvest times during two seasons. Fruit quality parameters were influenced by
rootstocks, and this e ect was mostly harvest time -dependent. External color was overall influenced
by rootstocks upon the first harvest. FA13 and C35 induced a breakthrough in color change, while V17
brought about the greatest color increase. CL and V17 initially delayed the fruit maturity index. In the
last harvest, while CL had one of the highest maturity indices, V17 exhibited the lowest as acidity
was maintained as harvest advanced. The CC and M fruit had the highest and lowest sucrose content,
respectively. The highest glucose and fructose contents in fruit were induced by V17, FA5 and CC.
The highest citric acid content was displayed by V17 in all the harvests. The FA13, C35 and VK fruit
exhibited the highest malic acid content. The e ect that rootstock exert on ascorbic acid and flavonoid
content depends on the studied season. The results reveal the importance of conducting studies
during di erent seasons to obtain robust results