To stay or re-migrate after the pandemic shock? Labor re-migration intention to the coastal areas of Thua Thiên Hue province in Vietnam.

This study applied the extended theory of planned behavior (ETPB) to explore factors that shape the behavioral intention of migrant laborers returning to the coastal region of Thua Thiên Hue province during the peak of the COVID-19 pandemic to remigrate. Data collection included 210 interviews with returned migrants aged 18 and above in 4 coastal communes of Thua Thiên Hue province, in-depth interviews (8 key informants) and a group discussion (5 persons). Exploratory factor analysis and a multivariate linear regression model were applied to analyze the data. Results showed that in addition to individual socio-demographic characteristics (i.e. level of education, age, income level and sex), attitudes, subjective norms, perceived behavioral control, and perceived risk were also determinant factors of migrants' intention to remigrate. This research suggested that in order to build resilience of rural migration workers, related departments should seriously consider the following recommendations: (i) raise awareness and encourage young rural people to complete their education and necessary skills; (ii) organize related psychological training programs for rural laborers; (iii) raise awareness about the necessity to participate in social insurance; (iv) promote rural job creation programs suitable for low education and low-skilled rural laborers; (v) raise awareness for local people, particularly school children, about the value and opportunities of being smart farmers in the context of 4.0 technology and social risks at the destination for low education and low-skilled laborers; (vi) digitalize migration labor management and provide digital information services regarding job opportunities for rural laborers.

Evidence of Sexual Reproduction Events in the Dagger Nematode Xiphinema index in Grapevine Resistance Experiments Under Controlled Conditions.

The dagger nematode Xiphinema index has a major economic impact because of its transmission of Grapevine fanleaf virus to grapevines. This vector nematode, which was introduced into Western countries from the Middle East together with the domesticated grapevine, mostly reproduces by meiotic parthenogenesis, but microsatellite multilocus genotype (MLG) analysis has revealed the occurrence of rare sexual reproduction events in field conditions. In a previous 6-year study under controlled conditions, we evaluated the durability of resistance to X. index in accessions derived from a muscadine resistance source and reference accessions. In this previous study, we used an equal-proportion mixture of four lines (from Spain, Italy, Greece, and Iran) representative of X. index diversity as the inoculum, and we collected random samples in 3-, 4-, 5-, and 6-year-old vines. Here, we genotyped the individuals from these samples using the MLG technique, and we analyzed the changes in line frequency and the occurrence of sexual reproduction events between lines over time. The nematode lines differed in aggressiveness and hybrids between lines were detected at a low, but apparently increasing rate. Hybridization events were recovered in all accessions, regardless of resistance status and propagation type. Finally, our data provide the first evidence of sexual reproduction in the nematode X. index under controlled conditions.

Grapevine Resistance to the Nematode Xiphinema index Is Durable in Muscadine-Derived Plants Obtained from Hardwood Cuttings but Not from In Vitro.

Breeding for varieties carrying natural resistance (R) against plant-parasitic nematodes is a promising alternative to nematicide ban. In perennial crops, the long plant-nematode interaction increases the risk for R breaking and R durability is a real challenge. In grapevine, the nematode Xiphinema index has a high economic impact by transmitting Grapevine fanleaf virus (GFLV) and, to delay GFLV transmission, rootstocks resistant to this vector are being selected, using Muscadinia rotundifolia in particular as an R source. To optimize in fine this strategy, the durability has been studied under controlled conditions in F1 and BC1 muscadine-derived resistant accessions previously obtained from either hardwood-cutting or in vitro propagation. After inoculation with a mix, in equal proportions, of four lines representative of the X. index diversity, multiplication on plants has been monitored 3 to 6 years. The nematode reproduction factor remained lower than 1 in resistant plants obtained from hardwood cuttings while it increased at values far beyond 1 in resistant plants of in vitro origin. Data for nematode numbers per gram of roots mostly paralleled those obtained for the reproduction factor. The effect of the propagation type on resistance over years was also evaluated for the ratio female/juvenile and the frequency of males. Altogether our results illustrate that the muscadine-derived resistance based on hardwood cuttings is durable. By contrast, in resistant and reference accessions obtained from in vitro, our data suggest that the increased nematode multiplication might be mainly due to the modification of root architecture consecutive to this propagation method.

Phylogeography of the soil-borne vector nematode Xiphinema index highly suggests Eastern origin and dissemination with domesticated grapevine.

The soil-borne nematode Xiphinema index is closely linked to its main host, the grapevine, and presents a major threat to vineyards worldwide due to its ability to transmit Grapevine fanleaf virus (GFLV). The phylogeography of X. index has been studied using mitochondrial and microsatellite markers in samples from most regions of its worldwide distribution to reveal its genetic diversity. We first used the mitochondrial marker CytB and illustrated the low intraspecific divergence of this mainly meiotic parthenogenetic species. To generate a higher polymorphism level, we then concatenated the sequences of CytB and three mitochondrial markers, ATP6, CO1 and ND4, to obtain a 3044-bp fragment. We differentiated two clades, which each contained two well-supported subclades. Samples from the eastern Mediterranean and the Near and Middle East were grouped into three of these subclades, whereas the samples from the western Mediterranean, Europe and the Americas all belonged to the fourth subclade. The highest polymorphism level was found in the samples of one of the Middle and Near East subclades, strongly suggesting that this region contained the native area of the nematode. An east-to-west nematode dissemination hypothesis appeared to match the routes of the domesticated grapevine during Antiquity, presumably mainly dispersed by the Greeks and the Romans. Surprisingly, the samples of the western subclade comprised only two highly similar mitochondrial haplotypes. The first haplotype, from southern Iberian Peninsula, Bordeaux and Provence vineyards, exhibited a high microsatellite polymorphism level that suggests introductions dating from Antiquity. The second haplotype contained a highly predominant microsatellite genotype widespread in distant western countries that may be a consequence of the massive grapevine replanting following the 19th-century phylloxera crisis. Finally, our study enabled us to draw a first scaffold of X. index diversity at the global scale.