Sweet potato (Ipomoea batatas (L.) Lam.) is a major crop in Japan and worldwide. The sweet potato cultivar ‘Koganesengan’ is susceptible to damage by the southern root-knot nematode Meloidogyne incognita in Japan. We investigated the effects of cropping new resistant cultivars on the suppression of nematode population density and subsequent damage to the succeeding ‘Koganesengan’ crops. ‘Koganesengan’ was cropped with two resistant cultivars (‘Daichinoyume’ and ‘Konamizuki’). The tuberous roots of ‘Daichinoyume’ and ‘Konamizuki’ were seldom damaged, whereas ‘Koganesengan’ was heavily damaged. In the next spring, the nematode population density in the plow layer soil (10 cm-15 cm) was lower after ‘Daichinoyume’ and ‘Konamizuki’ cropping than after ‘Koganesengan’ cropping. Nematode damage to ‘Koganesengan’ tuberous roots after ‘Daichinoyume’ and ‘Konamizuki’ cropping was slightly suppressed compared to that after ‘Koganesengan’ cropping. Cropping of these cultivars is an effective method of suppressing nematode density and reducing damage to sweet potatoes. By clarifying the capability of resistant cultivars even overseas, it will be possible to use sweet potato as a nematode-suppressive crop.
There are about 170,000 irrigation ponds in Japan (May 2019) that serve a vital role as agricultural water resources in rural areas. However, these ponds are aging and the number of abandoned irrigation ponds has increased due to more farmland being abandoned and the aging of farmers. Many damaged irrigation ponds have been reported after heavy rains and earthquakes. During the past 10 years (2008-2017), 73% of all damaged irrigation ponds were damaged by heavy rainfall. About 64,000 ponds are specified as disaster-prevention-focused irrigation ponds (May 2019), which could pose a significant risk to downstream assets in case of a break. Thus, there has been rapidly growing social concern regarding disaster prevention and mitigation of the threat of such irrigation pond breaks. The prevention of irrigation pond failure due to heavy rain has consequently become a critical research topic. Accordingly, in this paper we review previous research on the damage to irrigation ponds due to heavy rain and the effects of various disaster prevention countermeasures relative to the following: 1) forms of damage and specific causes due to heavy rain; 2) flood analysis in case of a pond break, and flood control measures; and 3) methods of predicting potential damage due to an irrigation pond break.
We introduce the features of Common Agriculture Vocabulary (CAVOC) and CAVOC-based services, review other resources for standards in the domains of agriculture and food, and briefly discuss the future direction of agricultural semantics standards in Japan based on reviews. CAVOC has been developed as a core vocabulary for enhancing semantics-level interoperability. It specifies concepts that are frequently used to annotate agricultural data on agricultural activities and crops in Japan. The CAVOC website provides uniform resource identifiers by which the concepts in CAVOC are given. The data in CAVOC can be downloaded from the website. The extension of CAVOC coverage is important to unambiguously define objects and their relationships in the domains of agriculture and food. International collaborative efforts to create standards in agricultural semantics are underway through mapping among semantic resources within international projects and by holding meetings among stakeholders. We need to join the international community in creating agricultural semantics standards so as to extend CAVOC coverage through the utilization of foreign resources.
To compare the seed productivity of germplasm in India (Tamil Nadu) and Japan (Tsukuba), a total of 105 accessions from the Japanese National Agriculture and Food Research Organization (NARO) sorghum core collection were cultivated. The comparative cultivation studies were conducted at two locations in India and one in Japan. Differences in cultivation environments, including day length, temperature, and rainfall were evident in all the studies, and accordingly, seed production varied. The accessions grown in Japan yielded the highest number of grains per panicle. However, 11 accessions cultivated in Japan produced no harvest. Conversely, all accessions grown in parts of India, such as in Coimbatore, produced seeds. Therefore, although seed production in Japan was superior, there were benefits to cultivating the crops in India, including longer cultivation periods and the ability to overcome difficulties with seed multiplication found in Japan. Comparative cultivation projects involving international collaborative research are essential to reveal seed productivity in genetically diverse resources of sorghum. This study provides data about international sorghum production and information about differences in available accessions.
A total of 94 blast isolates were collected from five provinces in the Mekong River Delta in southern Vietnam. The pathogenicities of these isolates were evaluated using 25 international differential varieties (DVs) covering 23 resistance genes and a susceptible Chinese cultivar, Lijiangxintuanheigu (LTH). Based on the reaction patterns of the DVs, the isolates were classified into two clusters (I and II). Isolates virulent towards the DVs for Pit, Piz-t, Pi19(t), and Pita were more frequent in cluster I than in cluster II. Isolates virulent towards the DVs for Pi3, Pi5(t), and Pita-2 were more frequent in cluster II than in cluster I. Differences were also found in their geographical distributions, with isolates of cluster I dominant in the southern region of the Mekong River Delta and those of cluster II dominant in the northern region. Finally, the blast isolates were classified into 67 races. Based on these results and information on donor rice cultivars, the relationships between blast races and cultivated rice varieties were discussed. This information will be useful for understanding the variation of blast races distributed along the Mekong River in the countries of Southeast Asia.
Child health is often a weak link in developing countries, and Myanmar is a case in point. Broadly speaking, a mother’s education has been shown in the literature to be an important factor in the determination of child health. But the empowerment of women over the allocation of intrahousehold resources has also been shown to be an important child health factor, and thus an accumulation of human capital. In the present study, we use survey data on an important anthropometric indicator of child health and its associated household characteristics to specify and estimate a child-health production function in rural Myanmar. We then use this production function to draw implications for the height-for-age growth curves. Importantly, our questionnaire-based indicator of empowerment shows the mother’s influence over household decisions regarding income, expenditures, and education to be an important factor in the Z-score of the height-for-age indicative of a child’s longterm nutritional status. Nearly 30% of girls and 48% of boys are found in a condition of being stunted nutritionally, and the growth curves come closer to the WHO standard as the empowerment of women improves. Although a number of women rights were achieved early in Myanmar, greater empowerment in the home remains a key to improve child welfare.
Cowpea, also known as black-eyed pea, is one of the most promising foods for nutritional improvement for many African countries. Cowpea—including its seeds, young pods, and leaves—supplies essential nutrients, such as high-quality protein. It is also of vital importance to the livelihood of many people in West Africa as a cash crop. In August 2018, we conducted a survey on 206 households in rural villages in Yako and Po, located in northern and southern Burkina Faso, respectively. We compared the cowpea production at the family plot and women’s plot levels, and the usages of cowpea seeds, leaves and pods between these two climatically and culturally different regions. Cowpea production in family plots is quite popular in both regions, suggesting that cowpea should no longer be considered just a “women’s crop.” Different varieties of crops are sold in the south, whereas cowpea is a major cash crop in the north. Regarding cowpea usage, all households in the north consume not only cowpea seeds but also the young pods and leaves, whereas some households in the south only consume the seeds. No households in the north use cowpea as a baby food, despite its nutritious content when properly prepared. These findings suggest the need to promote further utilization of cowpea in different forms in order to maximize its potential.
Trichuris suis is a common parasite in pigs that is thought to infect humans based on studies using recently developed molecular methods. However, the utility of such molecular methods for detection has not been examined. In the present study, we assessed PCR- and sequencing-based molecular methods for the detection of several stages of T. suis. PCR targeting the mitochondrial large ribosomal subunit was successful with amplification of DNA from the samples. The sequences of the isolates formed a phylogenetic cluster with isolates from China and Ecuador. The assay was effective by using DNAs extracted from a low number of eggs (> 20 eggs) and the fragments of worms after histopathologic analyses. This is the first report describing the molecular identification of T. suis from pigs in Japan.
We verified the efficiency of poultry by-product meal (PBM) as a substitute for fish meal (FM) in feed for juvenile milkfish (Chanos chanos). Juveniles (mean 48.0 g) were fed for 12 weeks with two experimental feeds containing different levels of PBM (8.0% and 12%), FM (10% and 5.0%), and cod liver oil (fish oil or FO, 4.0% and 3.8%). A feed without PBM having higher levels of FM and FO (20% and 4.5%, respectively) was used as control. Weight gain, specific growth rate, and feed conversion ratio were not significantly affected by the levels of dietary PBM. In addition, no significant differences were detected among the dietary groups in plasma triglyceride, total cholesterol, phospholipid, glucose, or total protein concentrations. Furthermore, crude protein, crude fat, moisture, and ash contents in the whole body, liver, and dorsal muscle were not significantly influenced by the dietary treatments. The results of organoleptic examinations that included tests of smell, flavor, and texture were almost the same among the dietary groups. These results indicated that PBM is the applicable substitute for FM, with performance of the high PBM feed (PBM-FM-FO = 12%-5.0%-3.8%) being comparable to that of the control feed.