Showing papers in "Jarq-japan Agricultural Research Quarterly in 2020"
7 citations
6 citations
TL;DR: In this paper, a probit model and OLS regression analysis were used to estimate the likelihood of participation in contract farming and the impact of contract farming on rice farmers' income, respectively.
Abstract: This study aims to examine the revenue effects of rice contract farming for small high-value rice farmers and explore the constraints on the adoption of contract farming in China using a face-to-face survey questionnaire as the main instrument of data collection. A probit model and ordinary leastsquares (OLS) regression analysis were used to estimate the likelihood of participation in contract farming and the impact of contract farming on rice farmers’ income, respectively. A total of 78 household questionnaires collected in Wuchang was considered valid for analysis. This study proves that participating in contract farming is an effective way of increasing rice farmers’ income, after control for observable and unobservable household characteristics. Specifically, contract farming contributes toward enhancing the rice farm-gate price and cost-profit ratio. The results also reveal that rice farmers with organic or green planting experience are more likely to participate in contract farming. Discipline: Social Science Additional key words: contract farming, farm-gate price, rice farmers’ income, Wuchang rice
6 citations
TL;DR: Quantitative trait loci for leaf trichome density have been identified on LGs 5, 7, 8, and 15 of grapevine and applying information on these loci in breeding programs would allow the introduction of this natural physical barrier against pathogenic microorganisms into cultivars.
Abstract: Leaf trichomes confer pest resistance. Dense trichomes could also present a physical barrier to microorganisms, such as grapevine downy mildew caused by Plasmopara viticola on grape. Zoospores of P. viticola swim in water and enter stomata. Some wild Vitis accessions such as V. labrusca and V. cinerea have highly hydrophobic, dense, prostrate trichomes on the lower leaf surface that repel water and enhance resistance to downy mildew. Quantitative trait loci for leaf trichome density have been identified on LGs 5, 7, 8, and 15 of grapevine. A major locus on LG 5 was found in V. vinifera ‘Muscat of Alexandria,’ which has few leaf trichomes. Hairless alleles on LG 5 in historical V. vinifera cultivars reduce trichome density in the progeny of V. labrusca origin. Applying information on these loci in breeding programs would allow the introduction of this natural physical barrier against pathogenic microorganisms into cultivars. Discipline: Horticulture Additional key words: preexisting disease resistance, Plasmopara viticola, Vitis labrusca, Vitis vinifera
5 citations
TL;DR: Results suggest that HLB disease prefers citrus growing in alkaline soil where the concentrations of Fe and Zn nutrients are reduced, compared with the leaves from trees grown in acidic soil.
Abstract: An epidemiological investigation was conducted in the Amami Islands of Kagoshima Prefecture, Japan, to determine the pathogenesis of citrus greening disease, also known as citrus Huanglongbing (HLB) disease, especially in relation to trace metal nutrition. We sampled 11 sites with acidic soil and 46 sites with alkaline soil in private gardens on the islands of Tokunoshima and Amami Oshima. At the acidic sites, no HLB-infected citrus trees were detected using PCR amplification. In the private gardens, 38.6% of the trees tested were infected with HLB disease. By comparing soil pH values in those private gardens, we found that HLB infection was related to soil pH. Among trees growing in alkaline soil, 47.8% were infected, whereas none of the trees growing in acidic soil in the private gardens were infected. When comparing a distribution map of HLB-diseased trees with a soil component map of the five Amami Islands, HLB disease was not detected in acidic soil, but the distribution of HLB-diseased trees was similar to the location of alkaline soil. Microelement analysis of leaves from trees grown in alkaline soil revealed significantly lower levels of manganese (71.9%), copper (70.1%), zinc (52.3%), and iron (40.9%) compared with the leaves from trees grown in acidic soil. These results suggest that HLB disease prefers citrus growing in alkaline soil where the concentrations of Fe and Zn nutrients are reduced. Discipline: Agricultural Environment Additional key words: acidic soil, citrus greening disease, iron, micronutrient, PCR Does HLB Disease Prefer Citrus Growing in Alkaline Soil?
5 citations
4 citations
4 citations
TL;DR: In this paper, the authors conducted a survey on 206 households in rural villages in Yako and Po, located in northern and southern Burkina Faso, respectively, and compared the cowpea production at the family plot and women's plot levels, and the usages of cow pea seeds, leaves and pods between these two climatically and culturally different regions.
Abstract: 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. Discipline: Social Science Additional key words: regional difference, women’s role
4 citations
TL;DR: The production process of such traditional Japanese fermented foods as miso, shoyu and sake using Aspergillus oryzae has been highly optimized over a long history, but new technology is needed to achieve further improvements in productivity or production efficiency.
Abstract: The production process of such traditional Japanese fermented foods as miso, shoyu and sake using Aspergillus oryzae has been highly optimized over a long history. However, new technology is needed to achieve further improvements in productivity or production efficiency. Light affects the gene expression and metabolic pathways of fungi. Thus, the development of technology that takes advantage of the light response of A. oryzae is important. In a previous study, we found that A. oryzae strains RIB40 and RIB1187 showed opposing manners of growth and conidiation in response to light. To elucidate the effect of light on genome-wide gene expression for both strains, we conducted transcriptome analysis by RNA sequencing. We also identified 453 differentially expressed genes (DEGs) between both strains by bioinformatic analysis. Of these 453 DEGs, we identified a total of 67 light-responsive DEGs between RIB40 and RIB1187. We also analyzed the expression patterns of fermentation-related digestive enzyme genes. Discipline: Biotechnology Additional key words: RNA sequence, gene expression, koji fermentation Transcriptome of Aspergillus oryzae Responding to Light
4 citations
TL;DR: The Japanese Black embryo-transfer calves began to suckle larger amounts of milk from their surrogate dams and showed rapid growth that was comparable to that of larger framed Japanese Shorthorn calves.
Abstract: The growth characteristics of five male Japanese Black calves that were produced by embryo transfer to, born from, and nursed by Japanese Shorthorn surrogate dams (BS-group) were compared with those of five male Japanese Shorthorn calves that were delivered from dams of the same breed after natural mating (SS-group). The birth weights of the BS-group calves were lower (P < 0.01) than those of the SS-group calves. During the first two months, the daily weight gain of the SS-group calves was greater (P < 0.05) than that of the BS-group calves. However, between the third and fourth months, the daily weight gain of the BS-group calves was greater (P > 0.05). During the first two months, the chest girth was smaller (P < 0.05) in the BS-group calves than in the SS-group calves, but was similar in both groups by the age of four months. Although the gains in chest depth, body length, and withers height of the BS-group calves were inferior to those of the SS-group calves during the first two months, these gains were all superior to those of the SS-group calves during the next two months. Trends in age-related changes in plasma total cholesterol concentrations significantly differed between both groups. The SS-group dams lost much more weight during early lactation than did the BS-group dams (P > 0.05). No difference was observed in the blood components of the dams in either group. In summary, the BS-group calves were relatively small at birth, and their growth performance was inferior to that of the SS-group calves during the first two months. At around two months of age, the Japanese Black embryo-transfer calves began to suckle larger amounts of milk from their surrogate dams and showed rapid growth that was comparable to that of larger framed Japanese Shorthorn calves. Discipline: Animal Science Additional key words: cow-calf grazing, Japanese Black cattle, lactation, Wagyu, weight gain *Corresponding author: e-mail guchi@affrc.go.jp Received 10 August 2018; accepted 21 May 2019. Comparison on Growth between Two Different Japanese Beef Calves
3 citations
TL;DR: The research activities to develop and validate new analytical methods for recently distributed GM crops are reviewed, including real-time PCR-based quantitative methods for two GM maize events, and the group testing method is developed.
Abstract: The varieties of commercially available genetically modified (GM) crops are rapidly increasing, and this situation demands analytical methods capable of detecting recently developed GM crops. Here we review our research activities to develop and validate new analytical methods for recently distributed GM crops. For the screening analysis of GM content in analytical samples, we developed real-time PCR-based quantitative methods for two GM maize events, MIR604 and MIR162. To accurately analyze GM content irrespective of the commingling of stacked GM events, we developed the group testing method. For the comprehensive analysis of various GM events, the real-time PCR array method was established. In November 2016, the Consumer Affairs Agency of Japan released the standard testing manual including these new testing methods to ensure the validity of the food labeling system in Japan. Given the expected increase in the number of GM events to be analyzed in the future, we need to keep working toward the realization of simple and comprehensive detection and quantification methods that can be used for the increasing number of these events. Discipline: Food Additional key words: GM crop, GMO, detection, standard testing method
TL;DR: In this paper, stable isotope ratios of carbon (δ 13C) and nitrogen(δ 15N) were determined for the spotted scat (Scatophagus argus) in the Matang Mangrove Forest Reserve in Peninsular Malaysia, indicating that S. argus utilizes various food items between the coastal area at the river mouth to the inner mangrove estuary.
Abstract: Stable isotope ratios of carbon (δ 13C) and nitrogen (δ 15N) were determined for the spotted scat (Scatophagus argus) in the Matang Mangrove Forest Reserve in Peninsular Malaysia. The ratios from fish samples along with those obtained from samples of their potential food items (i.e., mangrove leaves in the estuary, coastal phytoplankton, microphytobenthos) revealed wide variations, indicating that S. argus utilizes various food items between the coastal area at the river mouth to the inner mangrove estuary. The carbon isotope ratio in the fish body tended to be lower in fish sampled from the inner estuary as compared with fish at the river mouth. The carbon isotope ratio values of the fish body were relatively high in small fish (<20 mm in total length [TL]) but lower in fish of 20-100 mm TL, and relatively higher in fish >100 mm TL. These findings strongly suggest that small-sized S. argus (<20 mm TL) migrate from the outer coastal area into the mangrove estuary and utilize the mangrove estuary habitat as their nursery grounds before eventually returning to the river-mouth area as their growth progresses. Discipline: Fisheries Additional key words: stable carbon/nitrogen isotope ratios, mangrove estuary, fish nursery ground, migration
TL;DR: Results suggest that CTVfree yuzu production is possible in the Rikuzen-Takata and Ofunato areas of Japan, and suggest that the conditions in those areas make it difficult to control the citrus tristeza.
Abstract: Citrus tristeza virus (CTV) commonly infects yuzu (Citrus junos) in most parts of the citrus-growing areas in Japan. This study examined the occurrence of CTV in the northernmost commercial citrusproducing areas of Japan. Colonies of the brown citrus aphid (Toxoptera citricidus) were detected within the areas investigated. However, 23 of the 41 trees that were examined by RT-PCR and both or either subject to stem-pitting observation and immunostrip testing were free of CTV. Several CTVfree trees were apparently more than 60 years old. A field trial revealed that all eight uninoculated seedlings tested negative for CTV at 52 months after transplanting. These results suggest that CTVfree yuzu production is possible in the Rikuzen-Takata and Ofunato areas of Japan. Discipline: Agricultural Environment Additional key words: Citrus junos Sieb. ex Tanaka, Great East Japan Earthquake, Toxoptera citricidus Introduction Yuzu (Citrus junos Sieb. ex Tanaka) is a cold-hardy sour citrus species that can grow in northern areas (Kawase et al. 1983). The yuzu fruit is very popular due to its characteristic flavor and is widely used as a dressing in Japanese cuisine (Miyazawa et al. 2009). The northernmost commercial yuzu-producing areas in Japan overlap with the main apple-growing regions. Specifically, yuzu has been grown for many years in the Rikuzen-Takata and Ofunato areas in Iwate Prefecture (around 39°N and 142°E) (Fig. 1), primarily for ornamental purposes and production of the fruit, which is mainly consumed by the families of local farmers. However, in response to the recent increase in the popularity of yuzu, farmers in the Rikuzen-Takata and Ofunato areas have considered increasing the commercial production of yuzu, with potential financial benefits for these yuzu-producing areas. Yuzu is highly susceptible to citrus tristeza virus (CTV), which commonly infects citrus species (Moreno et al. 2008, Dawson et al. 2015, Harper & Cowell 2016). Yuzu trees infected by CTV grow poorly and often produce relatively small fruits with blemished skin (Ieki 2003). Many yuzu trees in the southern yuzu-producing areas of Japan are affected by tristeza. In Japan, CTV is mainly transmitted by the brown citrus aphid (Toxoptera citricidus) commonly found in the southern yuzuproducing areas (Ieki 2003). The conditions in those areas make it difficult to control the citrus tristeza *Corresponding author: ti207181@nodai.ac.jp Received 19 November 2019; accepted 27 February 2020. 307 JARQ 54 (4), 307-316 (2020) https://www.jircas.go.jp
TL;DR: Differences were found in the relationships between blast races and cultivated rice varieties, with isolates of cluster I dominant in the southern region of the Mekong River Delta and those of cluster II dominate in the northern region.
Abstract: 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. Discipline: Agricultural Environment Additional key words: variation, race, rice (Oryza sativa L.), differential system
TL;DR: In this article, the authors assessed the stand structure and estimated the total stem volume of a 30-year-old Eucalyptus globulus forest in the highlands (>3000 m altitude) of northern Ethiopia.
Abstract: The development of forest monitoring methods for the plantation eucalypt forests in Ethiopia is crucial as eucalypts play an important role in the country’s wood supply. We assessed the stand structure and estimated the total stem volume of a 30-year-old Eucalyptus globulus forest in the highlands (>3000 m altitude) of northern Ethiopia. Census data were collected from 186 trees, of which 28 trees were destructively sampled. The forest stand density was 581 trees ha −1, mean ± SD diameter at breast height was 21.2 ± 6.4 cm, and mean ± SD predicted tree height was 22.0 ± 4.2 m. The estimated stem volume was 269.7 m 3 ha −1. An allometric model to predict tree height was derived using the measured diameter at breast height of the sampled trees. Moreover, an allometric model was developed to estimate stem volume for standing trees in order to describe the relationship between the stem volume and diameter at breast height squared × tree height (incorporated as a compound variable), using data on 38 trees for which height could be measured reliably. The findings suggest that the diameter at breast height alone can be used to estimate stem volume, and thus may be useful for simple forest monitoring in the study region. This study is one of the few to assess the stand structure and stem volume of a high-altitude Eucalyptus plantation. Discipline: Forestry Additional key words: allometry, Bahr-Zaf, forest monitoring, high altitude
TL;DR: In this paper, a time series of Normalized Difference Vegetation Index (NDVI) data from 1983 to 2013, derived from the Advanced Very High-Resolution Radiometer-Vegetation Health Product (AVHRR-VHP), was applied to detect linear trends, seasonal phenology transition dates, and growing seasons.
Abstract: To assess the dynamics of vegetation growth and phenology in the Inner Mongolia Autonomous Region in China, a time series of Normalized Difference Vegetation Index (NDVI) data from 1983 to 2013, derived from the Advanced Very High-Resolution Radiometer-Vegetation Health Product (AVHRR-VHP), was applied to detect linear trends, seasonal phenology transition dates, and growing seasons. Overall, Inner Mongolia became warmer and drier during the study period. A significant increasing cumulative NDVI trend was found for 30.30% of the total vegetation covered area. The restored area was mainly in the western desert steppe. The degraded area was primarily located in the northeastern meadow and typical steppe regions. However, a severe drought was detected during 1993-2003, when approximately 27.56% of the total vegetation covered area experienced a significant decreasing NDVI trend. The length of the growing season (LOS) during 1983-2013 was shortened due to the delayed start of the growing season (SOS) and advanced timing of the end of the growing season (EOS). However, this trend was reversed during the more recent decade (2003-2013). The phenology was closely associated with climate change, especially precipitation. The variability of vegetation responses to climate change was also assessed, indicating that most types of vegetation had recently recovered and that the restored areas had a varied spatial distribution. Discipline: Animal Science Additional key words: cumulative annual NDVI, heterogenous distribution, land degradation, vegetation recovery *Corresponding author: e-mail kamuken@affrc.go.jp Received 5 November 2018; accepted 25 June 2019. Vegetation Dynamics in Inner Mongolia
TL;DR: In this article, the authors examined the biomass and production rates of fine roots at soil depths of 0 cm-40 cm in Avicennia alba and Rhizophora apiculata stands in Ranong Province, southern Thailand.
Abstract: Fine roots are a key component of belowground carbon dynamics in forest ecosystems. However, information on fine root dynamics in mangrove forests is still limited. Therefore, in this study we examined the biomass and production rates of fine roots by using soil coring and an ingrowth core method, respectively, at soil depths of 0 cm-40 cm in Avicennia alba and Rhizophora apiculata stands in Ranong Province, southern Thailand. In these stands, the fine root biomass was ca. 3.4 kg m−2 and 1.4 kg m−2, respectively, while fine root production rates were ca. 450 g m−2 year−1 and 740 g m−2 year−1, respectively. Fine root biomass was not significantly different between the surface (0 cm20 cm) and subsurface (20 cm-40 cm) soil in both stands. The fine root production rate was also similar between the soil layers in the R. apiculata stand, whereas it decreased with soil depth in the A. alba stand. The patterns of vertical distribution of fine root production rates probably reflected the species characteristics of A. alba and R. apiculata, and suggested that fine root production in the subsurface soil contributes significantly to belowground carbon dynamics, especially in R. apiculata. Discipline: Forestry Additional key words: Avicennia alba, ingrowth core, Rhizophora apiculata, soil depth, vertical distribution
TL;DR: Improvement of general hygiene control and the use of starter culture are considered necessary to prevent foodborne illnesses caused by B. cereus in fermented soybean produced in these countries.
Abstract: Fermented soybeans without salt (“Tua Nao”) are commonly produced and consumed in northern areas of Lao PDR and Thailand. Contamination of pathogenic Bacillus (B.) cereus during its production may cause toxic food poisoning. To evaluate the practical risk, we purchased 10 Lao and 23 Thai Tua Nao products from local markets in the northern areas of both countries, and then confirmed B. cereus contamination. Nine (90%) of the 10 Lao samples and 18 (78%) of the 23 Thai samples contained B. cereus. Two of the Thai isolates produced diarrheal enterotoxin confirmed by a reversed passive latex agglutination test (an immunological method). Emetic toxin coding gene (crs) was detected from two Lao isolates by the PCR method. These five (potential) toxin-producing B. cereus strains exhibited different random amplified polymorphic DNA (RAPD)-PCR patterns. Improvement of general hygiene control and the use of starter culture are considered necessary to prevent foodborne illnesses caused by B. cereus in fermented soybean produced in these countries. Discipline: Food Additional key words: food poisoning, RAPD-PCR *Corresponding author: e-mail inatu@affrc.go.jp Received 12 February 2019; accepted 7 May 2019.
TL;DR: In this article, an accelerometry-based activity monitor, the Kenz Lifecorder EX (hereafter, the LC), was used to differentiate between foraging and other activities of cows.
Abstract: Livestock select places in a pasture that offer high-quality and nutritious grass, and these selections cause spatial heterogeneity and reduced productivity. To maximize the efficiency of pasture systems, it is important to understand the spatiotemporal information regarding livestock grazing behavior. In this review, we describe studies conducted to develop a simple tool for determining cow foraging behavior, and to predict the spatial distribution of cow excrement (dung) in a steeply sloping pasture. An accelerometry-based activity monitor, the Kenz Lifecorder EX (hereafter, the LC), was used to differentiate between foraging and other activities of beef cows. A linear discriminant analysis yielded good discrimination accuracy of the minute-based data of the LC. The combination of the activity timeline and GPS tracking data successfully revealed the spatiotemporal distribution of cow foraging activity in a sloping pasture. Both foraging activity and excretion play important roles in the nutrient cycling in pasture ecosystems. We found that the spatial distribution of cow dung could be predicted using a Bayesian approach in conjunction with a generalized linear mixed model incorporating conditional autoregressive terms with two parameters (green herbage biomass and distance from a water trough). Dung deposits tended to be distributed in areas with higher green herbage biomass and in areas located closer to the water trough. We also describe a new pasture survey method of detecting cow dung and weed positions in a pasture by using unmanned aerial vehicle (UAV)-based imagery. Discipline: Animal Science Additional key words: accelerometer, cattle, dung, UAV
TL;DR: In this paper, Zhao et al. used zymography to observe the enzymes in the liquefaction process of Khanom jeen noodles and found an increase in reducing sugar, presumably derived from oligosaccharides by starch digestion in the noodles.
Abstract: Khanom jeen is a traditional Thai noodle made from fermented rice flour. It is produced and consumed throughout Thailand. Noodle products in local markets usually maintain their quality without rotting for a few days at ambient temperature. However, producers occasionally suffer the problem of noodle liquefaction. Severe liquefaction occurs unpredictably within a day at the production site. In the present study, liquefaction was induced by treating noodles with McIlvaine buffer at pH 6.0 and pH 8.0, but was not induced when the noodles were treated with distilled water, McIlvaine buffers at pH 4.0, or 1% sodium lactate buffer at pH 4.0. This pH-induced liquefaction was suppressed when chloramphenicol was added to the buffers, suggesting that this phenomenon was associated with bacterial growth. An increase in reducing sugar, presumably derived from oligosaccharides by starch digestion in the noodles, was observed in accordance with α-amylase production under the liquefaction-inducing conditions. Different starch-digesting enzymes in the liquefaction process were observed using zymography. The noodles used in this study contained about 0.03% lactic acid. Maintaining the acidic environment in noodles to prevent bacterial digestion of starch should help retain the khanom jeen noodle structure. Discipline: Food Additional key words: pH adjustment, starch *Corresponding author: e-mail jmarui@affrc.go.jp Received 28 November 2018; accepted 5 April 2019.
TL;DR: In this paper, the authors reviewed 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 the heavy rain; 2) flood analysis in case of a pond break, and 3) methods of predicting potential damage due to an irrigation pond break.
Abstract: 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. Discipline: Agricultural Engineering Additional key words: causes of irrigation pond damage, f lood analysis, f lood control, forms of irrigation pond damage, irrigation pond break *Corresponding author: e-mail is585@affrc.go.jp Received 9 April 2019; accepted 12 November 2019.
TL;DR: A review of recent studies on how modification to light quality influences the production of these crops is presented in this article, where light conditions are increasingly being modified with such artificial light as light-emitting diodes (LEDs), coupled with sheet mulching.
Abstract: Light is one of the most important factors affecting plant growth. Although photosynthesis has been widely investigated, knowledge remains limited on how the quality of light influences the production of horticultural crops, especially fruits and vegetables. Here, we present a review of recent studies on how modification to light quality influences the production of these crops. The light environment contributes toward sustaining and regulating fruit and vegetable production. And light conditions are increasingly being modified with such artificial light as light-emitting diodes (LEDs), coupled with sheet mulching. These tools are useful for enhancing light-mediated growth and reproduction in plants. Thus, the physiological and biological responses of plants to light must be analyzed to advance our understanding of the molecular mechanisms underlying how light controls plant development. Discipline: Horticulture Additional key words: environment, growth, LEDs, mulch sheet, reflection, ultraviolet (UV)
TL;DR: Some of the transgenic progeny exhibited blue flower colors and contained modified anthocyanins, like their transgenic parents, and suggested that the risk of transgenes escaping to wild species could be quite high.
Abstract: Transgenic chrysanthemums (Chrysanthemum morifolium) with blue flower colors have already been created, and are expected to be commercialized. However, cultivated chrysanthemums are known to cross with wild species native to Japan, and careful studies are needed to assess the risk of these transgenes escaping into wild Chrysanthemum populations. We previously reported on the transmission of transgenes from the model cultivar ‘Taihei’ to interspecific progeny. For this study, we used the recently developed cultivar ‘Sei Arabella’ and a promising breeding strain (T37) as transgene hosts, and performed crosses between these lines and the wild species Chrysanthemum japonense var. japonense. We found relatively high seed set rates (20.6%-83.4%) after artificial, reciprocal pollinations, and the inheritance and segregation of the transgenes in the hybrid progeny were confirmed by PCR. Some of the transgenic progeny exhibited blue flower colors and contained modified anthocyanins, like their transgenic parents. These results were similar to those obtained with ‘Taihei’ and thus suggested that the risk of transgenes escaping to wild species could be quite high. Therefore, it will be important to investigate techniques to reduce this risk. Discipline: Horticulture Additional key words: environmental risk, flower color, ornamental plants, transformation
TL;DR: The results indicate that L. multiflorum has developed resistance to glyphosate and glufosinate in the orchards, and suggest that the foliar application of quizalofop-ethyl is particularly effective for the control of this weed.
Abstract: In this study, we aimed to evaluate the levels of resistance of Lolium multiflorum populations to glyphosate and glufosinate in Japanese pear orchards in Hamamatsu City, Shizuoka Prefecture, Japan, and determine the efficacy of several foliar-applied herbicides to control this weed during several growth stages. Bioassays using glyphosate-potassium (1.08-2.70 kg ai ha -1) and glufosinate (0.60-1.00 kg ai ha -1) were conducted, and the survival rates of L. multiflorum populations after foliar application were 11.1%-53.3% and 0.0%-5.6%, respectively. After treatments with several foliarapplied herbicides in the early growth stage (at a plant length of about 5 cm) with the maximum dosage, the survival rate of plants treated with glyphosate-potassium (38.9%) was not significantly different from that of plants receiving no treatment (100%). However, the survival rates of plants treated with quizalofop-ethyl (0.0%), glufosinate (17.8%), and glufosinate-P-sodium (18.9%) were significantly lower than that of plants receiving no treatment. In the middle growth stage (at a plant length of about 35 cm), although the survival rate of plants treated with quizalofop-ethyl (8.3%) was significantly lower than that of plants receiving no treatment (100%), the survival rates of other plants were not significantly different from that of plants receiving no treatment. These results indicate that L. multiflorum has developed resistance to glyphosate and glufosinate in the orchards, and suggest that the foliar application of quizalofop-ethyl (0.74 kg ai ha -1) is particularly effective for the control of this weed. Discipline: Crop Science Additional key words: glyphosate, glufosinate, herbicide resistance, Japanese pear orchard, Lolium multiflorum