Innovative agricultural extension value chain-based models for smallholder African farmers

The value chain extension strategy of Sasakawa Africa Association focuses on improving the capacity of national agricultural extension systems and follows various thematic areas along the value chain to address key challenges accountable for low income households and poverty in Africa. Farmer learning platform is a model designed to increase crop productivity and encompasses demonstration plots where technological packages demonstrated significantly outperformed other technology plots in crop productivity and average profit margins. Enterprise-oriented production, postharvest and trading centers are value adding models designed to improve the effectiveness of extension and adoption of postharvest and agricultural processing technologies by producers. The use of the above along with necessary capacity building has facilitated the development of profitable business linkages of smallholder farmers with financial institutions and reliable market opportunities. The community association trader-trainer model is a market-oriented business approach applied in combination with other extension models. In 2018, 297 community-based commodity association trader-trainers were mobilized and capacitated to improve farmer group dynamics and developed collective input and output access and cluster aggregation centers at community level where various agricultural produces were mobilized and collectively aggregated, and valued at about 3.9 million USD. The supervised enterprise project model is an innovative agricultural extension model developed along with above models for capacity development of extension agents and transfer of technologies to smallholder farmers. Over 6000 supervised enterprise projects have been introduced into 27 universities in 12 African countries for training front-line extension officers and extension delivery to farming communities.     

Quantitation of curcuminoids in curcuma rhizome by near-infrared spectroscopic analysis

This study investigated a nondestructive and rapid quantitation method for the curcuminoids, including curcumin, demethoxycurcumin, and bisdemethoxycurcumin, present in turmeric using near-infrared (NIR) spectroscopy and multivariate statistics. In the second derivatives of the NIR spectra of turmeric samples, two characteristic absorptions of curcuminoids were detected around 1700 and 2300-2320 nm. Partial least-squares regression (PLS-R) analysis was applied to the NIR spectra obtained from 34 turmeric samples, and PLS models for the quantitation of curcumin, demethoxycurcumin, bisdemethoxycurcumin, and total curcuminoid contents in the pulverized turmeric samples were constructed. Combination usage of the Standard Normal Variate (SNV) and second derivatives was obviously superior to other preprocessing methods. The lowest root mean squared error of cross-validation (RMSECV) values were detected at 6, 6, 6, and 6 PLS factors, for the quantitative subjects curcumin, demethoxycurcumin, bisdemethoxycurcumin, and total curcuminoid contents. It was clarified that the prediction of the composition by PLS-R analysis showed high correlation with the results of HPLC quantitations.     

Glycosylation of flagellin from Pseudomonas syringae pv. tabaci 6605 contributes to evasion of host tobacco plant surveillance system

Pseudomonas syringae pv. tabaci (Pta) possesses a genetic region composed of two open reading frames (ORFs), fgt1 and fgt2, that are involved in glycosylation of flagellin. The deletion mutant Δfgt1 produced non-glycosylated flagellin, and exhibited reduced ability to cause disease in the host tobacco plant. Flagellin is known to induce plant defense responses, and the recognition of flagellin by Arabidopsis thaliana is mediated by a conserved N-terminal region, flg22, in flagellin and a leucine-rich repeat domain in the FLS2 receptor. Because flg22 localizes inside the flagellum, polymerized flagellum needs to be dissociated to be recognized. Therefore, the effect of glycosylation on flagella stability was investigated. The polymerized flagella from glycosylated flagellins were more resistant to heat treatment than those from non-glycosylated flagellins, suggesting that the glycosylation of flagellin contributes to the structural stability of flagella and prevents exposure of the flg22 region. Polymerized flagella from Pta Δfgt1 flagellin and depolymerized and glycosylated flagellin from Pta wild type induced cell death and callose deposition, and inhibited seedling growth in tobacco more effectively, whereas polymerized flagella from Pta wild-type flagellin caused a low level of these responses. These results suggest Pta might have evolved the flagellin glycosylation system to evade detection and defense response of a host by increasing flagella stability and suppressing their dissociation.     

Polyphosphate kinase is essential for swarming motility, tolerance to environmental stresses, and virulence in Pseudomonas syringae pv. tabaci 6605

Polyphosphate kinase (PPK), encoded by the ppk gene, is a principal enzyme responsible for synthesis of inorganic polyphosphate (poly P) from ATP in many Gram-negative bacteria. In order to elucidate the functions of poly P in Pseudomonas syringae pv. tabaci 6605, an in-frame deletion mutant of the ppk gene (ppk) was constructed. The ppk mutant did not accumulate poly P, whereas the wild-type strain accumulated a large quantity. The mutant had reduced swarming motility, even though it retains swimming motility like the parental strain. The mutant exhibited increased sensitivity to prolonged incubation and environmental stresses, such as heat shock and oxidative stress and reduced exopolysaccharide (EPS) production compared to the wild-type. Northern blot analysis revealed that expression of the rpoS gene, encoding the stationary phase sigma factor RpoS, was reduced in ppk in the logarithmic phase, indicating that rpoS is regulated by the ppk gene. The poly P deficient mutant had significantly reduced ability to cause disease in its host tobacco plant and in planta growth of the mutant was also significantly reduced in host tobacco leaves as compared to the wild-type strain. Thus, our results suggest that poly P plays an important role in the virulence of P. syringae pv. tabaci 6605.     

A Hepatocellular Adenoma in a Diet-induced Obese Mouse

A hepatic nodule was noted in a C57BL/6J mouse with diet-induced obesity at 53 weeks of age. Macroscopically, a protruding yellowish white nodule was observed on the visceral surface of the left lateral lobe. Light microscopy demonstrated clear demarcation from the compressed adjacent parenchyma, with loss of the distinct lobular pattern. The proliferating cells of the lesion varied in shape and showed cellular atypia and prominent nucleoli along with vacuoles of various sizes. Some of the cells contained various-sized eosinophilic inclusion bodies in their cytoplasm, and electron microscopy revealed the presence of lipid droplets in the rough endoplasmic reticulum. Eosinophilic inclusions were observed as electron dense granular material in the rough endoplasmic reticulum, with one or a few low density central cores. A diagnosis of hepatocellular adenoma was made based on these findings.     

Evaluation of Short-term Myelotoxicity Study in Dietary Reduced Rats

This study attempted to prove our hypothesis that a short-term toxicity study, using a 4-day dosing regimen as an example, is suitable for evaluating myelotoxicity in rats. We compared the hematological, bone marrow cytological and histopathological results of 5-fluorouracil (5-FU) treated and pair-feeding groups after a 4-day administration period. Several experimental groups were defined for this 4-day study as well as for our previously reported 14-day study (Miyata et al., 2009); these included 5-FU treated groups receiving 12, 15 and 18 mg/kg/day (FU12, FU15 and FU18), pair-feeding groups (R12, R15 and R18 receiving the same amount of food as the FU12, FU15 and FU18 groups, respectively) and a nontreated control group. Although severe reductions in body weight gain and food consumption were reported in the 14-day study, only slight reductions were observed in the 4-day study. In the 4-day study, a decrease in blood reticulocytes and a decreasing trend of marrow erythroid cells were only observed in the FU18 group, and no effects were observed in the pair-feeding groups. The erythroblastic changes observed in this 4-day study were thought to reflect the direct influence of 5-FU administration. Since concerns regarding the influence of secondary changes related to undernutrition were minimized in the 4-day study, it was thought to clarify the direct influence of 5-FU administration on erythroblastic cells. Thus, a 4-day study protocol might be helpful for distinguishing secondary changes related to undernutrition.     

Evaluation of Low Level Laser Therapy on Primary Healing of Experimentally Induced Full Thickness Teat Wounds in Dairy Cattle

Objective —The purpose of this study was to evaluate the effect of low-level laser therapy (LLLT) on sutured wounds of the teat in dairy cattle.
Study Design —By using the Latin square design, the effect of LLLT was evaluated by radiography, measurement of microcirculation flow, histopathology, tensiometry, and hydroxyproline analysis.
Animals or Sample Population —Sixteen teats of four dairy cattle.
Methods —Full thickness wounds were made on the cranial surface of the teats. Teats were distributed into four groups; group A and B wounds were closed with a Gambee pattern, group C and D wounds were closed with three-layers of continuous suture pattern. Group B and D wounds were treated with 3.64 J/cm² of LLLT using a helium-neon system continuous wave (632.8 nm) output of 8.5 mW.
Results —The teat wall in non-LLLT groups was significantly thicker than in LLLT groups on day 7, 14 and 21. The mean blood flow differences between control and sutured sites in LLLT groups were significantly lower than those in non-LLLT groups. The morphology of the epidermis in LLLT groups more closely resembled the normal epidermis than that of non-LLLT groups. Collagen fibers in LLLT groups were denser, thicker, better arranged and more continuous with existing collagen fibers than those in non-LLLT groups. The mean tensile strength was significantly greater in LLLT groups than in non-LLLT groups.
Conclusion —The LLLT affects various aspects of the healing process, including minimizing inflammation, formation of edema, improvement of skin regeneration and enhancement of collagen synthesis.
Clinical Relevance —The LLLT could accelerate healing of sutured wounds of the teat in dairy cattle.     

Effect of monoenergetic neutron irradiation on the postnatal development of the cochlea in C3H/HeN mice

To investigate the toxic effect of neutrons at energies of approximately 1MeV on the ear, we exposed 7-day-old mice to 1.0 Gy of monoenergetic neutrons (1.026 MeV) or (137)Cs gamma rays, and assessed subsequent morphological changes in the inner ear by light and scanning electron microscopy. Monoenergetic neutrons, but not gamma rays, caused acute changes in the ear. The epithelium of the greater epithelial ridge in the organ of Corti had disappeared by 72 hr post-irradiation, as a result of epithelial apoptosis observed 6 hr post-irradiation. Radiation could induce apoptotic cell death of the epithelium of the greater epithelial ridge at 3 or 4 days of age. Protruding structures were detected on the surface of the hair cells by 72 hr post-irradiation. The neutron-irradiation also caused the apoptotic cell death of epithelial cells at the nasal conchae, and subsequent acute otitis media continued until 10 weeks of age.     

Incidence of Salmonella infection in healthy dogs in Gifu Prefecture,Japan

A total of 1,013 feces samples and 8 mesenteric lymphonodus samples obtained from apparently healthy dogs were examined for the incidence of salmonella infection. One strain of S. typhimurium (ST) was isolated from feces of one dog, and S. enteritidis (SE) was isolated from the mesenteric lymphonodus of one dog. Sera obtained from 330 apparently healthy dogs were examined for Salmonella antibodies using an ELISA with heated whole cells of SE and ST. Fifty-one of the 330 serum samples were considered to be positive for salmonella antibodies, including 12 which were SE-positive and 39 which were ST-positive. These results indicate that dogs cause possible environmental problems as Salmonella carriers.