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Juiciness and freshness play a critical role in consumers’ choice of apples, and objective measurements of the traits are essential for adding a premium to fruits with high consumer demand. Juiciness and freshness were sensory evaluated by four apple-breeding experts. The score of sensory juiciness decreased with decreased instrumental measurements of water content (WC), firmness, and apoplastic solution (AS). The influence of firmness on sensory juiciness was not linear, and perception of juiciness rapidly decreased when firmness decreased below 60 N. The sensory freshness score was related to titratable acidity (TA), firmness, and the AS. A nonlinear regression model for freshness indicated that freshness was less likely to be perceived as the AS in flesh tissue decreased, and the perception of freshness rapidly decreased when firmness decreased below 60 N or TA decreased below 0.25 g 100 ml−1. The firmness of fruit treated with 1-MCP hardly decreased during storage. The titratable acidity of fruit treated with 1-MCP decreased; however, the degree of the decrease was significantly lower than that of non-treated fruit. The AS immediately decreased just after harvest and was not significantly different in most cases between 1-MCP-treated and non-treated fruit during storage. Therefore, measurements of firmness and TA were useful for distinguishing 1-MCP-treated fruit from non-treated fruit and the AS is necessary to distinguish between stored fruit and that just after harvest. The performance of calibration models developed by NIR spectroscopy for TA, firmness, and AS was lower than that for soluble solids content (SSC), which is used to grade apples by NIR spectroscopy in Japanese packing houses. Therefore, it is impractical to grade fruit by freshness using calibration models. However, high correlation coefficients were obtained in the calibration model for WC. The correlation coefficient of WC was about as high as that of SSC. Therefore, apples could be graded by juiciness using the calibration model for WC with the auxiliary use of calibration models for firmness and AS.

Fruit thinning is an essential part of the commercial production of quality apples. A portion of the excessive fruitlets is abscised, or shed, physiologically as a self-regulatory mechanism; however, the degree of abscission varies depending on the environmental conditions and cultivars. The number of abscised fruitlets within a cluster is influenced by the number of leaves in the cluster. In some cultivars, the fewer leaves there are in a cluster, the larger the number of fruitlets undergo abscission is. Conversely, the growth rate of a fruit cluster is marginally influenced by the number of leaves in the cluster and appears constant for each cultivar. The constant growth rates of fruit clusters indicate the source strength, which supports the growth of individual fruitlets (sink organ) on the tree. The cultivar differences in the percentage of fruitlet abscission were highly correlated with the source strength of the cultivars, indicating that the rate of abscised fruitlets was determined by the source strength of the cultivars. The number of days between full bloom and diminishing growth of abscising fruitlets was also correlated with the source strength. Therefore, a cultivar with low source strength is prone to abscising many fruitlets at an early date compared with one with high source strength. The source strength of a cultivar, therefore, can be a useful index for selecting cultivars characterized by easy and early abscission.

Lyssaviruses, including rabies virus (RABV) and Australian bat lyssavirus (ABL) are a globally distributed genus of zoonotic pathogens that cause rabies disease with a case-fatality rate in humans of 100%, resulting in over 61,000 deaths/year. To understand the mechanisms underlying lyssavirus evasion of interferon (IFN)-mediated antiviral immune responses, we have used a multidisciplinary approach combining techniques including viral reverse genetics and in vivo infection, next-generation sequencing/bioinformatics, single live-cell imaging (including novel live-cell microtubule-association assays), super-resolution dSTORM microscopy, immune signalling assays, and protein–protein interaction analysis. This work has determined that the lyssavirus IFN-antagonist P-protein forms a complex array of molecular interactions in host cells, including with STATs 1 and 2, microtubules, nuclear import and export receptors, and intranuclear structures [1] , [2] , [3] , [4] . Recently, we have identified novel interactions with STAT3, which enable inhibition of signalling by several cytokines [3] , and with nucleoli, and have found that P-protein specifically alters microtubule structure and dynamics. Using mutagenesis to modify specific association sequences in P-protein, we have determined that many of these interactions are critical to infection in vivo [1] , [4] . In particular, we found that interactions of lyssavirus P-proteins with STATs are conserved across the lyssavirus genus [2] , and that mutagenic inhibition of these interactions results in strongly reduced growth of virus in the CNS of infected mice to attenuate pathogenicity, such that the mutated virus causes no neurological symptoms or death compared with the invariably lethal wild-type strain [1] . Similarly, our recent studies using mutation of virus to prevent P-protein subcellular trafficking and modulation of microtubule structure indicate that this strongly impairs IFN-antagonist function, resulting in attenuation in vivo. Together, these studies demonstrate critical roles in disease of diverse interactions that underlie viral antagonism of cytokine signalling; this identifies novel targets for the generation of attenuated vaccines and antiviral drugs. Our current studies, which include structural analysis using NMR and crystallography, seek to exploit this knowledge to generate new approaches to combat rabies disease.