An open cuvette for heating individual fruits on kiwifruit vines

Summary A set of cuvettes that heat individual fruits on a kiwifruit has been constructed. This apparatus will be used to determine how fruit characteristics are affected by temperature at various stages of fruit growth. The system consists of 25 cylindrical cuvettes each of which can be fitted around a single kiwifruit while it was still attached to a vine in the field. The cuvettes have no top or bottom, so air can move freely through them. Each cuvette is fitted with a 10 watt heating element that radiantly heats the fruit. A datalogger monitors cuvette temperatures and turns the heaters on and off via a multi channel controller. During a 5 d test period heated fruit were maintained at 4.5K ±0.1 (SD) above the temperature of ambient fruit. The cuvette system was tested on mature kiwifruit vines (Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson) for 48 d up to harvest. Heating increased the fresh weight and dry-matter content of fruit while delaying the rise in soluble solids concentration. The technique is useful for defining how fruit characteristics change with temperature. However, because only a small proportion of the fruit on a vine are heated, considerable caution is needed when interpreting results.

[1]  W. Snelgar,et al.  Relationship between canopy density and fruit quality of kiwifruit , 1998 .

[2]  J. E. Jackson,et al.  The causes of year-to-year variation in the average yield of Cox's Orange Pippin apple in England. , 1980 .

[3]  B. G. Coombe,et al.  Modelling grapevine phenology against weather: Considerations based on a large data set , 1993 .

[4]  I. Impens,et al.  Free Air Temperature Increase (FATI): a new tool to study global warming effects on plants in the field , 1996 .

[5]  A. Hall,et al.  Using early‐season measurements to estimate fruit volume at harvest in kiwifruit , 1996 .

[6]  T. Gillespie,et al.  A Small Infrared Thermometer for Measuring Leaf Temperature in Leaf Chambers , 1983 .

[7]  I. Warrington,et al.  THE EFFECT OF TEMPERATURE ON THE RATE OF KIWIFRUIT MATURATION USING CONTROLLED ENVIRONMENTS. , 1992 .

[8]  C. B. Tanner,et al.  Radiation Shields for Air Temperature Thermometers , 1965 .

[9]  J. P. Grime,et al.  A new technique for the experimental manipulation of temperature in plant communities , 1994 .

[10]  Errol W. Hewett,et al.  Maturation of kiwifruit grown at different temperatures in controlled environments , 1996 .

[11]  E. F. Walton,et al.  Changes in abscisic acid concentration, surface conductance, and water content of developing kiwifruit , 1995 .

[12]  W. Snelgar,et al.  Effect of increased preharvest temperature on fruit quality of kiwifruit (Actinidia deliciosa) , 1989 .

[13]  W. Snelgar,et al.  Predicting harvest date for kiwifruit: Variation of soluble solids concentration with mean temperature , 1993 .

[14]  A note on recognizing autocorrelation and using autoregression , 1999 .

[15]  J. C. Ferguson,et al.  A chamber-free method of heating and cooling grape clusters in the vineyard. , 2000 .

[16]  T. Sinclair,et al.  Solar heating of grape berries and other spherical fruits , 1976 .