摘要:

Vine growth, pruning requirements, yield, and postharvest storage of kiwifruit (Actinidia deliciosa)grown on five different vine support structures were compared over 5 years from grafting. Support structures were winged T‐bars and pergolas (standard structures), Lincoln T‐bars, divided T‐bars, and A‐frames. Cumulative length of fruiting canes in the 3 years to full canopy closure was greatest for Lincoln T‐bars, A‐frames, and pergolas, and least for winged and divided T‐bars. The proportion of budbreak was higher on pergolas than on the three T‐bar systems and was least on A‐frames. Floral budbreak and flowers per floral shoot were also lower on A‐frames than on the other systems. Cumulative yields of export fruit were highest for pergolas and winged T‐bars, and lowest for A‐frames. Differences in postharvest storage were detected between fruit from different structures, but these differences were not consistent among years. The time required to prune each vine was least for pergolas and winged T‐bars. Vines on A‐frame structures took substantially more time to prune than vines on pergola structures.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513785

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The mating type of strains ofBotrytis cinerea(teleomorphBotryotinia fuckeliana) from a diverse range of hosts and locations throughout New Zealand was determined by crossing with tester strains of known mating type. Most isolates were hetero‐thallic, 24 carrying theMAT 1–1allele and 17 theMAT1–2allele, but 9 were homothallic. The mating type alleles were widely distributed with respect to host, district, and fungicide resistance genes. Fungicide resistance phenotypes segregated as distinct characters consistent with the presence of the previously recognised genesMbcl,conferring resistance to benzimidazole fungicides, andDafI,conferring resistance to dicarboximide fungicides. A new allele is recognised,DafIUR,encoding ultra‐low level dicarboximide resistance not associated with abnormal osmotic sensitivity. Pairing of single ascospore strains on malt extract agar amended with 0.68M NaCl demonstrated a mycelial incompatibility system in this fungus.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513786

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Six sap‐transmitted viruses were identified during a study of 434 flowering cherries in the North Island of New Zealand. These includedPrunusnecrotic ringspot ilarvirus (PNRSV), apple mosaic ilarvirus (ApMV), flowering cherry virus B (FCVB), strawberry latent ringspot virus (SLRV), prune dwarf ilarvirus (PDV), and flowering cherry virus I (FCVI). Of these, ApMV, FCVB, SLRV, and FCVI were new records for this host. FCVB and FCVI appear to be newly described viruses with characteristics of members of the bromovirus and ilarvirus groups respectively. The most common virus was PNRSV (30.6%); the other viruses ranged in incidence from 10.2% (FCVB) to 0.5% (PDV). A further 43 virus isolates were categorised into nine classes based on symptoms inChenopodium quinoaand cucumber, and were not further characterised in this study. Repeated sampling of 30 flowering cherry trees during late winter and early spring showed that the enzyme‐linked immunosorbent assay (ELISA) was more sensitive for detecting PNRSV infection of flowering cherries than sap transmission, but that neither method was absolutely reliable.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513787

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The increase in soluble solids concentration (SSC) of kiwifruit (Actinidia deliciosacv. Hay ward) maturing on the vine was monitored in 35 orchards in eight regions of New Zealand during 1981 and in 37 orchards during 1982. During these 2 years the date of commercial maturity (SSC of 6.2%) ranged from 16 April at Nelson to 25 May at Kerikeri, a spread of 39 days. It tended to be earliest at the southern‐most and hence coolest sites. A simple model that has been used by others to predict the date of commercial maturity was tested. This model relates the time taken for fruit to increase in SSC from 5.0 to 6.5% to the mean air temperature during that period. Our data confirmed that the rate of increase in SSC increased as the mean temperature decreased from 15 to 11°C. However, the predictive model was not consistent between or within seasons. There is some evidence that this lack of consistency is caused, at least in part, by factors other than temperature influencing the rate of SSC increase. The rate of increase in SSC was inversely correlated with the date that fruit in the orchard reached a SSC of 5.0%. This suggests that the state of vine development influences the rate of maturation. It is also possible that the description of temperature was inappropriate, either in the use of mean temperatures, or because air temperatures recorded at standard meteorological sites did not adequately represent the temperature of the fruit.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513788

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The effect of (2‐chloroethyl)phosphoric acid (ethephon) on the abscission of mature ‘Beaumont’ macadamia nuts (Macadamia integri‐folia × M. tetraphylla) was investigated in two experiments. In 1988, 6‐year‐old trees were treated with 200 or 400 mg/litre of ethephon, with and without pH neutralisation or a surfactant, 2 weeks after nut maturity. Nut abscission increased from 6% on untreated trees to a maximum of 87% on trees treated with a 400 mg/litre neutralised solution of ethephon which included a surfactant. Trees treated with 400 mg/litre ethephon sprays showed a large but nonsignificant reduction in yield in the following season. A second experiment in 1990 determined the effects of three ethephon rates (400, 500, and 600 mg/litre) applied on three separate dates (nut maturity, nut maturity +2 weeks, and nut maturity +4 weeks). In this study 70% of nuts abscissed after the final application compared to only 7% on untreated trees. However ethephon applied 2 or 4 weeks after the nuts matured caused significant flower damage and crop loss in the following season. Despite the enhancement of abscission rates, ethephon cannot be recommended for application to ‘Beaumont’ macadamia trees in New Zealand because of the loss of subsequent yields.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513789

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Asparagus (Asparagus officinalisL.) spear tips lose sucrose rapidly after harvest and this probably contributes to spears’ short postharvest life. As the first step towards controlling this loss of sucrose and possibly improving postharvest life, the activities of sucrose‐cleaving enzymes, and levels of sugars were measured in tips and 3 cm sections of spears from tip to butt. Sucrose was the major sugar in tips but not in the rest of the spear. Glucose and fructose were almost equimolar throughout the spear and increased fivefold from tip to butt. Fructose was always slightly more abundant than glucose. Sucrose synthase, bound acid invertase, and neutral invertase activities were similar in both tips and spear sections. Soluble acid invertase activity in the middle section of the spear was 4—5 times that of tips and butts. Sugar composition and enzyme activities in spear sections and tips were not closely correlated.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513790

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Embryo, ovule, and ovary development were studied inLimonium perigrinum(Bergius) following self‐ and cross‐pollinations. Four types of ovule were identified on the basis of their growth patterns and distinct morphological features. Fifty‐six percent of the cross‐pollinated florets but only 18% of the self‐pollinated florets produced embryos that developed normally. Forty‐four percent of the self‐pollinated florets produced embryos that ceased development at the globular to heart stage of development (within 18 days of pollination), whereas only 6% of the cross‐pollinated embryos ceased development at a similar stage. A similar proportion of self‐ and cross‐pollinated florets (36%) failed to develop embryos.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513791

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The viability of kangaroo paw pollen (Anigozanthos manglesii) was estimated by germination in vitro and by fluorescence and the more reliable method was then used to assess the effect of storage conditions on pollen longevity. Pollen germination was more accurate than staining for pollen of low and intermediate viability levels. Effective storage could be achieved in a number of ways depending on the duration required. Dehydrated pollen retained viability longer in storage than did hydrated pollen. Pollen from intact anthers could be stored for up to 5 weeks at room temperature with 50% or better germination provided it was stored on silica gel. Pollen isolated from anthers and stored at 2°C had reduced viability in comparison with that stored at room temperature or at ‐80°C. Pollen stored at ‐196°C lost only 5% viability after 20 weeks and presumably this would be the most suitable method for long term storage for breeding or conservation purposes.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513792

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Asparagus spears (Asparagus officinalisL. cv. Limbras 10) were stored for 3–5 days in atmospheres containing between 40 and 90% carbon dioxide (CO2) to evaluate the effect of insecticidal CO2atmospheres on sensory quality based on sensory panel ratings of characteristic asparagus flavour, off‐flavours, flavour acceptability, andoverall acceptability. Sensory quality of spears after 4 days storage in 60% CO2was similar to air‐stored spears but 5 days storage caused deterioration in the CO2‐stored spears relative to the air‐stored spears. Using higher CO2levels than this for shorter storage times resulted in spears with CO2injury and poor sensory quality. Spear quality deteriorated with shelf period but previous CO2treatment did not affect the rate of deterioration. Storing spears at 5°C in 60% CO2or 0°C in air gave consistently higher (lower for off‐flavours) sensory quality ratings for all characteristics assessed than vice versa. Thick spears had more flavour and were more acceptable than thin spears. Thick spears had more flavour than thin spears when stored in CO2, but thin spears had more flavour when stored in air than in CO2. In 60% CO2, spears stored dry had a more acceptable flavour and were more acceptable overall (where panellists considered aspects such as flavour, texture, and off‐flavours in the overall rating) than those stored with their butts in water. Spears stored in air with their butts in water had a more acceptable flavour and were more acceptable overall, spears stored with their butts in water had less characteristic asparagus flavour than those stored dry. High levels of CO2could be used as a disinfestation treatment of fresh asparagus spears without significant effect on spear quality (compared to spears stored in air under similar conditions) providing levels >60% CO2are not used, and storage time in the atmosphere is kept to 4 days or less.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513793

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The postharvest response ofLimonium perigrinuminflorescences to cool storage and preservative solutions was examined as part of the development of a new cut flower crop. The inflorescence is comprised of many individual flowers, whose sepals remain open and have decorative value long after the petals have deteriorated. This results in a long natural display life of 30–40 days immediately after the inflorescence has been harvested. Sugar or chrysal preservative solutions increased the number of flower buds that opened and the length of time that flowers with open petals were present on an inflorescence after harvest. Display life, however, was decreased to between 10 and 20 days. If inflorescences were stored for 72 h after harvest, display life was reduced to 20–25 days. Cool storage (5°C) and rehydration of inflorescences after storage in a sugar solution, increased the time that flowers with open petals were present but did not increase overall display life. The use of preservative solutions may not be appropriate given the length of the normal display life.

ISSN:0114-0671    

DOI:10.1080/01140671.1993.9513794

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor