Taylor & Francis
New Zealand Journal of Experimental Agriculture
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25
Preliminary investigation of a small fruit problem in kiwifruit,Actinidia deliciosa
Haslam S.K., Hanson J.S., Hanson A.J.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 0, doi.org, Abstract
It was suspected that disease caused the developmentof small fruitin kiwifruit. Accordingly, the development of the fruit from female flowers infected with blossom rot was followed. A large number of these infected flowers did not develop into fruit and the remainder developed into ‘dropped shoulder’ or small deformed fruit with some seedless carpels. Removal of some stigmas and styles from healthy flowers also produced ‘dropped shoulder’ fruit. Removal of part of each stigma from healthy flowers did not, however, affect the shape and size of the resultant fruit. The mechanism of the development of the deformed fruit is discussed.
Temperature studies on kiwifruit vines using relocatable greenhouses
Snelgar W.P., Bayley G.S., Manson P.J.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 9, doi.org, Abstract
A set of eight relocatable greenhouses has been built for studies of temperature effects on mature kiwifruit vines (Actirddia deliciosa (A. Chev.) C. F. Liang et A. R. Ferguson) growing in a typical orchard. Each greenhouse covers one half of a vine planted at 6 m within-row spacing on a T-bar trellis. Temperatures within the greenhouses are maintained at a constant differential above ambient air temperature. Details of the construction, operation, and performance of the greenhouses are provided. In an initial experiment carried out in spring 1985, the mean air temperature was increased by 0.7° C or 4.9° C for 41 days. At the higher temperature, bud burst was advanced by 7 days and full bloom by 14 days. In the wanner greenhouses, growth of the apical shoot was increased and the percentage of shoots which produced flowers was reduced. An interaction between the warmed and untreated halves of the vines was observed.
A review of kiwifruit pollination: Where to next?
Craig J.L., Stewart A.M., Pomeroy N., Heath A.C., Goodwin R.M.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 21, Обзор, doi.org, Abstract
The likely role of various pollination vectors is considered in the context of flower anatomy and the published results of past experiments. A number of insects visit flowers of both female and male vines but there is as much evidence implicating wind as there is for an insect vector. Most experiments that investigated a likely role of wind alter wind flows and are confounded by the presence of honey bees. Similarly, evidence taken as support for the role of honey bees is confounded by the action of wind. Recent studies suggest that individual bees tend to work the flowers of one sex of vine or the other. Existing methods of measuring pollination effectiveness in kiwifruit are also questioned as is our understanding of incompatibility responses. An experiment that can help resolve these problems is outlined briefly.
Effect of irrigation on yield, berry weight, and sugar content of blackcurrants
McCarthy T.P., Stoker R.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 2, doi.org, Abstract
Blackcurrant bushes (cv. Magnus) planted on a free-draining Lismore stony silt loam were used to study the yield responses to four irrigation regimes, using one unirrigated and three irrigated treatments. Irrigation treatments were applied each time gravimetric soil samples (0–150 mm deep) taken 300mm from the hedgerow fell to 10,15,or20%soil moisture (s.m.) content. In the first two years, the 15 and 20% s.m. treatments produced yields 150-220% higher than both the unirrigated and infrequently irrigated 10% s.m. treatments. As the unirrigated and 10% s.m. treatment bushes developed with time, the annual yield differences decreased to a level where, by the fifth harvest, the 15 and 20% s.m. treatment yields respectively were only 15% and 37% higher than the unirrigated treatment yield. Average berry weight increased with irrigation frequency during the first three seasons. However, differences in berry weight decreased gradually with timeandby the 1986/87 season showed no significant differences ...
Book review
Genet R.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 0, Обзор, doi.org
Factors influencing the aroma volatiles, sugars, and acids of boysenberry fruit
Porter N.G.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 1, doi.org, Abstract
The effects of genotype and handling practices on flavour components of boysenberries were determined. Headspace analysis, vacuum distillation, and gas chromatography-mass spectroscopy (GC-MS) were used to identify and measure aroma volatiles of which linalool was the predominant compound. Sugars and acids were analysed by gas chromatography (GQ) and high pressure liquid chromatography (HPLC). Fructose and glucose were the major sugars and were present in similar amounts. The major acids were citric acid and malic acid. Sucrose and succinic acid were present at very low levels. Differences in individual and total sugars, the sugar:acid ratio, and the levels and composition of the aroma volatiles were found between genotypes, harvest times, and freezing treatments. Sugar levels were more affected by experimental treatments than acid levels. ‘Boysenberry’ had higher sugar levels and a sweeter suganacid ratio than ‘Youngberry’. Sugar levels and suganacid ratio in ‘Boysenberry’ were highest at night....
Red tamarillos (Cyphomandra betacea): Comparison of two postharvest dipping strategies for the control of fungal storage disorders
Yearsley C.W., Huang B.Y., McGrath H.J., Fry J., Stec M.G., Dale J.R.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 2, doi.org, Abstract
The fungicides imazalil and prochloraz suppressed the in vitro growth of four fungal storage pathogens of tamarillos (Colletotrichum gloeosporioides (Penz.) Arx, C. acutatum Simmonds, Phomopsis sp., and Phoma exigua Desm.). Imazalil was as effective as prochloraz against P. exigua but prochloraz was more effective against C. gloeosporioides, C. acutatum, and Phomopsis sp. The proportion of fruit affected by four storage disorders (body lesions, stem-end lesions, calyx mycelium, and calyx necrosis) was reduced after dipping with prochloraz (250–1000 mg/litre) compared with fruit dipped in cold water (CW). A combined imazalil and prochloraz dip (CF) resulted in the greatest reduction in these disorders. Fruit from one orchard were dipped and stored for4,6,and8 weeks at3.5± l° Cfollowedby 1 week at 20 ± 2° C. The number of sound fruit after storage was increased by 36% and 35% respectively for the CF strategy and the hot water dip (HW) when compared with the cold water dip (CW). In fruit that were c...
Sally Diane Newton M.Ag. Sci (Hons), Ph.D (Cant) 1952–1988
Robertson A.G.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 0, doi.org
The effects of grazing on components of grain yield in winter barley
Scott W.R., Hines S.E., Love B.G.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 4, doi.org, Abstract
A paddock-scale experiment was conducted over two seasons to determine whether winter barley will fit adequately into a fanning system that requires both feed and grain, and to investigate how grazing affects the grain yield components. The 6-row ‘Illia’ and 2-row ‘Priver’ cultivars produced 1.3–2 t/ha of DM by mid August when sown in April. Grazing to ground level in August reduced grain yields by about 10%, by reducing the ear population, despite the fact that mainstem apices were below soil level at thetime of grazing. Combine harvested grain yields ranged from 2.3 to 3.6 t/ha in seasons with below average rainfall.
Changes in quality of ‘Red Delicious’ and ‘Golden Delicious’ apples following delayed cooling versus delayed establishment of controlled atmosphere storage
King G.A., Henderson K.G.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 2, doi.org, Abstract
‘Golden Delicious’ and ‘Red Delicious’ apples (Malus domestica Borkh.) were cooled (0.5° C) or placed in controlled atmosphere (CA; 2% O2,2% CO2 at 0.5 or 25° C) 3, 8, or 14 days after harvest. Weight loss, background colour, acidity, and eating acceptability were assessed after 16 and 24 weeks for ‘Golden Delicious’ and ‘Red Delicious’ respectively. Fruit that had been cooled or placed in CA 3 days after harvest, had lower weight loss, less yellow background colour development, lower acid loss, and better eating acceptability than fruit that was cooled or placed in CA 8 or 14 days after harvest. Firmness of ‘Red Delicious’ apples was better retained by early cooling than by early CA establishment ‘Red Delicious’ apples should be cooled within 3 days and the CA established within 14 days of harvest to maintain quality during long term storage. Firmness of ‘Golden Delicious’ apples was better retained by the combined effect of cooling and placing apples in CA 3 days after harvest.
Hydraulic properties and ‘field capacity’ of Himatangi sand
Swain D.J., Scotter D.R.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 6, doi.org, Abstract
Bulk density, particle size, soil water retentivity, and saturated and unsaturated hydraulic conductivity data from Himatangi sand are reported. The soil under a 4 m2 area was wet by ponding and the subsequent decline in soil water contentmonitored using a neutron probe. The drainage rate from the top 550 mm of the soil profile was greater than 1 mm/day for 6 daysafter ponding ceased, indicating that the commonly accepted concept of field capacity is inappropriate for this soil. Simple theory is developed which allows prediction of drainage losses under different soil water and evapotranspiration conditions. If the upper limit of readily available water is taken as the storage when the drainage rate from a 550 mm deep root zone is 1 mm/day, and the lower limit is taken as the storage at a matric potential of-50 kPa, then the readily available water holding capacity is only 8 mm. This suggests that carefully controlled high frequency irrigation is necessary if both drainage losses and plant water ...
Factors limiting postharvest display life ofLeucospermumcv. Firefly
Downs C.G., Reihana M.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 0, doi.org, Abstract
Display life of Leucospermum cv. Firefly is restricted by foliage damage. Treatment with sucrose solutions, either continuously during display (1% sucrose) or for a 24 h pulse treatment at 20° C (5% sucrose), failed to reduce leaf desiccation. Continuous 5% sucrose treatment induced more severe leaf damage and reduced leaf display life further, whereas flower head display was increased greatly with continuous sucrose treatments. Preservatives improved the water balance (expressed as nett water loss) of inflorescences during display life, but failed to reduce the rapid decline in water uptake that occurred during the first days of display. During continuous treatment, transpiration was reduced, possibly as a result of greater leaf damage in treated inflorescences.
Some factors predisposing grape berries to infection byBotrytis cinerea
Nair N.G., Emmett R.W., Parker F.E.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 17, doi.org, Abstract
Botrytis cinerea was frequently isolated from rapidly senescing or moribund tissues (stamens, calyptrae, immature berries and flowers or partly developed berries, miscellaneous leaf, stem and tendril pieces) of grapevine; the calyptrae being more heavily contaminated than the stamens in the flower bunches. There was a significant difference in the extent to which intact and injured berries were infected by the pathogen 3 weeks before harvest. Bunches infested with light-brown apple moth (Epiphas postvittana (Walker)) were more rapidly infected by B. cinerea. Of thecultivars tested, ‘Mataro’ was the least susceptible to predisposition wounding because the berries had a high critical turgor; however, once the berries were split, they appeared to be as susceptible to infection as the other cultivars tested. The longer the berries were exposed to surface wetness, the higher the degree of infection. A minimum temperature difference of 9°C caused a significant difference of 6-12 h in the length of the ...
Selection of fungal antagonists for biological control of onion white rot in New Zealand
Harrison Y.A., Stewart A.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 19, doi.org, Abstract
Six fungal species were selected from a total of 76 on the basis of their antagonism to the onion white rot pathogen, Sclerotiurn cepivorwn, in dual culture. Gliocladium roseunt, G. virens, Trichoderma viride and Coniothyrium minitans exhibited their antagonism by competing successfully with the pathogen for space and nutrients whilst Chaetomium globosum and Penicillium expansion released antibiotic substances into the agar medium which inhibited the growth of S. cepivorwn at a distance. Four of the six test fungi were also able to colonise and degrade sclerotia of the pathogen. Gliocladium roseum was tolerant of the dicarboximide fungicides, iprodione, vinclozolin and procymidone. None of the antagonists were pathogenic on onion seedlings in vitro and they therefore show promise for use as biocontrol agents against onion white rot.
Effect of shelter, irrigation, and plant population on yield and yield components of navy beans (Phaseolus vulgarisL.)
Love B.G., Askin D.C., McKenzie B.A.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 3, doi.org, Abstract
In two growing seasons, navy beans cv. Sanilac were sown at populations ranging from 44 to 120 plants/m2 with or without irrigation and shelter in Canterbury. In the two seasons, rainfall was 156% and 66% of the long term mean. Irrigation had the largest effect on seed yield. In 1983/84 irrigated plants yielded 319 g/m2 and unirrigated plants only 278 g/m2. In the drier season, irrigated plants yielded 309 g/m2 while the dryland crop yielded only 131 g/m2. Shelter had only a small effect on seed yield, in only one season, despite reducing wind run by about 40%. Generally, higher plant populations resulted in higher seed yields particularly with irrigation. However in 1984/85, unirrigated crop yield with 30 plants/m2 was 135g/m2andat 120plants/m2 only 125 g/m2. The results indicated that navy beans should be grown with irrigation in Canterbury to be a viable farm option. High plant populations may produce higher yields and ease harvesting problems.
Quality in New Zealand-grown onion bulbs—a survey of chemical and physical characteristics
Lancaster J.E., Reay P.F., Mann J.D., Bennett W.D., Sedcole J.R.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 4, doi.org, Abstract
A survey of ripened onion (Allium cepa L.) bulbs, collated from field-grown crops in the commercial areas of New Zealand, was undertaken to investigate how the characteristics of flavour precursors, phenolics, sugars, dry matter, and hardness varied. The majority of samples were of ‘Pukekohe Long Keeper’ (PLK) and the early selection of this cultivar, ‘Early Long Keeper’ (ELK). A sample of the white onion ‘Dehyso’ and three Japanese onion cultivars was obtained for comparison. Percentage dry matter (DM %) for PLK and ELK for the 1983 harvest was similar for all sites and averaged 13.4%; total sugars averaged 0.45 mmole/g fresh weight. The white ‘Dehyso’ onions had a higher dry matter percentage (DM%) (15.9%) and a greater proportion of fructose compared with glucose than PLK or ELK onions. PLK and ELK samples collected from one site in 1984 had significantly different DM% and total sugars compared to other sites. There was a significant difference in average fresh weight for bulbs between sites. ...
An evaluation of the physical properties of some Gisborne Plains soils for irrigation purposes
Gradwell M.W., Rijkse W.C.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 9, doi.org, Abstract
Undisturbed samples were taken, at depths from 7 to 80 cm from six soils representative of major series on the alluvium of the Gisborne Plains. Determinations were made of hydraulic conductivity at the water contents prevailing soon after drainage, of the tension/water content relationship, and of air content at a tension of 50 cm of water (‘large pores’). Hydraulic conductivities were high to medium for soils classed as recent, and low for the gleyed recent and older gley soils; large pore contents were reasonably high for all soils, and capacities for storing plant-available water were average for five of the soils but above average for the soil on the most recent flood deposits. Replicated samples were taken at certain depths. Statistical analysis on the test results from these showed that the standard errors of the properties measured were rather low and that hydraulic conductivity was isotropic. Soil horizons containing Taupo Pumice had anomalous properties, including low density, high hydra...
Flight activity and weed hosts of Macrosiphini (Homoptera: Aphididae) in Canterbury
Farrell J.A., Stufkens M.W.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 4, doi.org, Abstract
The flight activity of 29 species of Macrosiphini, recorded over 6 years in a suction trap at Lincoln, is reported. Flight phenology and weed hosts of 20 species are described. The host plant relations of Myzuspersicae (Sulzer) were examined. Mallow (Malva neglecta Wallred) and black nightshade (Solarium nigrum L.) were favourable hosts, while few M. persicae were found on white clover (Trifolium repens L.) or yarrow (Achillea millefoliun L.). Aulacorthum solani Kaltenbach was the predominant aphid species on white clover and yarrow in the field, together with Myzus ascalonicus Doncaster on yarrow. These three aphid species were vectors of beet western yellows virus (BWYV), while hosts of BWYV include the weed species named. It is suggested that BWYV has a broad ecological base of hosts and vectors in Canterbury.
Sero-groups ofErwinia carotovoraassociated with water, soil, tuber, and stems of potato plants in Western Australia
Peltzer S., Sivasithamparam K.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 6, doi.org, Abstract
Soft-rot erwinias were isolated from irrigation water, soil, tubers, and stems from spring (1986) and summer (1987) crops of potato at a field in Manjimup, Western Australia. Most of the isolates from all environments in both seasons belonged to Erwinia carotovora pv. carotovora (Ecc), with the exception of those from stems of the summer crop which were predominantly (68%) Erwinia carotovora pv. atroseptica (Eca) and belonged to sero-group SGI. In spring, SGIII was recorded from all environments tested, while SGI was found only in stems and tubers. SGVI was recorded from stems (8%) and soil (15%) only in summer and in water (6.4%) only in spring. In spring, SGV, which was the predominant (28.2%) sero-group isolated from stems, was also found in water, soil, and tubers. In summer, of the SGs isolated from stems, SGIII occurred in soil and tubers and SGVI in soil. Although SGXXIX was the most common in water in both seasons, it was isolated from stems only in summer. In a pathogenicity test, repres...
Population density of the rose-grain aphid,Metopolophium dirhodum, on four cereal species in Canterbury
Farrell J.A., Stufkens M.W.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 0, doi.org, Abstract
Similar numbers of adult winged rosegrain aphid (RGA), Metopolophium dirhodum (Walk.), per unit area were recorded as immigrants on autumn-sown wheat, oats, barley, and rye in May-June 1987 at Lincoln.RGA population growth occurred at a similar rate up to the three-node stage of plant growth on these four cereals, and on wheat and barley blocks monitored in 1985. Subsequently, RGA numbers declined on wheat in 1985, and on wheat and rye in 1987, but population growth continued to a peak at heading or booting stages on barley and oats. Similarly, in a 1984 cultivar trial, scores for RGA infestation were consistently greater on barley and oat cultivars, than on wheat, triticale and rye, during the booting to flowering period of plant growth. The expression of resistance to RGA in older wheat and rye was thought to be partly associated with the rate of leaf senescence which reduced the area of feeding sites on sheltered lower leaves.
Evaluation ofAsparagus officinalisL. germplasm for resistance toStemphyliumleaf spot
Bansal R.K., Menzies S.A., Broadhurst P.G.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 3, doi.org, Abstract
Asparagus officinalis L. accessions were screened for resistance to Stemphylium leaf spot under controlled environmental conditions. The plants were inoculated with a conidial suspension of two isolates of Stemphylium sp. from asparagus. Disease severity assessments, based on percentage stem area necrosis (% SAN), were made 13—17 days after inoculation. Estimates of mean % SAN ranged from 31 to 74%. None of the accessions showed outstanding levels of resistance, but significant differences were observed in disease susceptibility between accessions. The accessions also differed for within-accession variability. Selection for increased levels of resistance is likely to be most effective in accessions with high within-accession variance values.
Seasonal frost tolerance of some ornamental evergreen broad-leaved and coniferous tree and shrub species
Stanley C.J., Warrington I.J.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 8, doi.org, Abstract
The seasonal frost hardiness of several ornamental species was evaluated by exposing intact plants to controlled advective frost conditions in spring, midsummer, autumn, and midwinter. Cultivars of the evergreen broad-leaved species Camellia japonica, Daphne odora, Desfontainea spinosa, Grevillea × gaudi-chaudi, Hardenbergia violacea, Hypericum × moserianum, Nandina domestica, and Photinia serrulata × glabra ‘Rubens’ all developed limited winter frost hardiness with the most hardy (Camellia and Photinia) being killed at temperatures below-17°C. Generally, evergreen broad-leaved species from northern zones were more tolerant than Australasian species. Of the ornamental conifers examined, Cupressus macrocarpa was only moderately hardy in winter, being injured by temperatures lower than-8°C and killed below-14°C, whereas Juniperus chinensis tolerated temperatures down to-19°C without injury. The summer frost tolerance of all of these species was similar and all were injured or killed by temperatures...
Resistance to the rose-grain aphid (Metopolophium dirhodum(Walk.)) in non-glaucous spring barley
Farrell J.A., Stufkens M.W.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 2, doi.org, Abstract
A non-glaucous leaf variant of a spring barley (Hordeum vulgare L.) breeding line was shown to support significantly fewer rose-grain aphids (Metopolophium dirhodum (Walk.)) than did cv. Triumph or glaucous-leaf variants of the same line. Aphid resistance in the non-glaucous line was associated with reduced immigration by winged rose-grain aphids.
The economics of herbicide use in cereal crops in New Zealand
Bourdôt G.W., Saville D.J.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 2, doi.org, Abstract
A simple model of net return for herbicide usage in cereals, based on yield losses caused by weeds, was used to derive breakeven losses for herbicides used in New Zealand. For wheat crops with average yields (4.5 t/ha) at 1987 prices, breakeven losses varied from 2.1% to 9.2% for weeds other than wild oats (Avena fatua), and from 6.4% to 14.1 % for wild oats. For barley crops with average yields (4.5 t/ha), breakeven losses varied from 3.0% to 13.1% for weeds other than wild oats, and from 9.1% to 20.2% for wild oats. A comprehensive survey of yield losses attributable to weeds in cereal crops has not been undertaken in New Zealand. However, using data available from Canada, breakeven yield losses would usually be exceeded for most of the 28 herbicides used in New Zealand cereal crops. On this basis there is no economic justification for the current trend toward reduced herbicide use in cereals.
Book reviews
Rae A.N., Hartill W.F., Wearing C.H.
Taylor & Francis
New Zealand Journal of Experimental Agriculture, 1988, цитирований: 0, Обзор, doi.org
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