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    Comparative benefits of orange heirloom tomatoes over red tomatoes for bone health : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science at Massey University, Manawatū, New Zealand
    (Massey University, 2022) Walallawita Kankanamge, Umani Shanika Walallawita
    Bone loss, common in women after menopause, is characterized by reduced bone mineral density with disruption of bone microarchitecture, leading to higher fracture risk and osteoporosis. There are few treatments, and most have adverse side effects. Intervention studies have shown protective effects of lycopene against bone loss in animal models. Lycopene is a lipid-soluble carotenoid found mainly in tomatoes. The molecule exists in all-trans- and a variety of cis- configurations; and cis- lycopene isomers have been reported to be more bioavailable than all-trans-. ‘Moonglow’, an orange heirloom tomato, contains >90% of its lycopene in cis- isomeric form and thus may be a better source of naturally bioavailable lycopene than red tomato, which contains all-trans- lycopene. We hypothesised that consumption of moderate daily doses of whole ‘Moonglow’ tomato would reduce bone loss more effectively than red tomato in rat and cell models of osteoporosis. In vivo, ‘Moonglow’ tomato supplementation delivered physiologically relevant plasma lycopene concentrations within four days of feeding. The post-ovariectomy rat model was successful in accelerating bone loss. ‘Moonglow’ tomatoes delivered a higher plasma lycopene concentration than red tomatoes and were beneficial in reducing a bone turnover marker compared to red tomatoes, even when fed after initiation of bone loss, but did not improve bone mineral density. Ovariectomy reduced gut bacteria abundance; compared to red, ‘Moonglow’ tomato feeding restored the numbers of Lactobacillus, Enterococcus, Bacteroides and E. coli. In vitro cell culture studies showed that both red and ‘Moonglow’ tomato hexane extracts induced a significant decrease in the number of bone-resorbing TRAP-positive osteoclasts at 10 µmol/L lycopene concentration. In conclusion, there were slight differences in bone measurements between red or 'Moonglow' tomato feeding, except for the significant reduction of one bone turnover marker. This suggests that a higher dose and longer intervention period may be needed to provide clinically important improvement against bone loss. However, significantly higher plasma lycopene followed ‘Moonglow’ feeding compared to red tomatoes, indicating its better bioavailability and demonstrating value for future research on health benefits from ‘Moonglow’ tomatoes. In addition, findings from this study provide support for the importance of exploring the potential prebiotic-like effect of tomatoes and the mechanisms associated with changes in gut bacteria.
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    Nutrient solution management for greenhouse tomatoes : a multiple-case study : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science at Massey University
    (Massey University, 2006) Xu, Minhua
    Nutrient solution released from hydroponic greenhouse operations has been considered as a potential pollution source by New Zealand regional authorities. The Management of Nutrient Solutions Released from Greenhouses: A Code of Practice (COP) is designed to assist New Zealand greenhouse growers in managing nutrient solution release in hydroponic systems to comply with The Resource Management Act 1991 (RMA) and regional resource plans prepared by regional authorities to ensure that their constituents act appropriately. A multiple-case study was designed to investigate the nutrient solution management and disposal practices of New Zealand hydroponic greenhouse tomato growers and, further, to investigate whether or not these practices meet the guidelines set out in The Management of Nutrient Solutions Released from Greenhouses: A Code of Practice. Three hydroponic greenhouse properties that represent the current New Zealand greenhouse tomato industry were selected as case studies. How the greenhouse growers manage nutrient solution in these greenhouses was investigated by interviewing the growers. The results show that none of the case study growers fully met the guidelines given in the COP. However, recirculating growers manage nutrient solution better than do the run-to-waste grower in terms of reducing nutrient solution discharge frequency. They release less volume of nitrogen into the environment per 1000 kg of tomato produced in their recirculating growing systems. The research results indicate that high-technology recirculating grower could better satisfy the requirements set out in the COP. Low-technology run-to-waste growers are unlikely to meet those requirements due to their system design. Therefore, adopting a recirculating growing system is considered as a trend of the industries in the future.
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    A study of the influence of excess concentrations of certain salts on the growth and development of glasshouse tomato plants, with special reference to the specific ion effects of theses salts : a thesis presented in partial fulfilment of the requirements for the degree of Master of Horticultural Science at Massey University, New Zealand
    (Massey University, 1964) Fisher, Keith James
    The yield and quality of fruit obtained from a glasshouse tomato crop is determined by the genetic make-up of the variety and the environment in which the crop is grown. The closer the environment to the optimum for the variety concerned, the closer the genetic limits will be approached. The environment can be divided into two parts - the above ground environment and the below ground environment. The below ground environment affects yields and quality through three primary factors: (a) Moisture availability. (b) Nutrient availability. (c) Physical condition of the soil. High levels of soluble salts in the soil can so influence these three factors that plant growth and development can be greatly depressed. With glasshouse tomatoes, depressions due to changes in the physical condition of the soil have not been reported, and are, in fact, not likely to occur. Under glasshouse conditions, the development of high concentrations of soluble salts results from the excess use of fertilizers and not from natural processes. Over a period of years, high fertilizer rates, unless combined with adequate management techniques, will build up the salinity to a critical level. This build up results from the carry over of unused fertilizers at the end of the season, due to excessive applications of fertilizers to the soil, and also from the use of fertilizers containing one ion which is not absorbed by the plants to any extent. [From Introduction]
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    Assessing the effect of plant surface on the predatory ability of Orius vicinus : a potential biological control agent of the tomato-potato psyllid (Bactericera cockerelli) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Zoology at Massey University, Palmerston North, New Zealand
    (Massey University, 2019) Gamarra Landa, Abel
    The tomato-potato psyllid (TPP), Bactericera cockerelli (Sulc), is a pest to solanaceous crops (e.g. potato, tomato, peppers, and eggplant) and is associated with economically important plant diseases. Subsequently, chemical control is the preferred management option. However, chemical reliance is associated with a host of issues. The development of biological control methods is vital to implementing Integrated Pest Management (IPM) programs as an alternative to broad-spectrum insecticide usage. The predatory bug Orius vicinus (Ribaut) is a potential biological control agent that is capable of consuming all nymphal life stages of TPP. In order to be a commercially viable management option, potential biological control agents of TPP have to cope with the different morphological plant features of the pest’s wide range of host plants. Tomato and capsicum plant surfaces were selected as the experimental surfaces for my thesis because they differ significantly in their substrate morphology. Tomato plant surfaces can be a hostile environment for potential biological control agents due to the negative effect tomato trichomes have on their foraging performance. Alternatively, because capsicum plant surfaces are virtually void of trichomes they appear to be more suitable for effective biological control agent deployment. I exposed the predatory bug to a variety of TPP nymph densities (10, 20, 30 and 40 individuals) in order to determine the functional response of O. vicinus. Furthermore, the predatory bug was exposed to all five TPP nymphal stages simultaneously. The predatory performance of O. vicinus was also assessed on experimental arenas varying in complexity (leaflet vs. small plant environments). The functional response was determined to be Type II on both plant surfaces. Nymph consumption at higher prey densities (30 and 40 nymphs) was significantly greater on capsicum than on tomato. Nymph consumption at lower prey densities (10 and 20 nymphs) was only significantly greater on capsicum when the complexity of the experimental arena increased from leaflet to small plant. The influence of O. vicinus in nymph dispersal was also assessed. My results revealed that the presence of O. vicinus increased the dispersal of nymphs to lower leaf surfaces and that nymph dispersal was significantly greater on capsicum than on tomato. TPP nymph size preference by O. vicinus was determined in my study. I established that the predatory bug is capable of killing all nymphal stages. My study strongly indicated that the predatory bug is more likely to target and consume medium (3rd instars) and large nymphs (4th and 5th instars) over small nymphs (1st and 2nd instars). I investigated the behaviour of O. vicinus adults and TPP nymphs during their interactions via video recordings. The predatory bug spent a significantly greater amount of time investigating TPP nymphs on capsicum than on tomato. There was significantly higher number of attacks recorded on capsicum. The greater killing percentage on tomato suggests that the defensive capabilities of TPP nymphs appear to have been negatively affected by the tomato substrate. The results from my study indicate that augmentative releases of O. vicinus, in the presence of smaller TPP nymphs, could be a viable biological control option on capsicum plants. However, the predatory bug will likely struggle if deployed on tomato plants. Future studies should be conducted in settings such as open field or glasshouses using multiple predatory bugs in the presence of susceptible life stages to assess augmentative release efficiency.
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    The effects of high conductivity liquid feeds on the yield and quality of outdoor grown tomatoes : a thesis presented in partial fulfilment of the requirements for the degree of Master of Horticultural Science in Vegetable Production at Massey University, Palmerston North, New Zealand
    (Massey University, 1993) Fadallan, Edgardo F
    Studies were conducted to evaluate the effects of high conductivity liquid feeds applied using drip irrigation on the yield and quality of outdoor grown tomatoes. Seed of the tomato cv. Extase were propagated in cell trays. During propagation the seedlings were fed using a stock solution containing 100 ppm nitrogen, 34 ppm phosphorous and 100 ppm potassium. The transplants were planted out on 3 December 1991 in the Karapoti Sandy Loam soil at the Plant Growth Unit, Massey University. The spacing used was 150 cm between the rows and 60 cm 2 in the row. A base maintenance dressing of Nitrophoska (12-16-10) fertilizer was applied at a rate of 500 kg per hectare banded 20 cm on either side of the row prior to planting. There were 3 conductivity treatments of 2, 4, and 6 mS cm-1 and a control treatment. A randomized complete block design was used with 4 blocks and 12 plants per plot. The 3 conductivity treatments were based on a standard greenhouse liquid feed, while the control plant received water only. Irrigation requirements were calculated based on a crop factor, area per plant and potential evapotranspiration. Conductivity treatments oommenced at the stage were 50% of the plants had commenced flowering on the first truss. Conductivity treatments were applied every 2 days for 2 hours regardless of rain, while control plants were irrigated with tap water when soil moisture deficits exceeded 28 mm day-1 except when rainfall immediately followed the scheduled irrigation. Plants were trained to 2 stems. The second stem was produced from the leaf axil immediately below the first inflorescence. The Otaki system of training and supporting tomato plants was used with the first support attached 25 days after planting and thereafter every 30 cm. Plants were delateraled regularly and stopped by removing the terminal buds at 2 metres high. Leaf analysis was carried out on 2 occasions, 30 and 55 days after planting, while the conductivity of the soil solution was determined at final harvest. Yield data was collected for each truss on a per stem basis per plant. Fruit were weighed individually and also size graded to the accepted commercial standard. From these data the number and weight of marketable and reject fruits were determined. Fruit samples were taken for 6 consecutive weekly harvests for compositional analysis. Firmness, total solids, titratable acidity and total soluble solids were measured from sample fruits from each treatment. Increasing the conductivity of the liquid feed increased the concentration of nitrogen and potassium in the leaves 30 days after planting, while phosphorous and magnesium were not affected by the treatments. Calcium fell with each increase in conductivity. At the reproductive stage (55 days after planting) the nitrogen, phosphorous and potassium content fell with increasing conductivity over the range of control to 4 mS cm-1• Calcium and magnesium content also fell with increasing conductivity of the liquid feed. The conductivity of the soil solution increased as the conductivity of the liquid feed increased. As the distance from the dripper increased the conductivity of soil solution decreased. Tomato plants in this study supported an average of 13 trusses. There were 18 harvests where fruits were harvested at a commercial acceptable stage of maturity and a 19th harvest was used to remove all the remaining fruit on the plant. The main stem carried approximately 65% of the fruit load. Conductivity treatments had no effect on the number and weight of fruit of individual trusses on the main stem except for the 4 mS cm-1 treatment which had a higher number and yield of fruit in the third truss. No explanation can be offered for this effect. There were no differences between treatments in the number or yield of fruit per truss on the lateral stem. Neither the number or yield of marketable fruit or the total number or total yield of fruit at final harvest were affected by the conductivity treatments. There was however a trend for yield to decrease with the 6 mS cm-1 treatment. It is possible that if the experiment had been continued for a longer period a treatment effect on the number and yield of fruit may have been obtained. It was suggested that the heavy rain experienced during the experiment may have delayed the occurrence of a yield reduction. Although there was no significant effect of conductivity on fruit size, the number of fruit in the two largest size grades tended to be highest for the control plants, while the 6 mS cm-1 treatment had the smallest number of fruit in these size grades. This is further evidence that the conductivity treatments tended to have an effect on fruit size and thus yield. The main cause for fruits to be rejected was due to fruit cracking, which usually occurred when harvesting preceded heavy rainfall. The occurrence of blossom end rot was low since both rainfall and the regular application of liquid feeds did not place the plants under a fluctuating moisture stress. Overall there were very few rejects. The conductivity treatments increased titratable acidity above that of control plants, but there were no difference between the conductivity treatments. Over time titratable acidity of the fruit declined and this may have been associated with either a seasonal effect or the position of the fruit on the stem. Total solids was increased as the concentration of the liquid feeds increased. The percentage of total solids allocated to structural material fell as the concentration of the liquid feed increased. This suggests that the increase in the total solids was due to an increase in the soluble solid component. There was no effect of conductivity on fruit firmness, however firmness fell from an initial value at harvest 1. Total soluble solids of the fruit increased with each increase in conductivity. Over time the trend was for soluble solids to fall slightly up to harvest 5 with a marked decline occurring at harvest 6. As improvements in fruit flavour are associated with increases in titratable acidity, total solids and total soluble solids the conductivity treatments used in this experiment were successful in improving this aspect of fruit quality. This was achieved without any decrease in yield. As suggested however, a trade off between quality and yield may have occurred if the experiment had been continued for a longer period of time. This research suggests that the use of trickle irrigation to supply high conductivity liquid feeds to field grown tomatoes has the potential to significantly improve fruit flavour.
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    An evaluation of pest and disease control practices in field process tomatoes in Hawkes Bay and opportunities for improved pest management : a thesis in partial fulfilment of the requirement for the degree of Master of Horticultural Science at Massey University
    (Massey University, 1992) Bland, Susanne
    The spray practices of seven process tomatoes growers in the Hawkes Bay were evaluated during the 1990/1991 season by analysis of spray diaries, field surveys, and weather data. In very few instances were calendar spray systems, weather or insect thresholds used to determine spray scheduling. Use of monitoring and forecasting systems already available will help decrease the number of sprays applied providing adequate research is done to adapt them to local conditions. It is concluded that there is potential for pest management and integrated pest management systems to be introduced into the process tomato crops.
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    A study on the effects of low temperature pre-sowing treatments and ageing on the germination performance of different tomato seed lots : a thesis presented in partial fulfilment of the requirements for Master of Agricultural Science (Seed Technology) at Massey University,Palmerston North, New Zealand
    (Massey University, 1989) Ranganarasimhiah, Ramamurthy
    Although the total germination capacities were not significantly different, ten different tomato seed lots differed in their vigour. LTPST caused signifi­cant improvement in germination rate both in high and low vigour seed lots of different cultivars of tomato seeds tested without altering their germination potential. The degree of improvement in germination rate was positively related to the initial germination rate of the seed lots and it was even possible to predict the effectiveness of the treatment based on the initial T5O of un­treated seeds. Despite the treatment always causing a significant improvement in germination rate, the improvement in uniformity was lot-dependent and the treatment had little or no effect on initial seedling growth. Increased SMC and temperature caused rapid loss of viability and ger­mination rate during storage. The effectiveness of LTPST treatment before ageing differed with seed lot and subsequent ageing conditions used. The application of the LTPST after ageing restored the germination rate to that of unaged untreated seed but as expected had no effect on loss of viability. The survival pattern of tomato seeds under rapid ageing followed a normal distribution and parameters of survival curves were in agreement with the norms of the general viability model for orthodox seeds. On the basis of these results of LTPST on aged seeds, it is argued that factors affecting loss of seed vigour may be different from those causing loss of seed viability during storage.
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    A study of the alternaria leafspot complex on potatoes and tomatoes in the Manawatu : this thesis is presented as partial fulfillment of the requirements for the M. Agr. Sc. degree of Massey University College of the Manawatu.
    (Massey University, 1963) Hawthorne, Brian Tredinnick
    The fungus Alternaria (Macrosporium) solani is associated with a foliage disease of potatoes and tamatoes throughout the world. Although there are often several phases of attack on these hosts by the fungus e.g. tuber damage in the potato and seedling loss with tomatoes, the disease has been named on the basis of the foliage symptoms which are characteristic. Two names are commonly used (l) Target Spot (2) Early Blight, and of the two, 'Target sport' is the more descriptive since foliage lesions are circular to irregular dark brown areas with a very characteristic zonation effect due to a series of more or less concentric rings within the lesion. [From Introduction]
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    Photoreceptor cross-talk in UV-B photomorphogenesis in tomato (Solanum lycopersicum) : screening through phytochrome and cryptochrome mutants : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Biology at Massey University, Palmerston North, New Zealand
    (Massey University, 2017) Pabellon, Ivie V S
    Plant photoreceptors detect changes in the light environment and induce differential gene expression, resulting in the appropriate physiological and morphological responses. Under full sunlight, phytochromes, cryptochromes and the UV-B photoreceptor, UVR8 (UV-B RESISTANCE LOCUS 8), destabilize PHYTOCHROME INTERACTING FACTORS (PIFs) to inhibit elongation. PIFs are transcriptions factors that inhibit light-regulated genes, including auxin-related genes involved in cell elongation. In the shaded environment, the reduction in the spectral composition detected by the photoreceptors results in the activation of elongation and PIF activity. However, recent studies have shown that low levels of UV-B can still inhibit the elongation under shade. Most photobiology studies that investigated plant responses to shade have concentrated on the model species, Arabidopsis thaliana. In contrast, Solanum lycopersicum (tomato) is another model system, but few studies have investigated plant responses to shade in tomato due to its sympodial architecture and presence of internodes which A. thaliana lacks. In this study, phytochrome and cryptochrome tomato mutants were exposed to low levels of UV-B under photosynthetically active radiation (PAR) as background light to investigate the possible crosstalk between these photoreceptors and the UV-B photoreceptor of tomato in regulating hypocotyl or internode elongation. Out of all the multiple phytochrome and one cryptochrome mutants, phyAphyB2 mutant exhibited an impaired UV-B inhibition of internode elongation after three days of UV-B treatment. End-point PCR on the gene expression of PIF4 together with two UV-B responsive genes and genes involved in the catabolism of active gibberellin could not explain the impaired response of phyAphyB2. Nevertheless, physiological measurements indicate that phyA and phyB2 of tomato may be acting redundantly in mediating the UV-B induced inhibition of internode.
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    Planning and control of IPM for greenhouse tomato growers : processes used by expert consultants : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science in Agricultural Systems & Management at Massey University
    (Massey University, 1999) Singgih, Shinta Milasari
    Given the clean, green image used to promote New Zealand produce, greenhouse tomato growers are under pressure to shift from conventional pest control to more environmentally-friendly methods such as IPM. However, growers often lack the specific knowledge required to tailor IPM strategies to their properties. Greenhouse consultants with expertise in IPM may provide a valuable source of assistance in terms of IPM adoption. However, little is known about how expert greenhouse consultants conduct this task. This study investigated the processes used by expert greenhouse consultants to assist greenhouse tomato growers with the planning and control of IPM strategies. A Multiple case study research method was selected as the most appropriate method for meeting the study objectives. Following the review of the literature, two expert greenhouse consultants were selected, and the data were collected using semi-structured interviews, field observations, and relevant documentation. Qualitative data analysis techniques were used to analyse the data. The two consultants were found to use similar IPM consultancy processes which, for the purpose of this study, have been separated into the physical activities, and planning and control processes. Both consultants perform similar physical activities (telephone calls and visits) to those used by farm management consultants. However, the two consultants studied distinguish between planning and control purpose telephone calls and visits, which the farm management consultants do not. In addition, both consultants use additional communication tools during the control stage. Throughout the consultancy processes, rapport is considered important to enable a trusting relationship to be built between the client and the consultant. The study highlights the presence of three phases during the consultancy processes, which were not mentioned in other farm management consultancy literature. The "screening" phase is used to ensure the development of the client's favourable attitudes toward IPM in the planning process. The "provision of information" phase, which occurs throughout the processes, is critical due to the complex nature of IPM. The "validation" phase is used to confirm the existence of the problems in the control process. During the planning and control processes, the client and the consultant share several roles and responsibilities. As the clients own the problem, they are responsible for making the decisions, implementing the plans, and undertaking monitoring. In order to do this, the clients act as the information providers and receivers for the consultant. The consultant is responsible for understanding the clients' system, providing the information required by the clients and designing the preventative IPM strategies during the planning stage. At this stage, the consultant also provides a monitoring strategy and contingency plans to be used by the clients. During control, the consultant is responsible for validating and diagnosing existence of the problems, providing information about the causal effect of the problems and designing the curative IPM strategies to solve the problems. During the design phase, the consultant uses decision rules to modify his IPM template, according to the need of each client. Factors such as type of crop, greenhouse age, crop age, whitefly population levels, the ability to heat, season, stud height, and persistence period are mentally structured to come up with various Encarsia introduction rates. In contrast, the IPM manual suggests a single Encarsia rate is used for all situations. The Encarsia introduction rates comprise the initial and maintenance rates. Case Study One starts with low rates of Encarsia for 2-4 weeks, followed by increasing the rates. Case Study Two starts with high rates of Encarsia for 6-10 weeks, followed by reducing the rates. Introduction is discontinued when the sustainable level of whitefly parasitism has been achieved. A more detailed IPM manual which allows for the specific circumstances in greenhouse tomato growers' properties is required to assist growers in the adoption of IPM strategies Key words: consultancy, planning, control, IPM, greenhouse tomatoes, Encarsia formosa, multiple case studies.