The environment after seed set can negatively affect seed vigour. In New Zealand, pea (Pisum sativum L.) seed field emergence rate is estimated by a formula incorporating results from the germination test and two vigour tests: the electrical conductivity (EC) test: the hollow heart (HH) test. Vigour testing results of seed lots of mid-season pea cultivars, produced in five New Zealand regions (Masterton, Blenheim, Christchurch, Ashburton and Timaru) in four seasons (2001-2, 2002-3, 2003-4 and 2004-5), were obtained to determine variation in vigour among regions of production and among cropping seasons, and to identify whether climate data (monthly maximum, mean and minimum temperatures, and rainfall totals) were associated with this variation. Seasonal variations occurred in both EC and HH, and regional variations were also found for both vigour factors. These variations were significantly associated with February temperature: generally, the higher the temperature, the lower the seed vigour. Linear regression equations, derived from the significant relationships, were applied to the past twelve season's climate data to predict potential differences in seed vigour among the five regions. Predicted EC and HH significantly differed among regions. Thus, it should be possible to select a region of production which would have a lower risk of producing pea seed lots with low vigour.

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The effects of hormonal treatment for fruit setting on the occurrence of locule browning fruits were investigated in the tomato cultivar 'Super Yubi'. Plants were cultured in half- and full-strength Enshi solution. Flowers were sprayed with Tomatlane (chloxyfonac: 196 or 49ppm) with or without 15ppm GA_3 at anthesis. When plants were treated using 49ppm chloxyfonac with 15ppm GA_3, the number of abnormal fruits with locule browning and small holes at the blossom-end increased in plants cultured in either nutrient solution. The numbers of locules and sepals in these abnormal fruits were larger than those of normal fruits, though these numbers were not changed by cultural or hormonal treatments. Combined treatment with a low concentration of chloxyfonac (auxin-like substance) and GA_3 increased both the occurrence of a small hole at the blossom-end and locule browning. There seemed to be a close relationship between locule browning and blossom-end hole formation, which may be an important factor contributing to locule browning.

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This paper presents a study conducted to find the possibility of using near infrared spectra and partial least squares to determine COD, ammonia, total nitrogen and moisture content in pig waste, all in the same measurement. Further the study attempts to use non-standard sample presentation in order to determine the necessity of standard sample holders. The results show that a beaker of 100 ml and diameter 5 cm can be used for sample presentation in spectra taking under reflectance mode for pig wastewater. The spectra taken this way gave R^2 values above 0.8 for COD, NH_3 and T-N. The R^2 for moisture content was 0.7212. It is concluded that NIR has good potential for determining COD, NH_3 and T-N simultaneously for pig waste. The moisture content determination still needs standard sample holder or very low sample volume (bellow 5 ml in a 100 ml beaker).

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The effects of pollination methods on seed formation of white- and red-stem type water convolvulus (Ipomoea aquatica Forssk.), especially red-stem type, were investigated. Seven accessions of red-stem type from Thailand and two cultivars of white-stem type from Japan were used. Pollination methods were comprised of open-pollination (control), self-pollination (hand pollination of the same plant on anthesis date), cross-pollination (hand pollination between different plants on anthesis date), and bud-pollination at 1, 3, or 5 days before anthesis (DBA). In bud-pollination anthers were removed at 1, 3, or 5 DBA and mature pollen from the same plant was used for pollination. Seed formation was measured at about 60 days after pollination (DAP). The percentages of seed formation in red-stem type after cross-pollination were higher than that in self-, open-, or bud-pollination. Average seed formation of the red-stem type in cross-pollination was about 86.4%, but the values in self-, open-, and bud-pollination were 61.5, 52.1, and 25.7%, respectively. The lowest seed formation was observed in bud-pollination. Though 25.7% seeds were formed at 1 DBA, no seeds were formed at 3 or 5 DBA. In every pollination method, seed formation of the white-stem type was higher than that of the red-stem type. The average seed formation of the white-stem type in open-, self-, and cross-pollination was 89.9, 100, and 100%, respectively. From these results, it was proved that red-stem type has poorer seed formation compared to white-stem type. However, seed formation in red-stem type was increased by cross-pollination.

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This study was undertaken to clarify the influence of leaf number on the fruit quality and mineral composition in Earl's melon plants. Sugar content was higher as number of leaves increased. Phosphorus content in the first leaf on bearing branch significantly increased thirty days after fruiting when number of main stem leaves was over ten. Potassium content in the first leaf on bearing branch in treatment without pinching was about 1.8% higher than other treatments. Calcium content in the first leaf on bearing branch in treatment, where number of main stem leaves was over ten, decreased forty days after fruiting. In order to improve fruit quality, it is necessary to leave appropriate number of leaves.

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This study was undertaken to clarify the flower sex expression in balsam pear (Momordica charantia L.) flower buds. When treated with Ethrel at a concentration of 50 ppm in both 'Abashi' and 'Nishaku', pistillate flower differentiation was accelerated by a small majority. However, two cultivars were less sensitive to growth regulator than other Cucrubitiaceae vegetables. 'Abashi,' when given a low-temperature, short-day treatment, and 'Nishaku,' when given a high-temperature, natural day length treatment, exhibited similar results, but the effect was not great. Enhanced pistillate flower differentiation was observed in 'Nishaku' given 50% defoliation treatment, but the degree of enhancement was not pronounced. Although Ethrel treatments at low concentrations and defoliation enhanced pistillate flower differentiation in some cultivars, the effect was limited. These results described above indicate that balsam pear has an uncommon mechanism for flower-bud differentiation.

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A study was conducted to contribute to stable year-round supplies of winged bean (Psophocarpus tetragonolobus (L.) DC.). Two types of cultivars were tested to find the effects of the concentration of a nutrient solution, the number of watering, and bed position on yield in hydroponics using pumice medium. The yield and quality of 'Asuparaingen' were higher than 'KUS-12'. The optimal concentration of the nutrient solution is around EC 1.5 dS/m and the optimal number of watering is twice a day. Yield also increased in beds on the east and west sides, which were exposed to more abundant sunlight, with markedly higher yields on the east side. Shatter was observed during the peak summer, when no bean could be harvested. The period of no harvest was prolonged when the bean plants were treated with higher concentrations of the nutrient solution.

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This study was conducted to investigate the effect of purple non-sulfur bacterium application on the growth and quality of spinach and komatsuna as common leafy vegetables. Freeze dried purple non-sulfur bacterium (PTBP) was used for the investigation. The PTBP application promoted the growth of top part of spinach and root of komatsuna and increased total sugar, chlorophyll and carotenoid contents. However, the increasing of total sugar and carotenoid by the PTBP application was not recognized when sterilized soil was used in spinach cultivation. Therefore, it has been found that the PTBP application in sterile soil tended to show different effects on spinach compared to its application in non sterilized soil. This indicated that the effect of PTBP application might have interacted with soil microorganisms.

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