New Zealand Journal of Crop and Horticultural Science, 2003, Vol. 31: 221-233 Abstract Expression of phenolic compounds associated with constitutive and wound-induced resistance to Botrytis cinerea was studied in leaves of two kiwifruit cultivars, Actinidia chinensis 'Hort16A' and A. deliciosa 'Hayward'. Constitutive leaf resistance to B. cinerea was much greater in 'Hort16A' than in 'Hayward'. This resistance might be attributable, in part, to phenolic compounds, since phenolic extracts from non-induced 'Hort16A' leaves were significantly more fungitoxic than those from 'Hayward'. Fungitoxicity correlated positively with concentrations of three components in the phenolic fraction, one of which was identified as caffeic acid. Wounding and inoculation induced resistance in 'Hayward', but not 'Hort16A' leaves. Induction was accompanied by an increased concentration of a fourth component in the phenolic fraction, although this compound did not appear to be directly anti-fungal. This is the first study to examine the relationship between resistance against B. cinerea and phenolic compounds in leaves of the two main commercial kiwifruit cultivars, and results suggest that three phenolic compounds may contribute to constitutive resistance in 'Hort16A'.

There is renewed interest in fodder beet (Beta vulgaris L.) production in the South Island of New Zealand. However, recommended agronomic practices for maximising productivity and quality are limited. Two experiments investigating the effects of different rates (kg/ha) of potassium (K; 150 or 300), sodium (Na; 100 or 200) and chloride (Cl; 240) fertiliser application on fodder beet dry matter (DM) production, nutrient concentration and uptake were carried out at Southbridge (2011) and Bankside (2012), Canterbury, New Zealand. Final DM yield was unaffected by the treatments: averaging 32 t DM/ha at Southbridge and 21 t DM/ha at Bankside. However, there was a significant interaction between K and both Cl and Na, on DM yield at Southbridge. Specifically, yield increased to 38 t DM/ha with Na and decreased to 30 t DM/ha with Cl, in the presence of K. Application of K, Na, and Cl fertiliser increased the respective tissue mineral concentration and respective total uptake for both the bulb and shoot components. Potassium tended to depress crude protein, neutral detergent fibre and ash content of the bulbs and increase the metabolisable energy and soluble sugar. The combination of low fibre and high soluble sugar concentrations puts animals at risk of rumen acidosis. These results suggest that fodder beet crops subjected to high rate of soil and/ or fertiliser K should be supplemented with feed high in crude protein and fibre. Key words: Beta vulgaris L., agronomic practices, mineral concentration, mineral uptake, quality attributes.

Irrigation is likely to increase water losses from hillslopes, particularly on loess-derived soils with impeded drainage. This is important as irrigation of these soils in New Zealand is increasing. A field site was established to measure runoff from a pasture hillslope irrigated by a centre-pivot in South Canterbury. Between November and March, 161 and 199 mm of irrigation was applied, with 23% more at the bottom of the slope. Runoff varied with position in the hillslope, with 3.5 times from the bottom plot (52 mm) compared to the top. Over the length of the slope (40 m) this represents a potential loss of 9% of precipitation, or 21% of the irrigation. Evidence for saturation excess and infiltration excess runoff was observed, with antecedent soil moisture conditions being a key factor. Pasture production and water use efficiency (WUE) also varied with slope, the least (4.6 t DM/ha or 12 kg DM/ha/mm) observed at middle and most at the top of the slope (10.1 t DM/ha or 23 kg DM/ha/mm). This was likely due to a combination of differences in radiation and soil conditions. There was indication that pasture growth was limited by water availability at the top and potentially excess at the bottom of the slope. Our results indicate potential for improving irrigation practices.

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