Summary The response of tree growth to a change in temperature may differ in predictable ways. Trees with conservative growth strategies may have little ability to respond to a changing climate. In addition, high latitude and altitude tree growth may be temperature-limited and thus benefi tf rom some degree of warming, as opposed to warm-adapted species. Using data from 63 studies, we examined whether trees from different functional groups and thermal niches differed in their growth response to a change in growth temperature. We also investigated whether responses predicted for a change in growth temperature (both reduced and elevated) were similar for increased temperatures by repeating the analysis on the subset of raised temperature data to confirm the validity of our results for use in a climate-warming scenario. Using both the temperature-change response and the warming response, we found that elevated temperatures enhanced growth (measured as shoot height, stem diameter and biomass) in deciduous species more than in evergreen trees. Tropical species were indeed more susceptible to warminginduced growth declines than temperate or boreal trees in both analyses. More carbon may be available to allocate to growth at high temperatures because respiration acclimated more strongly than photosynthesis, increasing carbon assimilation but moderating carbon losses. Trees that developed at elevated temperatures did not simply accelerate growth but followed different developmental trajectories than unwarmed trees, allocating more biomass to leaves and less to roots and growing taller for a given stem diameter. While there were insufficient data to analyze trends for particular species, we generated equations to describe general trends in tree growth to temperature changes and to warming for use at large spatial scales or where data are lacking. We discuss the implications of these results in the context of a changing climate and highlight the areas of greatest uncertainty regarding temperature and tree growth where future research is needed.

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Differential responses to changes in growth temperature between trees from different functional groups and biomes: a review and synthesis of data

prediction from sequence, which is the topic of this volume. However, although it is generally considered that all of the information required for protein folding is encoded within the primary structure, deciphering this has proved to be far from simple. Consequently, this volume contains a higher proportion of theory and discussion and fewer practical methods than most of its sister volumes. The eighteen chapters build up an account of protein structure prediction from its basic principles, starting with the analysis of the primary structure by alignment with related sequences and the recognition of conserved patterns and of protein domains. This is followed by an excellent, concise discussion of secondary structure prediction, which leads into the development and application of more sophisticated methods to predict folding (including the formation of specific motifs such as loops and folds and homology modelling), membrane protein structure, active sites, and the docking of proteins with other proteins and with peptide ligands. Much of the work described is still undergoing development and is certainly not suitable for routine application by non-experts. However, there is no doubt about the potential importance of protein structure prediction for “post-genomic” studies and this volume provides an excellent account of the current status.

Crop production science in horticulture series.

SummaryTen mango cultivars of tropical and subtropical origin (Carabao, Kensington, Nam Dok Mai, Alphonso, Dashehari, Florigon, Glenn, Irwin, Haden and Sensation) were grafted onto cv. Kensington seedling rootstock and held at four day/night temperatures for 20 weeks (15/10°C, 20/15°C, 25/20°C and 30/25°C). Vegetative growth increased with increasing temperatures. All grew vegetatively at 25/20°C and 30/25°C. Cultivars which did not grow at 20/15°C were Carabao, Kensington and Dashehari. Cultivars Kensington, Nam Dok Mai, Alphonso, Florigon, Glenn, Irwin, Haden and Sensation produced flower panicles at 15/10°C. The rise in temperature increased the average number of growth flushes (in responsive cultivars) from 0.48 at 15/10°C to 3.21 at 30/25°C, and the number of leaves per growth flush (1.22 at 15/10°C to 13.63 at 30/25°C). Distribution of dry matter from new growth was mostly to the roots at the lowest temperature (95% at 15/10°C) and to the leaves (58%) at 30/25°C. The mean daily temperature for zero ...

Effect of temperature on growth, dry matter production and starch accumulation in ten mango (Mangifera indica L.) cultivars

SummaryModerate day/night temperatures (20/15° v. 15/10°C) increased vegetative growth and reduced flowering in the seven litchi cvs Tai So, Bengal, Souey Tung, Kwai May Pink, Kwai May Red, Salathiel and Wai Chee. At higher temperatures (25/20° and 30/25°C), vegetative growth was promoted further and flowering eliminated. Temperature also influenced the type of inflorescence formed. More leaves were formed on the panicles of trees growing at 20/15° than at 15/10°C. All terminal shoots on all cultivars produced panicles at 15/10°C. The relative order for the amount of flowering at 20/15°C was: ‘Wai Chee’>‘Salathiel’>‘Kwai May Pink’>‘Tai So’>‘Bengal’>‘Souey Tung’>‘Kwai May Red’. Cultivars which were vigorous at high temperatures produced fewer panicles at 20/15°C and fewer leafless panicles at 15/10°C. Only small differences were observed in the leaf water potential and the nutrient status of the shoots at different temperatures. Vigour and flowering of the cultivars in the glasshouse generally reflected fi...

Effect of temperature on growth and flowering of litchi (Litchi chinensis Sonn.) cultivars

The reproductive biology of the lychee

The effect of temperature on growth and dry matter production of lychee seedlings

The seasonal pattern of development in seven guava (Psidium guajava) varieties grown in subtropical coastal southern Queensland was investigated to test the hypothesis that the growth pattern of some varieties is more suited to this environment. Leaf initiation commenced 4 weeks after defoliation by spraying with urea dissolved in water (250 g/litre) in September and continued for 22 weeks. Floral bud emergence and fruit set began 4-8 weeks later and continued for most of the period of shoot growth. Fruit took 14 weeks to reach maturity and the last fruit was harvested in mid-June when the trees passed into winter dormancy. Varieties varied in time to maturity, although the patterns and levels of leaf initiation, flowering and fruit set were similar. Yields ranged from 68.8 to 138.7 kg/tree. Differences between the varieties in yield could not be attributed to any characteristic such as the rate, timing or duration of flowering, fruit set or fruit growth. There was no variety with a different growth pattern closely related to high yields under conditions at Nambour. However, some varieties appear more suited to this environment, since they set a heavier crop which ripened before fruit quality declines in winter.

The pattern of growth, flowering and fruiting of guava varieties in subtropical Queensland

Four lychee (Litchi chinensis) cultivars (Bengal, Gee Kee, Tai So and Wai Chee) were grown in subtropical coastal southern Queensland. Yields after 8 years varied from 0.1 to 28.5 kg/tree (equivalent to a maximum of 6.6 t/ha at a density of 230 trees/ha). Wai Chee was superior to Gee Kee under all conditions and to Bengal and Tai So when flowering was reduced after warm wet winters or when fruiting was reduced during hot, dry springs.

Growth and yield of lychee cultivars in subtropical Queensland

SummaryThe effect of branch cincturing at different stages of vegetative flush maturity on the growth and flowering of two litchi cultivars in subtropical Queensland was investigated. In cv Bengal there was a strong increase in flowering when a branch with dormant vegetative growth was cinctured and a smaller increase with a branch in early or late flush. Flowering was not improved with a branch in mid-flush. In cv Tai So there was a reduction in flowering when a branch in early flush was cinctured. Cincturing at any other stage had no significant effect on flowering. The proportion of young to mature leaves on the branches (as indicated by average leaf weight) decreased as the flushes matured. The responses at different stages of flush development is considered to be a reflection of this ratio at the time of cincturing and its influence on the relative accumulation of flower inhibiting and promoting substances above the cincture.

The effect of cincturing at different stages of vegetative flush maturity on the flowering of litchi (Litchi chinensi Sonn.)

The effect of cincturing on growth and flowering of three lychee (Litchi chinensis) cultivars (Bengal, Brewster and Tai So) was investigated at four sites in subtropical southern Queensland. Cultivars at these sites displayed a range in the level of natural vegetative dormancy in winter (38-95% of terminal branches) and flowering in spring (25-100% of terminal branches). There was an inverse relation (r= 0.093; P< 0.005) between the flowering response to cincturing and potential flowering as indicated by the flowering of the control trees; cincturing reduced flowering in those trees that would otherwise have flowered profusely in spring (70-100%). This occurred when the cincture healed prematurely to allow vegetative flushing in winter. Since these preliminary results suggest that some loss of yield may occur in years and cultivars with good flowering, further work is required before cincturing can be recommended as a standard horticultural practice in lychee cultivation.

C.M. Menzel

Papers

The effect of temperature on growth and dry matter production of lychee seedlings

The pattern of growth, flowering and fruiting of guava varieties in subtropical Queensland

Growth and yield of lychee cultivars in subtropical Queensland

The effect of cincturing at different stages of vegetative flush maturity on the flowering of litchi (Litchi chinensi Sonn.)

Effect of cincturing on growth and flowering of lychee: preliminary observations in subtropical Queensland.