Orcharding the future: the influence of temperature on Australian pome fruit flowering

Flowering development of pome fruit trees is dependent on local environmental conditions. The main driver in the timing of pome fruit flowering is temperature. However, understanding of the effect of temperature at an individual bud scale, is limited. The main purpose of this research was to investigate the differences in green tip timing, one of the earliest stages of flowering development, between bud types and potential temperature drivers. Changes in climate conditions may influence flowering timing potentially leading to a rise in the variability of fruit maturation, increasing harvesting costs as more picks are required. In addition, greater variability can potentially affect cross-pollination as varieties that pollinate each other may have different flowering at different times, limiting pollination potential. Furthermore, a better understanding of the relationships between temperature and individual bud behaviour will assist in assessments of future impacts of climate change on timing of flowering. Data from three different types of buds from 'Cripps Pink' apple were collected for 2012 and 2013. The study sites, which represent different climatic conditions, were Applethorpe (QLD), Shepparton (VIC) and Manjimup (WA). Statistical tests were applied to the data sets to evaluate possible differences in green tip emergence between bud types, sites and years. The results showed that on average spur buds were the first to burst at all sites. These were closely followed by terminal buds and then axially buds. Comparing across locations buds in Shepparton and Applethorpe were first to burst in both years, and some days later those located in Manjimup. There were significant differences in the day-of-year when individual buds reached green tip between bud types, within and across sites. The length of the green tip phase also varied between buds, sites and years. There was a consistent relationship between date of green tip and winter temperature. Cooler sites, Shepparton and Applethorpe, had the earliest dates of green tip while Manjimup experienced warmer winter seasons and the latest dates of green tip. Likewise, the warmer winter season, 2013, experienced a delay in the day-of-year when buds reached the green tip phase in all locations compared with 2012. Similarly, the length of the green tip phases was longer for 2013 than 2012. The results from this study help to further elucidate the relationships between winter temperatures and green tip in 'Cripps Pink' apple. Understanding these relationships is essential for the identification of potential impacts that future climate change may have on apple production in Australia

Elevation and latitude drives structure and tree species composition in andean forests: results from a large-scale plot network

Our knowledge about the structure and function of Andean forests at regional scales remains limited. Current initiatives to study forests over continental or global scales still have important geographical gaps, particularly in regions such as the tropical and subtropical Andes. In this study, we assessed patterns of structure and tree species diversity along ~ 4000 km of latitude and ~ 4000 m of elevation range in Andean forests. We used the Andean Forest Network (Red de Bosques Andinos, https://redbosques.condesan.org/) database which, at present, includes 491 forest plots (totaling 156.3 ha, ranging from 0.01 to 6 ha) representing a total of 86,964 identified tree stems ≥ 10 cm diameter at breast height belonging to 2341 identified species, 584 genera and 133 botanical families. Tree stem density and basal area increases with elevation while species richness decreases. Stem density and species richness both decrease with latitude. Subtropical forests have distinct tree species composition compared to those in the tropical region. In addition, floristic similarity of subtropical plots is between 13 to 16% while similarity between tropical forest plots is between 3% to 9%. Overall, plots ~ 0.5-ha or larger may be preferred for describing patterns at regional scales in order to avoid plot size effects. We highlight the need to promote collaboration and capacity building among researchers in the Andean region (i.e., South-South cooperation) in order to generate and synthesize information at regional scale. © 2020 Malizia et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited