[Potential geographical distribution of Pyrus calleryana under different climate change scena-rios based on the MaxEnt model]. / 基于MaxEntæ¨¡åž‹ä¸åŒæ°”å€™å˜åŒ–æƒ æ™¯ä¸‹çš„è±†æ¢¨æ½œåœ¨åœ°ç†åˆ†å¸ƒ.

To resovle the problems of in-situ conservation and resource utilization of Pyrus caller-yana, maximum entropy model (MaxEnt) and geographic information system (GIS) were used to predict the global ecological suitable region of P. calleryana in different climate scenarios based on 236 distribution data and 19 ecological factors. The results showed that the ecological suitable regions of P. calleryana were mainly concentrated in North America, Asia and other regions, with a total area of 1.6×107 km2. In China, the regions with high ecological suitability were Hunan, Hubei, Anhui, Jiangxi, Jiangsu, Zhejiang and Fujian provinces. The main factors affecting the geographical distribution of P. calleryana were mean annual temperature and mean annual precipitation, followed by the seasonality of temperature. The model simulations indicated that P. calleryana would have different suitable habitat areas and marginally suitable habitat areas in different climate scenarios. In terms of the spatial distribution of the potential habitat area, both the distributional range and the center of distribution of suitable and marginally suitable habitat area would shift from east to west. The suitable habitat area in North America and marginally suitable habitat areas in Europe would increase rapidly.

Teste de porta-enxertos intergenéricos para marmeleiros em condições de viveiro / Tests of intergeneric rootstocks for quinces in nursery conditions

Os marmeleiros sempre foram propagados comercialmente mediante o enraizamento de estacas. Devido ao baixo vigor das mudas, principalmente nos primeiros anos após o plantio, alguns trabalhos foram desenvolvidos no Brasil a fim de viabilizar a utilização do marmeleiro 'Japonês' (Chaenomeles sinensis Koehne) como porta-enxerto para marmelos. Os resultados foram satisfatórios, mas frente à falta de outras opções de porta-enxertos mais vigorosos para marmeleiros e devido a observações em viveiro e a campo do alto vigor dos porta-enxertos para pereira 'Taiwan Nashi-C' (Pyrus calleryana Decne) e 'Taiwan Mamenashi' (Pyrus betulifolia Bunge), objetivou-se, neste trabalho, verificar o crescimento de cultivares de marmeleiros ('Provence', 'Mendoza Inta-37', 'Portugal', 'Smyrna' e 'Japonês') enxertados sobre esses porta-enxertos, na fase de viveiro. Os marmeleiros foram enxertados pelo método de garfagem em mudas dos porta-enxertos 'Japonês', 'Taiwan Nashi-C' e 'Taiwan Mamenashi', mantidas em sacos plásticos (capacidade de 3 L de substrato), no período hibernal. Foram utilizados garfos com três gemas, coletadas de plantas-matrizes do Instituto Agronômico (IAC). O experimento foi realizado em viveiro telado (50% de luminosidade), sendo avaliados o comprimento e diâmetro do enxerto aos 60, 90, 120 e 150 dias após a realização da enxertia e a porcentagem de garfos brotados na última avaliação. Os porta-enxertos orientais de pereira apresentaram bons resultados na fase de viveiro, com 'Taiwan Nashi-C' destacando-se como porta-enxerto para os marmeleiros 'Smyrna' e 'Mendoza Inta-37', 'Taiwan Mamenashi' para o marmeleiro 'Smyrna' e 'Japonês' para o mesmo.

The quince tree has always been commercially propagated by cuttings. Due to the low vigor, mainly in the first years of the orchard, a series of works was developed in Brazil in order to enable the use of the Japanese quince tree (Chaenomeles sinensis Koehne) as a rootstock. The results were satisfactory but the lack of other options for more vigorous rootstocks for quince tree and the observations in the nursery and in the field of a higher vigor of the pear rootstocks 'Taiwan Nashi-C' (Pyrus calleryana Decne) and 'Taiwan Mamenashi' (Pyrus betulifolia Bunge), led us to verify the performance of quince cultivars grafted on 'Japonês', 'Taiwan Nashi-C', and 'Taiwan Mamenashi' rootstocks, in nursery conditions. The 'Provence', 'Mendoza Inta-37', 'Portugal', 'Smyrna', and 'Japonês' quinces were grafted using the cleft grafting method onto the 'Japonês', 'Taiwan Nashi-C', and 'Taiwan Mamenashi' seedlings and maintained in plastic bags (3 L capacity of substrate) in the dormant period. The scion sticks used had three buds each and were collected from mother plants at the Instituto Agronômico de Campinas (IAC). The experiment was accomplished at a nursery (50% light). The length and diameter of the grafts were measured at 60, 90, 120, and 150 days after the grafting and the percentage of sprouted grafts was evaluated after 150 days. The oriental rootstocks 'Taiwan Nashi-C' and 'Taiwan Mamenashi' presented good results at the nursery, with 'Taiwan Nashi-C' outstanding as rootstocks for 'Smyrna' and 'Mendoza Inta-37' quinces, whereas 'Taiwan Mamenashi' was the best rootstock for 'Smyrna' quince and 'Japonês' for 'Japonês' quince.