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Karst rocky desertification (KRD) is a typical fragile ecological environment with its key and difficult management point being vegetation restoration. Therefore, it is crucial to determine the adaptation mechanisms of suitable plants for ecological restoration in KRD areas. D. odorifera is a tall leguminous, woody plant with high medicinal and wood value. This study aimed to explore the adaptation strategy of the D. odorifera root system to the shallow karst fissure-soil (SKF-S) habitats. The growth, biomass, spatial root distribution, morphological characteristics, and physiological responses of D. odorifera seedlings under different treatments were studied in pots simulating SKF-S habitats. Through the experiments conducted, the following conclusions were obtained: (I) D. odorifera enhanced its ability to acquire limited resources through an allocation adjustment strategy (adjusting the biomass allocation strategy, increasing the root shoot ratio, prioritizing organ leaves and 3-level roots), which effectively offset some of the adverse effects; (II) with an increase in the stress severity, D. odorifera improved its resource acquisition adaptive strategy by reducing the root diameter and increasing the contact area with soil; (III) the spatial development characteristics of its root system were mainly manifested in the ability to grow vertically, deeper, compared to a horizontal extension; (IV) D. odorifera did not passively endure rocky desertification stress but actively improved its metabolism through root metabolic activity and SOD enzyme activity.

Inferential models are usually used to evaluate the effect of winter warming on range expansion of insects. Generally, correlative approaches used to predict changes in the distributions of organisms are based on the assumption that climatic boundaries are fixed. Spodoptera exigua Hübner (Lepidoptera: Noctuidae) overwinters as larvae or pupae in China regions. To understand the climate change impacts on overwintering of this species in regions of China, CLIMEX and Arc-GIS models were used to predict possible changes of distribution based on temperature. The climate change projection clearly indicated that the northern boundary of overwintering for S. exigua will shift northward from current distribution. Thus, the ongoing winter warming is likely to increase the frequency of S. exigua outbreaks.

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Yu, S., Yin, L. and Mu, S. 2010. Discovery of an antifreeze protein in the leaves of Ammopiptanthus nanus. Can. J. Plant Sci. 90: 35Á40. Overwintering plants produce antifreeze proteins (AFPs) that allow plants to survive under freezing or subfreezing conditions. Ammopiptanthus nanus (M. Pop.) Cheng f. grows in the desert of Xinjiang, P.R. China, and our objective was to determine if its survival was dependent on AFP and to identify the protein. Using anion exchange and gel filtration, the AFP was extracted, isolated and purified from cold-acclimated A. nanus leaves. The thermal hysteresis activity (THA) of the antifreeze proteins was measured by differential scanning calorimetry. The THA of the AFP was 0.468C when the concentration of the protein was 20 mg mL (1 . The molecular weight of a band was about 119.24 kDa in SDS-PAGE gel. We detected (PB0.05) the ribuloseÁ1,5-bisphosphate carboxylase/oxygenase large subunit by analyzing the 119.24 kDa protein using the Waters SYNAPT TM high definition mass spectrometry (HDMS TM ) System. Our results indicate that there is an AFP in A. nanus leaves, and that it may play a vital role as a defence against the cold climate, thus increasing the chances for survival of A. nanus in its desert habitat. Ils ont mesure´l'hyste´re´sis thermique (HT) de la prote´ine par calorime´trie diffe´rentielle a`balayage. L'HT de la prote´ine s'e´levait a`0,46 8C, a`une concentration de 20 mg par ml. Le poids mole´culaire d'une des bandes avoisinait 119,24 kDa en e´lectrophore`se sur gel de polyacrylamide en pre´sence de SDS (SDS-PAGE). En analysant la prote´ine de 119,24 kDa avec le syste`me Waters SYNAPT TM HDMS TM , les auteurs ont de´cele´(P B 0,05) la grosse sous-unite´de la ribulose-1,5-biphosphate carboxylase/oxyge´nase. Les re´sultats indiquent donc que les feuilles d'Ammopiptanthus nanus renferment bien une prote´ine antigel qui pourrait jouer un roˆle crucial dans la de´fense de la plante contre le froid et accroıˆtre ses chances de survie dans le de´sert.