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Allocation dynamics of stored starch plays essential roles in the development and growth of trees. Previous studies focused on the dynamics and the characteristics of starch in autotrophic trees. However, although starch granules have been detected in the organs or tissues of some parasitic plants, studies on the allocation dynamics and roles of storage starch in them are limited. Therefore, we determined and estimated the allocation dynamics and roles of starch in Santalum album Linn., a hemiparasitic tree, using morphological and physiological methods. Our findings showed abundant starch in the stem and root of S. album at the early seedling stage. Although S. album seedlings attached to the host showed no significant changes in starch levels throughout the experiment, unattached and host-removed seedlings exhibited a gradual decrease in the starch content over time. When the starch content of unattached seedlings was less than 1%, they started to die. Starch accumulated to high levels in developing and active haustoria; however, starch levels were low in the inactive haustoria. The present study suggests that starch may provide energy to seedlings that have no host, allowing them to survive during the unattached phase, thus increasing their chance to attach to host roots by extending their survival duration. In addition, we speculate that storage starch is potentially involved in the development of haustoria and in the physiological processes of S. album related to the absorption and transportation of water and nutrients from its host.

We studied the effects of different culture media on the growth of India sandalwood (Santalum album L.) seedlings in Zhanjiang, Guangdong Province in southern China. Five different growth substrates, lateritic subsoil, burnt soil, agricultural soil, peaty soil and coconut dust, were used as the basic culture materials and seven different treatments of composition were used as potting media. Kuhnia rosmarinifolia Vent. was used as a primary host plant for all treatments. Statistically significant differences were found between treatments in respects of survival rate (p < 0.001), height (p < 0.001), ground diameter (p < 0.001) and biomass (p = 0.002), as well as for quality index (p = 0.001) of S. album seedlings after 6-month growth in containers with different culture media. Among all treatments, the treatment combining burnt soil, peat and coconut dust in a weight ratio of 1:1:1 plus 2% calcium super-phosphate as basal manure achieved the best performance for most of the seedling growth parameters, including survival rate (98%), height (35.81 cm), ground diameter (0.56 cm), biomass (4.46 g) and quality index (0.65), followed by the treatment using only burnt soil plus 2% calcium super-phosphate as the culture medium (survival rate 86%, height 29.23 cm, ground diameter 0.48 cm, biomass 3.36 g and quality index 0.52), while the treatment using only lateritic subsoil plus the basal manure as the medium obtained the poorest results in survival rate (38%), height (12.04 cm), ground diameter (0.19 cm), biomass (0.26 g) and quality index (0.043). Increasing the proportion of lateritic subsoil in the medium when mixed with peat and coconut dust did not show statistically significant differences in survival, height, ground diameter, biomass nor in quality index. In consideration of cost, using burnt soil plus 2% calcium super-phosphate as basal manure may be the optimum culture medium for large-scale production of Indian sandalwood seedlings in Guangdong, southern China.

As one of the most expensive wood trees, Ormosia henryi has been planted more than 1000 mu in South China now. A mass of Ormosia henryi leaves was naturally abandoned and degradable so that the resources were wasted. Therefore, in order to overcome the negative effects, Py-GC/MS was used to analyze the extractives of Ormosia henryi leaves. Relative content of each component was determined by area normalization. The benzene/ethanol extractives contain 57 compounds namely thiophene, 2,5-dibutyl-, tetradecanal, rishitin, pyrrole, pyridine, 5-hexyl-2-methyl-, pyrene, hexadecahydro-, p-menth-8(10)-en-9-ol, cis-, pentadecane, oleic acid, octane, octadecanoic acid, nonanal, naphthalene, decahydro-, naphthalene, 1,2,3,4,4a,5,6,8a-octahydro-4a,8-dimethyl-2- (1-methylethenyl)-, hexanoic acid, 3-hexenyl ester, (z)-, hexadecanoic acid, methyl ester, hexadecanoic acid, 2-hydroxy-l-(hydroxymethyl)ethyl ester, hexadecanoic acid, heneicosane, glycerin, and so on. So the rare medicinal materials and rare spice is rich in the extractives of Ormosia henryi leaves. The byproducts can be used as not only top grade cosmetics and skin care, but also bio- energy.