A study on the physiology of root parasitism in sandal (Santalum album L.) was conducted by comparing a six-year-old sandal grown alone and along with a host (Casuarina equisetifolia). Although maximum haustorial connections were observed when grown along with the host, sandal formed haustorial connections with plants including grass up to a distance of 3 m. Anatomical studies on haustoria indicated a vascular connectivity between the host and sandal. While the haustoria functioned as a physiological unit supporting nutritional requirements of sandal, direct lumenlumen xylem connections between sandal and host were absent. Functional status of the haustorial connection was studied by radio-labelling the host (Casuarina) and nearby grass with phosphorus ( 32 P). Presence of translocated 32 P in sandal was noticed after six hours of labelling the host. 32 P activity was noticed from eight days up to 16 days after which then it started decreasing. Study with multiple hosts revealed that the extent of translocation from hosts to sandal varied from 28.9% (coconut + Casuarina + rubber as host) to 78.5% (Casuarina + rubber as hosts). Reverse translocation of 32 P from sandal to host was also observed. The study concludes that it is not necessary to plant the host along with the sandal as it is practiced presently.

The present study was carried out to analyse the effect of rate of growth on the wood quality of teak from samples collected from trees which were grown within India as well as from outside. Teak samples (basal discs) from 14 different locations viz. Nilambur, Malayattoor, Konni, Ranni, Vadavar (TN) and Betul (MP) within India and Myanmar, Thailand, Ghana, Benin, Cameroon, Sudan, Tanzania and Trinidad outside India were included in the study. To study the effect of growth rate on wood quality, the collected samples were classified as fast grown and slow grown based on their average ring width. Those samples having an average ring width C5 mm and those having an average ring width \5 mm were categorised into fast grown and slow grown respectively. The analysis on variation in wood physical, anatomical and biochemical properties between the two categories revealed that, fast grown samples were characterized with higher specific gravity, moisture content (air dry) and shrinkage compared to the slow grown, but properties like vessel diameter, vessel area, ray height, ray width and extractive content (%) was found to be significantly higher for slow grown samples. However, fast and slow grown teak showed similarity with respect to other properties such as heartwood content (%), heartwood colour and bark thickness.

In Kerala, a coastal land in India, Ginger is cultivated as a rainfed annual. The current study on morphological characters of seed rhizomes stored in Zero Energy Cool Chambers recorded a weight loss of 28% at three months after storage. The number of sprouting buds was maximum (12.25) in the seed rhizomes stored for three months. The dimensions of the bud measured at the varied periods of storage interval showed variation. The length of the bud increased from 0.847μm to 2.19 μm and the breadth reduced from 1.19 μm to 0.703μm in three months of storage. The current study provides the anatomical morphology of ginger seed rhizomes. Histochemical studies of seed rhizome for three months storage showed that the number of cork layers varied from 5–15, size of starch grain decreased on storage from 40 μm to 20 μm and the oil globules found inside the parenchymatous cells increased from 20 μm to 40 μm. These results will be helpful to understand the bud development of ginger seed rhizome during storage.

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