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.
A young patch of mangrove on South-West coast of India is subjected to intense human interference. A succession pattern was in progress in the undisturbed areas, wherein, a monospecifically dominated Avicennia officinalis stand was facilitating an understorey of shade loving species like Bruguiera cylindrica and Excoecaria agallocha. On the other hand, those parts of the forest which were subjected to human interference, the retrogression of the ecosystem was at play. The canopy gaps so created were covered by Acanthus ilicifolius, a light demanding under-shrub species, forming a thick bed of 2-3 ft height entirely covering the forest floor, thus prohibiting the establishment of other tree species. However, undisturbed mangrove forest areas were devoid of this shrub species.
The allelopathic effect of Teak (Tectona grandis Linn.f.) fruit leachates on the germination and vigour characteristics of Rice (Oryza sativa Linn.) and Green Gram (Vigna radiata (Linn.) Wilczek) seeds was studied under laboratory conditions. The Rice and Green Gram seeds were soaked directly in the Teak fruit leachates of different days or in distilled water and subsequently wetted during germination with the leachate or distilled water. The germination characteristics of Rice and Green Gram seeds increased significantly due to the application of Teak fruit leachate. Largest effect was recorded generally due to first day’s leachate and the effect declined due to subsequent days’ leachate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.