Phytomorphology and Nutrient Dynamics of Mulberry Leaf

Background: The present study on the topic “Phytomorphology and nutrient dynamics of mulberry leaves” revealed high variability among mulberry varieties. Internodes were largest in variety Tr4 (6.06%). Actual leaf area was high in variety S146 (275.57 cm2). Numbers of leaves per meter branch was largest in variety S1531 (20.9). During 5 periodic sampling from sprouting to maturity average fresh and dry leaf weight of 100 leaves was high (197.93g) and (60.24g) respectively during 5th sampling. Average moisture content was high (83.41%) during 1st sampling highest average chlorophyll content (SPAD value) was also observed during 4th sampling (40.01%). Acidity was also high in variety Tr4 during maturity. Sugar content was high in variety T1 (3.66%) during 1st sampling (15 days). Starch and ash content was high in variety S1708 (43.06%) and (32.50%) during 5th sampling. Nitrogen and protein content was highest in variety S1608 (5.02%) and (31.56%) respectively during 1st sampling. Methods: In the field-laboratory investigation was conducted at Division of Sericulture, Division of Biochemistry and Plant Physiology, SKUAST-J, Chatha, during spring 2013. Ten mulberry varieties T1, Tr4, V1, S146, S1708, S799, S1608, S1531, S41 and Sujanpur were evaluated for phytomorphological and nutrient dynamic studies. The experiment was laid in complete randomized block design with three replicates. Each variety was taken as treatment and observations were recorded after 15 days interval upto 75th day after sprouting. Result: On the basis of current result, parameter observed fluctuations from the date of sprouting till maturity. Varietal response to periodic sampling too varied. Protein decreases age along with sugar, nitrogen. On the contrary starch, biomass, ash, chlorophyll shown a gradual increase. This information can be utilized to harvest a particular type of leaf for a particular age and rearing.

Litter Production and Nutrient Dynamic on a Moso Bamboo Plantation following an Extreme Disturbance of 2008 Ice Storm

Ice storm is known to play a role in determining forest succession and litter dynamics constitute an important aspect of nutrient cycling in forest ecosystems. However, ice storm effects on amount and pattern of litterfall are not clearly understood. We investigated litter production and litter leaf nutrient dynamic in a moso bamboo plantation in China following an extreme disturbance of ice storm in 2008. The litterfall in on-years was significantly lower than in off-years. Ice storm caused total litterfall increasing from 16.68% to 35.60% and greatly disturbed the litterfall peak rhythm especially in the on-year. The litter leaf nutrient concentrations at two latitudes significantly fluctuated after ice-snow disaster in 2008, litter leaf stoichiometric traits indicated that litter leaf chemistry showed more easily decomposition with higher C/P ratio, N/P ratio, and lower C/N ratio. It is clear from this study that litterfall restoration dynamic would result in long-term changes in litter nutrient cycling and may help predicting below ground carbon dynamic in future research as well as subtropical forest inventories following extreme disturbance.

TROPHIC AND NUTRIENT DYNAMIC ASPECT OF AQUATIC MICROBIAL ECOLOGY

This paper gives a chronological review on our understanding in the role of heterotrophic bacteria in trophic and nutrient dynamic aspects of aquatic microbial ecology. Traditionally, the role of heterotrophic bacteria was known as decomposer only. Later studies revealed that bacteria could be the food for several grazers especially, nano-, micro- and mesozooplankton. Now, it is clear that heterotrophic bacteria channel the energy and matter to higher trophic level via microbial and metazoan food chains. Previously it was argued that dissolved organic carbon (DOC) is the prime limiting factor for fueling the energy and nutrient in aquatic ecosystem. However, emerging experimental evidences suggest that enrichment of plant nutrients such as phosphorus (P) stimulates bacterial growth. These suggest accumulation or organic carbon and other important nutrients in aquatic ecosystem, which are funneled in presence of limiting nutrients phosphorus. Moreover, recent studies showed that material transfer efficiency from bacteria to higher trophic level may depend on species composition of mesozooplankton. These discoveries established that bacterial primary production contributes substantially in secondary production, implying that contrasting to their tiny form bacteria play much important role in trophic and nutrient dynamics aspects of aquatic ecology. Key words: Heterotrophic bacteria; Trophic dynamics; Nutrients; Mesozooplankton DOI: 10.3126/eco.v17i0.4097Ecoprint An International Journal of Ecology Vol. 17, 2010 Page: 9-16 Uploaded date: 28 December, 2010