Forest Research Institute

About: Forest Research Institute is a facility organization based out in Dehra Dūn, India. It is known for research contribution in the topics: Population & Forest management. The organization has 5320 authors who have published 7625 publications receiving 185876 citations.

Somatic embryogenesis of Scots pine: cold treatment and characteristics of explants affecting induction

Abstract: This is the first report on Scots pine (Pinus sylvestris L.) somatic embryo plants regenerated and growing in a greenhouse. The present work focused on improving somatic embryogenesis of the species by studying the factors affecting culture induction. Developmental stage of explants that were immature female gametophytes, including the zygotic embryos with suspensor tissues, was investigated in detail. The genetic background of the material, cold treatments (14 d, 1 or 2 months at +5 °C) of cones including explants, as well as the plant growth regulator composition of the initiation medium, were also examined. When initiation of somatic embryogenesis was successful, the zygotic embryos in the explants were either proembryos or early embryos. Cold treatment of the cones had no significant effect on induction, nor were there any differences among the treatments with different duration, thus improving the practical applicability of the culture technique. The explants in cold-stored cones probably retained their initiation capacity due to the conversion of starch to sugars. This was observed as decreased number and size of starch grains in the megagametophytes compared with the controls. The seed family and the medium significantly affected induction success, the medium with auxin (9.1 or 13.6 μM 2,4-dichlorophenoxyacetic acid) and cytokinin (2.2 μM 6-benzylaminopurine) being better than the medium with cytokinin (5 μM 6-benzylaminopurine) alone. The significance of the genetic background of the explants and the initiation medium indicate that it might be possible to improve the initiation rates by using explants from controlled crossings between competent genotypes, and by developing more specific media for important seed families.

Diurnal changes in leaf gas exchange characteristics in the uppermost canopy of a rain forest tree, Dryobalanops aromatica Gaertn. f.

Abstract: Dryobalanops aromatica Gaertn. f. is a major tropical canopy species in lowland tropical rain forests in Peninsular Malaysia. Diurnal changes in net photosynthetic rate (A) and stomatal conductance to water vapor (g(s)) were measured in fully expanded young and old leaves in the uppermost canopy (35 m above ground). Maximum A was 12 and 10 micro mol m(-2) s(-1) in young and old leaves, respectively; however, because of large variation in A among leaves, mean maximum A in young and old leaves was only 6.6 and 5.5 micro mol m(-2) s(-1), respectively. Both g(s) and A declined in young leaves when T(leaf) exceeded 34 degrees C and leaf-to-air vapor pressure deficit (DeltaW) exceeded 0.025, whereas in old leaves, g(s) and A did not start to decline until T(leaf) and DeltaW exceeded 36 degrees C and 0.035, respectively. Under saturating light conditions, A was linearly related to g(s). The coefficient of variation (CV) for the difference between the CO(2) concentrations of ambient air and the leaf intercellular air space (C(a) - C(i)) was smaller than the CV for A or g(s), suggesting that maximum g(s) was mainly controlled by mesophyll assimilation (A/C(i)). Minimum C(i)/C(a) ratios were relatively high (0.72-0.73), indicating a small drought-induced stomatal limitation to A and non-conservative water use in the uppermost canopy leaves.

Human recreation affects spatio-temporal habitat use patterns in red deer (Cervus elaphus).

Abstract: The rapid spread and diversification of outdoor recreation can impact on wildlife in various ways, often leading to the avoidance of disturbed habitats. To mitigate human-wildlife conflicts, spatial zonation schemes can be implemented to separate human activities from key wildlife habitats, e.g., by designating undisturbed wildlife refuges or areas with some level of restriction to human recreation and land use. However, mitigation practice rarely considers temporal differences in human-wildlife interactions. We used GPS telemetry data from 15 red deer to study the seasonal (winter vs. summer) and diurnal (day vs. night) variation in recreation effects on habitat use in a study region in south-western Germany where a spatial zonation scheme has been established. Our study aimed to determine if recreation infrastructure and spatial zonation affected red deer habitat use and whether these effects varied daily or seasonally. Recreation infrastructure did not affect home range selection in the study area, but strongly determined habitat use within the home range. The spatial zonation scheme was reflected in both of these two levels of habitat selection, with refuges and core areas being more frequently used than the border zones. Habitat use differed significantly between day and night in both seasons. Both summer and winter recreation trails, and nearby foraging habitats, were avoided during day, whereas a positive association was found during night. We conclude that human recreation has an effect on red deer habitat use, and when designing mitigation measures daily and seasonal variation in human-wildlife interactions should be taken into account. We advocate using spatial zonation in conjunction with temporal restrictions (i.e., banning nocturnal recreation activities) and the creation of suitable foraging habitats away from recreation trails.