Sanjay Gairola - Academia.edu (original) (raw)

Papers by Sanjay Gairola

Randles Nursery,Durban, South Africa(Received 3 July 2014; accepted 25 November 2014)Vascular epi... more Randles Nursery,Durban, South Africa(Received 3 July 2014; accepted 25 November 2014)Vascular epiphytes live non-parasitically on other plants and are a distinctive and intergral componentof tropical forests. There is a general lack of studies examining epiphyte diversity in urban settings.The aim of this study was to document the diversity of epiphytes on host trees in the eThekwiniMetropolitan Area (EMA). In addition, the number of individuals of each epiphyte, host treecircumference at breast height and height were recorded. In total, 30 epiphyte species from 12 familieswere recorded, with most epiphyte species belonging to the Moraceae (n = 8) and Araliaceae (n = 5).A total of 34 host species from 15 families were recorded. These numbers did not increase whenconsidering herbarium material within the EMA sensu stricto. The highest epiphyte richness (n = 13)was reported on the palm Raphia australis. The high number of both alien host and epiphytic taxa areof concern. More studies ...

The Indian Forester, 2013

The Sunderdhunga valley harbors a number of medicinal plants used by the local people in differen... more The Sunderdhunga valley harbors a number of medicinal plants used by the local people in different purposes. A total of 76 ethnomedicinal plants have been enumerated in the present communication with correct binomials, family, life form, local name along with detailed ethnomedicinal uses. These species belong to 27 families and 56 genera. Out of total species recorded, 82% belongs to only 11 families, on the other hand 48% of total families represented by single species. Fifteen of the recorded species are categorized under different threat category, constituting about 20% of total species. Major cause of depletion of these species is over exploitation of the wild populations and illegal trade. Important measures required to conserve the biodiversity of the valley include documentation of the traditional ecological and remedial knowledge of the locals for sustaining future generation and motivation to cultivate rare or threatened species in nearby villages.

In many species, seeds with different sizes show diverse responses in their requirements for temp... more In many species, seeds with different sizes show diverse responses in their requirements for temperature and light for optimal germination. In this study, the effect of seed size (i.e., small and l...

Native grasses have the potential to be good candidates for fodder production and restoration or ... more Native grasses have the potential to be good candidates for fodder production and restoration or rehabilitation of degraded desert rangelands because of their palatability, nutritive value and adaptation to local environmental conditions. Most of the information about germination levels and speed of grasses seeds is based on Petri dishes experiments conducted under control conditions, rather in soils under field or nursery conditions. Indeed, few studies compared the germination of native plants under controlled conditions and in potted soils under field conditions. Here, we compare the germination of six grasses native to the Arabian deserts under different temperatures (15/25, 20/30 and 25/35 °C) and light (12 hrs light/12 hrs dark and continuous darkness) regimes in Petri dishes incubated in growth chambers and potted soils in an open site. Five of the analyzed species showed significantly greater germination in Petri dishes than in potted soils, while the sixth species (Aristida...

Journal of Arid Environments

Trees, Forests and People

Environmental Monitoring and Assessment

It has been established that resurvey of historical vegetation stands, even those not marked perm... more It has been established that resurvey of historical vegetation stands, even those not marked permanently, could foster our understanding of vegetation dynamics and changes in structure and composition over time. However, such studies are poorly available, particularly in remote landscapes of the Indian Himalaya. There exists a complete lack of resurveys, which has limited our ability to provide reliable evidence of changes over the decades. This study, for the first time in the Indian Himalaya, considered repeat surveys (nearly after 25 years) of vegetation stands in eleven forest communities of the buffer zone of NDBR (Nanda Devi Biosphere Reserve). Thirty historical forest stands, earlier studied in 1988–1990, were revisited during 2012–2014 and investigated using the same survey methods as used in the previous study. We found that previously reported dominant tree species, i.e., Alnus nepalensis, Acer cappadocicum, Quercus floribunda, Quercus semecarpifolia, Hippophae salicifolia, and Betula utilis, in nine out of eleven communities in the study area are continuing to exhibit dominance in the community. However, a significant increase in species richness and density in the seedling and sapling layer in Quercus floribunda, Quercus semecarpifolia, Rhododendron arboreum, and Abies pindrow is indicative of the ongoing process of change in forest composition. The compositional features of plant communities, when analyzed through Community Change Sensitivity (CCS) approach, identified Quercus floribunda, mixed Quercus—deciduous spp., Hippophae salicifolia, and Abies pindrow as the most change-sensitive communities in the study area and thus can be prioritized as the long-term ecological monitoring sites in the west Himalaya to understand intensity and patterns of changes. The potential changes based on the ecological information from two time period compositional data sets, having conservation and management implications, should be accommodated in the long-term perspective plans of the reserve.

Arid Land Research and Management

Abstract Information about seed source effects on germination and stress tolerance of the multipu... more Abstract Information about seed source effects on germination and stress tolerance of the multipurpose exotic Prosopis juliflora (Sw.) DC. is scarce. Here, we investigate the influence of seed provenance on salinity tolerance and germination requirements of P. juliflora. Seeds collected from saline (SH) and nonsaline (SNH) habitats were treated with different NaCl concentrations (0–600 mM) and incubated in two photoperiods and three thermoperiod regimes. The results showed that tolerance of seeds from SH and NSH to salinity depended on thermoperiod, but not on photoperiod or interactions between photoperiod with both NaCl and thermoperiod. Germination of seeds from the two habitats did not differ significantly across thermoperiods in control and 200 mM NaCl. However, in 400 and 600 NaCl, germination was significantly greater for seeds from NSH than those from SH at lower thermoperiod in both light and darkness; whereas the reverse was true at higher temperatures in light. Seed germination of both habitat types was significantly lower at higher than at both lower and intermediate thermoperiods in all salt solutions, but the difference was more pronounced at higher salinities. Germination recovery failed in darkness at all photoperiod and thermoperiod regimes. Partial germination recovery happened only for seeds that failed to germinate in 400 mM NaCl in light and intermediate thermoperiod. Germination was significantly faster for seeds from SH than from NSH at higher salinities. The results emphasize the importance of considering the seed source for the restoration of salt-affected lands.

Botany

In the present study, salt tolerance during germination of A. lagopoides was tested for fresh see... more In the present study, salt tolerance during germination of A. lagopoides was tested for fresh seeds collected from three different maternal habitats under three thermoperiods and two light regimes. Additionally, the ability of non-germinated seeds at the different NaCl conditions to recover their germination in distilled water was tested. The results showed a significant effect of seed source, temperature and salinity and some of their two- and three-way interactions on, final germination and recovery percentage. The seeds from non-saline provenances had the highest germination (ca. 79%) under the 35/25°C temperature regime while the lowest germination (ca. 21%) was recorded in seeds from saline conditions under the 25/15°C treatment. Additionally, the germination decreased from seeds incubated under non-saline solutions - control (0 mM NaCl) and warmer conditions (35/25°C) to saline solutions (100, 200, 400 and 600 mM NaCl) and colder conditions (15/25°C). The highest recovery perc...

Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology

Abstract Light and growth-promoting compounds, such as gibberellic acids (GA3), are among the mos... more Abstract Light and growth-promoting compounds, such as gibberellic acids (GA3), are among the most important factors that can break physiological seed dormancy. Here, we investigate the effects of GA3 and light on germination of five species of Resedaceae that are known to have different levels of physiological dormancy. Seeds were incubated at 20/30 °C in both 12-hr photoperiod and complete darkness. To study the effect of growth hormone on germination, seeds were soaked for 24 h in different concentrations of GA3 before sowing. The annuals (Reseda aucheri and Oligomeris linifolia) and the perennial Ochradenus arabicus had deep physiological dormancy, and exogenous application of GA3 enhanced their germination in the light, but not in darkness; few or no seeds germinated in the dark in these species. Ochradenus aucheri and O. baccatus had intermediate and non-deep dormancy, respectively, and application of GA3 enhanced their germination in both light and darkness. Germination of the annual species was much slower than that of the shrubby perennials. Overall, these results indicate that conditions under which seed developed, matured and stored on maternal plants as well as incubation conditions should be taken into consideration when assessing germination behavior of the perennial species of Resedaceae.

Plant Diversity

Ex situ conservation in seed banks is a potential complementary conservation strategy for native ... more Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species. It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby preserves genetic and species diversity for future use. We evaluated ex situ storage potential of eight halophytic species from deserts in the United Arab Emirates (UAE) by studying seed germination. Specifically, we examined the germinability of freshly collected seeds and seeds stored for three years in a seed bank. We also examined the effect of light conditions on fresh and stored seed germination. Fresh seeds of seven of the eight species tested had a higher germination rates under 12/12 h light/dark fluctuations than did those exposed to total darkness. Storage reduced light sensitivity in Halocnemum strobilaceum, Suaeda aegyptiaca, Salsola drummondii and Salsola imbricata, but increased the requirement for light in Arthrocnemum macrostachyum. In Anabasis setifera, storage decreased germination percentage when there was a 12-hour light/dark fluctuation, but increased germination rate when exposed to the dark treatment. Storage significantly reduced germination in both the light/dark and dark treatments in Suaeda vermiculata and S. aegyptiaca. Germination speed also responded differently to storage; whereas Timson's index significantly increased in A. macrostachyum and H. strobilaceum, it significantly decreased for S. drummondii, S. aegyptiaca and S. vermiculata. Germination of these species at a range of temperatures requires further testing; additionally, we strongly suggest that these laboratory findings be complemented by field studies.

Frontiers in Plant Science

Physiology and molecular biology of plants : an international journal of functional plant biology, 2018

The biotechnology of desert plants is a vast subject. The main applications in this broad field o... more The biotechnology of desert plants is a vast subject. The main applications in this broad field of study comprises of plant tissue culture, genetic engineering, molecular markers and others. Biotechnology applications have the potential to address biodiversity conservation as well as agricultural, medicinal, and environmental issues. There is a need to increase our knowledge of the genetic diversity through the use of molecular genetics and biotechnological approaches in desert plants in the Arabian Gulf region including those in the United Arab Emirates (UAE). This article provides a prospective research for the study of UAE desert plant diversity through DNA fingerprinting as well as understanding the mechanisms of both abiotic stress resistance (including salinity, drought and heat stresses) and biotic stress resistance (including disease and insect resistance). Special attention is given to the desert halophytes and their utilization to alleviate the salinity stress, which is on...

South African Journal of Geomatics

Nordic Journal of Botany

We aimed to determine the ecological role of three seed morphs observed for the first time in a d... more We aimed to determine the ecological role of three seed morphs observed for the first time in a desert population of Lotononis platycarpa (Fabaceae), with respect to their germination requirements. Seeds sorted by seed coat colour (olive green, orange and brown) were germinated under laboratory conditions under two photoperiods (12/12‐h light and continuous dark) and three alternating temperature regimes (15/25, 20/30, 25/35°C). We found that the three distinct seed types differ in their seed mass, germination percentage and speed of germination. Overall, the light‐incubated seeds germinated with higher percentages than seeds in the total darkness. Furthermore, seeds with orange coat germinated with higher percentages at 15/25 and 25/35°C (up to 60%, for both) and significantly faster than the other two colour morphs. Our results suggest an adaptive significance of seed colour heterogeneity in the harsh desert habitat inhabited by the study species.

Journal of Plant Growth Regulation