Andhra Pradesh, India
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Kalaji H.M.,Warsaw University of Life Sciences | Schansker G.,Avenue des Amazones 2 | Ladle R.J.,Federal University of Alagoas | Goltsev V.,Sofia University | And 25 more authors.
Photosynthesis Research | Year: 2014

The aim of this educational review is to provide practical information on the hardware, methodology, and the hands on application of chlorophyll (Chl) a fluorescence technology. We present the paper in a question and answer format like frequently asked questions. Although nearly all information on the application of Chl a fluorescence can be found in the literature, it is not always easily accessible. This paper is primarily aimed at scientists who have some experience with the application of Chl a fluorescence but are still in the process of discovering what it all means and how it can be used. Topics discussed are (among other things) the kind of information that can be obtained using different fluorescence techniques, the interpretation of Chl a fluorescence signals, specific applications of these techniques, and practical advice on different subjects, such as on the length of dark adaptation before measurement of the Chl a fluorescence transient. The paper also provides the physiological background for some of the applied procedures. It also serves as a source of reference for experienced scientists. © 2014 The Author(s).


Suresh K.,Directorate of Oil Palm Research | Nagamani C.,Directorate of Oil Palm Research | Ramachandrudu K.,Directorate of Oil Palm Research | Mathur R.K.,Directorate of Oil Palm Research
Photosynthetica | Year: 2010

The gas-exchange characteristics, leaf water potential and chlorophyll (Chl) a fluorescence of oil palm (Elaeis guineensis Jacq.) seedlings subjected to water stress and recovery were investigated in a greenhouse experiment. At 24 days after imposition of stress, leaf water potential in water-stressed seedlings was doubled compared to that of control and there was a drastic decline in gas-exchange parameters viz. photosynthesis, transpiration, and stomatal conductance. Water stress did not irreversibly affect gas-exchange parameters and quantum efficiency of photosystem II, as seedlings exhibited total recovery of photosynthetic apparatus by 12 th day of rehydration. These findings indicate that oil palm exhibits physiological plasticity to water stress during the seedling stage. © 2010 Springer Science+Business Media B.V.


Ravichandran G.,ICAR Central Potato Research Station | Ravichandran G.,Directorate of Oil Palm Research | Venkatasalam E.P.,ICAR Central Potato Research Station | Manorama K.,ICAR Central Potato Research Station
Indian Journal of Horticulture | Year: 2015

Potato microtubers produced from tissue culture were subjected to coating with three bio-polymers (chitosan, gelatin and chitin) in four doses. Gelatin at 0.75 and 1.00% is effective in reducing the storage loss considerably up to 125 days after harvest without affecting the germination. The storage losses were drastically reduced in gelatin and chitosan treated microtubers due to improvement in sprout thickness to the tune of 47 and 25 per cent when compared with control. The stand establishment of gelatin treated microtubers in the field was higher by 23 per cent over control which significantly resulted in higher yield by nearly 47 per cent than the untreated tubers. © 2015 Horticulture Society of India. All rights reserved.


Jayanthi M.,Directorate of Oil Palm Research | Mohan N.M.,Directorate of Oil Palm Research | Mandal P.K.,Directorate of Oil Palm Research
Journal of Plant Biochemistry and Biotechnology | Year: 2011

Direct embryogenesis without an intervening callus phase from cotyledonary nodes of germinated immature zygotic embryos of hybrids viz. DG1 and DG21 of oil palm (Elaeis guineensis) is reported here. Direct embryogenesis was achieved when the cotyledonary nodes of germinated immature zygotic embryos were cultured in dark for 8 weeks on Eeuwens media (Y3) supplemented with 40 μM 2,4-Dichlorophenoxyacetic acid (2,4-D), 40 μM α-Naphthaleneacetic acid (NAA), 10 μM 2,4,5-Trichorophenoxyacetic acid (2,4,5-T), 10 μM Thiadiazuron (TDZ), 10 μM 6-Benzyladenine (BA). The globular embryos with clear suspensor region appeared directly on the explants and multiplied. On subculture to fresh media, the other stages such as torpedo and heart shaped embryos were seen. On transfer to light in Y3 media containing BA (2 μM) and ABA (1 μM) they matured into complete plantlets. In 2% of the cultures secondary embryogenesis also was seen. Along with several other advantages of direct somatic embryogenesis this protocol opens up the prospect of genetic transformation in this important commercial crop. © 2011 Society for Plant Biochemistry and Biotechnology.


Saravanan L.,Directorate of Oil Palm Research | Chaudhary V.,Directorate of Medicinal and Aromatic Plants Research
Journal of Applied Horticulture | Year: 2012

Dichromia orosia (Cramer), a near monophagus pest was observed to cause severe defoliation to its host plant, anthmool (Tylophora asthmatica Wight and Arn.), an important medicinal plant used in Ayurvedic formulations to treat asthma world over. Biology and seasonal activity o. The pest was studied during 2009-10 at Anand, Gujarat. Though incidence was observed throughou. The year, however. The pest activity was more during July, August, December, January and February months. The pest completed its life cycle in 24.53±0.40 days (Eggs 3-4, larvae 10-14 and pupae 6-7 days). The longevity o. The male and female was 15.70±0.68 and 19.70±0.42 days, respectively. Each female laid an average of 178.5±17.66 eggs, mostly o. The under surface o. The leaves in 12.20±0.49 days of oviposition period. The larvae developed through fi ve instars in 12.9±0.35 days and pupal period lasted for about 6.8±0.11 days. Correlation of peak pest population periods with corresponding and previous Standard Meteorological Weeks (SMW) revealed that prevalence of maximum temperature (27.5-30.2°C) mean temperature 29.31 °C, high RH and low rainfall recorded in increase of larval population.


Behera S.K.,Directorate of Oil Palm Research | Shukla A.K.,Indian Institute of Science
Land Degradation and Development | Year: 2015

Land degradation is a global problem. Best management of degraded land can be done by evaluating the spatial variability of soil properties including chemical properties of degraded land and mapping such variations. Since, a significant portion of arable land in India is chemically degraded due to soil acidity; the present study was conducted to study the spatial variability of soil acidity (pH), electrical conductivity (EC), soil organic carbon (OC) content, exchangeable potassium (K+), calcium (Ca2+) and magnesium (Mg2+) contents in some cropped acid soils of India. A total of four hundred (one hundred from each series) representative surface (0-0.15m depth) soil samples were collected from arable soils representing four soil series namely Hariharapur, Debatoli, Rajpora and Neeleswaram situated in Orissa, Jharkhand, Himachal Pradesh and Kerala states of India, respectively, and were analyzed. Soil acidity (pH between 3.90 and 6.45) showed a low variability, in contrast to other soil properties, which showed moderate variability. The coefficients of variation varied from 32.4 to 74.3, 31.2 to 50.9, 45.6 to 100, 71.9 to 93.0 and 59.0 to 79.8% for EC (mean between 0.05 and 0.09dSm-1), OC (mean between 0.29 to 1.86%), exchangeable K+ (mean between 39.1 and 77.7mgkg-1), Ca2+ (mean between 148 and 293mgkg-1) and Mg2+ (mean between 111 and 191mgkg-1), respectively. Soil pH and OC content were positively and significantly correlated with exchangeable K+, Ca2+ and Mg2+ content. Geostatistical analysis revealed that the best fit models were gaussian, exponential and spherical for different soil properties with moderate to strong spatial dependency. © 2014 John Wiley & Sons, Ltd.


Suresh K.,Directorate of Oil Palm Research | Nagamani C.,Directorate of Oil Palm Research | Kantha D.L.,Directorate of Oil Palm Research | Kumar M.K.,Directorate of Oil Palm Research
Photosynthetica | Year: 2012

The leaf water potential, gas-exchange parameters and chlorophyll fluorescence were evaluated in five common oil palm (Elaeis guineensis Jacq.) tenera hybrids 913X1988, 1425X2277, 748X1988, 7418X1988, and 690X1988 under water deficit with an aim to identify hybrids which can cope up better under such conditions and understand possible differences among hybrids in relation to the physiological mechanisms triggered by water deficit. Our findings indicate oil palm hybrids 913X1988, 1425X2277, and 7418X1988 maintained higher leaf water potentials than the other hybrids. Hybrids 7418X1988 and 1425X2277 recorded lower stomatal conductance after water deficit, which resulted in higher intrinsic water-use efficiency. The excess light energy produced due to decreased photosynthesis in 7418X1988 and 690X1988 hybrids under water deficit was dissipated as heat by higher nonphotochemical quenching. The maximum efficiency of photosystem II was not affected, even after withholding water for 24 days, suggesting an increased efficiency of photoprotection mechanisms in all these oil palm hybrids. © 2012 Springer Science+Business Media Dordrecht.


Murugesan P.,Directorate of Oil Palm Research | Shareef M.,Directorate of Oil Palm Research | Haseela H.,Directorate of Oil Palm Research | Ravichandran G.,Directorate of Oil Palm Research
Indian Journal of Agricultural Sciences | Year: 2014

Seed dormancy is considered as a major cause for low and erratic germination in oil palm (Elaeis guineensis Jacq.) which affects quality planting material production. To alleviate the problem, fresh hybrid seeds were subjected to seven treatments, viz. T1-complete endocarp removal and de-operculum, T2 -chipping endocarp and de-operculum, T3-chipping endocarp and scarification of operculum with pile rod, T4-chipping endocarp and scarification of operculum with sand paper, T5-chipping endocarp and needle insertion in the operculum and T6-making crack at germ pore region of shell and T7-dry heat method (control) with an objective to achieve uniform, speedy and maximum seed germination. Results showed that endocarp chipping combined with de-operculum resulted in the highest germination (88%) and took 3, 4 and 8 days to initiate germination, 50% germination and final germination, respectively. Dry heat method took 11 and 12 days to initiate and 50% germination, respectively resulted in only 66.6% germination even after 20 days incubation. Dry heat method also required extra heat treatment at 40° C for 60 days. It is inferred that chipping combined with de-operculum could be substituted with dry heat method at commercial seed production centres to break seed dormancy. Laboratory scale seed chipping machine is developed for chipping the endocarp of seeds. Up-gradation of lab scale machine is envisaged to scaling up germinated seed supply in a short period of time.


Murugesan P.,Directorate of Oil Palm Research | Haseela H.,Directorate of Oil Palm Research | Gopakumar S.,Directorate of Oil Palm Research | Shareef M.V.M.,Directorate of Oil Palm Research
Indian Journal of Horticulture | Year: 2011

A dwarf American oil palm (Elaeis oleifera) germplasm accession planted at Field Gene Bank of Directorate of Oil Palm Research, Regional Station, Palode, Kerala state was studied for fruit, seed development and maturity. Seeds extracted during matured fruit development stages were tested for germination. The study revealed that the fruit has developed steadily in size and weight from anthesis (0.27 g) to 135 days after anthesis (DAA) (8.62 g). The embryo has matured at 78 DAA and shell became hard and lignified during 113 to 126 DAA. Low moisture content was recorded in mesocarp (29.5%), shell (12.5%), kernel (27.2%) and embryo (59.5%) at 135 DAA with high seed germination (44.4%). Mesocarp oil synthesis initiated (3.91%) at 65 DAA and elevated to 50.9% at 113 DAA onwards and peaked at 135 DAA. Surinam oleifera fruit bunches took about 4.5 months (135 DAA) for fruit ripening and harvestable maturity. These experimental results will be utilised for breeding and improvement of dwarf oleifera palm of Surinam origin.


PubMed | Directorate of Oil Palm Research and Indian Agricultural Research Institute
Type: Letter | Journal: Zootaxa | Year: 2015

A new species, Acria meyricki sp. nov. (Lepidoptera: Depressariidae: Acriinae) occurring on oil palm, is described from India. The status and nomenclature of the genus is reviewed and an annotated checklist of species is given. A key to the seven species known so far from the Indian subcontinent is provided.

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