Effects of temperature on early development of the New Zealand geoduck Panopea zelandica (Quoy & Gaimard, 1835)     

Shaneel S. Sharma  Andrea C. Alfaro  Norman L. C. Ragg  Leonardo N. Zamora 《Aquaculture Research》2020,51(2):751-760

Ambient seawater temperature is an important factor during the early life stages of marine invertebrates. Temperature is often manipulated in hatcheries to shorten the incubation period before the larval rearing phase. In this study, the effect of temperature on the early development of the geoduck Panopea zelandica was investigated over a 48‐hr period to identify the optimum temperature for fertilization and development in a controlled environment. Eggs and sperm collected from broodstock were exposed to ten temperatures ranging between 11.8 and 23.7°C, and fertilization and subsequent development were monitored over 48 hr. Highest percentages of fertilization were achieved at 23.7°C, which was the highest temperature tested in this study. However, the development of P. zelandica embryos was greatly hindered at temperatures >18.5°C due to a range of abnormalities arising from uneven cell division and cellular blebbing. All larvae died at the highest temperature of 23.7°C within 48 hr of exposure. The combined fertilization success and embryo development data indicate that 18.5°C is the optimal temperature for incubating P. zelandica embryos under hatchery conditions.  相似文献   

Operationalizing a Framework for Assessing the Enabling Environment for Community Forest Enterprises: A Case Study from Nepal     

Sharma  Bishnu Prasad  Lawry  Steven  Paudel  Naya Sharma  McLain  Rebecca  Adhikary  Anukram  Banjade  Mani Ram 《Small-Scale Forestry》2020,19(1):83-106

Small-scale Forestry - We demonstrate how Baynes et al.’s (Glob Environ Change 35:226–238, 2015. https://doi.org/10.1016/j.gloenvcha.2015.09.011) framework can be operationalized as a...  相似文献   

Foliar fertilization: possible routes of iron transport from leaf surface to cell organelles     

Hina Malhotra  Sandeep Sharma  Prem S. Bindraban 《Archives of Agronomy and Soil Science》2020,66(3):279-300

ABSTRACT

Iron (Fe) plays a pivotal role in plant nutrition as well as human health. Foliar application is being adopted as an economic, targeted and environment friendly alternative over soil fertilization. However, dependency of foliar fertilization on crop species, environment, Fe compound and Fe status of plant makes it a complex practice. Though a large body of evidence is available on Fe movement from root to shoot, very little is known on its movement from the leaf surface (extracellular) to various organelles (intracellular). This article presents possible pathways of foliar-fed Fe including crossing leaf physical barriers to reach the apoplast, crossing the plasma membrane, moving through plasmodesmata, phloem loading and unloading and storage in intracellular compartments. We have also emphasized on various chelating agents present in intracellular environments along with membrane-bound proteins aiding in Fe movement. Further, genes involved in Fe uptake and transport from leaf surface are discussed. At organelle level, presence of importer/exporter in outer membranes or bound Fe (Fe(II) to Fe(III)) form needs to be identified. The long-distance transport of Fe in phloem supports the existence of unknown oxido-reductases. The understanding of Fe mobilization pathways from foliage to sink tissues might also assist in molecular biofortification.  相似文献   

Recent trends in muskmelon (Cucumis melo L.) research: an overview     

Hament Thakur  Shikha Sharma  Manisha Thakur 《The Journal of Horticultural Science and Biotechnology》2019,94(4):533-547

Muskmelon is a warm season old-world cucurbit species which belongs to family Cucurbitaceae. It has served as a wonder crop since ancient times, as the leaves and seeds of it are used to treat hematoma, and the stems to reduce hypertension. For decades, it has played key roles in the field of plant molecular biology and plant physiology, serving as an excellent model plant for investigating the phenomenon of sex determination and ripening processes. Elite varieties of melons carrying the wide potential to serve as more demanding to end user and against tolerance to drought condition and inferior lands, or diseases have been developed. Plant-breeding methods (conventional or molecular breeding) and transgenic technology are the only tools left, with which we can deploy to regenerate the elite varieties in melon fruits to meet the global demand for next decades. The development of plant biotechnological tools for melons offers the prospect to develop new varieties, more rapidly, avoiding natural genetic barriers. The use of these methods has extended to increase the genetic diversity by somatic hybridisation or gene transfer and to optimise conventional breeding programmes. In this review, we have focused on the status of crop improvement in muskmelon since a period of time for different traits like quality improvement, sex expression as well as resistances against biotic and abiotic stresses.  相似文献   

Origin and cytology of a novel cytotype of Allium tuberosum Rottl. ex Spreng. (2n = 48)     

Geeta Sharma  Ravinder N. Gohil 《Genetic Resources and Crop Evolution》2013,60(2):503-511

Naturally occurring/spontaneously produced polyploids with six/more genomes are rarely found in Alliums. A hexaploid form of Allium tuberosum with 2n = 48 chromosomes has been isolated for the first time amongst the open-pollinated seedlings of a hypotetraploid plant (2n = 4x = 31); latter being the seed-derived product of a normal tetraploid stock (2n = 4x = 32) growing in Jammu University Botanical Garden. Except for the guard cells and pollen grains that are of increased size, this form compared to its progenitor is dwarf, has smaller leaves and bears inflorescences with few flowers. This plant is also different from its progenitor in having nearly one-fourth (27.8 %) of its pollen mother cells (PMCs) with varying chromosome number viz. 27–64, with the remaining cells having somatic or double the somatic number of chromosomes. To assess the nature of hexaploid form, its chromosomes were studied for morphological details, putative grouping and pairing properties during reduction division. Morphological similarity in the chromosomes of the present cytotype and its progenitor, arrangement of 48 chromosomes in eight groups of six chromosomes each and presence of 21.88 % euploid cells with eight hexavalents pointed towards the autopolyploid nature of the present strain. Regarding the origin of this strain, observation made on the meiosis in the two sex mother cells of the progenitor provides some clues. In the later plant, presence of most of embryo-sac mother cells with 62 chromosomes that showed 31:31 segregations and existence of majority of the PMCs with 31 chromosomes exhibiting erratic segregations indicate that the hexaploid strain has probably originated as a result of the fusion of reduced male (n = 17) and unreduced female gamete (2n = 31).  相似文献   

Strategic use of Iranian bread wheat landrace accessions for genetic improvement: Core set formulation and validation     

Prashant Vikram  Jorge Franco  Juan Burgueo  Huihui Li  Deepmala Sehgal  Carolina Saint‐Pierre  Cynthia Ortiz  Vaibhav Kumar Singh  Clay Sneller  Achla Sharma  Maria Tattaris  Carlos Guzman  Javier Pena  Carolina Paola Sansaloni  Jaime Amador Campos Serna  Karthikeyan Thiyagarajan  Guillermo Fuentes Davila  Matthew Reynolds  Kai Sonder  Velu Govindan  Marc Ellis  Sridhar Bhavani  Mohammad R. Jalal Kamali  Mozaffar Roosatei  Sanjay Singh  Daisy Basandrai  Navtej Singh Bains  Ashwani Basandrai  Thomas Payne  Jos Crossa  Sukhwinder Singh 《Plant Breeding》2021,140(1):87-99

Iranian wheat landrace accessions (IWAs) were collected from country‐wide farm fields and market places in 1935 by a professor at the University of Tehran and shared with University of California at Davis, California. IWAs were further submitted to the genebank of International Maize and Wheat Improvement Center (CIMMYT), Mexico. 2,403 IWAs from CIMMYT’s genebank were assayed by DArT‐seq technology to assess genetic diversity. No apparent ecogeographic patterns related to genetic diversity were detected, probably due to long‐term transport and frequent interchange of landraces among farmers. A multivariate clustering procedure combining genotypic and phenotypic information was used in selecting a core‐set, which represented 15% of the hexaploid wheat accessions included in this study. This subset captured an estimated 93% of rare (frequency <0.05) alleles. Multisite phenotypic data (India, Mexico) validated the ability of the core‐set in detecting useful variants. Potential donor accessions for multiple traits (disease resistance, zinc concentration) were identified from the core‐set for wheat‐breeding. This report illustrates a breeder friendly robust core‐set formulation strategy for harnessing the useful genetic variation stored in the genebanks.  相似文献   

PHYSIOLOGICAL AND BIOCHEMICAL RESPONSES RESULTING FROM CADMIUM AND ZINC ACCUMULATION IN CARROT PLANTS     

Rajesh Kumar Sharma  Madhoolika Agrawal  Shashi Bhushan Agrawal 《Journal of plant nutrition》2013,36(7):1066-1079

The interactive effect of cadmium (Cd) and zinc (Zn) bioaccumulation on physiological and biochemical characteristics of carrot (Daucus carota L. var Pusa Kesar) plants grown with different levels of Cd and Zn was examined. The combined application of Cd and Zn (Cd+Zn) had synergistic and antagonistic effects at low and high concentrations, respectively, on Cd accumulations in plants, chlorophyll b, and photosynthesis and transpiration rates. Whereas both low and high Cd+Zn concentrations had synergistic effects on Zn accumulation, ascorbic acid, protein content, total phenols, peroxidase activity, chlorophyll a, total, carotenoids and stomatal conductance. Bioaccumulation of Cd had strong and negative relationships with measured physiological and biochemical parameters. The study further showed that Cd and Zn in combination have more toxic effects on carrot plants as compared to their individual treatments. This study concludes that interactive effects of Cd and Zn on test plant depend on their ratios present in plants.  相似文献   

RHIZOSPHERIC EFFECT OF VESICULAR ARBUSCULAR MYCORRHIZAL INOCULATION ON BIOMASS PRODUCTION OF RUTA GRAVEOLENS L.: A POTENTIAL MEDICINAL AND AROMATIC HERB     

Vipin Parkash  Ashok Aggarwal  Vipasha Sharma 《Journal of plant nutrition》2013,36(9):1386-1396

A bio-inoculation experiment was performed on Ruta graveolens L., known as “Garden Rue” seedlings for the biomass production. Seedlings were inoculated with single and in combined mycorrhizal treatments. All inoculated seedlings showed significant biomass production than control seedlings. The phosphorus (P) content was more in seedlings inoculated with consortium of three native VAM fungi followed by Glomus mosseae, Acaulospora laevis and Gigaspora gigantea alone treatments. The control seedlings had the least P content but root P content was more than shoot P content in all treatments. The biomass of shoot and root was also significantly more in seedlings inoculated with consortium followed by G. mosseae, A. laevis and G. gigantea alone treatment. The control seedlings again had low shoot and root biomass. The Biovolume index (B_i) was also high in all inoculated treatments than non-inoculated control but consortium treatment (7.98) had at par B_i than rest of inoculation treatments. The quality index (Q_i) value was also high in mixed consortium (1.42) and A. laevis treatment (1.42) each respectively than G. mosseae (1.38) and G. gigantea (1.29) treatments. Control seedlings had low value of Q_i (1.27). The present study indicates that G. mosseae, A. laevis, G. gigantea are the best strains of VAM symbionts when mixed together for inoculating the R. graveolens to get higher yield of biomass. A. laevis is also good strain of VAM fungi for the same purpose. The G. gigantea alone proved least effective strain for inoculation purpose in R. graveolens but when mixed together in consortium of native VAM fungi as described above executed good results for enhancing the biomass production.  相似文献   

EFFECT OF PACLOBUTRAZOL AND PUTRESCINE ON ANTIOXIDANT ENZYMES ACTIVITY AND NUTRIENTS CONTENT IN SALT TOLERANT CITRUS ROOTSTOCK SOUR ORANGE UNDER SODIUM CHLORIDE STRESS     

Dew Kumari Sharma  A. K. Dubey  Manish Srivastav  A. K. Singh  R. N. Pandey  Anil Dahuja 《Journal of plant nutrition》2013,36(11):1765-1779

The effects of paclobutrazol (PBZ) and putrescine (Put) on antioxidant enzymes activity, proline contents and nutrients uptake were studied on salt tolerant citrus rootstock sour orange. Six-month-old nucellar seedlings grown in pots and subjected to three levels of PBZ and two levels each of salinity and Put for 90 days. Seedlings treated with PBZ or Put alone or in combination had higher anti-oxidant enzymes activities, accumulation of proline and nutrients contents like potassium (K⁺) and calcium (Ca²⁺) under both saline and non-saline conditions. Further, application of PBZ or Put alone or in combination also reduced the accumulation of both Na⁺ and Cl^? ions in leaves and roots in NaCl stressed seedlings. A combined application of 250 mg L^?1 PBZ and 50 mg L^?1 Put proved to be more effective in improving proline and Ca²⁺ content and restricting accumulation of Na⁺ ions in leaf tissues.  相似文献   

SOIL POTASSIUM FRACTIONS IN RICE-WHEAT CROPPING SYSTEM AFTER TWELVE YEARS OF LANTANA RESIDUE INCORPORATION IN A NORTHWEST HIMALAYAN ACID ALFISOL     

Sandeep Sharma  Girish Chander  T. S. Verma  Sudhir Verma 《Journal of plant nutrition》2013,36(12):1809-1820

A long-term field experiment with rice-wheat cropping was started in the wet season of 1988 with four levels of lantana (Lantana camara L.) (0, 10, 20, and 30 Mg ha^?1 on fresh weight basis) and three tillage practices (No puddling, puddling, and soil compaction). From wet season of 1997, however, three tillage practices were replaced with three levels of nitrogen (N) and potassium (K) to rice (33, 66, and 100% of recommended) and 66% of recommended N, phosphorus (P), and K to wheat. Phosphorus was totally omitted for the rice crop. The recommended N and K for rice was 90 and 40 kg ha^?1, whereas the recommendations for N, P, and K for wheat were 120, 90 and 30 kg ha^?1. Organic amendments are known to improve soil productivity under rice-wheat cropping by improving physical conditions and nutrient status of the soil, but their availability is restricted. There is a need to identify locally available and cost-effective organic materials that have minimal alternate uses as fodder and fuel. We evaluated Lantana camara L. residues, a fast-growing weed in nearby wastelands, as a potential soil organic amendment. Among the different fractions of K, nonexchangeable K was dominant followed by exchangeable and water soluble K. The incorporation of lantana (10 to 30 Mg ha^?1) over the last 12 years has resulted in a significant build-up of all the K fractions, the maximum being in water-soluble K (10 to 32%) followed by exchangeable K (18 to 27%) and least in nonexchangeable K (5 to 7%) over no lantana incorporation. The increasing levels of these two inputs significantly and consistently increased ammonium acetate (NH₄OAc)- extracted K (available K) content in soil and also resulted in significantly higher accumulation of K by the crops during the years of experimentation. Among different K fractions, exchangeable K was observed to be the most important K fraction contributing towards wheat and rice yields as well as K accumulation by wheat and rice. Stepwise multiple regression equations indicated that exchangeable K was the most important variable contributing towards total variation in grain yield and K accumulation by wheat or rice.  相似文献