The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Loraine U Kohorn - One of the best experts on this subject based on the ideXlab platform.
-
geographic variation in the occurrence and extent of sexual dimorphism in a dioecious shrub Simmondsia chinensis
Oikos, 1995Co-Authors: Loraine U KohornAbstract:Simmondsia chinensis (Simmondsiaceae), a dioecious desert shrub, varies throughout its geographic distribution in both the occurrence and the extent of sexual dimorphism present in secondary sex characteristics. Three desert populations showed significant morphological differences between sexes, while five populations in more mesic sites were sexually isomorphic. Females had larger leaves than males in two of the eight populations surveyed, and longer internodes in three populations. Females tended to branch more frequently, although this was statistically significant in only one population. At one desert site, male shrubs were taller and larger than females, while at a coastal site, sexes did not differ in gross morphology. The extent of sexual dimorphism appears to be associated with the potential evapo-transpiration of the environment, as the degree of dimorphism in leaf size was inversely correlated with the amount of rainfall during the growing season, and that of internode length was associated with large annual temperature fluctuations. It is hypothesized that selection for larger seed size, advantageous in more xeric environments, contributed to selection for larger vegetative features in females through allometric responses. The extent of dimorphism in internode length increased with mean female internode length, indicating that the dimorphism may have arisen through modifications in female morphology. Also, females tend to show greater variability in measured characters ; this differential variance could contribute to the evolution of sexual dimorphism in this species.
Manisha Mangal - One of the best experts on this subject based on the ideXlab platform.
-
Callus induction and plant regeneration from leaf explants of jojoba [Simmondsia chinensis (Link) Schneider]
Indian Journal of Biotechnology, 2013Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:An efficient micropropagation protocol involving callus induction and shoot regeneration has been standardized in Simmondsia chinensis, an oil yielding, medicinal and multi- purpose plant species. Higher percent of callus proliferation (97.3%) was obtained from leaf explants, taken from field grown mature plant, when cultured on MS medium supplemented with 2,4-D (2.0 mg L-1)+BAP (0.5 mg L-1)+CH (100 mg L-1) within 20-22 d of inoculation. The callus was yellowish green in colour and soft in texture. Further, optimum shoot regeneration was obtained from the leaf derived callus on MS medium fortified with BAP (2.0 mg L-1)+NAA (0.5 mg L-1)+GA3 (0.3 mg L-1). About 92% cultures responded with an average number of 9.1 shoots per culture. The shoots obtained via callogenesis were rooted on half-strength agar-solidified MS medium supplemented with IBA (1.0 or 2.5 mg L-1). The medium containing 2.5 mg L-1 IBA was the best for rooting of shoots. The rooted shoots were transplanted to soil with 75% success. The protocol will be of immense importance in rapid mass multiplication of elite germplasm, as well as for conservation of this important species. Keywords:
-
Biotechnological advances in jojoba [Simmondsia chinensis (Link) Schneider]: Recent developments and prospects for further research
Plant Biotechnology Reports, 2012Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:Jojoba (Simmondsia chinensis), is a medicinal and oil-yielding, multi-purpose species of the family Simmondsiaceae. The most valuable product of jojoba seed is the liquid wax or jojoba oil which is used extensively in the cosmetic and bio-fuel industry. Propagation of jojoba is possible using conventional methods, but it is time consuming and cumbersome owing to long rotation periods, male-biased population, and long flowering and seed set time. The development of an efficient regeneration system is a prerequisite for a number of biotechnological interventions for the improvement of jojoba, such as genetic transformation, production of useful metabolites in vitro, etc. During the past decade, therefore, several attempts have been made for in vitro propagation of jojoba. Organogenesis has been achieved in this species from mature as well as juvenile explants. Present communication reports an overview of the in vitro regeneration of jojoba via organogenesis and somatic embryogenesis. Factors affecting organogenesis as well as production of synthetic seeds using shoot tips and axillary buds have also been discussed; however, efforts need to be made to develop an efficient genetic transformation system in jojoba. The purpose of this review is to focus upon the current information on in vitro propagation and biotechnological advances made in jojoba.
-
assessment of genetic fidelity of micropropagated plants of Simmondsia chinensis link schneider using rapd and issr markers
Acta Physiologiae Plantarum, 2011Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:RAPD (random amplified polymorphic DNA) and ISSR (inter simple sequence repeat) markers were screened to test the genetic integrity of jojoba (Simmondsia chinensis) plants multiplied through axillary bud multiplication from nodal segments. The in vitro raised plantlets were maintained for up to 12 in vitro subcultures. During the study a total of 48 (32 RAPD and 16 ISSR) primers were screened, out of which 24 RAPD and 13 ISSR primers produced a total of 191 (126 RAPD and 65 ISSR) clear, distinct and reproducible amplicons. The amplified products were monomorphic across all the selected micropropagated plants and were similar to the mother plant. The micropropagation protocol developed by our group for rapid in vitro multiplication is appropriate for clonal propagation of jojoba. The outcome supports the fact that axillary bud multiplication can also be used as one of the safest modes for the production of true-to-type plants.
-
Assessment of genetic fidelity of micropropagated plants of Simmondsia chinensis (Link) Schneider using RAPD and ISSR markers
Acta Physiologiae Plantarum, 2011Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:RAPD (random amplified polymorphic DNA) and ISSR (inter simple sequence repeat) markers were screened to test the genetic integrity of jojoba (Simmondsia chinensis) plants multiplied through axillary bud multiplication from nodal segments. The in vitro raised plantlets were maintained for up to 12 in vitro subcultures. During the study a total of 48 (32 RAPD and 16 ISSR) primers were screened, out of which 24 RAPD and 13 ISSR primers produced a total of 191 (126 RAPD and 65 ISSR) clear, distinct and reproducible amplicons. The amplified products were monomorphic across all the selected micropropagated plants and were similar to the mother plant. The micropropagation protocol developed by our group for rapid in vitro multiplication is appropriate for clonal propagation of jojoba. The outcome supports the fact that axillary bud multiplication can also be used as one of the safest modes for the production of true-to-type plants. © 2011 Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.
-
Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution
Physiology and Molecular Biology of Plants, 2010Co-Authors: Sunil Kumar, Manoj K. Rai, Narender Singh, Manisha MangalAbstract:Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l(-1) IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.
Veena Agrawal - One of the best experts on this subject based on the ideXlab platform.
-
srap and ssr marker assisted genetic diversity population structure analysis and sex identification in jojoba Simmondsia chinensis
Industrial Crops and Products, 2019Co-Authors: Jatin Kumar, Kuldeep Sharma, Monika Heikrujam, Veena AgrawalAbstract:Abstract Simmondsia chinensis (Link) Schneider, commonly known as Jojoba is a woody, dioecious shrub, cultivated all over the globe mainly for its commercially important seed oil (liquid wax ester). Investigations were carried out to analyze genetic diversity and population structure of 57 Jojoba genotypes belonging to 3 different eco-geographical regions of India (Gujarat, Jodhpur, and Jaipur) employing sequence-related amplified polymorphism (SRAP) and simple sequence repeat (SSR) markers. SRAP markers produced higher mean values of polymorphic bands (6.22), polymorphism information content (PIC: 0.47), effective multiplex ration (EMR: 5.36) and marker index (MI: 2.59) compared to SSR markers (5.87, 0.38, 5.26 and 2.23 respectively). Higher % polymorphism (86.30%) and resolving power (RP: 8.76) were detected by SSR markers than SRAP markers (82.30% and 8.71 respectively). Total genetic diversity (Ht) and genetic diversity within populations (Hs) in Jojoba genotypes were found to be very high (0.47 and 0.45 respectively). AMOVA analysis also revealed higher genetic variation within populations (77%) than among populations (23%). Very low genetic differentiation (Gst: 0.04) and high gene flow (Nm: 10.57) among different populations were observed. The Jojoba population of Gujarat region was observed to be highly diverse (h: 0.48), and that of Jaipur was least polymorphic (h: 0.40). Jojoba male genotypes were found to be more polymorphic (h: 0.46) compared to females (h: 0.44). UPGMA, Neighbor-Joining tree, and population structure analysis divided Jojoba populations into two main clusters, first comprising of Gujarat and Jodhpur populations and second including Jaipur population. Genetic diversity in different Jojoba populations was found to be strongly negatively and significantly correlated with the longitude factor. For sex identification in Jojoba, one SRAP primer combination, 'Em14/Me10' amplified a DNA fragment of 396 bp specific to male genotypes of Jaipur population. This male-specific marker was further positively validated on different genotypes growing in Jodhpur and Gujarat regions and sequenced.
-
ISSR marker-assisted selection of male and female plants in a promising dioecious crop: jojoba (Simmondsia chinensis)
Plant Biotechnology Reports, 2008Co-Authors: Kuldeep Sharma, Veena Agrawal, Sarika Gupta, Ravindra Kumar, Manoj PrasadAbstract:Simmondsia chinensis (Link) Schneider, a multipurpose and monogeneric dioecious shrub from arid zones, has emerged as a cash crop all over the globe. Its seed propagation poses severe problems due to its male-biased population: the male:female ratio is 5:1. Investigations have been carried out to generate a sex-specific Inter-simple sequence repeat (ISSR) marker for the early detection of male and female plants. Of the 42 primers analysed with a bulk sample of pooled male DNA and a bulk sample of pooled female DNA, only one primer, UBC-807, produced a unique ~1,200 base-pair fragment in the male DNA. To validate this observation, this primer was re-tested with individual male and female samples from eight cultivars. A similar unique ~1,200 bp fragment was present in the male individuals of all eight cultivars and completely absent in the female individuals tested. This is the first report of the use of ISSR markers to ascertain sex in physiologically mature S. chinensis plants.
-
Identification of sex in Simmondsia chinensis (Jojoba) using RAPD markers
Plant Biotechnology Reports, 2007Co-Authors: Veena Agrawal, Kuldeep Sharma, Sarika Gupta, Ravindra Kumar, Manoj PrasadAbstract:Simmondsia chinensis (Link) Schneider, a multipurpose dioecious shrub of arid zones, has emerged as a cash crop. It is being cultivated for its seeds which store liquid wax whose properties are similar to spermaceti (Sperm whale oil), a substitute for petro products and precious high-priced lubricants. Jojoba is a slow-growing desert shrub having a male biased (5:1; male:female ratio) population. Since there is no method available to determine the sex at the seedling stage, current investigations have been carried out to generate a sex-specific random amplified polymorphic DNA (RAPD) marker in jojoba which is based on the PCR amplification of random locations in the genome of plant. Of the 72 primers tested, only one random decamer primer, OPG-5, produced a unique ∼1,400 base pairs fragment in male DNA. To validate this observation, this primer was re-tested with the individuals of male and female samples of four cultivars. The unique ∼1,400 bp fragment was present in male individuals of all the four cultivars and completely absent in respective female individuals tested. To the best of our knowledge, this is the first report to ascertain the sex of jojoba plants at an early stage of development of the taxon.
-
effective protocol for in vitro shoot production through nodal explants of Simmondsia chinensis
Biologia Plantarum, 2002Co-Authors: Veena Agrawal, Surya Prakash, Shrish C GuptaAbstract:Nodal explants excised from 18 to 20-year-old female plants of Simmondsia chinensis if cultured on Murashige and Skoog's medium supplemented with 20 μM N6-benzyladenine (BA) differentiated an average of 2.7 ± 0.4 shoots in 11.5% explants. The percentage of nodal explants inducing multiple shoots enhanced significantly if in vitro raised shoots were used as source of explants. Nearly 100% cultures differentiated an average of 4.7 ± 2.0 shoots per explant on the same medium. Nearly 85% of the shoots induced roots when a pulse treatment of 50 μM indole-3-butyric acid (IBA) was given prior to their transfer to semi-solid MS medium containing 10 μM IBA + 0.5% activated charcoal + 1 μM BA. Plantlets were gradually hardened in Soilrite and acclimatized to soil.
-
somatic embryogenesis in jojoba Simmondsia chinensis
2000Co-Authors: Veena Agrawal, Surya Prakash, Shrish C GuptaAbstract:Simmondsia chinensis (Link) Schneider, commonly known as “jojoba” or “hohoba”. is a dioecious, evergreen perennial plant belonging to the monotypic family Simmondsiaceae. It is a native of Sonoran desert of the south western United States of America, north western Mexico and Baja California (Gentry, 1958; Benzioni, 1995). This species is distributed over about 256,000 square km area from 25 to 31° North latitude and from 109 to 117° West longitude (Gentry, 1958).
Jitender Singh Laura - One of the best experts on this subject based on the ideXlab platform.
-
EFFICIENT In vitro DIRECT REGENERATION FROM NODAL EXPLANTS OF Simmondsia chinensis (Link) SCHNEIDER-A POTENTIAL MULTIPURPOSE PLANT
2018Co-Authors: Raman Bala, Jitender Singh Laura, Vijay Singh BeniwalAbstract:Simmondsia chinensis (Link) Schneider (jojoba) is a potential multipurpose plant of arid and semiarid regions of India. An efficient method for in vitro direct plant regeneration from nodal segments of mature male and female S. chinensis has been developed. The nodal explants were cultured on Murashige and Skoog (MS) medium supplemented with various concentrations of 6-benzylaminopurine (BAP) and kinetin (Kin). The higher percentage (78.4±2.45) of shoot bud induction was observed at 2.5 mg/l BAP in male explants, while, percentage (86.2±2.14) of shoot bud induction obtained at 2.0 mg/l BAP in female explants. The influence of adenine sulphate (AdS) at 40 mg/l concentration with BAP was found best for vigorous shoot proliferation. For shoot multiplication in vitro derived shoots cultured on MS medium containing 2.0 mg/l BAP+1.0 mg/l NAA+40 mg/l AdS were produced the highest number (10.79± 2.81) of shoots with maximum (3.75±1.34 cm) shoot length in male cultures, while, the best combination of 2.0 mg/l BAP+0.5 mg/l NAA+40 mg/l AdS were yielded the highest number (9.64±1.23) of shoots with maximum (4.10±1.23 cm) shoot length in female cultures. Half strength of MS medium containing 3.0 mg/l IBA with 300 mg/l activated charcoal (AC) was found best for in vitro root induction in both male (98.7±1.64%) and female (97.3±1.04%) micropropagated shoots. The micropropagated plantlets were hardened under green house conditions and transplanted to field conditions with 92% survival rates. This standardized protocol of direct plant regeneration could be effective for large scale propagation of male and female S. chinensis and helps for successful commercialization of this plant.
-
an efficient and reproducible indirect shoot regeneration from female leaf explants of Simmondsia chinensis a liquid wax producing shrub
Physiology and Molecular Biology of Plants, 2015Co-Authors: Raman Bala, Vijay Singh Beniwal, Jitender Singh LauraAbstract:Simmondsia chinensis (Link) Schneider is a perennial, dioecious, drought resistant and multipurpose seed oil crop grown in arid and semi-arid conditions throughout the world. A reproducible and more efficient method for indirect shoot organogenesis from female leaf explants has been standardized. The leaf explants cultured on Murashige and Skoog (MS) medium with 1.0 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) alone produced the highest frequency of callus compared with 1.5 mg l−1 IBA. Maximum proliferation of callus was observed on MS medium containing a combination of 1.0 mg l−1 2,4-D with 0.5 mg l−1 BAP. For shoot differentiation, the proliferated callus was subcultured on MS medium supplemented with 6-benzylaminopurine (BAP) (1.0–4.0 mg l−1) along with 40 mg l−1 adenine sulphate as additive or in combination with α-naphthalene acetic acid (NAA) or Indole-3-butyric acid (IBA). Optimum shoots differentiated from callus was obtained on MS medium supplemented with 2.0 mg l−1 BAP and 0.2 mg l−1 NAA. On this medium, 100 % cultures were responded with an average number of 14.44 shoots per explant with their mean length of 4.78 cm. In vitro rooting (6.22 roots per explant) was achieved on half strength MS medium containing 2 % sucrose with 3.0 mg l−1 IBA and 300 mg l−1 activated charcoal (AC). Rooted plantlets were successfully hardened under control conditions and acclimatized under field conditions with 90 % success rate. The present protocol is highly efficient, reproducible and economically viable for large scale production of female plants.
Sunil Kumar - One of the best experts on this subject based on the ideXlab platform.
-
Callus induction and plant regeneration from leaf explants of jojoba [Simmondsia chinensis (Link) Schneider]
Indian Journal of Biotechnology, 2013Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:An efficient micropropagation protocol involving callus induction and shoot regeneration has been standardized in Simmondsia chinensis, an oil yielding, medicinal and multi- purpose plant species. Higher percent of callus proliferation (97.3%) was obtained from leaf explants, taken from field grown mature plant, when cultured on MS medium supplemented with 2,4-D (2.0 mg L-1)+BAP (0.5 mg L-1)+CH (100 mg L-1) within 20-22 d of inoculation. The callus was yellowish green in colour and soft in texture. Further, optimum shoot regeneration was obtained from the leaf derived callus on MS medium fortified with BAP (2.0 mg L-1)+NAA (0.5 mg L-1)+GA3 (0.3 mg L-1). About 92% cultures responded with an average number of 9.1 shoots per culture. The shoots obtained via callogenesis were rooted on half-strength agar-solidified MS medium supplemented with IBA (1.0 or 2.5 mg L-1). The medium containing 2.5 mg L-1 IBA was the best for rooting of shoots. The rooted shoots were transplanted to soil with 75% success. The protocol will be of immense importance in rapid mass multiplication of elite germplasm, as well as for conservation of this important species. Keywords:
-
Biotechnological advances in jojoba [Simmondsia chinensis (Link) Schneider]: Recent developments and prospects for further research
Plant Biotechnology Reports, 2012Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:Jojoba (Simmondsia chinensis), is a medicinal and oil-yielding, multi-purpose species of the family Simmondsiaceae. The most valuable product of jojoba seed is the liquid wax or jojoba oil which is used extensively in the cosmetic and bio-fuel industry. Propagation of jojoba is possible using conventional methods, but it is time consuming and cumbersome owing to long rotation periods, male-biased population, and long flowering and seed set time. The development of an efficient regeneration system is a prerequisite for a number of biotechnological interventions for the improvement of jojoba, such as genetic transformation, production of useful metabolites in vitro, etc. During the past decade, therefore, several attempts have been made for in vitro propagation of jojoba. Organogenesis has been achieved in this species from mature as well as juvenile explants. Present communication reports an overview of the in vitro regeneration of jojoba via organogenesis and somatic embryogenesis. Factors affecting organogenesis as well as production of synthetic seeds using shoot tips and axillary buds have also been discussed; however, efforts need to be made to develop an efficient genetic transformation system in jojoba. The purpose of this review is to focus upon the current information on in vitro propagation and biotechnological advances made in jojoba.
-
assessment of genetic fidelity of micropropagated plants of Simmondsia chinensis link schneider using rapd and issr markers
Acta Physiologiae Plantarum, 2011Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:RAPD (random amplified polymorphic DNA) and ISSR (inter simple sequence repeat) markers were screened to test the genetic integrity of jojoba (Simmondsia chinensis) plants multiplied through axillary bud multiplication from nodal segments. The in vitro raised plantlets were maintained for up to 12 in vitro subcultures. During the study a total of 48 (32 RAPD and 16 ISSR) primers were screened, out of which 24 RAPD and 13 ISSR primers produced a total of 191 (126 RAPD and 65 ISSR) clear, distinct and reproducible amplicons. The amplified products were monomorphic across all the selected micropropagated plants and were similar to the mother plant. The micropropagation protocol developed by our group for rapid in vitro multiplication is appropriate for clonal propagation of jojoba. The outcome supports the fact that axillary bud multiplication can also be used as one of the safest modes for the production of true-to-type plants.
-
Assessment of genetic fidelity of micropropagated plants of Simmondsia chinensis (Link) Schneider using RAPD and ISSR markers
Acta Physiologiae Plantarum, 2011Co-Authors: Sunil Kumar, Manisha Mangal, A. K. Dhawan, Narender SinghAbstract:RAPD (random amplified polymorphic DNA) and ISSR (inter simple sequence repeat) markers were screened to test the genetic integrity of jojoba (Simmondsia chinensis) plants multiplied through axillary bud multiplication from nodal segments. The in vitro raised plantlets were maintained for up to 12 in vitro subcultures. During the study a total of 48 (32 RAPD and 16 ISSR) primers were screened, out of which 24 RAPD and 13 ISSR primers produced a total of 191 (126 RAPD and 65 ISSR) clear, distinct and reproducible amplicons. The amplified products were monomorphic across all the selected micropropagated plants and were similar to the mother plant. The micropropagation protocol developed by our group for rapid in vitro multiplication is appropriate for clonal propagation of jojoba. The outcome supports the fact that axillary bud multiplication can also be used as one of the safest modes for the production of true-to-type plants. © 2011 Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.
-
Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution
Physiology and Molecular Biology of Plants, 2010Co-Authors: Sunil Kumar, Manoj K. Rai, Narender Singh, Manisha MangalAbstract:Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l(-1) IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.
