Govind Ram

Morphogenetic variation for artemisinin and volatile oil in Artemisia annua

Seeds of Artemisia annua cv. Jeevanraksha were sown in the nursery in the middle of December in 1997, 1998 and 1999. About 1-month old seedlings were transplanted in the field having sandy loam soil in the subtropical agroclimate of Lucknow, India. The plant tops were sampled fortnightly for leaves during vegetative phase and for leaves and capitula during post-flowering stages for the estimation of artemisinin content. The A. annua plants continued to grow logarithmically in height from the end of rosette phase at about 9 weeks to the pre-flowering stage at about 44 weeks age and attained a height of 3.4 m. The artemisinin content of the leaves was observed to be high from 0.8 to 1.0% in May and 0.8 to 1.3% through late July to late September. Subsequently, plants entered the reproductive phase. While in the vegetative phase, 90% of artemisinin was in the leaves, in the mature plants, about 30% of the artemisinin was in the leaves and 40% was in capitula. In the vegetative stage plants the younger leaves born on the tops of secondary and higher order branches were richer in the artemisinin than the older leaves. The tops of A. annua plants in their vegetative growth phase possessed low levels of essential oil at about 0.2% as compared to 1.2% of essential oil in the full blooming stage plants. The extraction of artemisinin from leaves is more economic than from the mixture of leaves and capitula on account of higher levels of lipids in the extract of the latter. Since A. annua plants grew logarithmically all through vegetative phase from March to late September and artemisinin content in the leaves was high in May and from late July to late September, it is suggested that under the subtropical agroclimates, A. annua crops may be harvested more than once. The ratooning is expected to reduce losses in artemisinin yield resulting from senescence caused dropping of old leaves and favour preponderance of young leaves found richer in artemisinin content.

Composition of essential oil from an annual crop of Hyssopus officinalis grown in indian plains

The plants of Hyssopus officinalis ssp. officinalis genotype raised through seeds sown in early December 1997 flowered in May 1998. The essential oil yields obtained upon hydrodistillation of above ground parts, harvested in May, were 0.25% on fresh herbage weight basis and 1.18% on dry herbage weight basis. The GC and GC–MS analysis of the essential oil led to the identification of 21 compounds representing 95.6% of the oil, having seven monoterpene hydrocarbons (32.3%), five oxygenated monoterpenes (60.5%) one phenol (0.2%) and six sesquiterpene hydrocarbons (0.35%). The major constituents of the camphorous odoured oil were pinocamphone (49.1%) >β-pinene (18.4%) >isopinocamphone (9.7%). Copyright

Screening of genotypes of menthol mint Mentha arvensis for high yields of herbage and essential oil under late cropping conditions of the sub-tropical Indo-Gangetic plains

SummaryThe essential oil yields and expression of related characters were compared for seven cultivar genotypes of menthol mint Mentha arvensis using two methods of planting in the winter rabi – summer season (October to July) in a sub-tropical agroclimatic environment. The crops of all the cultivars were planted in the field by (1) sowing of suckers on 2 January and (2) transplanting germinated pieces of sucker at different times between 17 March to 14 April. Staggering of transplanting time up to 7 April did not affect oil yields and the related plant growth properties of mint crops. The oil yields of the crops planted on 14 April were lower by about 30%. In the early sucker planted crops, the oil yields were about 30% higher than those obtained from the transplanted crops of 17 March to 7 April and about double that obtained from crops transplanted on 14 April. The oil yields from the crops of the superior genotype Kosi were equal to or higher than the corresponding means of all genotypes under both pl...

Temperature Relations for Seed Germination Potential and Seedling Vigor in Palmarosa (Cymbopogon martinii)

Because of non-synchronous flowering, fruiting, and dispersal of seeds, production and supply of quality seeds with well-defined germination potential parameters in Palmarosa are important issues for the growers. The objective of this study was to determine seed germination potential and seedling vigor of Palmarosa varieties under four temperature regimes at daily 16 h light/8 h dark regimes. At 25°C, germination percentage was highest for variety PRC-1 (67.8%), followed by varieties Tripta (59.3%), Trishna (57.5%), and Vaishnavi (35.5%). The mean for seedling vigor index I was highest for Trishna (277.7), followed by Tripta (259.3), PRC-1 (256.2), and Vaishnavi (140.4). However, vigor index II mean was highest for Tripta (0.2826), followed by PRC-1 (0.2615), Trishna (0.2600), and Vaishnavi (0.1388). Regardless of variety ranking by vigor index I vs. index II, the highest seedling vigor for all varieties was at 25°C using either index. However, since mass is a better indicator of seedling growth/health than length, vigor index II (based on mass) would give a better indication of early seedling vigor than index I (based on length). The low germination percentage and vigor of Vaishnavi is attributable to the genetic constitution of this self-pollinating variety. Significant decreases in germination percentage and vigor index I and II were observed at 20°C, 30°C, and 35°C. Days 2–3 and days 5–6 after sowing were the ideal times for making the first and final germination count, respectively. The study suggested that the Palmarosa nursery should have soil temperatures around 25°C with a day length of 16 h.

Genotype-independent germination-testing procedure for Isabgol.

Isabgol (Plantago ovata Forsk.) is an important medicinal crop cultivated on approximately 150,000 ha in India. The objectives of the present study were to establish genotype-independent germination-testing conditions, viz., in situ (Petri dish) and ex situ (two sub-conditions, i.e., vermicompost and vermiculite) and to determine the days of first and final count for in situ seed germination and final count for ex situ conditions using two Isabgol varieties, viz., ‘Niharika’ and ‘Mayuri’. Data were recorded on percent germination, germination energy, and germination period. Under in situ conditions, day 3 was appropriate for the first count and day 5 for the final count, whereas day 12 was suitable for the final count under ex situ conditions. The mean percent germination (82.50% in Petri dish, 43.00% in vermicompost and 44.46% in vermiculite) and germination energy (20.63% in Petri dish, 10.75% in vermicompost and 11.12% in vermiculite) were recorded at final count day for in situ and ex situ conditions. The germination period was found to be 5 d for in situ and 12 d for ex situ (i.e., vermicompost and vermiculite in earthen pots) test conditions. For percent germination, test conditions, varieties and days differed significantly. Variety ‘Niharika’ had the maximum percent germination (93.67% in Petri dish, 46.00% in vermicompost and 56.00% in vermiculite), followed by ‘Mayuri’ (71.33%, 40.00% and 33.33%, respectively). Differential behavior of the two varieties, viz., ‘Niharika’ and ‘Mayuri’, under in situ and ex situ conditions in the absence of any interacting effects indicated the germination capacity of the varieties was attributable to their genetic make-up, but first and final count day was genotype-independent.

Varietal Difference for Salt Tolerance During Seed Germination in Palmarosa (Cymbopogon martinii)

Abstract Palmarosa (Cymbopogon martinii var. Motia) is a major essential oil bearing perennial crop. Due to presence of geraniol and geranyl acetate, it is used worldwide in the cosmetic and perfumery industries. The objective of this study was to determine the salt tolerance relative to seed germination potential and seedling vigor index of three palmarosa varieties PRC-1, Trishna and Tripta under four levels of NaCl concentrations i.e. 0 mM, 50 mM, 100 mM and 150 mM NaCl at 25°C temperature coupled with 16 hrs light and 8 hrs dark photoperiod. The highest percentage of germination and seedling vigor index I and II was observed in control followed by 50 mM, 100 mM and 150 mM. Germination percentage decreased as NaCl concentration increased. Variety Trishna showed highest salt tolerance potential followed by PRC-1 and Tripta. Variety PRC-1 and Tripta have salt tolerance potential up to 50 mM NaCl concentration but Trishna have up to 150 mM NaCl concentration. The findings of this study be helpful in the study of germination behavior and selection of varieties and new suitable areas for commercial cultivation of palmarosa especially under saline conditions. The result of our study suggests that in the nursery more than 50 mM salinity soils should be avoided and variety Trishna can be grown up to 100 mM NaCl concentration at 25°C.

Impact of Salt Stress on Different Varieties of Palmarosa During Seed Germination

Abstract Palmarosa (Cymbopogon martinii (Roxb.) Wats.) is an essential oil bearing perennial crop having geraniol and geranyl acetate in its oil, widely used in cosmetic and perfumery industries. An experiment was conducted to determine germination percentage and seedling vigor index in PRC-1, Trishna and Tripta varieties of Palmarosa at KCl salt concentrations of 0 mM, 50 mM, 100 mM and 150 mM in Petri-dishes coupled with 16 hrs light and 8 hrs dark photoperiod placed at 25°C temperature. The highest percentage of germination and seedling vigor index I and II was observed in control followed by 50 mM, 100 mM and 150 mM. Germination percentage, seedling vigor index I and II decreased as KCl concentration increased. Highest KCl salt tolerance potential was showed by variety Trishna followed by PRC-1 and Tripta. Varieties PRC-1 and Tripta have salt tolerance potential up to 50 mM while Trishna have up to 150 mM KCl concentration. The result of our study suggests that farmers can raise Palmarosa nursery in normal soil condition and transplant it in soil salinity upto 50 mM KCl concentration. Hence, we suggest that in the nursery more than 50 mM salinity soils should be avoided except variety Trishna which can be grown up to 100 mM KCl concentration at 25°C.