Post-harvest quality and quantification of betalains, phenolic compounds and antioxidant activity in fruits of three cultivars of prickly pear (Opuntia ficus-indica L. Mill)

Postharvest quality, quantification of betalains, phenolic compounds, and antioxidant activity of peel, pulp, and juice of fruits of three prickly pears (Opuntia ficus-indica L. Mill.) cultivars of Colegio de Postgraduados in México, were measured. The red and orange cultivars showed outstanding features of postharvest quality (size, texture, TSS and pulp and juice content) highest content of betalains and phenolic compounds. Therefore, highest antioxidant activity. In general, the highest content of bioactive compounds was detected in the peel, besides the content in pulp and juice did not show statistically significant differences. Phenolic content is very high in comparison with other fruits. Antioxidant activity was measured by three assays:FRAP, ABTS, and DPPH. Three cultivars showed a high correlation between antioxidant activity and phenolic compounds. The methodologies used in this work are a very useful tool for the quantification of bioactive compounds in O. ficus-indica fruit tissues.

In vitro multiplication protocol for Curcuma mangga : Studies on carbon, cytokinin source and explant size

Mango ginger (Curcuma mangga Valeton & Zijp.) is an underutilized rhizomatous species that has been valued in tropical Asian countries as a source of vegetable, spice, salad, medicine, and essential oil. This species is hardy and requires less care for obtaining good yields. Rhizomes are the commonly used propagules for the species, which are also the economic part of the crop. Huge quantity of seed rhizomes is required to promote this crop in larger areas. An efficient in vitro multiplication protocol is one of the options to meet the planting material requirement. Effects of carbon source (glucose, fructose and sucrose) and concentration (1 and 3%, w/v), cytokinins (BAP and meta topolin) and concentration (1 mg/L and 2 mg/L), size of explants (one/ two/ three bud) and IBA treatment (0, 250, 500 and 1,000 mg/L) for concurrent ex vitro rooting cum hardening were studied. Results revealed that for facilitating efficient multiplication, the medium should be supplemented with glucose (3%) as a carbon source and meta topolin (1 mg/L) as cytokinin. Two-bud explant should be used for subculture as it promoted superior shoot proliferation. Concurrent ex vitro rooting cum hardening was possible even without auxin treatment. The present protocol could be useful for large-scale production of quality planting material of this underexploited tropical species.

Induced variability for yield and its attributing traits in cluster bean [Cyamopsis tetragonoloba (L. ) Taub] through gamma irradiation

Gamma ray is an effective mutagen which creates useful variability for crop like cluster bean where the natural variation is very meagre and creation of variability by conventional methods is cumbersome. In the present study, cluster bean cv. Pusa Navbahar was treated with different level of gamma rays from 50 Gy to 600 Gy with 50Gy interval and obtained M2 population was subjected to variability estimation for yield and its attributing traits in augmented block design. The variance between the control and the mutants was found to be significant for plant height, number of pods per cluster, number of pods per plant, pod length, pod width, pulp to seed ratio. For these traits, PCV ranged from 14.28 per cent (pod width) to 31.99 per cent (pulp to seed ratio) whereas, GCV ranged from 10.10 per cent (pod width) to 24.16 per cent (pulp to seed ratio). The heritability in broad sense ranged from 50 per cent (pod width) to 79.99 per cent (Plant height). Genetic advance expressed as percentage over mean ranged from 2.06 per cent (pod width) to 222.44 per cent (plant height). The traits like plant height, pod length, pod width, pulp to seed ratio showed sufficient variability due to induced mutation. All these traits showed medium to high heritability and high genetic advance hence selection for these traits will be effective.

Responses of different okra (Abelmoschus esculentus) cultivars to water deficit conditions

A pot experiment was conducted to evaluate the adverse effects of drought on different okra cultivars and to identify the most suitable okra cultivar for growing in drought conditions. Five okra cultivars namely Pusa Green, Clemson, Sabz Pari, Pusa Swani and Mehak Pari were subjected to three drought levels i.e., control (100% Field capacity),50% and 25% Field Capacity (FC). Physiological parameters like fresh and dry weight of plant and plant height were recorded along with biochemical attributes such as chlorophyll content (a, b, total) carotenoids, total protein, proline content, and Membrane stability index (MSI%). Results showed that drought significantly reduced all the studied parameters and at maximum drought (25% FC) lowest values of fresh weight (12.42g), dry weight (1.22g), plant height (7.86cm), chlorophyll a (9.02mg/g FW), chlorophyll b (18.69mg/g FW), total chlorophyll (27.71mg/g FW), carotenoids (11.80mg/g FW), total protein (2.73mg/g FW),whereas maximum Proline (21.36μg/g FW), and MSI (72%) were observed under the same drought. The results concerning responses of okra cultivars under drought conditions showed that maximum. Fresh weight (15.25g) and Dry weight (2.74g) was observed in Pusa green while maximum Plant height (13.77cm), Chlorophyll a (14.38mg/g FW), Chlorophyll b (24.41mg/g FW), Total Chlorophyll (38.80mg/g FW), Carotenoids (18.57mg/g FW), Total Protein (5.44mg/g FW), Proline (27.78μg/g FW), and MSI (56.33%) were produced by Sabz Pari. Hence it can be concluded that drought causes significant variation on physical and biochemical attributes of okra whereas Sabz Pari showed resistance towards the applied stress and produced better results.

Isolation and characterization of microsatellite markers from Garcinia indica and cross species amplification

Garcinia indica popularly known as ‘Kokum’ or Murugalu”, is a medium-sized evergreen tree found in the western-ghats of India. This tree species is highly exploited to produce anti-obesity drugs and culinary purposes. Its population is threatened by overexploitation and loss of habitat. The development of microsatellite markers would help in understanding the genetic structure and further to develop appropriate conservation strategies. In this study, using next generation sequencing platform Illumina Hiseq 2000, we have sequenced the partial genome of G. indica and identified 3725 microsatellites. Forty-eight microsatellite markers were analyzed using 30 accessions. Polymorphism information content (PIC) values ranged from 0.718 to 0.968 with a mean value of 0.922. Allele per locus ranged from 3 to 33 per locus. The probability of identity values ranged from 0.00329 to 0.30489. Cross-species amplification SSR primers in the related species showed a moderate transferability from 12.5 % (for G. morella) to 18.7%(for G. gummigutta)

Genetic variability studies in amaranthus (Amaranthus spp.)

An investigation was carried out to estimate the nature and extent of genetic variability​ ​among twenty Amaranthus genotypes (Amaranthus spp.) under a randomized block designduring the year 2019-20. The phenotypic coefficient of variation was higher than the genotypic​ ​coefficient of variation for all the traits. High genotypic coefficient of variation (GCV) and​ ​phenotypic coefficient variation (PCV) was observed for leaf area, leaf area index, leaf area​ ​duration, AGR, dry weight of leaf per plant, specific leaf weight, speed of germination,​ ​chlorophyll content and ascorbic acid (vitamin C). Moderate GCV and PCV were observed​ ​for leaf length, leaf width, petiole length, dry weight of stem per plant, leaf: stem ratio and​ ​foliage yield per plant. The high estimates of heritability coupled with higher values of genetic​ ​advance as per cent mean (GAM) were observed for the parameters like test weight, speed of​ ​germination, germination percentage, seedling dry matter, seedling vigour index-1, seedling​ ​vigour index-2, plant height, leaf length, leaf width, leaf area, leaf area index, leaf area​ ​duration, AGR, specific leaf weight, stem weight per plot, dry weight of leaf, dry weight of​ ​stem, leaf: stem ratio, foliage yield per plant, chlorophyll, ascorbic acid and beta- carotene​ ​content which indicates the predominance of additive gene action. Arka Arunima,​ ​Chikmagalur local, IC-551486, IC-551494 and IC-551466 recorded high foliage yield per​ ​plot and these can be utilized in further breeding programmes.

Effect of fungicide and essential oils amended wax coating on quality and shelf life 77-90 of sweet orange (Citrus sinensis Osbeck)

Laboratory research was conducted to study the effect of wax amended coating on the shelf life of Citrus sinensis Osbeck during 2017-18 at Rampur, Chitwan. The experiment was conducted in single factor Completely Randomized Design (CRD) with nine treatments and four replications. The treatments consisted of carbendazim and three essential oils viz. lemongrass, mentha and eucalyptus oil at two different concentrations of 0.1% and 0.5%, all of them infused with 10% wax emulsion. The wax treatment devoid of fungicide and essential oils served as control. The application of essential oils with wax improved shelf life and enhanced juice retention, firmness, titratable acidity, vitamin C and disease reduction. But total soluble solid was found higher in fruits treated with wax emulsion only. The highest shelf life and disease control was obtained with wax with 0.5% carbendazim but waxing with 0.5% eucalyptus oil and 0.5% lemongrass oil can be better alternatives considering their superior performance in environmental aspects, consumer preferences and quality parameters like juice retention, firmness, titratable acidity and vitamin C.

Morpho-physiological parameters associated with chlorosis resistance to iron deficiency and their effect on yield and related attributes in potato (Solanum tuberosum L.)

The aim of the study was to assess genotypical differences over different stages for morphophysiological parameters associated with iron (Fe) deficiency and their effect on yield. The factorial pot experiment was comprised of two major factors, i) soil-Fe status of natural vertisol [Fe-sufficient and Fe-deficient soils], and ii) genotypes [CP-3443, CP- 4105, CP-3486 and CP-4069] with differential iron-induced deficiency chlorosis (IDC) response. Data were recorded and associations between different traits were estimated. Under Fe-deficient soil, tolerant genotype (CP-3443) recorded significantly higher chlorophyll content, peroxidase activity in leaves, and better yield compared to susceptible genotypes which verified usefulness as IDC tolerant potato genotypes characteristics.

Characterization and evaluation of mountain sweet thorn (Flacourtia montana J. Grah) collections

Mountain sweet thorn (Flacourtia montana J. Grah) is an indigenous underutilized fruit of the Western Ghats and other regions of peninsular India. It is a close relative of Governor’s plum. It is a bushy shrub or small tree with spiny trunks and branches which may grow up to 2.5 m in height. The fruits are bright dark red 1-2 cm in diameter, sweet edible, and have the potential for processing into jams and jellies. The presence of thorn is one of the major hurdles for the commercialization of this crop. Thus, seeds of the thorny plants of the Mountain sweet thorn were collected from different locations, and seedlings were planted to identify the suitable line. The plant height ranged from 425 cm (accession 0208) to 710 cm (accession​ ​0202). The plant girth ranged from 34.5 cm to 82 cm. The growth data revealed that all​ ​the accessions are vigorous, fast-growing, and have various levels of thorniness. All the​ ​accessions were found to be spreading type. Significant variability was recorded for leaf​ ​characteristics among the accessions studied. Three major clusters were observed in​ ​cluster analysis for morphological and fruiting characters consisting of 1, 8, and 9 accessions,​ ​respectively. The number of fruits ranged from 0 to 4008. The highest yield (9.46 kg/plant)​ ​was obtained in accession - 0106 followed by accession- 0201 (7.83 kg). The average​ ​fruit weight ranged from 1.51 g to 3.94 g. The highest fruit weight (3.94g) was also recorded​ ​in 0106 followed by 2.84 (0102). The total soluble solids ranged from 10 0 Brix to 15.1 0​ ​Brix. Overall, accession 0201 was found better than others with respect to yield, regular​ ​bearing, and less thorniness.

Effect of spectral manipulation and seasonal variations on cut foliage production and quality of Philodendron (Philodendron ‘Xanadu’)

Influence of spectral manipulation of light using coloured nets and seasonal variation on cut foliage yield and quality of Philodendron ‘Xanadu’ was evaluated under red, green, white and black coloured shade nets permitting light intensities ranging from 240.50 to 370μ mol m-2 s-1 (75% shade net), for two consecutive years from 2014-16, at ICARIIHR, Bengaluru. The plants grown under white shade net (75% shade) resulted in higher foliage production plant-1month-1 (14.53) and were on par with those grown under green shade net. The quality of the cut foliage in plants grown under white shade net with respect to stalk length (24.91 cm) and width of the lamina (5.19 cm) was on par with those under green and black shade nets. Coloured shade nets did not influence the vase life of the cut foliage. Developmental stages of the foliage under the different coloured nets have indicated that leaves attained the harvestable maturity stage at 29.92 days post-emergence under white shade. Cultivation of Philodendron ‘Xanadu’ under white shade resulted in maximum cut foliage yield and quality.