Postharvest handling of ethylene with oxidative and absorptive means.

Fruit ripening is an unfolding of a series of genetically-programmed modifications and tend to be highly orchestrated irrevocable phenomenon mediated by ethylene. Phytohormone ethylene also leads to over-ripening, senescence, loss of texture, microbial attack, reduced post-harvest life and other associated problems during storage and transportation of fruits. Its harmful impacts on fresh fruits, vegetables, and ornamentals result in substantial product losses even up to 80%. Curbing of this inevitable menace is therefore need of the hour. Accrual of ethylene in packaging system should fundamentally be ducked to extend the shelf-life and uphold an adequate superiority of perishables in visual and organoleptic terms. The current review discusses about properties, factors affecting and impact of ethylene, intimidation of its impact at gene vis-à-vis activity level using gene-modification/inhibition techniques, chemical/physical in conjunction with other suitable approaches. It also entails the most commercially cultivated approaches worldwide viz. KMnO4-based oxidation together with adsorption-based scrubbing of ethylene in thorough details. Future ethylene removal strategies should focus on systematic evaluation of KMnO4-based scavenging, exploring the mechanism of adsorption, adsorbent(s) behavior in the presence of other gases and their partial pressures, volatiles, temperature, relative humidity, development of hydrophobic adsorbents to turn-up under high RH, regeneration of adsorbent by desorption, improvement in photocatalytic oxidation etc. and further improvements thereof. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05777-1.

Morpho-physiological and biochemical responses of cotton (Gossypium hirsutum L.) genotypes upon sucking insect-pest infestations.

The effects of sucking insect-pests on the morpho-physiological and biochemical changes in the leaves of four cotton genotypes-Bio 100 BG-II and GCH-3 (highly tolerant); KDCHH-9810 BG-II and HS-6 (highly susceptible)-were examined. Compared to tolerant genotypes, susceptible genotypes showed a decrease in relative water content, specific leaf weight, leaf area, photosynthetic rate, and total chlorophyll content, with an increase in electrolyte leakage. Hydrogen peroxide and total soluble sugar content were higher in susceptible plants. In contrast, resistant plants had higher levels of total soluble protein, total phenolic content, gossypol content, tannin content, peroxidase activity, and polyphenol oxidase. The findings demonstrated that the Bio 100 BG-II and GCH-3 genotypes effectively offset the impact of sucking insect-pests by modifying the factors mentioned above. The KDCHH-9810 BG-II and HS-6 genotypes could not completely negate the effects of sucking insect-pests. Customized metabolites and total soluble protein are more efficient in protecting cotton plants from damage brought on by infestations of sucking insects and pests. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01253-w.

Organic Farming and Bio-Nanomaterial Conflux: A Way Forward for Sustainable Agriculture.

Increasing population pressure and decreasing cultivable land brought the agricultural sector at an alarming situation of food production particularly in the developing countries. To feed the burgeoning population, the agriculture sector needs to become more productive and diversified while facing the adversity of climate change and limitations of natural resources. During 1960-70, the improved irrigation facilities, the use of fertilizers and pesticides in the cultivation of high yielding varieties of cereals successfully led to the Green revolution in India. In the present scenario, the low irrigation and fertilizer use efficiencies, poor pesticide application and delivery are amongst the important issues in developing countries that need to be addressed for getting higher productivity. Also, fertilizer and pesticide usage also had severe associated environmental consequences like eutrophication, resistance and resurgence in pest, toxicity to non-target organisms, residues in food and feed, accumulation in the environment, etc. In such conditions, organic farming, a traditional practice coupled with the exploration of bio-nanoparticles to achieve a sustainable production system seems to be a better option. This review focuses on current research developments in the areas of bio-nano-enabled crop nutrition, protection, post-harvest management, and the possibility of bio-nanomaterials and organic farming confluence to revolutionize the agricultural sector by ensuring sustainable food security for coming generations.

Cu-chitosan nano-net improves keeping quality of tomato by modulating physio-biochemical responses.

Minimizing the post-harvest losses in fruits and vegetables is one of the challenging tasks in agriculture. To address this issue, we report nano-net of Cu-chitosan nanoparticles (Cu-chitosan NPs) which has the ability to extend the shelf-life of stored tomato. The application of Cu-chitosan NPs (0.01-0.04%) significantly curtailed microbial decay (< 5 versus > 50% in control), physiological loss in weight (14.36 versus 28.13% in control), respiration rate (0.01173 versus 0.01879 g CO2 kg-1 h-1) and maintained fruit firmness (34.0 versus 17.33 N in control) during storage. Further, these NPs significantly retarded loss of titratable acidity, retained total soluble solids, total and reducing sugars, lycopene, ascorbic acid and inhibited polyphenol oxidase. Likewise, NPs effectively preserved L* (lightness), a* (red/green) and b* (blue/yellow) values and maintained organoleptic score. Scanning electron microscopy study confirmed that Cu-chitosan NPs orchestrate into an invisible-intangible nano-net over tomato surface which may plausibly act as a potential barrier at all possible openings (stem scar, cuticle wax, lenticels, and aquaporins) to control microbial infection, moisture loss, gas exchanges and respiration rate. Overall, nano-net extended keeping quality of tomatoes up to 21 days at room temperature (27 ± 2 °C, 55 ± 2% relative humidity).

Genotype-Specific Antioxidant Responses and Assessment of Resistance Against Sclerotinia sclerotiorum Causing Sclerotinia Rot in Indian Mustard.

Productivity of Indian mustard, an important oilseed crop of India, is affected by several pathogens. Among them, the hemibiotroph Sclerotinia sclerotiorum, which causes sclerotinia rot disease, is the most devastating fungal pathogen causing up to 90% yield losses. The availability of host resistance is the only efficient approach to control and understand the host-pathogen interaction. Therefore, the present investigation was carried out using six Indian mustard genotypes with contrasting behavior towards sclerotinia rot to study the antioxidant resistance mechanism against S. sclerotiorum. The plants at post-flowering stage were inoculated with five-day-old pure culture of S. sclerotiorum using artificial stem inoculation method. Disease evaluation revealed significant genotypic differences for mean lesion length among the tested genotypes, where genotype DRMR 2035 was found highly resistant, while genotypes RH 1569 and RH 1633 were found highly susceptible. The resistant genotypes had more phenolics and higher activities of peroxidase, catalase and polyphenol oxidase which provide them more efficient and strong antioxidant systems as compared with susceptible genotypes. Studies of antioxidative mechanisms validate the results of disease responses.

Simultaneous Estimation of Twenty Eight Phenolic Compounds by a Novel and Expeditious Method Developed on Quaternary Ultra-Performance Liquid Chromatography System with a Photodiode Array Detector.

Plant secondary metabolites including phenolics and flavonoidsare synthesized through phenylpropanoid and phenylpropanoid-acetate pathways and significantly contribute against adverse effect of abiotic and biotic stresses. Herein, we present the development and execution of a novel and expeditious ultra-performance liquid chromatographic-photodiode array (UPLC-PDA) method for qualitative and quantitative analysis of 28 phenolic compounds comprising of flavonoids, phenolic acids, aldehydes and alcohols. The method is able to separate phenolic compounds in just 17 minutes with the separation of isobaric species such as 3,4 dihydroxybenzoic acid and 3,5 dihydroxy benzoic acid; quercetin and taxifolin. Linear curves concentrations ranged from 6-18 µg/mL (3,5 dihydroxy benzoic acid), 4-12 µg/mL (catechin and salicylic acid) and 2-6 µg/mL for rest of the compounds and correlation coefficients were >0.994. The limit of detection (LOD) varied from 0.04-0.45 µg/mL. Cotton root samples were used to assess the method in terms of recovery efficiency (85-120%), precision (0.12-4.09%) and intermediate precision (0.32-4.0%).Phenolics and flavonoidsin root samples of healthy and diseased plants as well as leaf samples of healthy plants were successfully quantified using this novel method without an expensive Mass Spectrometer.

Optimization, purification and characterization of pectinases from pectinolytic strain, Aspergillus foetidus MTCC 10559.

A strain (MPUAT-2), isolated from coconut hull and identified as Aspergillus foetidus MTCC 10559, was used for pectinase production. Optimum pectinase production was obtained at pH 8.0 and temperature 35 degrees C under static conditions in submerged fermentation after 5 days of incubation. Orange peel, a byproduct of fruit industry, was used as a sole carbon source (3% w/v) to produce high pectinase, thus making the process cost effective. The culture filtrate was analyzed for pectin methyl esterase (PME) and endopolygalacturonase (endo-PG) enzymes. The enzymes, PME and endo-PG were purified using ammonium sulphate precipitation and molecular exclusion chromatography (Sephadex G-75) with corresponding recovery of 39.3 and 44.3%. The partially purified enzymes were also characterized for their kinetic properties.