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Morpho-physiological responses of Chrysanthemum coronarium and Calendula officinalis to hyperaccumulation of cadmium
(Punjab Agricultural University, Ludhiana, 2020) Singla, Himani; Jhanji, Shalini
The present investigation entitled ―Morpho-Physiological responses of Chrysanthemum coronarium and Calendula officinalis to hyperaccumulation of cadmium‖ was conducted in the Department of Floriculture and Landscaping and Department of Botany, Punjab Agricultural University, Ludhiana during the year 2019-20. The seedlings of Chrysanthemum coronarium and Calendula officinalis were planted in pots filled with soil treated with different concentrations (0, 20, 40, 60, 80 and 100 ppm) of cadmium (Cd ) ,applied as Cd(NO3)2. Growth parameters viz. plant height, number of leaves, leaf area per plant, leaf dry weight, number of flowers, flower diameter, of both the ornamentals were affected with increase in Cd concentration but at 20 ppm there was no adverse effect on growth of Calendula. Cadmium retarded plant growth as dry weight of Chrysanthemum roots declined by 20%, stem by 31% and leaves by 14% under 100 ppm Cd application and the corresponding values for Calendula were 18, 28 and 14% respectively. With increase in Cd concentration, there was reduction in moisture content, relative water content and membrane integrity of leaves and petals of both plant species. Significant reduction in various biochemical parameters viz., total soluble sugars, total soluble proteins, chlorophyll and carotenoid content was also recorded with increase in Cd concentrations. There was increase in Cd content in roots, stem, leaves and flowers of both ornamentals, being higher in Calendula than Chrysanthemum. DTPA-extractable Cd in soil was decreased from equilibrium to budding to commercial harvest and decline being highest under 60 ppm, 45.75% in Calendula and 34% in Chrysanthemum showing greater Cd uptake by roots of Calendula and high mobility index (MI) from soil to root than Chrysanthemum whereas uptake was recorded to be more by stem of Chrysanthemum than Calendula due to its higher biomass. Both Calendula and Chrysanthemum showed Bio-concentration factor (BCF) and Translocation factor (TF) to be more than 1 whereas Enrichment factor (EF) and Remediation factor(RF) were more than 1 in both species but higher in Calendula than Chrysanthemum. Thus, besides commercial significance of Calendula and Chrysanthemum both ornamentals can be used for phytoremediation of Cd contaminated soils.
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Effect of fruit harvest stage and storage on quality and longevity of cucumber (Cucumis sativus L.) seeds
(Punjab Agricultural University, Ludhiana, 2020) Pathania, Kartik; Navjyot Kaur
The present investigation entitled “Effect of fruit harvest stage and storage on quality and longevity of cucumber (Cucumis sativus L.) seeds” was conducted during 2019 and 2020. The experiment was conducted in completely randomized design with two factors namely stages of fruit harvest and stages of in-situ storage duration of fruits. The fruits were harvested at 30, 40 and 50 days after anthesis (DAA) and seeds were extracted immediately and after 5, 10 and 15 days of fruit detachment from plants. Percentage of developed seeds, seed weight per fruit (g), 100 seed weight (g), membrane stability index, germination (%), seedling vigour index, speed of germination and storage reserves in seeds viz., starch, total soluble proteins and total amino acids were increased significantly with delay in stage of fruit harvest from 30 to 50 DAA and increased in-situ storage duration of fruits from 0 to 15 days. However, the number of undeveloped seeds, relative water content, mean germination time, total soluble sugars and oil content in seeds decreased with delay in stage of fruit harvest and increased insitu storage duration of fruits from 0 to 15 days during both the years. Total soluble sugars and free amino acids in fruit pulp increased while total soluble proteins and starch content in fruit pulp decreased with delay in stage of fruit harvest and increased in-situ storage duration of fruits during both the years. Seeds extracted from different treatments were stored for 8 months and tested for different parameters at bi-monthly intervals. After 8 months of seed storage, best seed quality parameters were obtained when seeds were extracted from fruits harvested at 50 DAA with in-situ storage of 10 days. Based on two years data, it can be concluded that to obtain maximum seed yield, quality and storability of cucumber seeds, fruits must be harvested at 50 DAA with at least in-situ storage of 10 days.
Open Access
Effect of different green shade net houses on growth and biochemical components of various Ocimum spp.
(Punjab Agricultural University, Ludhiana, 2020) Aayushi; Sharma, Rajni
The effect of different green shade net houses on the growth and biochemical constituents were recorded during the present investigation on four different Ocimum spp. (O. tenuiflorum, O. sanctum, O. basilicum and O. gratissimum). The plants were grown under five different shading intensities viz- 35%, 50%, 75%, 90% and open (no net condition) as control. Growth parameters like number of branches, number of leaves, total fresh weight, total dry weight, leaf dry weight, shoot dry weight were recorded to be higher in 35% shading intensity than control and other shading intensities whereas stem diameter and root length were higher in control in comparison to other shading intensities. However, parameters like plant height, internodal length and leaf area were recorded higher in 90% shading intensity than in control. All growth parameters except plant height, internodal length and leaf area were found to be suppressed as the shading intensity was increased beyond 50%. The requirement of moderate light intensity for better growth and development has been reflected in maximum growth parameters. Variable response was observed for biochemical parameters in different shading intensities. However, the trend was same for all species. Biochemical parameters like total carotenoid content, total sugars, reducing and soluble protein were recorded maximum in control i.e. under full sunlight followed closely by 35% shading intensity while 90% shading intensity recorded highest chlorophyll a, chlorophyll b and total chlorophyll content. Total phenols and flavonoids were recorded to be highest in control (no net conditions) followed closely by 35% shading intensity while alkaloids and terpenoids were recorded to be highest in 35% shading intensity followed closely by control. However, biochemical parameters were influenced but phytochemical compounds like alkaloids and terpenoids recorded increase under 35% shading intensity which contribute to its medicinal properties. Therefore, in present investigation, Ocimum spp. performs better in 35% shading intensity than other shading intensities and control.
Open Access
Effect of glycine betaine and proline on seed germination and seedling growth of oat (Avena sativa L.) under salt stress
(Punjab Agricultural University, Ludhiana, 2020) Makkar, Astha; Gupta, Namrata
In present investigation, seeds of oats (Avena sativa L.) were subjected to different concentrations of salt stress (25mM, 50mM, 75mM 100mM) in OL-1896 and OL-1962 genotypes to study the effects of salinity on physiological (seed germination, seedling length, biomass, seed vigour and speed of germination) and biochemical parameters (total soluble sugars, proteins, MDA and activities of different antioxidant enzymes viz SOD, POX and CAT). Physiological parameters decreased with increasing salinity level whereas out of biochemical parameters; total soluble sugars, SOD, POX and MDA activity increased and total soluble proteins and CAT decreased. From the above stress levels used, two stress levels i.e. 50mM and 75mM were selected and seeds were treated with different concentrations of proline (5mM and 10mM) and glycine betaine (10mM and 20mM) to study their influence on physiological as well as biological parameters under salt stress conditions. The results showed that the seeds treatments (PRO 5mM, 10mM and GB 10mM, 20mM) improved the activity of physiological and biochemical parameters and reduced the harmful effects of salt stress in both genotypes of oats. Genotype OL-1896 was comparatively more tolerant to salt stress. Also, proline 10mM and glycine betaine 20mM was found to be more effective than proline 5mM and glycine betaine 10mM. Thus, the results suggest that exogenous application of proline and glycine betaine increased salt tolerance in oat seedlings.
Open Access
Effect of priming on enhancing storability of brinjal (Solanum melongena L.) seeds
(Punjab Agricultural University, Ludhiana, 2020) Japneet Kaur; Bedi, Seema
The present study was conducted on brinjal (Solanum melongena L.) seeds var. Punjab nagina. The quality of brinjal seeds in-terms of vigour and viability severely declines as a result of natural ageing during storage between harvesting and next sowing season. The objective of this study was to evaluate the effect of various priming treatments on the quality and storability of brinjal seeds. The freshly harvested seed was divided into two lots. One of these seed lots was subjected to accelerated ageing to obtain low vigour seed and the other lot was considered to be high vigour. The high and low vigour seeds were primed with KNO3 (1%), GA3 (100ppm), KH2PO4 (0.1M), PEG 6000 (30%) and H2O for 12 hours at 25oC. Thereafter, the seeds were stored in moisture impervious bags for 12 months in a refrigerator (4C). The objective was to observe whether the priming treatments improve the seed vigour and also retain the advantages obtained from priming during storage. The seeds were drawn at three-monthly intervals, viz. zero, three, six, nine and twelve months of storage. Physiological (germination percentage, speed of germination, mean days to germination, seedling length, root length, shoot length, seedling dry weight and seedling vigour index) and biochemical (Total soluble sugars, total soluble proteins, α-amylase activity and membrane stability index, starch content, total free aminoacids) observations were recorded. With an increase in storage duration, a decline in physiological and biochemical aspects of seed quality was observed in both high and low vigour seeds. All the priming treatments improved the germination related parameters in both high and low vigour seeds over control but the extent of improvement varied. Seed priming with GA3 (100ppm) followed by priming with KNO3 (1%) were found to be the best treatments for both high and low vigour seeds even after storage for 12 months.
Open Access
Effect of shading on the performance of Indian mustard (Brassica juncea L. Czern and Coss) genotypes
(Punjab Agricultural University, Ludhiana, 2020) Sonika; Sharma, Pushp
The present investigation was carried out to assess the effect of shading on the performance of Brassica juncea genotypes. Shading was done with nets for one month commencing from mid December 2018 – mid January 2019 which cuts 25-30% of natural sunlight. Flower and fruit initiation took more number of days while flowering and fruiting duration were reduced with shading. Differential behaviour with shading was reported for reproductive phase and days to maturity. PHR-126 took maximum days for flowering and siliqua initiation, PBR-396 for flowering completion and duration, PBR-561 for siliquing completion and duration. Reproductive phase was shortened by 2.3 days whereas days to maturity were comparable under control and shaded treatments. Chl a (23.8%), carotenoids (19.1%) and SPAD (8.5%) were significantly reduced after 10 days of shading and 31.5%, 27.9% and 6.7% after 30 days of imposed low light stress. However, chlorophyll b exhibited an increase of 16.7% and 37.5%. The photochemical efficiency of PSII was reduced by 2.8% under shade. Leaf traits like, leaf area, SLA, SLW, LWR and RWC declined under shade while RSD and WSD increased at both the studied stages. Leaf and stem anatomy was affected by low light stress as the thickness of tissues was reduced in comparison to control in all the studied genotypes. Kranti, PBR-450, PBR-396 and PBR-464 were registered for higher anatomical characteristics with minimum decline under low light stress as compared to control. Stomatal responsiveness to low light revealed smaller size of stomata with lower stomatal frequency and index on both the abaxial and adaxial leaf surface as compared to control. Antioxidative enzymes and MDA content increased whereas sugars and protein content decreased with shading assayed at two stages. Low light stress had a profound effect on growth parameters, yield components and seed yield in studied genotypes with a minimum reduction of 1.1% for plant height and 1.8% for primary branches in Varuna, 0.5% for length of main raceme in PBR-396 whereas 2.1% for secondary branches in PBR-561. PBR-396 suffered lesser reduction in seed yield followed by Kranti accompanied by lesser decline in the morphophysiological traits and increased antioxidative enzymes. Seed yield had positive association with phenological traits except flowering duration under low light stress. Stomatal length and size were significantly associated with seed yield under both stressed and non-stressed condition. Kranti, PBR-396 and PBR-464 were promising cultivars under low light stress with seed yield reduction of ≤ 20%, SSI (≤1.0), STI (≥0.5) and YSI (≥0.70).
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Effect of coloured nets on growth and biochemical components in different species of Ocimum
(Punjab Agricultural University, Ludhiana, 2020) Vij, Lavanya; Sharma, Rajni
The effect of different colored nets on the growth and biochemical constituents were recorded during the present investigation on four different Ocimum spp. (O. tenuiflorum, O. sanctum, O. basilicum and O. gratissimum). The plants were grown under five different coloured nets viz- green, blue, black, red, white all cutting the light intensity by 50% and open (no net condition) as control. Growth parameters like number of branches, number of leaves, total fresh biomass, total dry biomass, root dry biomass, shoot dry biomass were recorded to be higher in control than coloured nets. However, shoot length, root length and leaf area were recorded higher in white coloured net than in control. All growth parameters except shoot length and leaf area were found to be suppressed as they recorded lowest values in black coloured net. The requirement of high light intensity for better growth and development has been reflected in all our growth parameters. Thus, suggesting that growth parameter are recorded higher in control (no net condition) than under the coloured nets. Variable response was observed for biochemical parameters in different coloured nets. However, the trend was same for all species. Biochemical parameters like total carotenoid content, total anthocyanin content, total sugars, reducing and non reducing sugars and protein were also recorded maximum in control i.e. under full sunlight while black coloured net recorded highest chl a, chl b and total chlorophyll content among all treatments. Total phenols, flavanoids, saponins and essential oil content were recorded to be highest in red coloured net while alkaloids were recorded to be highest in white coloured net followed closely by red coloured net. Ocimum spp. is an important medicinal herb which is predominantly sun loving in nature. However, biochemical parameters were influenced and phytochemical compounds like phenols, flavanoids, alkaloids and saponins recorded increase under coloured nets in the biochemical constituents which contribute to its medicinal properties.
Open Access
Evaluation of morpho-physiological and biochemical changes in garlic (Allium sativum L.) bulbs stored under different temperature conditions
(Punjab Agricultural University, Ludhiana, 2020) Jashanpreet Kaur; Sharma, Rajni
The present investigation was carried out to assess the optimum storage temperature for garlic (Allium sativum L.) with minimum deterioration and also for the most promising genotype on the basis of morpho-physiological and biochemical parameters. Garlic genotypes (PG-17, PG- 18, PG-29, PG-46 and PG-48) were kept in three storage temperatures; 0°C, 15°C and room temperature for four months for evaluation of various parameters and then planted to evaluate their growth performance. Temperature and months of storage had a decreasing influence on garlic genotypes. PG-18 was found to be a promising genotype irrespective of temperature storage conditions due to its better performance than other genotypes in morphological properties prior to storage such as bulb diameter (4.5cm), neck diameter (2.7cm), bulbing ratio (0.6), bulb’s fresh weight (28.7g) and dry weight (17.5g), number of cloves per bulb (24.3). PG-18 also retained maximum biochemical composition till end of storage such as total phenols (10.5 mg/g DW), flavonoids (0.59 mg/g DW), ascorbic acid (5.70 mg/g DW), total soluble sugars (17.25 mg/g DW) and reducing sugars (12.71 mg/g DW). Also, genotype PG-18 had highest germination percentage (66.93%), maximum vigour index II (2580) and highest survival percentage (66.45%). Room temperature storage was found to be the optimum storage condition for garlic bulbs as garlic of room temperature performed better than other temperature stored garlic by the end of storage in case of compactness, bulb’s fresh weight (14.86g) and dry weight (8.86g), total phenols (10.46 mg/g DW), ascorbic acid (5.12 mg/g DW) and total soluble sugars (11.88 mg/g DW). Also, room temperature stored garlic, on subjecting to germination, had highest germination percentage (77.01%) and survival percentage (88.40%), maximum vigour index II (2717) and more plant fresh weight (51.40g) , dry weight (21.49g) and height (69.72 cm) than 15°C garlic.
Open Access
Morpho-anatomical and biochemical characterization of cotton in relation to whitefly tolerance
(Punjab Agricultural University, Ludhiana, 2020) Taruna; Gupta, Neha
The present investigation entitled “Morpho-anatomical and biochemical characterization of cotton in relation to whitefly tolerance” was undertaken to evaluate the performance of backcross progeny carrying genomic introgressions of wild cotton G. armourianum (D-genome) in G. hirsutum for whitefly tolerance. Various leaf morphoanatomical characteristics such as stomatal frequency, gossypol glands, trichome density, trichome length, trichome angle, mesophyll arrangement and leaf thickness were studied in parents G. armourianum Acc. PAU 1, G. hirsutum cv. F 1861 and LH 1556, their F1, BC1F1, BC2F1 derivatives to find out their relationship with B. tabaci infestation on host cotton. A significant decline in stomatal frequency, gossypol glands and trichome density was observed in mature leaves as compared to young leaves in the parents and their backcross derivatives. All the 69 individual lines (genotypes) of BC2F1 progeny differed significantly in stomatal frequency, trichome density, number of gossypol glands and lamina thickness; and hence their response to whitefly resistance. Correlation studies revealed a positive association of trichome density with whitefly incidence on G. hirsutum cultivars and developed backcross progeny. This relationship was observed in both young (r=0.319) and mature leaves (r=0.340). Higher hair density might allow strong grip of insects during oviposition and also their better retainment than on smooth leaves.This can be the reason of resistance in G. armourianum which is trichome less. The interspecific F1 hybrid having about 50 % of G. hirsutum genome exhibit short stellate trichomes but was highly resistant to whitefly. A positive correlation of stomatal frequency with other morpho-anatomical trait such as gossypol gland (ry=0.251 and rm=0.296) and with trichome density (ry=0.360 and rm=0.305) was observed in both young and mature leaves. Surprisingly, stomatal frequency on young leaves was positively correlated with whitefly infestation (r=0.372). Trichome angle varied non-significantly between young and mature leaves. No correlation of lamina thickness with whitefly incidence was observed in our study.Changes in levels of various biochemicals such as gossypol, phenolic, sugars, starch, proteins, tannins and chlorophyll content of leaf tissue were also determined in G. armourianum Acc. PAU1 along with G. hirsutum parents and susceptible check LH 2107 at periodic intervals (0 hrs, 12 hrs, 24 hrs, 48 hrs and 72hrs) after whitefly infestation. Gossypol contents were significantly lower in resistant G. armourianum than susceptible cultivar LH 1556 but was statistically at par to F1861 and LH 2107 on pooled basis. However, total phenols varied significantly when observed at periodic time intervals after B. tabaci infestation. The wild cotton G. armourianum had significantly higher tannin contents than G. hirsutum cultivars before infestation. The magnitude of increase was about 9 -fold when compared with susceptible check LH 2107. Further in response to whitefly infestation, leaf tannin levels declined initially at 12hrs and 24 hrs but then increased significantly at 72hrs. But surprisingly in G. armourianum, increase in tannin levels were observed much earlier i.e. after 24 hrs of infestation as compared to G. hirsutum varieties. Such an early upregulation of chemical induced resistance would be the reason for whitefly tolerance of this wild species.

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