Primary Shoot Research Articles

Evaluation of Kabuli Chickpea Genotypes for Tropical Adaptation in Northern Australia

Chickpea is one of the economically important legume crops adapted for winter season production in tropical climates. This study evaluated the physiological, morphological, and biochemical traits of eight Kabuli chickpea genotypes in an Australian tropical environment. The result revealed significant differences between genotypes for seed emergence, plant height, primary shoots, leaf number, leaf area index, gas-exchange parameters, seed yield, carbon discrimination (Δ13C), and natural abundance for nitrogen fixation. Among the tested genotypes, AVTCPK#6 and AVTCPK#19 exhibited late flowering (60–66 days) and late maturity (105–107 days), and had higher leaf photosynthetic rate (Asat) (28.4–31.2 µmol m−2 s−1), lower stomatal conductance (gsw) (516–756 mmol m−2 s−1), were associated with reduced transpiration rate (T) (12.3–14.5 mmol m−2 s−1), offered greater intrinsic water-use efficiency (iWUE) (2.1–2.3 µmol m−2 s−1/mmol m−2 s−1), and contributed a higher seed yield (626–746 g/m2) compared to other genotypes. However, a larger seed test weight (>60 g/100 seed) was observed for AVTCPK#24, AVTCPK#8, and AVTCPK#3. Similarly, a high proportion (45%) of larger seeds (>10–11 mm) was recorded for AVTCPK#24. Furthermore, a higher %Ndfa in AVTCPK#6 (71%) followed by AVTCPK#19 (63%) indicated greater symbiotic nitrogen fixation in high-yielding genotypes. Positive correlation was observed between %Ndfa and seed protein, as well as between seed yield and plant height, primary shoots, leaf count, leaf area index, leaf photosynthesis, stomatal conductance, transpiration rate at pod filling stage, biomass, and harvest index. An inverse correlation between (Δ13C) and iWUE, particularly in AVTCPK#6 and AVTCPK#19, indicates greater heat and drought tolerance, required for high-yielding Kabuli chickpea production in northern Australia.

Dry Leaf Biomass Stability of Stevia (Stevia rebaudiana) Clones over Different Environments

In order to identify stable high-yielding stevia (Stevia rebaudiana) genotypes, a multi-environment testing was conducted over four different growing environments. The experiments were conducted in a randomized block design, with three replications during 2019 and 2020. The combined analysis of variance showed significant variation for genotype, environment, and G×E interaction for all studied traits. The highest mean performance for all the traits revealed that Hoshiarpur has favorable conditions for stevia cultivation, and CSIR-IHBT-ST-1801 followed by CSIR-IHBT-ST-G12 were the best performers over all the locations. The Eberhart and Russell model-based stability parameters demonstrated that CSIR-IHBT-ST-1801 was a stable performer for dry leaf biomass, and that was also further confirmed by GGE biplot analysis. Primary shoots were major contributors to the dry leaf biomass, as indicated by the substantial positive leaf biomass contribution shown by Pearson's correlation coefficients. As a result, primary shoots might be utilized as selection criteria to increase the dry leaf biomass. The CSIR-IHBT-ST-1801 could be used as a stable high-yielding variety for the targeted regions and also, can be used for further stevia breeding programs.

Genetic diversity analysis and molecular characterization of tropical rose (Rosa spp.) varieties

Characterization of rose varieties becomes essential for understanding, utilizing, and preserving the diversity among them, for their genetic improvement, cultivation, and conservation. With this purpose, 19 tropical rose varieties were evaluated via quantitative morphological and molecular markers. A significant degree of variation was observed across nearly all descriptors, suggesting a notable level of genetic diversity among the released rose varieties. Traits like flower diameter, flower yield/plot, and shelf life, considered to be of vital importance given the aesthetic value of rose, exhibited remarkable differences that would further aid in the selection of desirable varieties. The maximum flower diameter, flower yield/plot, and shelf life were recorded in Yellow Page, Lambada, and Delhi Princess, respectively. The varieties were evaluated by correlation matrix, hierarchical agglomerative clustering method-based dendrogram, network plot on phenotypic correlation, colour intensity graph including Red-Green-Blue (RGB) scattered plot. In the correlation matrix, it was found that more number of primary shoot contributes to higher flower yield, while increase in leaf area degraded the shelf life of the flower. Realizing the importance of molecular characterization, 10 selected polymorphic inter simple sequence repeats (ISSR) and start codon targeted (SCoT) polymorphism primers were tested that amplified total 187 polymorphic loci with 94.4 % polymorphism. Cent percent polymorphism were found with SCoT-2, SCoT-18, SCoT-19, HB-12 and ISSCR3 primers. A principal component analysis based on molecular diversity highlighted that First Red, Local Selection 2, and Himroz exhibited distinct characteristics compared to the other varieties. The 19 varieties were grouped into 8 clusters viaunweighted pair group method with arithmetic mean-based dendrogram at 0.4 similarity co-efficient. The analysis revealed a significant genetic distance between Himroz, First Red, and Grand Gala, suggesting their potential to be utilized in hybridization programs for crop improvement. The distinguishable genetic background and high degree of variation revealed by molecular markers, specifically ISSR and SCoT, offer valuable insights that can contribute to the strategic improvement of roses. These findings provide a foundation for expediting rose breeding programs and comprehensive crop improvement strategies.

Exogenous application of different antagonists and their secretory metabolites to manage root-knot nematodes in pea

Pea (Pisum sativum L.) is a grain legume, a member of the Leguminosae family. Root-knot nematodes cause severe losses ranging from 15 to 85%. Different species of nematodes including root-knot nematodes reduce the yield of pea significantly. To control root-knot nematodes biological control is a more environment-friendly approach. The main objective of the study is to assess the effect of different antagonistic microbes and their secretory metabolites to manage root-knot nematodes in peas. Through this research, we aim to identify potential biological control agents that can be used as eco-friendly alternatives to chemical nematicides, contributing to sustainable pest management practices in agriculture. For this purpose, firstly, a brinjal seedling was transplanted for inoculum development which was inoculated with infective 2nd stage juveniles of root-knot nematodes (Meloidogyne spp.) in Department of Plant Pathology research area, University of Agriculture Faisalabad (UAF). Then two pea varieties viz. Matar sabaz and Pea-2009 were sown in pots and inoculated with nematode larvae after four weeks of sowing. Moreover, the management of nematodes was done by using the antagonists and their secretory metabolites application. The data of different plant growth and nematode-related parameters was taken and subsequently analyzed using analysis of variance and least significant difference test (LSD). Results showed that the antagonist’s treatment subsequently controlled root-knot nematodes (RKNs). Maximum plant/shoot length (47 cm), root length (25.25 cm), shoot weight (22.25 g) pod length (8.50 cm), No. of secondary shoots (8) and minimum number of galls (2.5 cluster), was observed in plants treated with Bacillus spp. (T1) while maximum No. of fruits (5.75) was observed in plants treated with Pseudomonas spp. (T2). Similarly, the number of nodules (7.50 clusters) primary shoots (5) Root weight (4.6 g) was observed in plants treated with Enterobacter spp. (T3).

Obtaining Glycyrrhiza uralensis “hairy” roots: primary assessment of growth characteristics and content of phenolic compounds

Widespread use and uncontrolled harvesting of wild plants of Ural licorice (Glycyrrhiza uralensis Fisch. ex DC.) as a raw material for pharmacology and the food industry determines the promise of the system of “hairy” roots for obtaining valuable secondary metabolites. The aim of the research is to develop an effective protocol for the agrobacterial transformation of Rhizobium rhizogenes of various types of explants of 30-day-old G. uralensis microplants: cotyledons, primary shoots, hypocotyls, and primary roots. The effect of 100 цМ acetosyringone, variation of the cocultivation time (2 and 4 h) on the efficiency of the transformation process by two strains of R. rhizogenes 15834 SWISS and MSU 440 was studied. infection (2 h) and competent types of explants for transformation with the strain (cotyledons, primary shoots, primary roots). As a result of primary selection, 12 lines of stably growing BK cultures were selected. PCR analysis showed that all selected lines contain the rolB and rolC genes, while the virC gene is absent. It was determined that 4 lines are characterized by a high growth rate, 3 are characterized by a high total content of phenolic compounds. To the best of our knowledge, this is the first protocol for obtaining a culture of hairy roots from G. uralensis using strains R. rhizogenes 15834 SWISS and MSU 440.

Фенотипическая и генетико-селекционная оценка березы повислой (Betu-la pendula ROTH) и березы пушистой (Betula pubescens EHRH.) ex situ и in vitro

The results of a study of birch test cultures obtained by different methods of ex situ pollination and introduced into culture in vitro are presented. To identify the phenotypic, cultural and cytological characteristics of two birch species naturally growing in the Central Black Earth Region - silver birch (diploid) and downy birch (tetraploid), test cultures of seed origin F1 and F2 were specially created. The article presents data on phenotypic (growth in height in the juvenile and reproductive periods of ontogeny), genetic selection (seed propagation system) variability and some characteristics of the introduction of F1 seed progeny of breeding forms of local birch species into in vitro culture. To predict the growth characteristics of seed progeny of breeding forms of local birch species obtained by different methods of pollination - self-pollination and open pollination at different stages of ontogeny (at the age of 2 and 10 years), a statistical processing of the feature of growth in height of families was carried out using the rank Spearman's correlation coefficient ρ. Species specificity was shown in response to different pollination methods, morphogenic activity of self-fertile and self-sterile forms of these birch species on a nutrient medium ½ MC + 6-benzylaminopurine 1 mg/l, primary shoot formation of explants and regenerative capacity in these species, the nature of morphogenesis (formation of the main escape). For the polyploid species (downy birch), a higher level of self-fertility was established, as well as a more intensive growth of shoots in height than for drooping birch; primary explants in the former had a different character of morphogenesis (there was a joint initiation of the main shoot with adventitious ones) than in silver birch (formation of the main shoot), which indicates a greater adaptive potential for polyploid species and their greater opportunities for inclusion in genetic breeding experiments and obtaining valuable breeding forms.

Renewal Pruning Alone or in Combination with Thinning Pruning Affects Growth, Fruit Yield and Fruit Quality of Aroniaberry

Aroniaberry (Aronia mitschurinii) produces small pome fruits that possess health promoting compounds. Management practices for orchards are lacking, since aroniaberry is a relatively new crop. Pruning is an important cultural practice to optimize fruit yield in orchards. The response of an established aroniaberry orchard to pruning was evaluated over three years (2020 to 2022). Pruning treatments were as follows: 1) renewal pruning (removal of shoots to the base) only in year 1; 2) renewal pruning in year 1 + thinning to 18 shoots in year 2; 3) renewal pruning in year 1 + thinning to 9 shoots in year 2; and 4) no-pruning (control). In response to renewal pruning, plants grew uniformly and vigorously, producing 28 new vegetative primary shoots with an average length of 66 cm by the end of the first growing season. Limited flowering and fruiting occurred in the second season for plants receiving pruning treatments. Fruit yield on pruned plants was significantly less than for unpruned controls. In season 2, increased thinning of renewal-pruned plants negatively affected the number of inflorescences per plant, but positively affected individual fruit fresh weight and fruit °Brix:titratable acidity ratios. Fruits from all treatments had similar monomeric anthocyanins, total phenolics and mineral content. In season 3, flower production and predicted fruit yield from pruned plants and unpruned controls were similar, even though pruned plants were substantially smaller. In the third season, there were no longer any differences between renewed + thinned plants and those that received only renewal pruning, making shoot thinning an unnecessary practice. The results of this study demonstrate that renewal pruning can be an effective way to manage and rejuvenate an aging aroniaberry orchard.

Is Twelve Hours Really the Optimum Photoperiod for Promoting Flowering in Indoor-Grown Cultivars of Cannabis sativa?

Cannabis sativa ("cannabis" hereafter) is a valuable recent addition to Canada's economy with the legalization for recreational use in 2018. The vast majority of indoor cannabis cultivators use a 12-h light/12-h dark photoperiod to promote flowering. To test the hypothesis that robust flowering initiation responses can be promoted in indoor-grown cannabis cultivars under longer photoperiods, clones of ten drug-type cannabis cultivars were grown under six photoperiod treatments. All treatments were based on a standard 24-h day and included 12 h, 12.5 h, 13 h, 13.5 h, 14 h, and 15 h of light. The plants were grown in a growth chamber for 3 to 4 weeks, receiving an approximate light intensity of 360 µmol·m-2·s-1 from white LEDs. Flowering initiation, defined as the appearance of ≥3 pairs of stigmas at the apex of the primary shoot, occurred in all cultivars under all photoperiod treatments up to 14 h. Delays in flowering initiation time under 14 h vs. 12 h ranged from no delay to approximately 4 days, depending on the cultivar. Some cultivars also initiated flowering under 15 h, but floral tissues did not further develop beyond the initiation phase. Harvest metrics of some cultivars responded quadratically with increasing photoperiod, with ideal levels of key flowering parameters varying between 12 h and 13 h. These results suggest there is potential to increase yield in some indoor-grown cannabis cultivars by using longer than 12-h photoperiods during the flowering stage of production. This is attributed to the inherently higher daily light integrals. Indoor cannabis growers should investigate the photoperiod responses of their individual cultivars to determine the optimal photoperiod for producing floral biomass.

Effects of Planting Pre-Germinated Buds on Stand Establishment in Sugarcane

Sugarcane (a complex hybrid of Saccharum spp.) is propagated vegetatively by using stem pieces of mature cane with healthy buds. Abiotic and biotic stress may cause pre-germination of these buds, which may have an impact on both emergence and plant cane stand establishment. There is very limited information available in the literature. A greenhouse study was conducted with single-budded seed pieces of three levels of bud germination (ungerminated buds, Pop-eyes, and Lalas) from three different cultivars (CP 96-1252, CPCL 05-1201, and CPCL 02-0926) planted in pots and repeated over time. Data on growth parameters (tiller count, primary shoot height, SPAD, and dry biomass of shoots and roots) at early growth showed that Lalas produced more tillers and higher shoot dry biomass than Pop-eyes and ungerminated buds. Both Lalas and Pop-eyes produced higher root dry biomass than ungerminated buds in one of the two experiments. The cultivar had a significant effect on primary shoot height and SPAD. A small plot field experiment was conducted with cultivar CP 96-1252 to validate the results of greenhouse experiments, and similar results were reported for tiller count. The results indicate that pre-germinated buds may have a neutral or positive effect on early sugarcane growth and establishment. Further on-farm research needs to be conducted to confirm these results before using pre-germinated buds as a potential seed source for the late season planting of sugarcane.

‘Miguang’ Grape Response to Pergola and Single-Curtain Training Systems

Background and Aims: Grapevine shoot growth and light utilization are typically adjusted through the use of canopy management strategies that are adapted to the local climate. In this study, we analyze the effects of a pergola (PER) and single-curtain training system (SCT) on the microclimate, light interception, photosynthetic capacity, and assimilate distribution of ‘Miguang’ grape in a rainy region of China. Methods and Results: We measured light interception, spectral absorptance, leaf area, chlorophyll content, photosynthetic rate, soluble sugar and starch content per cane, assimilate distribution berry weight, soluble solids, and titratable acid content. SCT produced a higher photosynthetic photon flux density in the cluster region, a canopy light absorptance in the 450–800 nm wavelength range, higher chlorophyll content, and larger leaf area of the middle node leaves. It produced lower basal and top leaves leaf areas. At berry expansion (E-L-31) and veraison (E-L-35), the net photosynthetic capacity of the leaves from the base to the middle nodes was higher with SCT than with the PER, and the net photosynthetic capacity of leaves near the top was reduced with SCT. At the harvest period, the net photosynthetic rate of the middle and top node leaves and the shoot photosynthetic rate were higher with SCT than with the PER. The distribution of assimilates to the fruit was higher with SCT. In addition, SCT produced a higher shoot soluble sugar and lower internode length from the fourth to sixth nodes, and it produced a higher shoot starch content and internode diameter in the fourth internode. Conclusions: SCT significantly improved photosynthetic photon flux density in the cluster, promoted assimilate distribution to fruit, decreased vegetative growth, increased chlorophyll content, increased the leaf size of the middle node on the primary shoot, and increased shoot soluble sugar from the fourth to sixth nodes. Significance of this Study: The results of this study can provide a relevant theoretical basis and technical support for grape canopy management.

Post-Spring Frost Canopy Recovery, Vine Balance, and Fruit Composition in cv. Barbera Grapevines

Background and Aims. In viticulture, one of the effects of warming trends is the advance of budburst date and the consequent increased risk of spring frost-related damage. In 2021, severe frost events affected a large fraction of European viticulture. In a cv. Barbera vineyard, located in NW Italy, primary bud shoots (PBS), secondary bud shoots (SBS), and suckers (SK) were tagged after the occurrence of freezing temperatures in spring. The goal of the study was to clarify if SBS could partially restore yield loss and analyze their contribution to fruit composition. Methods and Results. The number of developing SBS and SK correlated with the number of killed PBS. While PBS bore 1.44 inflorescences per shoot, SBS had much lower fertility (0.4), with SK at intermediate levels (0.85). The vine yield was 40% of the previous season, with SBS bunches contributing just 17% of the total. SBS produced smaller and looser bunches, as compared with PBS (−28% mass and −27% compactness). At harvest, no difference was found in grape total soluble solids (TSS) among different shoot types. However, the TSS average was notably higher than that observed in the previous season (27.8°Brix vs. 23.3°Brix in 2020). Interestingly, while in PBS and SK, a direct correlation (linear and quadratic, respectively) existed between the leaf area to yield ratio (LA/Y) and grape TSS or total anthocyanins, this did not occur for SBS. Conclusions. In the case of spring frost damage, the number of PBS avoiding fatal injuries will drive agronomic results at harvest since SBS contribution to total yield is modest due to low shoot fruitfulness. The frost-induced increase in vine LA/Y leads to a dramatic rise in grape TSS and phenolics. Significance of the Study. When spring frosts kill a significant number of primary shoots, an altered grape composition at harvest should be expected due to changes in vine balance. Therefore, the vineyard management should be adjusted accordingly early in the season. Further studies are needed to test specific post-frost canopy management strategies ensuring yield, optimal fruit composition, and cane renewal.

In Vitro Evaluation of the Effects of BAP Concentration and Pre-Cooling Treatments on Morphological, Physiological, and Biochemical Traits of Different Olive (Olea euorpea L.) Cultivars

In vitro propagation of olive (Olea euorpea L.) always remained a challenging task due to its woody nature and oxidation of culture. The current study intended to optimize shoot induction and proliferation protocol for different cultivars (“Leccino”, “Gemlik”, “Moraiolo” and “Arbosana”) of olive-on-olive media (OM) provided with different concentrations (0, 0.5, 1.5, and 2.5 mgL−1) of 6-benzylaminopurine (BAP) by pre-exposing their explants (nodal segments) with different regimes (0, 24, and 48 h) of cooling. The impacts of treatments were evaluated on morphological (shoot induction percentage, primary shoot length, number of leaves shoot−1, and number of shoots per explant−1), physiological (total chlorophyll, carotenoids, CO2 assimilation, and proline), biochemical (primary and secondary metabolites) attributes of cultivars after 50 to 60 days of culture. Data recorded were subjected to statistical analysis. All traits depicted significant increases in all genotypes with increasing pre-cooling treatments and increasing supplementations of 6-benzylaminopurine (BAP). This increase was the highest for the interaction of 48 h pre-cooling and 2.5 mgL−1 BAP concentration. Moreover, correlation analysis of all traits revealed significant paired association among them in a positive direction, while principal component analysis (PCA) revealed the extent of association varied with types of treatments and the nature of genotypes. Among cultivars, Arbosana depicted more dramatic changes in morphological traits, physiological attributes, and biochemical contents due to varying interactions of pre-cooling and BAP treatments as compared to Moraiolo, Gemlik, and Leccino with in vitro systems.

Genome-Wide Identification and Expression Analysis of Senescence-Associated Genes in Grapevine (Vitis vinifera L.) Reveal Their Potential Functions in Leaf Senescence Order.

Natural leaf senescence is an acclimation strategy that enables plants to reallocate nutrients. In the present study, interestingly, we found that the basal mature leaves of grapevine primary shoots (P) exhibited the earliest senescence, followed by the apical young leaves of secondary shoots (ST), and then the basal mature leaves of secondary shoots (S). The Chl level decreased with the extent of leaf senescence. According to the genome-wide identification and expression analysis, sixteen senescence-associated genes (SAGs) involved in Chl breakdown were identified in the grapevine genome. Their expression patterns showed that the transcript changes in VvSGR, VvPPH2, and VvFtsH6-2 corresponded to the changes in Chl content among P, S, and ST. The changes in the transcription of VvNYC1, VvSGR, VvPAO1, VvPAO2, VvPAO4, VvPPH1, VvPPH3, and VvFtsH6-1 only contributed to low Chl levels in P. The cis-element analysis indicated that these SAGs possessed several light- and hormone-responsive elements in their promoters. Among them, ABA-responsive elements were found in twelve of the sixteen promoters of SAGs. Correspondingly, ABA-signaling components presented various changes in transcription among P, S, and ST. The transcription changes in VvbZIP45 and VvSnRK2.1 were similar to those in VvSGR, VvPPH2, and VvFtsH6-2. The other nine ABA-signaling components, which included VvRCAR2, VvRCAR4, VvRCAR6, VvRCAR7, VvRCAR2, VvPP2C4, VvPP2C9, VvbZIP25, and VvSnRK2.3, were highly expressed in P but there was no difference between S and ST, with similar expression patterns for VvNYC1, VvSGR, VvPAO1, VvPAO2, VvPAO4, VvPPH1, VvPPH3, and VvFtsH6-1. These results suggested that the senescence of P and ST could be regulated by different members of Chl breakdown-related SAGs and ABA-signaling components. These findings provide us with important candidate genes to further study the regulation mechanism of leaf senescence order in grapevine.

Prolonged Exposure to High Temperature Inhibits Shoot Primary and Root Secondary Growth in Panax ginseng.

High temperature is one of the most significant abiotic stresses reducing crop yield and quality by inhibiting plant growth and development. Global warming has recently increased the frequency of heat waves, which negatively impacts agricultural fields. Despite numerous studies on heat stress responses and signal transduction in model plant species, the molecular mechanism underlying thermomorphogenesis in Panax ginseng remains largely unknown. Here, we investigated the high temperature response of ginseng at the phenotypic and molecular levels. Both the primary shoot growth and secondary root growth of ginseng plants were significantly reduced at high temperature. Histological analysis revealed that these decreases in shoot and root growth were caused by decreases in cell elongation and cambium stem cell activity, respectively. Analysis of P. ginseng RNA-seq data revealed that heat-stress-repressed stem and root growth is closely related to changes in photosynthesis, cell wall organization, cell wall loosening, and abscisic acid (ABA) and jasmonic acid (JA) signaling. Reduction in both the light and dark reactions of photosynthesis resulted in defects in starch granule development in the storage parenchymal cells of the main tap root. Thus, by combining bioinformatics and histological analyses, we show that high temperature signaling pathways are integrated with crucial biological processes that repress stem and root growth in ginseng, providing novel insight into the heat stress response mechanism of P. ginseng.

Effect of Shoot Pruning on Growth, Flowering and Fruiting Characteristics of Different Guava (Psidium Guajava L.) Cultivars

ABSTRACT A field trial was conducted to study the effect of shoot pruning on growth, flowering and fruiting characteristics of different guava cultivars. The experiment was carried out during Jan. 2018 to June 2019. The experiment was laid out in Randomized Block Design (RBD) with seven cultivars as treatments including L-49 (T1), Allahabad Safeda (T2), Baruipur (T3), Doodh Khaja (T4), Kafri (T5), Bhagalpur (T6) and Harichal (T7). Shoot pruning in guava is an alternative practice used to control the excessive growth and vigor of the plant. The plants were pruned from 120 cm above the ground level as heading back to facilitate the production of new shoots from below the cut point and allow the primary shoots. These results revealed that, guava cultivar baruipur was best in terms of number of primary shoots (58.17), length of primary shoots (135.82 cm) at 12 months after pruning, flowering percentage (66.11%) and better fruit characteristics.

Thuja ×soeegaardii (Cupressaceae) – a new name for an old hybrid

Thuja ×soeegaardii, a hybrid of Th. plicata Donn ex D.Don and Th. standishii (Gordon) Carrière, is described as a new nothospecies from the Kórnik Arboretum, Poland, based on plants obtained in 1988 from the Botanical Garden in Gothenburg, Sweden. The hybrid was found for the first time at the Hørsholm Arboretum, Denmark, in 1938, among seedlings grown from seeds collected from Thuja standishii. Plants grown from rooted scions of this hybrid were planted in several places within the Hørsholm Arboretum. Soon, the hybrid plants were gifted to the Botanical Gardens in Copenhagen and Gothenburg as well to the Poulsen’s Plant Nursery in Kvistgård. In 1967 seedlings were sent from Kvistgård to the National Ar­boretum in Washington, where one of them developed into a particularly showy, lush and vigorous plant characterized by a dense, narrow, conical crown. The offspring obtained from rooted scions turned out to be very drought and wind-resistant, especially suitable for the formation of tall hedges and windbreak screens. This plant, now very widespread in cultivation, especially in the United States, goes by the name of Thuja ‘Green Giant’. In terms of morphology, many features of Th. ×soeegaardii are intermediate as compared to the parent species. From the Th. plicata, it differs by the following characteristics: leaves not or only weakly shining above, lateral leaves with inwardly curved (not straight) apices, the apical part of lower central leaves thickened and slightly bent from the stem (not appressed), glands on central leaves only weakly vis­ible, central leaves of primary shoots acuminate (not long acuminate) and seed wings sparsely papillose in the upper part (only rarely smooth). From Th. standishii, it can be distinguished by the less glaucous upper leaf surface, the less protruding apical part of lower central leaves, at least faintly visible glands on central leaves, acuminate (not acute) central leaves of primary shoots and less distinctly papillose upper part of seed wings.

Response of Shoot Pruning on Growth, Flowering and Fruiting Characteristics of Guava under Sub-Himalayan Terai Region of West Bengal

Guava is one of the important fruit crops grown worldwide. Shoot pruning improves the emergence of new flush and its role on flowering and fruiting characteristics was evaluated on this experiment. The effect on shoot pruning height and removal of top leaf bud by pinching was assessed on growth, flowering and fruiting characteristics of guava cv. L-49. The experiment was conducted at Uttar Banga Krishi Viswavidyalaya There were two factors heading back and pinching. Heading back at the level of, Pundibari, Cooch Behar, West Bengal. 90, 120 and 150cm was done in January and pinching of one leaf pair was performed during the last week of June, 2018.The heading back at the level of 120 cm and no pinching were most effective for number of flowering bud (179.33), number of flowers (139.83), number of fruit set (95.33), total number of fruits (64.66), ascorbic acid (190.35 mg/100g), titratable acidity (0.28%) and heading back at the level of 120 cm and one pinching were effective in increasing number of primary shoots (39.50), flowering percentage (80.18%), fruit weight (172.00g).

Investigation of the species composition and harmfulness of dominant phytophages of onions in the Right-Bank Forest-Steppe of Ukraine

The research is aimed at studying the species composition, dynamics of the number and harmfulness of dominant pests, which is extremely important for the development and improvement of elements of the onion protection system. After all, the analysis of literature sources showed insufficient information about the distribution and harmfulness of the main phytophages under modern conditions of growing onions in the Right Bank Forest-Steppe of Ukraine.
 We conducted the monitoring of the phytosanitary condition of onion crops during 2017–2020 and determined the species composition of dominant phytophages. We studied the complex of soil pests: larvae of Melolontha sp., the population density of which over the years of research was 0.8–2.5 specimens/m2, larvae of Elateridae sp., or click beetles (wireworms) – 0.9–2.2 specimens/m2 and Gryllotalpa gryllotalpa L. – 2.5 specimens/m2. Dominant species of phytophages in onion crops included onion fly (Delia Antigua Mg.), onion thrips (Trips tabaci Lind.), and Ceuthorrhynchus jakovlevi Schultze.
 The four most vulnerable phases of growth and development of onions before colonization and damage by major phytophages were identified:
 1) phase of leaf development (a primary shoot) (ВВСН 1–19);
 2) phase of the beginning of thickening of leaf base – bulb formation (ВВСН 41–43);
 3) phase of bulb formation – beginning of leaf splitting (ВВСН 45–47);
 4) phase of the completion of growth and development (state of physiological rest) (ВВСН 48–49)

Evaluation of Potentiality of Different Mango Genotypes for Flowering, Fruiting and Yield of fruits under the Red and Lateritic Zone of West Bengal

The present investigation was carried out at mango orchard of Rathindra Krishi Vigyan Kendra, near Palli-Siksha Bhavana (Institute of Agriculture), Sriniketan, Visva- Bharati, West Bengal, during the period of 2014- 2015 to study the potentiality of different cultivars of mango with regards to flowering, fruiting and yield of fruits. Total nine mango cultivars namely, Amrapali, Mallika, Kohitur, Ranipasand, Golabkhas, Bombai, Kohinoor, Enayat pasand and Safdar pasand were selected. One mango tree represents a single replication and each treatment or a cultivar was replicated three times. The observations were recorded as tree height(cm), tree spread(cm), trunk girth shoot length(cm), shoot girth (cm), primary shoot girth (cm), number of panicles per branch, length of panicle at anthesis, full bloom period (days), number of fruits per panicle at maturity, number of fruits per tree and fruit yield (kg/tree). Amongst all the evaluated Cv. Mallika, Golabkhas and Kohinor was found to be superior under the red and lateritic zone of West Bengal. As per the result found these identified cultivar may be considered as a good donor for hybridization programme to evolve the superior varieties and can be recommend for commercial multiplication and production specially under the red and lateritic zone of West Bengal.

Astragalus penduliflorus Lam. hairy roots: A promising biotechnological platform for obtaining anti-influenza drugs

The rapid emergence of influenza virus A resistance to current antivirus drugs has raised an urgent need for developing safe and effective remedies based on plants. Hairy roots are considered an efficient system for the large-scale production of valuable compounds with potent antiviral activity. We have evaluated for the first time an antivirus activity in Astragalus penduliflorus Lam. hairy roots (APHRs) lines obtained from cotyledons (APHR 2), primary shoots (APHR 5), and hypocotyls (APHR 6) against influenza A/Aichi/2/68 (H3N2) and A/chicken/Kurgan/05/2005 (H5N1) subtypes. Estimation of the antiviral activity was based on the analysis of cytotoxic activity, selectivity and neutralization indexes. All tested samples demonstrated low toxicity for MDCK cell culture corresponding to the modern requirement for antiviral drugs. Index neutralization (IN) was 2.50 in APHR 2, 28 d extract against H3N2 subtype, whereas the highest IN against H5N1 (2.25) was detected for line APHR 5 56 d The levels of selectivity index observed in APHR 5, and APHR 6 were higher in comparison with APHR 2, corresponding to the level of antioxidants, determined by the DPPH radical scavenging assay and total antioxidant activities by amperometric method. Major phenolic compounds identified in APHRs lines extracts by HPLC analysis, including flavonoids, hydroxybenzoic, hydroxicinnamic acids, could be responsible for the antiviral activities.