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Abstract

The present experiment was conducted to estimate the physico-chemical diversity of twelve Indian jujube cultivars. A sum of fifteen quantitative characters were explored and subjected to multivariate analyses. Significant variability was observed across the ber cultivars under study. Pearson’s correlation analysis identified days to first flower initiation, a higher number of flowers per cluster and a higher number of retained fruits per cluster which could be used as the basis of selection for identification of high yielding ber cultivars. The principal component analysis (PCA) estimates 60.2% of the total variability in ber cultivars is contributed by PC1 and PC2. The scatter plot of the first two components highlights the number of retained fruits per cluster, yield per tree, pulp weight, fruit width, stone weight and number of flowers per cluster as principal characters that played a significant role in the total variability. Further, PCA also helped to identify Mehrun, Manuki and Chhuhara as superior ber cultivars which performed well with respect to the PC1 and PC2. The Mahalanobis D2 statistics grouped all the twelve ber cultivars into five clusters indicating the existence of ample genetic diversity among the cultivars. Considering the inter-cluster distance along with cluster mean it could be concluded that the cultivars of cluster II and Cluster III may be utilized to estimate the combining ability for effective exploitation of heterosis or to isolate desirable transgressive segregants.

In: Israel Journal of Plant Sciences
Author: Aneesha Singh

Abstract

Jatropha curcas is an important biodiesel plant as its seed contains 27–40% oil. The virus infection causes adverse effects on plant growth, and yield. The present study was carried out to develop plantlets from virus-infected plants using meristematic cultures. Cultures were also raised using nodal explant to figure out culture loss caused by the new strain of Jatropha leaf curl Gujarat virus (JLCuGV). Poor (48.3 ± 15.1 %) shoot bud induction was noted in virus-infected explants on MS medium supplemented with 6-benzylaminopurine (BAP) and Indole-3-acetic acid (IAA). Severe culture loss was noted upon subsequent sub-cultures of nodal explants. Apical meristem (MC) developed the highest (86.3 ± 12.5 %) shoot bud induction on Murashige and Skoog (MS) medium supplemented with 0.5 mg/L Thidiazuron (TDZ). Best results in shoot proliferation and elongation were achieved on 1.0 mg/L BAP, 1.5 mg/L IAA and 0.5 mg/L Gibberellic acid (GA3) containing medium with 9.9 ± 1.7 number of shoot buds of 5.2 ± 0.5 cm shoot length. It was interesting to note that the rooting percentage was not affected by virus infection. Shoots obtained from virus-infected and meristem cultures rooted well without any significant difference in rooting percentage. It was known by the study that the generation of planting material from virus-infected plants was possible with meristem explants but recalcitrant with nodal explants.

In: Israel Journal of Plant Sciences

Abstract

Azolla is a small freshwater fern reproduces sexually and asexually (by splitting). The spores’ formation through sexual reproduction in the azolla species is influenced by climatic condition. Keeping this fact in view, the present study was conducted with an aim to study the impact of temperature on the sporocarp formation and also developing storage techniques for sexual propagation in the azolla species. The study showed that the sporulation in Azolla pinnata was more sensitive to increase in the temperature than Azolla microphylla. Azolla pinnata did not sporulate on rising maximum temperature; however sporulation in Azolla microphylla was delayed by one month due to rise in the temperature during second year compared to the first year. Conversion of the freshly collected sporocarps into Azolla microphylla plants were decreased by 4.2–9.3% on increasing minimum and maximum temperatures by 5°C and 8°C, respectively and conversion of the one month old sporocarps into plants was decreased by 1.8–8.7% on rising minimum and maximum temperatures. On storing sporocarps in the refrigerator resulted in higher germination percentage than stored at room temperature. Conversion of freshly collected sporocarps into Azolla plants increased on storage of the sporocarps mixing with soil (1:15) in the refrigerator than at room temperature. Germination of one month old Azolla microphylla sporocarps on storage in refrigerator after mixing with soil decreased during second year compared to first year. Therefore, in a controlled environment, azolla may be encouraged to grow sporocarps for exploiting full potential of azolla for eco-friendly agricultural and livestock management.

In: Israel Journal of Plant Sciences

Abstract

The use of plants that present clear physiological responses to heavy metals such as cadmium (Cd) can assist in environmental monitoring. The aim was to evaluate physiological responses of Cd in Alternanthera tenella plants in micro-controlled conditions and to assess the its tolerance level and bioindicator potential. Nodal segments of A. tenella were grown in flasks containing semi-solid MS medium supplemented with (0, 50, 100, and 150 μM Cd). The total fresh and dry weight of the plants, in addition to physiological analyses, were determined after 30 days of cultivation. Plants submitted to Cd showed a reduction in biomass and photosynthetic pigments content. The decline in the Chl a/b ratio indicated the deleterious effects of Cd, as evidenced by the decrease in the density of active reaction centers (RC/CSM). The levels of deterioration in the functionality or structural integrity of the thylakoid membranes (WL) and the activity of the oxygen evolution complex (WK) increased as a function of Cd concentrations. The decreases in photochemical and non-photochemical quenching (qP and qN, respectively) observed in plants exposed to Cd indicated photochemical dysfunctions. Additionally, the increase in the quantum yield of non-regulated energy dissipation (ΦNO) indicated the presence of photodamage. Plants had a low/intermediate TI level (≥21.7) in the analyzed concentration range. A. tenella plants can bioaccumulate high amounts of Cd. The level of physiological responses of A. tenella is dependent on the concentration of Cd, which makes the use of this species even more promising as a bioindicator for this metal.

In: Israel Journal of Plant Sciences
Author: Akshay Mamgain

Abstract

This study highlights the importance of flower color variation and attraction as a mechanism for pollination and protection of floral parts. As part of this study, a survey relating to flower color variation and differences in spotting pattern (nectar guides) was conducted on Rhododendron arboreum, a widespread tree species in the mountainous region of Uttarakhand state, at 43 different altitudinal locations. Seven original color morphs of flowers and five types of spot variation in the nectar guide were observed. The study underlines the role of flower color polymorphism in both pollination and adaptation to varied environmental conditions. Further, the significance of nectar guides in directing the visitor to the reward is discussed. This study has the potential to enhance existing knowledge about flower color variation and attraction to the environment.

In: Israel Journal of Plant Sciences

Abstract

Groundnut is an important oilseed crops with high nutritional values. Yield of groundnut is constrained owing to diverse biotic and abiotic factors. Amongst biotic stresses two foremost foliar fungal diseases viz., late leaf spot and rust are universal and sparingly significant. Both conventional and modern breeding methods may be applied for improvement of groundnut. The current investigation was carried out to recognize genetic variability present among different groundnut germplasm with the use of morphological characters and SSR markers with the screening of resistant to leaf spot and rust resistant genotypes. In morphological examination, the analysis of variance divulged highly substantial differences among 48 germplasm lines. Initial screening of Germplasm was tried with the use of 125 SSR markers. But, based on banding pattern, 21 markers were found to be the best and selected for amplification of whole set of genotypes. Out of 21 markers, 16 were found to be highly polymorphic. Highest PIC value (0.8196) was detected for marker S021 representing 81% diversity. SSR Markers viz., PM42, PM204, PM377, S052, S076, S078 and S078 have PIC value more than 0.5, confirms their superiority in detection of polymorphism among studied germplasm lines. UPGMA analysis assemblage all the germplasm lines into three major clusters. Most of the foliar disease resistant genotypes were grouped together with higher genetic resemblance. Polymorphic markers identified in the study may be utilized further for molecular diversity analysis and the identified resistant genotypes may be employed further for the improvement of the crop.

In: Israel Journal of Plant Sciences

Summary

Reaction wood formation (tension wood) in trees such as poplar is a response to stress and environmental factors. Tension wood is a rich source of cellulose that can be used for products including paper or biofuels and is thus a target product in forestry. This study aimed to evaluate the formation of tension wood in two-year-old saplings of Populus alba by using alternate bending, nitrogen fertilization, and gibberellin hormone. Saplings were bent alternately in one or another direction every month during the growing season, fertilized twice at the beginning and in the middle of the growing season, and treated with gibberellin early in the growing season. The physical and anatomical characteristics of the wood were studied after the end of the growing season. Evaluation of transverse sections of specimens stained with safranin/Astra-blue showed that, compared with straight saplings, alternate bending saplings had a wider tension wood area in the growth ring and clear formation of a gelatinous layer. The wood of alternate bending saplings with nitrogen fertilization and gibberellin hormone had a higher wood density, greater longitudinal shrinkage, and less radial and tangential shrinkage than saplings with other treatments. Moreover, the alternate bending saplings treated with nitrogen fertilization and gibberellin hormone had tension wood with the largest vessels, the lowest vessel density, and the smallest total vessel lumen area than saplings with other treatments. Wood fibers of treated saplings also had the thickest wall with the smallest fiber and lumen diameters. Overall, the bending treatment with the addition of nitrogen fertilization and gibberellin hormone was the most effective for the stimulation of tension wood formation in terms of volume and intensity.

In: IAWA Journal

Summary

The tribe Diosmeae (Rutaceae) encompasses circa 278 species classified in 11 genera: ten of them are shrubs endemic to the Cape Floristic Region (South Africa), while the only arborescent genus (two species) extends from South Africa to Tanzania. We examined the wood structure of 21 species representing nine genera of Diosmeae and analysed it with respect to their life form and climatic niches. Studied taxa share a suite of traits typical for the whole family: radial vessel multiples, simple perforation plates, minute alternate intervessel pits, distinctly bordered vessel-ray pits, non-septate libriform fibres, and — except for Empleurum — marginal axial parenchyma. However, unlike most Rutaceae, they also occasionally feature vessel-ray pits with reduced borders. Most of the studied species are very similar to each other in their wood structure and habit. The two exceptions are Calodendrum capense (the only canopy tree under study) and Empleurum unicapsulare (a large riparian shrub). The first differs from other species in having wider vessels, longer libriform fibres, prismatic crystals in ray cells and winged-aliform axial parenchyma (which may be plesiomorphic for the tribe); the latter is distinctive because it lacks growth rings and banded axial parenchyma. Analysing anatomy–climate relationship, we found that wood anatomy among shrubby Diosmeae relates to their size and environmental factors, rather than taxonomy. Particularly, the vessel grouping weakly increases with stricter water limitation along the gradient from a semi-arid winter-dry climate to a Mediterranean winter-wet climate.

In: IAWA Journal

Abstract

Our field research in Van province during 2008–2009 resulted in collection of 3766 lichen samples from 55 sites, and identification of 229 lichen taxa, including two subspecies and three varieties, in 108 genera of Ascomycota. We found 182 new records for Van province. These include four new records for Turkey, namely Bibbya ruginosa, Buellia subalbula, Caloplaca tenuatula and Rimularia gibbosa. Lists of species and collection sites are provided. Acarospora (11 species), Lecidea (9 species), Verrucaria (8 species), Caloplaca, Physcia and Rinodina (7 species for each), and Aspicilia, Lecanora and Polyozosia (6 species for each) are the genera richest in species in the study area. Of the identified species, 163 are crustose, 43 are foliose, 7 are fruticose, 13 are squamulose and 3 are leprose. 101 species colonise on calcareous rocks, 86 on siliceous rocks, 23 on various trees (epiphytic), 10 on soil, 12 on moss and 17 on other lichens (lichenicolous). Sites 16, 19 are the richest with 55 identified taxa, followed by sites 52, 34, and 6 with 51, 49 and 44 taxa, respectively. The poorest sites are 40 and 42 with 6 identified taxa, followed by sites 5, 7, and 21 with 8, 8, and 9 taxa, respectively.

In: Israel Journal of Plant Sciences

The editors and associate editors of IAWA Journal offer a sincere thank you to our many expert reviewers, on behalf of all our authors, and readers, for their commitment to providing thoughtful and constructive reviews. We wish to thank the following colleagues for reviewing manuscripts submitted to or published in the IAWA Journal in 2021:

Hisashi Abe

Clemens Altaner

Rafael Arevalo

Pieter Baas

Alexandre Bahia Gontijo

John Barnett

Hans Beeckman

Peter Kitin

Leonardo Bona do Nascimento

Gerd Bossinger

Anaïs Boura

Mariana Brea

Marco Carrer

Caroline Cartwright

Sergio Cevallos-Ferriz

Eliezer Cocoletzi

Warlen Costa

Israel Lopes Cunha Neto

Geoffrey Daniel

Veronica DeMicco

In: IAWA Journal