Basal Leaf Sheaths Research Articles

Influence of stem and leaf phenotypes, physiological responses and cellular ultrastructure on defoliated sugarcane cultivars

Defoliation is a primary agronomic traits, its variation depends on different plant species or cultivars. The present article assess the leaf morphological responses, oxidative metabolites and enzymatic activities at sheath base of sugarcane cultivars during defoliation stage of plant leaves. The mature leaf sheath of GT47 strongly wrapped to the stem, and no stem was exposed. The upper and lower edges of the immature fusing abscission zone were parallel, and slightly lower browning area (+ 3 to + 7 leaf position). The ROC22 cultivar was monitored highest leaf sheath-based cellulose and lignin content, followed by GT60 and GT47. Peroxidase activity was higher in leaf sheath base edge (ROC22) as compare to other cultivars. The malondialdehyde content was found highest in GT60, followed by ROC22, and GT47. The exo-β-1,4-glucanase/ cellobiohydrolase activity was found highest in the margin of GT47 than lateral and medial axis of ROC22 and GT60. The axis activity increased exponentially, and ROC22 gradually decreased from the periphery of the mid-axis and lower than GT47 and GT60 in the lateral and mid-axis of leaf. In conclusion, the mature leaves are easy to defoliate mainly loose leaf sheaths, large leaf sheath inclination angles, more deformation during the growth period of the abscission zone, early with large cracks, and slow browning process. Leaf sheaths with high fibre and lignin content showed significant hardness and thickness. The sugarcane cultivars showed positive correlation between peroxidase and malondialdehyde content with the browning process at the base of mature leaf sheaths.

Inheritance pattern of Qualitative traits, Genetic analysis and association of yield attributes in F2 populations of Rice (Oryza sativa)

Understanding the extent of genetic variability within the segregating generations is crucial for identifying superior segregants with high yield and better market acceptability. Thus, the present study was carried out to quantify the extent of genetic variation available in the segregating population of rice. Three crosses, viz., CO 55 × IC 457996, CO 55 × IC 464685, and CO 55 × IC 115439 were evaluated using a non-randomized experimental design for six yield attributing and two physical grain quality traits in F2 generation. The inheritance pattern of basal leaf sheath colour and grain colour in CO 55 × IC 115439 indicate digenic complementary gene interaction (9:7), whereas grain colour in CO 55 × IC 464685 exhibits inhibitory gene action (13:3). The positively skewed nature of productive tillers per plant and single-plant yield in the F2 segregants emphasizes the need for intensive selection to facilitate rapid improvement due to the influence of complementary gene action. Moderate to high GCV with high heritability and GAM for traits such as plant height, productive tillers per plant, hundred seed weight, grain width, and single-plant yield in the F2 segregants underscore the prevalence of additive gene action and thus provide the most effective condition for simple phenotypic selection. Moreover, productive tillers per plant and single-plant yield showed a strong positive association in all the crosses. Therefore, productive tillers per plant can be considered an indicator trait when selecting high-yielding segregants for grain yield improvement.

Ant13 Encodes Regulatory Factor WD40 Controlling Anthocyanin and Proanthocyanidin Synthesis in Barley (Hordeum vulgare L.)

Flavonoid compounds like anthocyanins and proanthocyanidins are important plant secondary metabolites having wide biological activities for humans. In this study, the molecular function of the Ant13 locus, which is one of the key loci governing flavonoid synthesis in barley, was determined. It was found that Ant13 encodes a WD40-type regulatory protein, which is required for transcriptional activation of a set of structural genes encoding enzymes of flavonoid biosynthesis at the leaf sheath base (colored by anthocyanins) and in grains (which accumulate proanthocyanidins). Besides its role in flavonoid biosynthesis, pleiotropic effects of this gene in plant growth were revealed. The mutants deficient in the Ant13 locus showed similar germination rates but a decreased rate of root and shoot growth and yield-related parameters in comparison to the parental cultivars. This is the seventh Ant locus (among 30) for which molecular functions in flavonoid biosynthesis regulation have been determined.

Relationship between the anthocyanin content values in the leaf sheath base of barley cultivars and in the grain of the hybrids derived from them

Background. The development of barley cultivars accumulating anthocyanins in grain is an important task for breeding, which is based on the Ant1 and Ant2 genes that control synthesis of these compounds. To optimize the breeding strategy and selection of the initial material, quantitative assay of anthocyanin content in the leaf sheath base of barley cultivars was carried out and the relationship between this parameter for some of the barley cultivars and anthocyanin content in grain of the hybrids derived from them was evaluated.Materials and methods. The anthocyanin content in the leaf sheath base was studied in 32 barley cultivars in the tillering stage and in mature grains of 11 purple-grain hybrids selected from the hybrid populations using DNA-markers.Results and discussion. It was shown that there were quantitative differences in the anthocyanin content in the leaf sheath base among barley cultivars, which varied from 1 to 191 mg/kg. A cluster analysis helped to identify three groups of cultivars: with low, medium and high anthocyanin content. The hybrids from crossing cultivars differing in their anthocyanin content in the leaf sheath base with line P18, the donor of the dominant allele of the Ant2 gene, showed variation of the anthocyanin content in grain from 22 to 71 mg/kg. The observed differences among the hybrids were determined by the genotypes of individual plants and the allelic state of Ant2. A weak correlation (rs = 0.37, p = 0.0362) was shown between the anthocyanin contents in the leaf sheath base and in the grain of the obtained hybrids.Conclusion. The results of the study would help to optimize the breeding strategy for the development of new barley cultivars with high anthocyanin content in the grain and substantiate the need to test the anthocyanin content in the grain of individual lines.

Phenotypic characterization of aromatic rice (Oryza sativa L.) landraces of Odisha, India

A total of 127 accessions of aromatic short grain rice were collected with detailed passport informationfrom 30 districts of Odisha, India. The agro-morphological characters of all the landraces wererecordedaccording to Distinctiveness, Uniformity and Stability (DUS) guidelines with 21 qualitative and 16quantitative characters and statistically analysed. Out of the different qualitative traits studied, ligule colour,panicle type, secondary branching, panicle axis and awning were found to be dimorphic; blade colour,blade pubescence, basal leaf sheath colour, collar colour, auricle colour, internode colour, culm strength,panicle exsertion, sterile lemma colour and stigma colour were trimorphic; leaf angle, culm angle, flag leafangle, apiculus colour and lemma palea colour were tetramorphic. Variations were observed for all thequalitative traits except the presence of collar, auricles, and split shaped ligule among the accessions. Thehighest frequency was observed for panicle architecture; the presence of secondary branching (96%) anddrooping type of panicle axis (95.3%).The weight of 1000 grain wt. which is a key character for selectinghigh yield variety, varied from 11.86g (Ranimasuri) to 23.09g (Kalkati). Similarly, panicle weight variedfrom 1.42g (Siresa) to 3.7g (Tulasiphool). The days to 50% flowering varied from 85.5 (Basumati) to 131(Basauoga) with a mean of 111.17 days indicating that they are mostly medium to late flowering landraces.High grain yield landraces are Basapatri2, Basumati, Kalkatia, Tulasibas. These landraces may be popularizedamong the farmers and the same may be used in hybridization programmes for varietal development.

Cell-Type-Dependent but CME-Independent Polar Localization of Silicon Transporters in Rice.

Silicon (Si) is an important nutrient required for sustainable and high production of rice and its uptake is mediated by a pair of influx (OsLsi1)-efflux (OsLsi2) transporters showing polar localization. However, the mechanisms underlying their polarity are unknown. Here, we revealed that the polarity of the Si transporters depends on cell types. The polar localization of both OsLsi1 and OsLsi2 was not altered by Si supply, but their protein abundance was reduced. Double immunostaining showed that localization of OsLsi1 and OsLsi2 was separated at the edge of the lateral polar domain by Casparian strips in the endodermis, whereas they were slightly overlapped at the transversal side of the exodermis. When OsLsi1 was ectopically expressed in the shoots, it showed polar localization at the xylem parenchyma cells of the basal node and leaf sheath, but not at the phloem companion cells. Ectopic expression of non-polar Si transporters, barley HvLsi2 and maize ZmLsi2 in rice, resulted in their polar localization at the proximal side. The polar localization of OsLsi1 and OsLsi2 was not altered by inhibition of clathrin-mediated endocytosis (CME) by dominant-negative induction of dynamin-related protein1A and knockout of mu subunit of adaptor protein 2 complex, although the knockout mutants of OsAP2M gene showed dwarf phenotype. These results indicate that CME is not required for the polar localization of Si transporters. Taken together, our results indicate that CME-independent machinery controls the polar localization of Si transporters in exodermis, endodermis of root cells and xylem parenchyma cells.

LAZY2 controls rice tiller angle through regulating starch biosynthesis in gravity-sensing cells.

Rice (Oryza sativa) tiller angle is a key component for achieving ideal plant architecture and higher grain yield. However, the molecular mechanism underlying rice tiller angle remains elusive. We characterized a novel rice tiller angle mutant lazy2 (la2) and isolated the causative gene LA2 through map-based cloning. Biochemical, molecular and genetic studies were conducted to elucidate the LA2-involved tiller angle regulatory mechanism. The la2 mutant shows large tiller angle with impaired shoot gravitropism and defective asymmetric distribution of auxin. We found that starch granules in amyloplasts are completely lost in the gravity-sensing leaf sheath base cells of la2, whereas the seed development is not affected. LA2 encodes a novel chloroplastic protein that can interact with the starch biosynthetic enzyme Oryza sativa plastidic phosphoglucomutase (OspPGM) to regulate starch biosynthesis in rice shoot gravity-sensing cells. Genetic analysis showed that LA2 regulates shoot gravitropism and tiller angle by acting upstream of LA1 to mediate lateral auxin transport. Our studies revealed that LA2 acts as a novel regulator of rice tiller angle by specifically regulating starch biosynthesis in gravity-sensing cells, and established the framework of the starch-statolith-dependent rice tiller angle regulatory pathway, providing new insights into the rice tiller angle regulatory network.

Assessment of 60Co gamma radiation on early phenological stages of two generations of OFADA rice

Traditional Ofada rice varieties from South-West, Nigeria is preferred for its unique taste, aroma and massive potential for export but has low yield. Based on this background, two Ofada rice varieties, FUNAABOR 1 and FUNAABOR 2 were irradiated to create genetic variability as it affects vegetative traits. Seeds from the varieties were exposed to nine levels of 60Co gamma irradiation (0, 50, 100, 150, 200, 250, 300, 350 and 400 Gy). The seeds were nursed for 30 days before M1 seedlings were transplanted into a well tilled soil in a two factorial RCBD with three replicates. Selections from M1 plants were used to establish M2 plants generation. The results revealed diverse effects of 60Co gamma irradiation treatments on different plant vegetative traits. The establishment rates of M1 Ofada rice population were unaffected (p > 0.01) by increasing gamma irradiation from 0 to 300 Gy but decreased at 350 Gy. Above 300 Gy, tiller numbers, plant height, lodging incidence, leaf number, leaf length and leaf angle decreased significantly when compared with control (p < 0.01) in both generations (M1 and M2). Moderately tillered (10 tillers), tall plant (116.9 cm) obtained from 350 dosage rate recorded highest grain weight of 7.8 g per panicle. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) promoted by the irradiation dosages in M1 selection indicate the extent of environmental influence. High broad sense heritability observed from leaf number, leaf angle, leaf length, leaf blade colour, basal leaf sheath colour and grain weight per panicle shows possibility of rapid genetic improvement of these characters through selection.

Evidence on vegetative and inflorescence morphology of Chloranthaceae (Angiospermae) from the Early Cretaceous (middle–late Albian) of Spain

The near-basal angiosperm family Chloranthaceae (with four living genera) is prominently represented in the Early Cretaceous fossil record by pollen and flowers, but its leaves, other vegetative parts and inflorescences are less well known. Here, we report impressions of leaves, stems and inflorescences from the middle–late Albian Escucha Formation of Teruel Province (NE Spain) that help redress this imbalance and bring into clearer focus the morphological and systematic diversity of this key group in the early angiosperm radiation. We used parsimony analysis of a morphological dataset of living and fossil Chloranthaceae to evaluate the position of the fossils on a molecular-based tree of extant taxa. Todziaphyllum elongatum gen. et sp. nov., with festooned semicraspedodromous venation and asymmetrical chloranthoid teeth, is most parsimoniously placed on the stem lineage of the living genus Hedyosmum. Leaves of Alcainea eklundiae gen. et sp. nov., with festooned semicraspedodromous venation and symmetric teeth, occur attached to stems in opposite pairs at swollen nodes with sheathing leaf bases and interpetiolar stipules, along with compound spikes of flowers with a monosymmetric androecium of three stamens, each flower subtended by a bract. This represents the first time that fossil leaves, stems and inflorescences of Chloranthaceae have been found in organic connection. Alcainea may be sister to Sarcandra, Chloranthus or the clade consisting of both genera, like the mesofossil Canrightiopsis. Leaf Type A, with festooned craspedodromous venation and symmetrical teeth, may be related to Ascarina. These observations provide direct evidence for the distinctive vegetative and inflorescence morphology of Chloranthaceae in the Early Cretaceous. They are consistent with the level of diversification inferred from coeval chloranthaceous pollen and floral mesofossils, including lines nested in crown group Chloranthaceae but not in any of living genera, and exhibiting character combinations not retained in living Chloranthaceae. http://zoobank.org/urn:lsid:zoobank.org:pub:08B96BA0-3B27-48A1-9E8F-CB5811AE8C07

Mutations in a�Golden2-Like�Gene Cause Reduced Seed Weight in�Barley�albino lemma 1�Mutants.

The albino lemma 1 (alm1) mutants of barley (Hordeum vulgare L.) exhibit obvious chlorophyll-deficient hulls. Hulls are seed-enclosing tissues on the spike, consisting of the lemma and palea. The alm1 phenotype is also expressed in the pericarp, culm nodes and basal leaf sheaths, but leaf blades and awns are normal green. A single recessive nuclear gene controls tissue-specific alm1 phenotypic expression. Positional cloning revealed that the ALM1 gene encodes a Golden 2-like (GLK) transcription factor, HvGLK2, belonging to the GARP subfamily of Myb transcription factors. This finding was validated by genetic evidence indicating that all 10 alm1 mutants studied had a lesion in functionally important regions of HvGLK2, including the three alpha-helix domains, an AREAEAA motif and the GCT box. Transmission electron microscopy revealed that, in lemmas of the alm1.g mutant, the chloroplasts lacked thylakoid membranes, instead of stacked thylakoid grana in wild-type chloroplasts. Compared with wild type, alm1.g plants showed similar levels of leaf photosynthesis but reduced spike photosynthesis by 34%. The alm1.g mutant and the alm1.a mutant showed a reduction in 100-grain weight by 15.8% and 23.1%, respectively. As in other plants, barley has HvGLK2 and a paralog, HvGLK1. In flag leaves and awns, HvGLK2 and HvGLK1 are expressed at moderate levels, but in hulls, HvGLK1 expression was barely detectable compared with HvGLK2. Barley alm1/Hvglk2 mutants exhibit more severe phenotypes than glk2 mutants of other plant species reported to date. The severe alm1 phenotypic expression in multiple tissues indicates that HvGLK2 plays some roles that are nonredundant with HvGLK1.

Dactylorhiza hatagirea (D. Don) Soo: A Critically Endangered Perennial Orchid from the North-West Himalayas.

Dactylorhiza hatagirea (Orchidaceae) is a perennial herb inhabiting sub-alpine to alpine regions, ranging at elevations between 2500 and 5000 m.a.s.l. With palmately lobed rhizome and lanceolate leaves having a sheathing leaf base, it bears pink flowers with purple-colored notches and a curved spur. It finds wide use in ayurveda, siddha, unani, and folk medicine in curing disorders of the circulatory, respiratory, nervous, digestive, skeletal, and reproductive systems, besides boosting the immune system to fight infectious diseases. Secondary metabolites such as dactylorhins A–E, dactyloses A–B, and others exhibit a wide spectrum of pharmacological activities (antioxidant, antimicrobial, antiseptic, anticancer, and immune enhancing activities). Its use as a dietary supplement was found to be beneficial in increasing testosterone levels, resulting in improved sexual desire and arousal. Incessant overexploitation of this medicinally important herb has resulted in the dwindling of its populations in the wild, which has resulted in its classification as a critically endangered plant species. Efforts involving mass reproduction through in vitro (through tissue culture) and in vivo (by vegetative propagation) means are currently being made to maintain the germplasm of this critically endangered orchid. Holding immense significance in clinical research and drug discovery, work on the genomic front (transcriptomics) has recently been carried out to discover the wealth of unexplored genetic information for this perennial herb. The present study is aimed at reviewing different aspects of the orchid to present collective (summarized) information on this medicinally important herb in the present, particularly its botany, ethnobotanical uses, phytochemistry, and pharmacognosy, along with the strategies that need to be adopted to prevent its overexploitation in natural habitats.

Study of morphological diversity of rice landraces (Oryza sativa.L)

An investigation was carried out to characterize 97 rice (Oryza sativa L.) land races for 24 different morphological traits using DUS (Distinctiveness, Uniformity, Stability) characters. A total of three characters viz., leaf auricles, leaf ligules and leaf shape of ligule were found to be monomorphic. The characters namely leaf anthocyanin colouration, leaf sheath anthocyanin colouration, panicle awns, panicle distribution of awns and leaf pubescence of blade surface were recorded as dimorphic. Seven traits viz., coleoptile colour, leaf intensity of green colour, ligule colour, leaf anthocyanin colouration of auricles, panicle exertion, leaf length of blade and leaf width of blade were of trimorphic. Five traits namely basal leaf sheath colour, culm attitude, flag leaf attitude of blade (early and late observation), panicle curvature of main axis were recorded four states of expression. The traits viz., spikelet colour of stigma, stem length, days to 50% flowering and time to maturity were showed five states of expression. The DUS characterization for these characters will be useful for rice breeders to restore the superior genes and use it in crop improvement programmes. Presence of uniform purple colour in whole plant incluing ligule and auricles was observed in purple puttu and chitansamba and can be used as morphological markers. The land races namely Ayyan samba and red sirumani were found to be the early maturity types. The short stem length and erect culms were observed in senthooram and seevansamba and these genotypes withstand lodging. Hence, these land races would be used as donors for the development of short duration and lodging resistance respectively in rice improvement programme.

Pepelnica pšenice (Blumeria graminis (DC.) Speer f. sp. tritici (Em. Marchal)) sve češći problem u usjevima pšenice na Unsko-sanskom kantonu u BiH

In 2018. wheat fields on the territory North-western part of Bosnia and Herzegovina were regularly inspected. Occurrence of the causal agent of wheat powdery mildew, Blumeria graminis (DC) f. sp. tritici Speer (syn. Erysiphe graminis DC f. sp. tritici Marchal)) was registered in a large number of localities. In vegetation period, symptoms characteristic for this fungus were observed on all green plant organs, but it was most commonly present on leaves and basal leaf sheaths of wheat plants. Microscopic preparations were made from samples of diseased parts of wheat in the laboratory of the Biotechnical Faculty. Chasmothecia and conidia were observed under the microscope. Chasmothecia and conidia were registered under the microscope. In 2018, presence of the pathogen was registered on about 60% of the total wheat sowed. Disease Index (DI) was calculated using the McKinney formula. The disease index represents the percentage of the disease.The intensity of plant infection was ranged on a scale 0-9. The disease index above 35% was registered on about 56.6% of the infected plants and 40% total wheat plants. After harvest, grains from infected wheat plants were measured for absolute and hectoliter weigts, which were found to range from 25 to 42 g and from 60 to 67 kg, respectively. To improve the effectiveness of crop protection, it is necessary to apply the required agricultural practices: long-term crop rotation, control of volunteer wheat and grassy weeds of the family Poaceae, deep plowing, balanced fertilization, optimum sowing time and others. The main strategy to control powdery mildew is by using resistant cultivars the disease can also be controlled by fungicide treatments.

Phenotypic diversity of the tidal swamp rice (Oryza sativa L.) germplasm from South Kalimantan, Indonesia

Tidal swamp rice is a valuable source for developing new rice cultivars in the future because they possess some important traits for, adapted to a wide range of abiotic and biotic stresses. In this study, twenty-seven cultivars of the tidal swamp rice, comprising 26 from the South Kalimantan and one of Sumatera Island, Indonesia (an outgroup), were characterized phenotypically. Following Biodiversity International procedure, 14 qualitative and 15 quantitative traits were observed. The results show that this germplasm has a unique diversity in phenotypic traits. The secondary branch of panicle was the highest diversity of qualitative traits with an index of 0.93. Similarly, the plant height was the highest for quantitative traits (0.70). The correlation analysis confirmed that plant height, strongly correlated to culm diameter, the number of tillers and grain ratio. The PCA indicated that several independent traits, such as coleoptile anthocyanin coloration, basal leaf sheath color, and grain length, have positively contributed to the diversity, accounting 62.99%. Based on PCA analysis, the tidal swamp rice were clustered into four groups. According to UPGMA, this germplasm separated into six main groups, where Sardani (an outgroup) was very closely related to Lakatan Pacar and most distantly to Siam Perak. This information would be useful for the future rice breeding program, particularly in developing new rice cultivars in the tidal swamp areas.

Fundamental parenchyma cells are involved in Na+ and Cl- removal ability in rice leaf sheath.

Salt sensitivity in rice plants is associated with the accumulated amount of Na+ and Cl- in shoots and, more significantly, in photosynthetic tissues. Therefore, salt removal ability at the leaf sheath level is an important mechanism of salt tolerance. In the present study we attempted to determine whether rice leaf sheaths excluded Cl- as well as Na+, and to identify the tissues that were involved in the removal ability of both ions. In two rice genotypes, salt-tolerant FL478 and -sensitive IR29, leaf sheaths excluded Na+ and Cl- under NaCl treatment as estimated using their sheath:blade ratios. The sheath:blade ratio of Na+ but not of Cl-, was increased by NaCl treatment. Under NaCl treatment, Na+ concentration was higher in the basal leaf sheath, whereas Cl- concentration was higher in the middle and tip parts. At the tissue level, fundamental parenchyma cells of leaf sheaths retained the highest amounts of Na and Cl when treated with high amount of NaCl. These results imply that the leaf sheath potentially functions to remove excess Na+ and Cl- from xylem vessels in different locations along the axis, with the fundamental parenchyma cells of leaf sheaths being involved in over-accumulation of both Na+ and Cl-.

Morphological Character of Local Irrigated Rice on Farmer Field in North Sulawesi

<p>Local rice is a potential germplasm as a source of genes that control important properties in rice plants. The research aimed to characterize the morphological character of local rice cultivars of North Sulawesi. The research was conducted from January to June 2015 in North Sulawesi. The method used was the descriptive qualitative method. Exploration was done by collecting samples of local rice cultivars in North Sulawesi. Each cultivar was characterized its morphological characters according to the Characterization and Evaluation Guidelines of Rice Germplasm. The local rice found in North Sulawesi were 10 varieties, namely Pulo Sawah, Superwin, CK, Serwo, Pilihan, Sako, Sito Merah, Sito Putih, TB, and Serayu. There were similarities of the characters from all local rice varieties of North Sulawesi, such as culm (culm strength and culm habit), leaf character (basal leaf sheath color, leaf blade color, collar color, and auricle color), and flower character (panicle exsertion and panicle attitude of branches). The character of grain morphology was very diverse for all local rice varieties of North Sulawesi.</p>

Effects of plant growth regulators in heliconia ‘Red Opal’

The objective of this study was to evaluate growth regulators with purpose of reducing the size of heliconia ‘Red Opal’ potted plants. The experiment was carried out in randomized block design with five treatments (trinexapac-ethyl and paclobutrazol at rates of 37.5 and 75.0 mg of active ingredient per pot and control without growth regulator) and five replicates. The treatments were applied 40 days after planting the rhizomes in pots filled with soil. Thirty and 150 days after the growth regulator application, plant height, number of leaves and shoots, petioles length and leaf area were evaluated. One year after planting the rhizomes in pots the number of inflorescence and leaves (leaves, sheathing leaf bases and inflorescences) and rhizomes (rhizomes and roots) dry mass were determined. Trinexapac-ethyl had no differences compared to the control in any of the variables evaluated. Paclobutrazol proved effective in reducing plant height, leaf area and petiole length and increase in number of leaves and shoots but the effect was temporary. Also, it did not affect the inflorescences production and leaves and rhizomes dry mass. Paclobutrazol is efficient to promote height reduction and to increase the number of shoots in heliconia ‘Red Opal’ potted plants without affect the inflorescence formation but its effects is temporary.

Growth, nutrient accumulation and export by heliconia ‘Red Opal’

Synchronizing the timing of fertilizer applications with plant nutrient demand increases the nutritional efficiency and decrease the cost of production. The objective of this study was to determine the growth and the nutrient uptake and export by heliconia ‘Red Opal’. The experiment was carried out in a shade house and Heliconia psittacorum ‘Red Opal’ rhizomes were planted in soil classified as Arenic Kandinstults. The experimental design was completely randomized with nine plant sampling (zero; 30; 90; 150; 210; 270; 330; 390 and 450 days after planting) and five replicates. Leaves, sheathing leaf bases, flower stem, rhizomes and roots were collected every sampling and dry mass and nutrients accumulation were determined. Heliconia plants showed slow initial development but from the 210 days of planting, which corresponds with the beginning of the flower stem harvest there is a marked increase in dry mass accumulation. Nutrient accumulation followed the decreasing order: K > N = Ca > P = Mg > S > Fe = Mn > Zn > Cu = B. Potassium and calcium were the most exported macronutrients by heliconia flower stem and among the micronutrients, manganese was the most exported.

English

This experiment was carried out to determine the genotypic variation among rice (Oryza sativa) accessions using simple sequence repeats (SSR) markers. In the present study, a total of 12 SSR markers were used across 87 rice accessions from six countries. NTSYS-pc and PowerMarker software were used for data analysis. Six primers out of these 12 primers showed DNA amplification and polymorphism among the 87 rice accessions. The number of alleles detected by these six primers ranged from 2 to 9 with an average of 6.83 while polymorphism information content (PIC) ranged from 0.34 to 0.79 with an average of 0.55. The unweighted pair group method with arithmetic averages (UPGMA) cluster dendrogram generated based on the six SSR markers grouped the accessions into 4 clusters with 41% similarity coefficient. Accessions from these four clusters have late maturity, green basal leaf sheath colour, no awn and fewer tillers, respectively. This experiment has proven that even a small number of SSR markers are effective in assessing genetic diversity in rice. The genetic diversity revealed by the SSR markers in this study would be very important to select potentially good genotypes for future rice improvement programmes. Key words: Dendrogram, genetic diversity, molecular markers, rice.

Report of banana pseudostem weevil (Odoiporus longicollis Olivier) infestation on leaf petiole

During our survey a different site of infestation by Odoiporus longicollis was observed in ˜Nendran cultivar plots at Konny, Pathanamthitta District, Kerala. Feeding and exit holes of the grubs were observed on leaf petioles. Absence of continuous grub feeding channels from leaf sheath base to petiole suggests direct oviposition on the petiole.